NISTIR 7423
Building for Environmental and Economic Sustainability
Technical Manual and User Guide
Barbara C. Lippiatt
MIST
National Institute of Standards and Technology
Technology Administration, U.S. Department of Commerce
-------
-------
NISTIR 7423
Building for Environmental and Economic Sustainability
Technical Manual and User Guide
Barbara C. Lippiatt
Office of Applied Economics
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899-8603
Sponsored by:
National Institute of Standards and Technology
Building and Fire Research Laboratory
August 2007
U.S. Department Of Commerce
Carlos M. Gutierrez, Secretary
Technology Administration
Robert C. Cresanti, Under Secretary for Technology
National Institute of Standards and Technology
William A. Jeffrey, Director
-------
IV
-------
Abstract
The BEES (Building for Environmental and Economic Sustainability) version 4.0 software
implements a rational, systematic technique for selecting environmentally-preferred, cost-
effective building products. The technique is based on consensus standards and designed to be
practical, flexible, and transparent. The Windows-based decision support software, aimed at
designers, builders, and product manufacturers, includes actual environmental and economic
performance data for over 230 building products across a range of functional applications. BEES
measures the environmental performance of building products using the environmental life-cycle
assessment approach specified in International Organization for Standardization (ISO) 14040
standards. All stages in the life of a product are analyzed: raw material acquisition, manufacture,
transportation, installation, use, and waste management. Economic performance is measured
using the ASTM International standard life-cycle cost method (E917), which covers the costs of
initial investment, replacement, operation, maintenance and repair, and disposal. Environmental
and economic performance are combined into an overall performance measure using the ASTM
standard for Multiattribute Decision Analysis (E1765). For the entire BEES analysis, building
products are defined and classified based on the ASTM standard classification for building
elements known as UNIFORMAT II (El557).
Key words: Building products, economic performance, environmental performance, green
buildings, life cycle assessment, life-cycle costing, multiattribute decision analysis, sustainable
development
Disclaimer
Certain trade names and company products are mentioned throughout the text. In no case does
such identification imply recommendation or endorsement by the National Institute of
Standards and Technology, nor does it imply that the product is the best available for the
purpose.
The policy of the National Institute of Standards and Technology is to use metric units in all
its published materials. Since this software product is intended for U.S. manufacturers and
users of building products who evaluate performance using customary units, it is more
practical and less confusing in some cases to use the customary rather than metric units.
Where possible, however, both metric units and their customary equivalents are reported.
-------
Acknowledgments
The BEES tool could not have been completed without the help of others. Thanks are due the
NIST Building and Fire Research Laboratory (BFRL) for its support of this work from its
inception in 1994. Thanks are due the U.S. Department of Agriculture Office of the Chief
Economist for supporting development of BEES results for biobased products, and the U.S.
Environmental Protection Agency (EPA) Pollution Prevention Division for its support over the
years. Deserving special thanks is the BEES environmental data development team from Four
Elements, LLC and First Environment, Inc. for its superb data development, documentation, and
technical support. Special recognition is due Four Elements' Anne Landfield Greig, whose
technical expertise, diligence, patience, and unwavering support have contributed in no small
measure to the success of BEES. Jane Bare, of the EPA Office of Research and Development,
Sustainable Technology Division, and her TRACT team (particularly Greg Norris of Sylvatica,
Inc. and Tom Gloria, formerly of Five Winds International) were instrumental in developing the
life cycle impact assessment methods incorporated into BEES, and continue to go out of their
way to help the author adapt these methods to the practicalities of BEES. Thanks are also due
Tom Gloria and Jennifer Cooper of Five Winds International for their technical support for the
BEES Stakeholder Panel convened at NIST in May 2006, as well as Lawrence Berkeley National
Laboratory for providing the Energy Star "Cool Roof data used to analyze BEES roof covering
alternatives. The author is particularly grateful for the key cooperation and support offered by a
wide variety of industry associations and manufacturers with products represented in BEES.
Their cooperation exceeded all expectations, and led to a significant expansion and refinement of
the underlying BEES performance data. The comments of NIST BFRL colleagues Doug Thomas
and Cindy Reed inspired many improvements. Special thanks are due Julie Wean for heroically
incorporating more than 230 products, including their online documentation, into BEES 4.0, and for
carefully helping test and review the tool. Thanks are also due Tessa Beavers for her outstanding
administrative support.
Copyright Information
This software was developed at the National Institute of Standards and Technology by
employees of the Federal Government in the course of their official duties. Pursuant to title 17
Section 105 of the United States Code this software is not subject to copyright protection and
is in the public domain.
We would appreciate acknowledgement if the software is used.
VI
-------
Getting Started
System Requirements
BEES 4.0 runs on Windows 95 and beyond personal computers with at least 60 MB of available
disk space. At least one printer must be installed.
Uninstalling BEES 3.0
While uninstalling BEES 3.0 is not necessary to run BEES 4.0, you may choose to do so. All
BEES 3.0 files are contained in the folder in which you installed BEES 3.0 (usually
C:\BEES30d). Thus, the entire BEES 3.0 program may be uninstalled by simply deleting that
folder. If you choose to leave BEES 3.0 on your system, do not install BEES 4.0 to its folder.
Installing BEES 4.0
From Download Site. Once you've completed the BEES registration form, click Submit, and
then click BEES40zip.exe to download the self-extracting file. If prompted during the
download, choose to save the file, taking note of the folder to which it is saved. Once
downloaded, from Windows Explorer, go to the folder containing BEES40zip.exe and double
click on the file to begin the self-extraction process. Choose to unzip the file to a new folder by
entering a new folder name when prompted. Click Unzip. Once unzipped, from Windows
Explorer double click on the file SETUP.EXE in your new folder to begin the self-explanatory
BEES 4.0 installation process. During installation, you will need to choose a folder in which to
install BEES 4.0; you must choose a folder different from the one containing the setup file
(SETUP.EXE). Once installation is complete, you are ready to run BEES 4.0 by selecting
Start-»Programs->-BEES->-BEES 4.0.
From CD-ROM. Install BEES by inserting the compact disc into your CD-ROM drive and
running the BEES setup program, SETUP.EXE. Follow on-screen installation instructions. Once
installation is complete, you are ready to run BEES 4.0 by selecting
Start-»Programs->-BEES->-BEES 4.0.
Running BEES
First time BEES users may find it helpful to read the BEES Tutorial, found in section 4 of this
report. Section 4 is a document-based version of the BEES 4.0 Tutorial topic of the software's
on-line help system, with step-by-step instructions for running the software. The section also
includes illustrations of the screen displays. Alternatively, first-time users may choose to double-
click on the BEES 4.0 Help icon included in the BEES program group at installation for a self-
contained electronic version of the entire online help system.
While running the BEES software, context-sensitive help is often available from the BEES Main
Menu. Context-sensitive help is also available through Help buttons on many of the BEES
windows.
Technical Support
For questions regarding the BEES model or software, contact blippiatt@nist.gov.
Vll
-------
Vlll
-------
Contents
Abstract v
Acknowledgements vi
Getting Started vii
Contents ix
List of Tables xiii
List of Figures xvii
1. Background and Introduction 1
2. The BEES Model 3
2.1 Environmental Performance 3
2.1.1 Goal and Scope Definition 4
2.1.2 Inventory Analysis 7
2.1.3 Impact Assessment 8
2.1.3.1 Impact Assessment Methods 8
2.1.3.2 Characterizing Impacts in BEES 11
2.1.3.3 Normalizing Impacts in BEES 24
2.1.4 Interpretation 26
2.1.4.1 EPA Science Advisory Board Study 26
2.1.4.2 BEES Stakeholder Panel Judgment 28
2.2 Economic Performance 33
2.3 Overall Performance 35
2.4 Limitations 35
3. BEES Product Data 39
3.1 Concrete Slabs, Walls, Beams, and Columns 39
3.1.1 Generic Portland Cement Products 39
3.1.2 Lafarge North America Products 52
3.2 Roof and Wall Sheathing 58
3.2.1 Generic Oriented Strand Board Sheathing 58
3.2.2 Generic Plywood Sheathing 63
3.3 Exterior Wall Systems 68
3.3.1 CENTRIA Formawall Insulated Composite Panel 68
3.4 Exterior Wall Finishes 72
3.4.1 Generic Brick & Mortar 72
3.4.2 Generic Stucco 77
3.4.3 Generic Aluminum Siding 82
3.4.4 Generic Cedar Siding 87
3.4.5 Generic Vinyl Siding 91
3.4.6 Trespa Meteon Panel 95
3.4.7 Headwaters Stucco Finish Application 95
3.4.8 DryvitEIFS Cladding Outsulation 99
3.5 Insulation 105
3.5.1 Generic Cellulose 105
3.5.2 Generic Fiberglass 109
3.5.3 Generic Mineral Wool 113
IX
-------
3.6 Framing 117
3.6.1 Generic Steel Framing 117
3.6.2 Generic Wool Framing 119
3.7 Exterior Sealers and Coatings 124
3.7.1 BioPreserve SoyGuard Wood Sealer 124
3.8 Roof Coverings 126
3.8.1 Generic Asphalt Shingles 126
3.8.2 Generic Clay Tile 131
3.8.3 Generic Fiber Cement Shingles 135
3.9 Roof Coatings 139
3.9.1 Prime Coatings Utilithane 139
3.10 Partitions 141
3.10.1 Generic Gypsum 141
3.10.2 Trespa Virtuon and Athlon Panels 145
3.10.3 P&M Plastics Altree Panels 145
3.11 Fabricated Toilets Partitions, Lockers, Ceiling Finishes, Fixed Casework, Table
Tops/Counter Tops/Shelving 148
3.11.1 Trespa Composite Panels 148
3.12 Wall Finishes to Interior Walls 151
3.12.1 Generic Latex Paint Products 151
3.13 Floor Coverings 158
3.13.1 Generic Ceramic Tile with Recycled Glass 158
3.13.2 Generic Linoleum Flooring 160
3.13.3 Generic Vinyl Composition Tile 165
3.13.4 Generic Composite Marble Tile 169
3.13.5 Generic Terrazzo 172
3.13.6 Generic Nylon Carpet 175
3.13.7 Generic Wool Carpet 179
3.13.8ForboLinoleum 183
3.13.9 UTT Soy Backed Nylon Carpet 186
3.13.10 C&A Carpet 189
3.13.11 Interface Carpet 193
3.13.12 J&J Industries Carpet 198
3.13.13 Mohawk Carpet 201
3.13.14 Natural Cork Flooring 205
3.14 Chairs 209
3.14.1 Herman Miller Aeron Office Chair 209
3.14.2 Herman Miller Ambi and Generic Office Chair 212
3.15 Roadway Dust Control 215
3.15.1 Environmental Dust Control Dustlock 215
3.16 Parking Lot Paving 218
3.16.1 Generic Concrete Paving 218
3.16.2 Asphalt with GSB88 Seal-Bind Maintenance 222
3.16.3 Generic Asphalt with Traditional Maintenance 226
3.16.4 Lafarge Cement Concrete Paving 230
3.17 Fertilizers 229
-------
3.17.1 Perdue MicroStart 60 Fertilizer 229
3.17.2 Four All Seasons Fertilizer 232
3.18 Transformer Oil 235
3.18.1 Generic Mineral Transformer Oil 235
3.18.2 Generic Silicon Transformer Oil 238
3.18.3 Cooper Envirotemp FR3 241
3.18.4ABBBIOTEMP 243
3.18.5 Generic Biobased Transformer Oil 246
3.19 Carpet Cleaner 249
3.19.1 Racine Industries HOST Dry Carpet Cleaning System 249
3.20 Floor Stripper 253
3.20.1 Nano Green Floor Stripper 253
3.21 Glass Cleaner 257
3.21.1 Spartan Green Solutions Class Cleaner 257
3.22 Bath and Tile Cleaner 261
3.22.1 Spartan Green Solutions Restroom Cleaner 261
3.23 Grease & Graffiti Remover 264
3.23.1 VertecBio Gold Graffiti Remover 264
3.24 Adhesive and Mastic Remover 266
3.24.1 Franmar BEAN-e-doo Mastic Remover 266
3.24.2 Nano Green Mastic Remover 269
4. BEES Tutorial 271
4.1 Setting Parameters 271
4.2 Defining Alternatives 274
4.3 Viewing Results 276
4.4 Browsing Environmental and Economic Performance Data 281
5. Future Directions 293
Appendix A. BEES Computational Algorithms 295
A.I Environmental Performance 295
A.2 Economic Performance 296
A.3 Overall Performance 296
Appendix B. Interpreting BEES Environmental Performance Scores: A Primer 297
References 303
XI
-------
Xll
-------
List of Tables
Table 2.1 BEES Global Warming Potential Characterization Factors 12
Table 2.2 BEES Acidification Potential Characterization Factors 13
Table 2.3 BEES Eutrophication Potential Characterization Factors 14
Table 2.4 BEES Fossil Fuel Depletion Potential Characterization Factors 15
Table 2.5 BEES Habitat Alteration Potential Characterization Factors 18
Table 2.6 BEES Criteria Air Pollutant Characterization Factors 19
Table 2.7 Sampling of BEES Human Health Characterization Factors 21
Table 2.8 Sampling of BEES Smog Characterization Factors 22
Table 2.9 BEES Ozone Depletion Potential Characterization Factors 23
Table 2.10 Sampling of BEES Ecological Toxicity Potential Characterization Factors 24
Table 2.11 BEES Normalization Values 25
Table 2.12 Pairwise Comparison Values for Deriving Impact Category Importance Weights..27
Table 2.13 Relative Importance Weights based on Science Advisory Board Study 28
Table 2.14 Relative Importance Weights based on BEES Stakeholder Panel Judgments 30
Table 3.1 Concrete Constituent Quantities by Cement Blend and Compressive Strength
Of Concrete 45
Table 3.2 Portland Cement Constituents 46
Table 3.3 Energy Requirements for Portland Cement Manufacturing 47
Table 3.4 Energy Requirements for Ready Mix Concrete Production 48
Table 3.5 Concrete Form and Reinforcing Requirements 50
Table 3.6 Lafarge North America Concrete Products 53
Table 3.7 Lafarge North America Cement Constituents 56
Table 3.8 OSB Constituents 59
Table 3.9 OSB Production Energy 61
Table 3.10 OSB Manufacturing Site Emissions 61
Table 3.11 Plywood Sheathing Constituents 65
Table 3.12 Plywood Production Energy 66
Table 3.13 Plywood Production Emissions 66
Table 3.14 CENTRIA Formawall Insulated Composite Panel Constituents 69
Table 3.15 Energy Requirements for CENTRIA Formawall Insulated Panel Production 69
Table 3.16 Air Emissions from CENTRIA Formawall Insulated Panel Production 70
Table 3.17 Fired Brick Constituents 73
Table 3.18 Masonry Cement Constituents 74
Table 3.19EnergyRequirements forBrickManufacturing 74
Table 3.19a U.S. Brick Production by Census Region 75
Table 3.20 Density of Stucco by Type 77
Table 3.21 Stucco Constituents 79
Table 3.22 Masonry Cement Constituents 79
Table 3.23 Energy Requirements for Masonry Cement Manufacturing 79
Table 3.2'4Emissions from Masonry Cement Manufacturing 80
Table 3.25 Aluminum Siding Constituents 83
Table 3.26 Alloy Composition 84
Xlll
-------
Table 3.27 Energy Requirements for Aluminum Rolling 55
Table 3.28 Cedar Siding Production Energy 89
Table 3.29 Cedar Siding Production Process-Related Emissions 89
Table 3.30 Vinyl Siding Constituents 93
Table 3.31 Headwaters Cement Products 96
Table 3.32 Headwaters Cement Constituents 97
Table 3.33 Dryvit Product Constituents 702
Table 3.34 Energy Requirements for Mixing Dryvit Outsulation and Outsulation Plus 102
Table 3.35 Dryvit E1FS Constituents for Outsulation 103
Table 3.36 Dryvit EIFS Constituents for Outsulation Plus 104
Table 3.37 Blown Cellulose Insulation by Application 106
Table 3.38 Cellulose Insulation Constituents 707
Table 3.39 Energy Requirements for Cellulose Insulation Manufacturing 707
Table 3.40 Fiberglass Batt Mass by Application 709
Table 3.41 Blown Fiber glass Mass by Application 709
Table 3.42 Fiberglass Insulation Constituents 777
Table 3.43 Energy Requirements for Fiberglass Insulation Manufacturing 777
Table 3.44 Emissions for Fiberglass Insulation Manufacturing 777
Table 3.45 Raw Material Transportation Distances 772
Table 3.46 Blown Mineral Wool Mass by Application 114
Table 3.47 Mineral Wool Insulation Constituents 775
Table 3.48 Energy Requirements for Mineral Wool Insulation Manufacturing 775
Table 3.49 Emissions for Mineral Wool Insulation Manufacturing 775
Table 3.50 Lumber Production Energy 722
Table 3.51 Lumber Production Emissions 722
Table 3.52 SoyGuard Constituents 725
Table 3.53 Asphalt Shingles Constituents 725
Table 3.54 Type 15 Felt Underlayment Constituents 725
Table 3.55 Energy Requirements for Asphalt Shingle Manufacturing 725
Table 3.56 Asphalt Shingle Production Emissions 729
Table 3.57 Type-30 Roofing Felt Constituents 732
Table 3.58 Energy Requirements for Clay Tile Manufacturing 733
Table 3.59 Fiber Cement Shingle Constituents 136
Table 3.60 Type-30 Roofing Felt Constituents 737
Table 3.61 Energy Requirements for Fiber Shingle Manufacturing 737
Table 3.62 Prime Coatings Utilithane Manufacturing Energy 140
Table 3.63 Prime Coatings Utilithane Installation Energy 141
Table 3.64 Gypsum Board Constituents 142
Table 3.65 Energy Requirements for Gypsum Board 143
Table 3.66 Emissions from Gypsum Board Manufacturing 143
Table 3.66aP&MPlastics Altree Panel Constituents 146
Table 3.66b P&M Plastics Altree Panel Energy Requirements 146
Table 3.67 Trespa Composite Panel Constituents by Mass Fraction 750
Table 3.68 Trespa Composite Panel Density 757
Table 3.69 Virgin Latex Paint Constituents 154
Table 3.70 Latex Paint Resin Constituents 154
XIV
-------
Table 3.71 Consolidated Paint Sorting Data 156
Table 3.72 Consolidated Paint Processing Data 156
Table 3.73 Reprocessed Paint Sorting and Processing Data 757
Table 3.74 Ceramic Tile Constituents 759
Table 3.75 Latex/Mortar Blend Constituents 759
Table 3.76 Energy Requirements for Ceramic Tile Manufacturing 759
Table 3.77 Linoleum Constituents 162
Table 3.78 Inputs to Linseed Agriculture 162
Table 3.79 Electricity Inputs for Cork Flour Production 163
Table 3.80 Energy Requirements for Linoleum Manufacturing 163
Table 3.81 Emissions from Linoleum Manufacturing 163
Table 3.82 Linoleum Raw Materials Transportation 164
Table 3.83 Vinyl Composition Tile Constituents 167
Table 3.84 Energy Requirements for Vinyl Composition Tile Manufacturing 167
Table 3.85 Composite Marble Tile Constituents 770
Table 3.86 Latex/Mortar Blend Constituents 770
Table 3.87 Energy Requirements for Composite Marble Tile Manufacturing 7 77
Table 3.88 Terrazzo Flooring Constituents 773
Table 3.89 Energy Requirements for Terrazzo Manufacturing 174
Table 3.90 Terrazzo Flooring Installation Materials 174
Table 3.91 Nylon Carpet Constituents 777
Table 3.92 Energy Requirements for Nylon Carpet Manufacturing 775
Table 3.93 Wool Carpet Constituents 750
Table 3.94 Raw Wool Constituents 757
Table 3.95 Wool Yarn Production Requirements 757
Table 3.96 Wool Yarn Bleaching Inputs 752
Table 3.97 Energy Requirements for Wool Carpet Tufting 752
Table 3.98 Forbo Marmoleum Constituents 184
Table 3.99 UTTBroadloom Carpet Constituents 757
Table 3.100 C&A Products Included in BEES 759
Table 3.101C&AER3 Flooring Constituents 797
Table 3.102 C&A Ethos Flooring Constituents 797
Table 3.103C&A Products'Mass and Density 792
Table 3.104 Bentley Prince Street Commercial Carpet Constituents 795
Table 3.105 InterfaceFLOR Commercial Carpet Constituents 196
Table 3.106 Interface Carpet Density 797
Table 3.107 J&JCertificate Broadloom Carpet Constituents 799
Table 3.108 Mohawk Broadloom Carpet Constituents 203
Table 3.109 Mohawk Carpet Density 204
Table 3.110 Natural Cork Flooring Constituents 207
Table 3.111 Natural Cork Flooring Density 205
Table 3.112 Herman Miller Aeron Chair Major Constituents 270
Table 3.113 Herman Miller Ambi Chair Major Constituents 273
Table 3.114 Dustlock Installation Energy Requirements 277
Table 3.115 Concrete Constituents 279
Table 3.116 Energy Requirements for Ready Mix Concrete Production 220
XV
-------
Table 3.117 Energy Requirements for Dry Batch Concrete Production 220
Table 3.118 Hot Mix Asphalt Constituents 223
Table 3.119 Energy Requirements for Hot Mix Asphalt Production 224
Table 3.120 Emissions from Hot Mix Asphalt Production 224
Table 3.121 Energy Requirements for Asphalt Pavement Installation 225
Table 3.122 Energy Requirements for GSB88 Sealer-Binder Maintenance 225
Table 3.123 Hot Mix Asphalt Constituents 227
Table 3.124 Energy Requirements for Hot Mix Asphalt Production 227
Table 3.125 Emissions from Hot Mix Asphalt Production 227
Table 3.126 Energy Requirements for Asphalt Paving Installation 225
Table 3.127 Energy Requirements for Asphalt Resurfacing. 225
Table 3.128 Microstart 60 Constituents 230
Table 3.129 Microstart 60 Manufacturing Emissions 237
Table 3.130 Four All Seasons Energy Requirements 234
Table 3.131 Mineral-Oil Based Transformer Oil Constituents 236
Table 3.132 U.S. Average Refinery Energy Use 237
Table 3.133 Energy Requirements for Mineral-Oil Based Transformer Oil Production 235
Table 3.134 Envirotemp FR3 Constituents 241
Table 3.135 Envirotemp FR3 Manufacturing Energy 241
Table 3.136 BIOTEMP Transformer Oil Constituents 243
Table 3.137 Generic Biobased Transformer Oil Constituents 246
Table 3.138 Biobased Transformer Oil Manufacturing Energy 247
Table 3.139 HOST Dry Carpet Cleaning System Constituents 249
Table 3.140 HOST Processing Materials 257
Table 3.141 Nano Green Product Constituents 254
Table 3.142 Green Solution Glass Cleaner Constituents 255
Table 3.143 Green Solution Restroom Cleaner Constituents 262
Table 3.144 VertecBio Gold Graffiti Remover Constituents 265
Table 3.145 BEAN-e-doo Mastic Remover Constituents 267
Table 4.1 BEES Products Keyed to Environmental and Economic Performance Data Codes... 25 7
XVI
-------
List of Figures
Figure 2.1 Decision Criteria for Setting Product System Boundaries 5
Figure 2.2 BEES Inventory Data Categories 7
Figure 2.3 BEES Stakeholder Panel Importance Weights Synthesized across Voting Interest
And time Horizon 31
Figure 2.4 BEES Stakeholder Panel Importance Weights by Stakeholder Voting Interest. 32
Figure 2.5 BEES Stakeholder Panel Importance Weights by Time Horizon 32
Figure 2.6 BEES Study Periods for Measuring Building Product Environmental and
Economic Performance 34
Figure 2.7 Deriving the BEES Overall Performance Score 36
Figure 3.1 Concrete without Cement Substitutes System Boundaries 43
Figure 3.2 Concrete with Cement Substitutes System Boundaries 44
Figure 3.3 Lafarge North America Concrete Products System Boundaries 55
Figure 3.4 OSB Sheathing System Boundaries 59
Figure 3.5 Plywood Sheathing System Boundaries 64
Figure 3.6 CENTRIA Formawall Insulated Composite Panel System Boundaries 69
Figure 3.7 Brick and Mortar System Boundaries 73
Figure 3.8 Portland Cement Stucco System Boundaries 78
Figure 3.9 Masonry Cement Stucco System Boundaries 78
Figure 3.10 Aluminum Siding System Boundaries 83
Figure 3.11 Cedar Siding System Boundaries 88
Figure 3.12 Vinyl Siding System Boundaries 92
Figure 3.13 Headwaters Cement Products System Boundaries 97
Figure 3.14 Dryvit Outsulation System Boundaries 101
Figure 3.15 Dryvit Outsulation Plus System Boundaries 101
Figure 3.16 Cellulose Insulation System Boundaries 106
Figure 3.17 Fiberglass Insulation System Boundaries 110
Figure 3.18 Mineral Wool Insulation System Boundaries 114
Figure 3.19 Steel Framing System Boundaries 775
Figure 3.20 Wood Framing System Boundaries 720
Figure 3.21 SoyGuard System Boundaries 124
Figure 3.22 Asphalt Shingles System Boundaries 727
Figure 3.23 Clay Roof Tile System Boundaries 130
Figure 3.24 Fiber Cement Shingles System Boundaries 136
Figure 3.25 Gypsum Board System Boundaries 142
Figure 3.25aP&MPlastics Altree Panel System Boundaries 145
Figure 3.26 Trespa Composite Panels System Boundaries 149
Figure 3.27 Virgin Interior Latex Paint System Boundaries 753
Figure 3.28 Consolidated and Reprocessed Interior Latex Paint System Boundaries 753
Figure 3.29 Ceramic Tile System Boundaries 755
Figure 3.30 Linoleum Flooring System Boundaries 161
Figure 3.31 Vinyl Composition Tile System Boundaries 166
Figure 3.32 Composite Marble Tile System Boundaries 169
Figure 3.33 Terrazzo Flooring System Boundaries 773
Figure 3.34 Nylon Broadloom Carpet System Boundaries 176
XVll
-------
Figure 3.35 Nylon Carpet Tile System Boundaries 176
Figure 3.36 Wool Carpet System Boundaries 180
Figure 3.37ForboMarmoleum System Boundaries 184
Figure 3.38 UTTBroadloom Carpet System Boundaries 757
Figure 3.39 C&A ER3 Flooring Products System Boundaries 193
Figure 3.40 C&A Ethos Flooring Products System Boundaries 797
Figure 3.41 Bentley Prince Street Broadloom Carpet System Boundaries 194
Figure 3.42 InterfaceFLOR Carpet Tiles System Boundaries 795
Figure 3.43 J&J Certificate Broadloom Carpet System Boundaries 799
Figure 3.44 Mohawk Regents Row Broadloom Carpet System Boundaries 202
Figure 3.45 MohawkMeritage Broadloom Carpet System Boundaries 202
Figure 3.46 Natural Cork Parquet Floor Tile System Boundaries 205
Figure 3.47 Natural Cork Floating Floor Plank System Boundaries 206
Figure 3.48 Herman Miller Aeron Chair System Boundaries 209
Figure 3.49 Herman Miller Ambi Chair System Boundaries 272
Figure 3.50 Dustlock System Boundaries 216
Figure 3.51 Concrete Paving System Boundaries 279
Figure 3.52 Asphalt Paving with GSB88 Emulsified Sealer-Binder Maintenance
System Boundaries 223
Figure 3.53 Asphalt Paving with Traditional Maintenance System Boundaries 226
Figure 3.54 MicroStart 60 Fertilizer System Boundaries 230
Figure 3.55 Four All Seasons Fertilizer System Boundaries 233
Figure 3.56 Mineral Oil-Based Transformer Oil System Boundaries 236
Figure 3.57 Silicone-Based Transformer Oil System Boundaries 239
Figure 3.58 Envirotemp FR3 Dielectric Coolant System Boundaries 241
Figure 3.59 BIO TEMP Transformer Oil System Boundaries 244
Figure 3.60 Generic Biobased Transformer Oil System Boundaries 247
Figure 3.61 HOST Dry Carpet Cleaning System Boundaries 250
Figure 3.62 Nano Green System Boundaries 254
Figure 3.63 Green Solutions Glass Cleaner System Boundaries 255
Figure 3.64 Green Solutions Restroom Cleaner System Boundaries 261
Figure 3.65 VertecBio Gold System Boundaries 264
Figure 3.66 BEAN-e-doo Mastic Remover System Boundaries 267
Figure 4.1 Setting Analysis Parameters 272
Figure 4.2 Viewing Impact Category Weights 272
Figure 4.3 Entering User-Defined Weights 273
Figure 4.4 Selecting Building Elements for BEES Analysis 274
Figure 4.5 Selecting Building Product Alternatives 275
Figure 4.6 Setting Transportation Parameters 275
Figure 4.7 Selecting BEES Reports 277
Figure 4.8 Viewing BEES Overall Performance Results 275
Figure 4.9 Viewing BEES Environmental Performance Results 279
Figure 4.10 Viewing BEES Economic Performance Results 250
Figure 4.11 Viewing BEES Summary Table 253
Figure 4.12 Viewing BEES Environmental Impact Category Performance Results by
Life-Cycle Stage 284
XVlll
-------
Figure 4.13 Viewing BEES Environmental Impact Category Performance Results by Flow 255
Figure 4.14 Viewing BEES Embodied Energy Results 286
Figure 4.15 A Sampling of BEES "All Tables in One" Display 286
Figure 4.16 BEES Product Keyed to Environmental and Economic Performance Data
Codes 257
XIX
-------
XX
-------
1. Background and Introduction
Construction significantly alters the environment. According to the United Nations Environment
Programme,1 this industry sector consumes about half of the resources taken from nature
worldwide, including 25 % of the wood harvest. Mining, quarrying, drilling, and harvesting
these natural resources not only depletes them but pollutes the air and water, generates waste,
and accounts for biological diversity losses. Once acquired, transporting raw materials to
production facilities, then transforming them into building and construction products, generates
further pollution and requires considerable energy consumption with its associated greenhouse
gas emissions.
After production and transportation to a building site, many products generate waste at
installation. Others have relatively short useful lives, leading to frequent disposal and
manufacture of replacement products. Others contribute to unhealthy indoor air. Indoor pollutant
concentrations have been found to be twice to five times as high as those outdoors. Yet other
products influence building heating and cooling loads, largely responsible for building operating
energy use, which accounts for 40% of U.S. energy consumption. Worldwide, energy
consumption by the built environment is responsible for 40 % of greenhouse gas emissions.
Selecting environmentally preferable building products is one way to reduce the negative
environmental impacts associated with the built environment. However, while a 2006 poll by the
American Institute of Architects showed that 90 % of U.S. consumers would be willing to pay
more to reduce their home's environmental impact, they would pay only $4000 to $5000, or
about 2%, more.2 Thus, environmental performance must be balanced against economic
performance. Even the most environmentally conscious building product manufacturer or
designer will ultimately weigh environmental benefits against economic costs. To satisfy their
customers, manufacturers and designers need to develop and select building products with an
attractive balance of environmental and economic performance.
Identifying environmentally and economically balanced building products is not an easy task.
Today, the green building decisionmaking process is based on little credible, scientific data.
There is a great deal of interesting green building information available, so that in many respects
we know what to say about green buildings. However, we still do not routinely quantify and
synthesize the available information so that we know what to do in a way that is transparent,
defensible, and environmentally sound.
In this spirit, the U.S. National Institute of Standards and Technology (NIST) Healthy and
Sustainable Buildings Program began the Building for Environmental and Economic
Sustainability (BEES) project in 1994. The purpose of BEES is to develop and implement a
systematic methodology for selecting building products that achieve the most appropriate
balance between environmental and economic performance based on the decision maker's
1 United Nations Environment Programme, "Sustainable Building and Construction: Facts and Figures," Industry
and Environment: Sustainable Building and Construction, Vol. 26, No. 2-3, April-September 2003.
2 January 2006 survey cited in Washington Post, 8/6/06, p M3 (Green Buildings article by Sacha Cohen). %
-------
values. The methodology is based on consensus standards and is designed to be practical,
flexible, and transparent. The BEES model is implemented in publicly available decision-support
software, complete with actual environmental and economic performance data for a number of
building products. The intended result is a cost-effective reduction in building-related
contributions to environmental problems.
In 1997, the U.S. Environmental Protection Agency (EPA) Environmentally Preferable
Purchasing (EPP) Program began supporting the development of BEES for a number of years.
The EPP program is charged with carrying out Executive Order 13423, "Strengthening Federal
Environmental, Energy, and Transportation Management," which directs Executive agencies to
reduce the environmental burdens associated with the $230 billion in products and services they
purchase each year, including building products.
In 2002, the U.S. Department of Agriculture's Office of the Chief Economist, Office of Energy
Policy and New Uses, began supporting the development of BEES results for biobased products.
The 2002 Farm Bill authorized the creation of a program, known as BioPreferred, awarding
Federal purchasing preference to biobased products, which it defined as commercial or industrial
goods (other than food or feed) composed in whole or in significant part of biological products,
forestry materials, or renewable domestic agricultural materials, including plant, animal, or
marine materials. To address the questions of environmental and cost performance, candidate
biobased products are now required by federal rule to be evaluated by BEES, and performance
results shared with federal purchasers.3 With permission from manufacturers, building-related
biobased products evaluated to date under BioPreferred are included in BEES 4.0.
3 U.S. Department of Agriculture, Office of the Chief Economist, Office of Energy Policy and New Uses,
"Guidelines for Designating Biobased Products for Federal Procurement," Federal Register, 7 CFR Part 2902, Vol.
70, No. 7, January 11, 2005. For more information about BioPreferred, go to
http://www.biobased.oce.usda.gov/fb4p/aboutus.aspx.
-------
2. The BEES Model
The BEES methodology takes a multidimensional, life-cycle approach. That is, it considers
multiple environmental and economic impacts over the entire life of the building product.
Considering multiple impacts and life-cycle stages is necessary because product selection
decisions based on single impacts or stages could obscure others that might cause equal or
greater damage. In other words, a multidimensional, life-cycle approach is necessary for a
comprehensive, balanced analysis.
It is relatively straightforward to select products based on minimum life-cycle economic impacts
because building products are bought and sold in the marketplace. But how do we include life-
cycle environmental impacts in our purchase decisions? Environmental impacts such as global
warming, water pollution, and resource depletion are for the most part economic externalities.
That is, their costs are not reflected in the market prices of the products that generated the
impacts. Moreover, even if there were a mandate today to include environmental "costs" in
market prices, it would be nearly impossible to do so due to difficulties in assessing these
impacts in economic terms. How do you put a price on clean air and clean water? What is the
value of human life? Economists have debated these questions for decades, and consensus does
not appear likely.
While environmental performance cannot be measured on a monetary scale, it can be quantified
using the evolving, multi-disciplinary approach known as environmental life-cycle assessment
(LCA). The BEES methodology measures environmental performance using an LCA approach,
following guidance in the International Organization for Standardization (ISO) 14040 standard
for LCA.4 Economic performance is separately measured using the ASTM International standard
life-cycle cost (LCC) approach.5 These two performance measures are then synthesized into an
overall performance measure using the ASTM standard for Multiattribute Decision Analysis.6
For the entire BEES analysis, building products are defined and classified based on
UNIFORMAT II, the ASTM standard classification for building elements.7
2.1 Environmental Performance
Environmental life-cycle assessment is a "cradle-to-grave," systems approach for measuring
environmental performance. The approach is based on the belief that all stages in the life of a
4 International Organization for Standardization (ISO), Environmental Management—Life-Cycle Assessment-
Principles and Framework, International Standard 14040, 2006.
5 ASTM International, Standard Practice for Measuring Life-Cycle Costs of Buildings and Building Systems,
ASTM Designation E917-05, West Conshohocken, PA, 2005.
6 ASTM International, Standard Practice for Applying the Analytic Hierarchy Process to Multiattribute Decision
Analysis of Investments Related to Buildings and Building Systems, ASTM Designation E1765-02, West
Conshohocken, PA, 2002.
7 ASTM International, Standard Classification for Building Elements and Related Sitework—UNIFORMAT II,
ASTM Designation E1557-05, West Conshohocken, PA, 2005.
-------
product generate environmental impacts and must therefore be analyzed, including raw materials
acquisition, product manufacture, transportation, installation, operation and maintenance, and
ultimately recycling and waste management. An analysis that excludes any of these stages is
limited because it ignores the full range of upstream and downstream impacts of stage-specific
processes.
The strength of environmental life-cycle assessment is its comprehensive, multi-dimensional
scope. Many green building claims and strategies are now based on a single life-cycle stage or a
single environmental impact. A product is claimed to be green simply because it has recycled
content, or accused of not being green because it emits volatile organic compounds (VOCs)
during its installation and use. These single-attribute claims may be misleading because they
ignore the possibility that other life-cycle stages, or other environmental impacts, may yield
offsetting impacts. For example, the recycled content product may have a high embodied energy
content, leading to fossil fuel depletion, global warming, and acid rain impacts during the raw
materials acquisition, manufacturing, and transportation life-cycle stages. LCA thus broadens the
environmental discussion by accounting for shifts of environmental problems from one life-cycle
stage to another, or one environmental medium (land, air, water) to another. The benefit of the
LCA approach is in implementing a trade-off analysis to achieve a genuine reduction in overall
environmental impact, rather than a simple shift of impact.
The general LCA methodology involves four steps.8 The goal and scope definition step spells
out the purpose of the study and its breadth and depth. The inventory analysis step identifies and
quantifies the environmental inputs and outputs associated with a product over its entire life
cycle. Environmental inputs include water, energy, land, and other resources; outputs include
releases to air, land, and water. However, it is not these inputs and outputs, or inventory flows,
that are of primary interest. We are more interested in their consequences, or impacts on the
environment. Thus, the next LCA step, impact assessment, characterizes these inventory flows in
relation to a set of environmental impacts. For example, the impact assessment step might relate
carbon dioxide emissions, a flow, to global warming, an impact. Finally, the interpretation step
combines the environmental impacts in accordance with the goals of the LCA study.
2.1.1 Goal and Scope Definition
The goal of BEES LCAs is to generate environmental performance scores for building product
alternatives sold in the United States. These will be combined with economic performance scores
to help the building community select cost-effective, environmentally-preferred building
products.
The scoping phase of any LCA involves defining the boundaries of the product system under
study. The manufacture of any product involves a number of unit processes (e.g., ethylene
production for input to the manufacture of the styrene-butadiene bonding agent for stucco walls).
Each unit process involves many inventory flows, some of which themselves involve other,
subsidiary unit processes. The first product system boundary determines which unit processes
International Organization for Standardization (ISO), Environmental Management—Life-Cycle Assessment-
Principles and Framework, International Standard 14040, 2006.
-------
are included in the LCA. In the BEES system, the boundary-setting rule consists of a set of three
decision criteria. For each candidate unit process, mass and energy contributions to the product
system are the primary decision criteria. In some cases, cost contribution is used as a third
criterion.9 Together, these criteria provide a robust screening process, as illustrated in Figure 2.1,
showing how five ancillary materials (e.g., limestone used in portland cement manufacturing) are
selected from a list of nine candidate materials for inclusion in the LCA. A material must have a
large contribution to at least one decision criterion to be selected. The weight criterion selects
materials A, B, and C; the energy criterion adds material E; and cost flags material I. As a result,
the unit processes for producing ancillary materials A, B, C, E, and I are included in the system
boundaries.
Ancillary
material
Weight
Energy
Cost
(as a flag
when
necessar
Included in
system
boundaries?
negligible
contribution
small
contribution
large
contribution
Figure 2.1 Decision Criteria for Setting Product System Boundaries
The second product system boundary determines which inventory flows are tracked for in-
bounds unit processes. Quantification of all inventory flows is not practical for the following
reasons:
An ever-expanding number of inventory flows can be tracked. For instance, including the
U.S. Environmental Protection Agency's Toxic Release Inventory (TRI) data would result in
tracking approximately 200 inventory flows arising from polypropylene production alone.
9 While a large cost contribution does not directly indicate a significant environmental impact, it may indicate
scarce natural resources or numerous subsidiary unit processes potentially involving high energy consumption.
-------
Similarly, including radionucleide emissions generated from electricity production would
result in tracking more than 150 flows. Managing such large inventory flow lists adds to the
complexity, and thus the cost, of carrying out and interpreting the LCA.
• Attention should be given in the inventory analysis step to collecting data that will be useful
in the next LCA step, impact assessment. By restricting the inventory data collection to the
flows actually needed in the subsequent impact assessment, a more focused, higher quality
LCA can be carried out.
Therefore, in the BEES model, a focused, cost-effective set of inventory flows is tracked,
reflecting flows that the U.S. EPA Office of Research and Development has deemed important in
the subsequent impact assessment step.10
Defining the unit of comparison is another important task in the goal and scoping phase of LCA.
The basis for all units of comparison is the functional unit, defined so that the products compared
are true substitutes for one another. In the BEES model, the functional unit for most building
0 0
products is 0.09 m (1 ft ) of product service for 50 years. For example, the functional unit for
the BEES floor covering alternatives is covering 0.09 m2 (1 ft2) of floor surface for 50 years. The
following BEES product categories have different functional units:
• Roof Coverings: Covering 9.29 m2 (1 square, or 100 ft2) of roof surface for 50 years
• Concrete Beams and Columns: 0.76 m3 (1 yd3) of product service for 50 years
• Office Chairs: Seating for 1 person for 50 years
• Adhesive and Mastic Remover: Removing 9.29 m2 (100 ft2) of mastic under vinyl or similar
flooring over 50 years
• Exterior Sealers and Coatings: Sealing or coating 9.29 m2 (100 ft2) of exterior surface over
50 years
• Transformer Oils: Cooling for one 1 000 kV-A transformer for 30 years
• Fertilizer: Fertilizing 0.40 ha (1 acre) for 10 years
• Carpet Cleaners: Cleaning 92.9 m2 (1 000 ft2) of carpet once
• Floor Stripper: Removing three layers of wax and one layer of sealant from 9.29 m2 (100 ft2)
of hardwood flooring once
• Roadway Dust Control: Controlling dust from 92.9 m2 (1 000 ft2) of surface area once
• Bath and Tile Cleaner: Using 3.8 L (1 gal) of ready-to-use cleaner once
• Glass Cleaners: Using 3.785 m3 (1 000 gal) of ready-to-use glass cleaner once11
• Grease and Graffiti Remover: Using 3.8 L (1 gal) of grease and graffiti remover once
For three building elements—roof coverings, wall insulation, and exterior wall finishes—
functional units may be further specified to account for important factors affecting their
influence on building heating and cooling loads (e.g., local climate, fuel type). Otherwise, all
product alternatives are assumed to meet minimum technical performance requirements (e.g.,
10 U.S. Environmental Protection Agency, Tool for the Reduction and Assessment of Chemical and Other
Environmental Impacts (TRACI): User's Guide and System Documentation, EPA/600/R-02/052, U.S. EPA Office
of Research and Development, Cincinnati, OH, August 2002.
11 While it is unrealistic to assume a need for such a large quantity at a given time, this amount is used so that the
environmental impacts for the product are large enough to be reported in the BEES results.
-------
acoustic and fire performance). The functional unit provides the critical reference point to which
all inventory flows are scaled.
Scoping also involves setting data requirements. Data requirements for the BEES study include:
• Geographic coverage: The data are U.S. average data.
• Time period coverage: The data are a combination of data collected specifically for BEES
4.0 within the last two years and data from the new, critically-reviewed U.S. LCI Database,
developed using a common, ISO 14040-consistent research protocol.12
• Technology coverage: For generic products, the most representative technology is evaluated.
When data for the most representative technology are not available, an aggregated result is
developed based on the U.S. average technology for that industry.
2.1.2 Inventory Analysis
Inventory analysis entails quantifying the inventory flows for a product system. Inventory flows
include inputs of water, energy, and raw materials, and releases to air, land, and water. Data
categories are used to group inventory flows in LCAs. For example, in the BEES model, flows
such as aldehydes, ammonia, and sulfur oxides are grouped under the air emissions data
category. Figure 2.2 shows the categories under which data are grouped in the BEES system.
Refer to the BEES environmental performance data files, accessible through the BEES software,
for a detailed listing of the 504 inventory flow items included in BEES.
- Energy -
-Water -
Raw Materials
I
Unit
Process
—Air Emissions —
-Water Effluents -
-Releases to Land-
- Other Releases-
Intermediate Material
or Final Product
Figure 2.2 BEES Inventory Data Categories
A number of approaches may be used to collect inventory data for LCAs. These range from:13
U.S. Department of Energy, National Renewable Energy Laboratory, U.S. Life-Cycle Inventory Database,
'/www.nrel.gov/lci/.
U.S. Environmental Protection Agency, Office of Research and Dev
Inventory Guidelines and Principles, EPA/600/R-92/245, February 1993.
http://www.nrel.gov/lci/.
13 U.S. Environmental Protection Agency, Office of Research and Development, Life Cycle Assessment:
1
-------
• Unit process- and facility-specific: collect data from a particular process within a given
facility that are not combined in any way
• Composite: collect data from the same process combined across locations
• Aggregated: collect data combining more than one process
• Industry-average: collect data derived from a representative sample of locations believed to
statistically describe the typical process across technologies
• Descriptive: collect data whose representation may be unknown but which are qualitatively
descriptive of a process
Since the goal of BEES LCAs is to generate U.S. average results, generic product data are
primarily collected using the industry-average approach. Manufacturer-specific product data are
primarily collected using the unit process- and facility-specific approach, then aggregated to
preserve manufacturer confidentiality. Data collection for BEES 4.0 was done under contract
with Four Elements, LLC and First Environment, Inc. using the Simapro LCA software. These
data represent the closest approximations currently available of the burdens associated with the
production, use, and disposal of BEES products. For generic products, assumptions regarding the
associated unit processes were verified through experts in the appropriate industries to assure the
data were correctly incorporated in BEES. For manufacturer-specific products, a U.S. Office of
Management and Budget-approved BEES Please Questionnaire was completed by manufacturers
to collect inventory data from their manufacturing plant(s); these data were validated by Four
Elements, then associated upstream and downstream data added to yield cradle-to grave
inventories. For more information about the BEES Please program, visit
http://www.bfrl.nist.gov/oae/software/bees/please/bees_please.html.
2.1.3 Impact Assessment
The impact assessment step of LCA quantifies the potential contribution of a product's inventory
flows to a range of environmental impacts. There are several well-known LCA impact
assessment approaches.
2.1.3.1 Impact Assessment Methods
Direct Use of Inventories. In the most straightforward approach to LCA, the impact assessment
step is skipped, and the life cycle inventory results are used as-is in the final interpretation step
to help identify opportunities for pollution prevention or increases in material and energy
efficiency for processes within the life cycle. However, this approach in effect gives the same
weight to all inventory flows (e.g., to the reduction of carbon dioxide emissions and to the
reduction of lead emissions). For most impacts, equal weighting of flows is unrealistic.
Critical Volumes (Switzerland). The "weighted loads" approach, better known as the Swiss
Critical Volume approach, was the first method proposed for aggregating inventory flow data.14
14 K. Habersatter, Ecobalance of Packaging Materials - State of 1990, Swiss Federal Office of Environment,
Forests, and Landscape, Bern, Switzerland, February 1991, and Bundesamt fur Umweltschutz, Oekobilanzen von
Packstoffen, Schriftenreihe Umweltschutz 24, Bern, Switzerland, 1984.
-------
The critical volume for a substance is a function of its load and its legal limit. Its load is the total
quantity of the flow per unit of the product. Critical volumes can be defined for air and water,
and in principle also for soil and groundwater, providing there are legal limit values available.
This approach has the advantage that long lists of inventory flows, especially for air and water,
can be aggregated by summing the critical volumes for the individual flows within the medium
being considered—air, water, or soil. However, the Critical Volume approach has been
abandoned for the following reasons:
• Fate and exposure are not considered.
• The underlying assumption that the residual risk at threshold levels is the same for all
substances does not hold.15
• Legal limit values are available only for certain chemicals and pollutants. Long-term global
effects such as global warming are excluded since there are no universal legal limits for the
chemicals involved.
Ecological Scarcity (Switzerland). A more general approach has been developed by the Swiss
Federal Office for the Environment (FOEN) and applied to Switzerland, Sweden, Belgium, The
Netherlands, and Germany.16 With this approach, "Eco-Points" are calculated for a product,
using the "Eco-Factor" determined for each inventory flow. Eco-Factors are based on current
annual flows relative to target maximum annual flows for the geographic area considered. The
Eco-Points for all inventory flows are added together to give one single, final measure of impact.
The concept used in this approach is appealing but has the following difficulties:
• It is valid only in a specific geographical area.
• Estimating target flows can be a difficult and time-consuming exercise.
• The underlying assumption that the residual risk at target levels is the same for all substances
does not hold.17
• The scientific calculation of environmental impacts is combined with political and subjective
judgment, or valuation. The preferred approach is to separate the science from the valuation.
Environmental Priorities System (Sweden). The Environmental Priority Strategies in Product
Development System, the EPS System, was developed by the Swedish Environmental Research
Institute.18 It takes an economic approach to assessing environmental impacts. The basis for the
evaluation is the Environmental Load Unit, which corresponds to the willingness to pay 1
15 M.A. Curran et al., BEES 2.0, Building for Environmental and Economic Sustainability: Peer Review Report,
NISTIR 6865, Washington, DC, 2002.
16 R. Frischknecht et. al, "Swiss Ecological Scarcity Method: The New Version 2006," Berne, Switzerland,
2006.
17 M.A. Curran etal, 2002.
18 B. Steen, A Systematic Approach to Environmental Priority Strategies in Product Development (EPS). Version
2000, CPM Report 1999:4 and 5, CPM, Chalmers University, Goteborg 1999.
-------
European Currency Unit. The final result of the EPS system is a single number summarizing all
environmental impacts, based on:
• Society's judgment of the importance of each environmental impact.
• The intensity and frequency of the impact.
• Location and timing of the impact.
• The contribution of each flow to the impact in question.
• The cost of decreasing each inventory flow by one weight unit.
The EPS system combines indices of ecological, sociological, and economic effects to give a
total effect index for each flow. The total effect index is multiplied by the amount of the flow to
give the "environmental load unit." Although this methodology is popular in Sweden, its use is
criticized due to its lack of transparency and the quantity and quality of the model's underlying
assumptions.
Eco-Indicator 99. The Eco-Indicator 99 method is a "damage-oriented" approach to life cycle
impact assessment that has been developed in The Netherlands by Pre Consultants.19 It is
appealing for its emphasis on simplifying the subsequent life cycle assessment step, namely,
weighting of the relative importance of environmental impacts. To this end, a very limited
number of environmental damage categories, or "endpoints," are evaluated: Human Health,
Ecosystem Quality, and Resources. Damage models are used to evaluate products in relation to
these three impact categories. While the Eco-Indicator 99 method offers promise for the future, it
has been criticized to date due to the many assessment gaps in the underlying damage models. In
addition, the approach has a European focus at present.
Environmental Problems. The Environmental Problems approach to impact assessment was
developed within the Society for Environmental Toxicology and Chemistry (SETAC). It
involves a two-step process:20'21'22'23
• Classification of inventory flows that contribute to specific environmental impacts. For
example, greenhouse gases such as carbon dioxide, methane, and nitrous oxide are classified
as contributing to global warming.
• Characterization of the potential contribution of each classified inventory flow to the
corresponding environmental impact. This results in a set of indices, one for each impact,
that is obtained by weighting each classified inventory flow by its relative contribution to the
impact. For instance, the Global Warming Potential index is derived by expressing each
contributing inventory flow in terms of its equivalent amount of carbon dioxide.
19 M. Goedkoop and R. Spriensma, The Eco-indicator '99: A Damage Oriented Method for Life Cycle Impact
Assessment, VROM Zoetermeer, Nr. 1999/36A/B, 2nd edition, April 2000.
20 Guinea et al, LCA -An operational guide to the ISO-standards, CML, Leiden, The Netherlands, 2001.
21 SETAC-Europe, Life Cycle Assessment, B. DeSmet, et al. (eds), 1992.
22 SETAC, A Conceptual Framework for Life Cycle Impact Assessment, J. Fava, etal. (eds), 1993.
23 SETAC, Guidelines for Life Cycle Assessment: A "Code of Practice, " F. Consoli, et al. (eds), 1993.
10
-------
The Environmental Problems approach does not offer the same degree of relevance for all
environmental impacts. For global and regional effects (e.g., global warming and acidification)
the method may result in an accurate description of the potential impact. For impacts dependent
upon local conditions (e.g., smog, ecological toxicity, and human health) it may result in an
oversimplification of the actual impacts because the indices are not tailored to localities. Another
drawback of this method is the unclear environmental importance of the impacts, making the
subsequent weighting step difficult.
2.1.3.2 Characterizing Impacts in BEES
The BEES model uses the Environmental Problems approach where possible because it enjoys
some general consensus among LCA practitioners and scientists.24 The U.S. EPA Office of
Research and Development has developed TRACT (Tool for the Reduction and Assessment of
Chemical and other environmental Impacts), a set of state-of-the-art, peer-reviewed U.S. life
cycle impact assessment methods that has been adopted in BEES 4.O.25 Ten of the 11 TRACT 1.0
impacts follow the Environmental Problems approach: Global Warming Potential, Acidification
Potential, Eutrophication Potential, Fossil Fuel Depletion, Habitat Alteration, Criteria Air
Pollutants, Human Health, Smog, Ozone Depletion, and Ecological Toxicity. Water Intake, the
eleventh impact, is assessed in TRACT 1.0 using the Direct Use of Inventories Approach. BEES
also assesses Indoor Air Quality, an impact not included in TRACI because it is somewhat
unique to the building industry. Indoor Air Quality is assessed using the Direct Use of
Inventories approach, for a total of 12 impacts for all BEES products. Note that some flows
characterized by TRACI did not have exact matches in the Simapro LCA software used to
develop life cycle inventories for BEES. Where discrepancies were found, a significance
analysis was conducted to assess the relevance of the mismatched flows. Proxy flows or
alternative characterization factors were developed for those mismatched flows found to be
relevant, and validated with TRACI developers.
If the BEES user has important knowledge about other potential environmental impacts, it
should be brought into the interpretation of the BEES results. The twelve BEES impacts are
discussed below.
Global Warming Potential. The Earth absorbs radiation from the Sun, mainly at the surface.
This energy is then redistributed by the atmosphere and ocean and re-radiated to space at longer
wavelengths. Some of the thermal radiation is absorbed by "greenhouse" gases in the
atmosphere, principally water vapor, but also carbon dioxide, methane, the chlorofluorocarbons,
and ozone. The absorbed energy is re-radiated in all directions, downwards as well as upwards,
such that the radiation that is eventually lost to space is from higher, colder levels in the
atmosphere. The result is that the surface loses less heat to space than it would in the absence of
the greenhouse gases and consequently stays warmer than it would be otherwise. This
24 SETAC, Life-Cycle Impact Assessment: The State-of-the-Art, J. Owens, et al. (eds), 1997.
25 U.S. Environmental Protection Agency, Tool for the Reduction and Assessment of Chemical and Other
Environmental Impacts (TRACI): User's Guide and System Documentation, EPA/600/R-02/052, U.S. EPA Office
of Research and Development, Cincinnati, OH, August 2002. For a detailed discussion of the TRACI methods, see
J.C. Bare et al, "TRACI: The Tool for the Reduction and Assessment of Chemical and other environmental
Impacts," Journal of Industrial Ecology, Vol. 6, No. 3-4, 2003.
11
-------
phenomenon, which acts rather like a 'blanket' around the Earth, is known as the greenhouse
effect.
The greenhouse effect is a natural phenomenon. The environmental issue is the change in the
greenhouse effect due to emissions (an increase in the effect) and absorptions (a decrease)
attributable to humans. A general increase in temperature can alter atmospheric and oceanic
temperatures, which can potentially lead to alteration of circulation and weather patterns. A rise
in sea level is also predicted from an increase in temperature due to thermal expansion of the
oceans and melting of polar ice sheets.
Global Warming Potentials, or GWPs, have been developed to characterize the change in the
greenhouse effect due to emissions and absorptions attributable to humans. LCAs commonly
use those GWPs representing a 100-year time horizon. GWPs permit computation of a single
index, expressed in grams of carbon dioxide per functional unit of a product, which measures
the quantity of carbon dioxide with the same potential for global warming over a 100-year
period:
global warming index = Z; ni; x GWP;, where
mi= mass (in grams) of inventory flow i, and
GWP; = grams of carbon dioxide with the same heat trapping potential over 100 years as
one gram of inventory flow i, as listed in Table 2.1. 26
Table 2.1 BEES Global Warming Potential Characterization Factors
GWPi
Flow (i) (CO 2-
equivalents)
Carbon Dioxide (CO2, net) 1
Carbon Tetrachloride (CC14) 1800
Carbon Tetrafluoride (CF4) 5700
CFC 12 (CC12F2) 10 600
Chloroform (CHC13, HC-20) 30
Halon 1301 (CF3Br) 6900
HCFC 22 (CHF2C1) 1700
Methane (CH4) 23
Methyl Bromide (CH3Br) 5
Methyl Chloride (CH3C1) 16
Methylene Chloride (CH2C12, HC-130) 10
Nitrous Oxide (N2O) 296
Trichloroethane (1,1,1-CH3CC13) 140
' U.S. Environmental Protection Agency, TRACI, 2003.
12
-------
Acidification Potential. Acidifying compounds may in a gaseous state either dissolve in water
or fix on solid particles. They reach ecosystems through dissolution in rain or wet deposition.
Acidification affects trees, soil, buildings, animals, and humans. The two compounds
principally involved in acidification are sulfur and nitrogen compounds. Their principal human
source is fossil fuel and biomass combustion. Other compounds released by human sources,
such as hydrogen chloride and ammonia, also contribute to acidification.
Characterization factors for potential acid deposition onto the soil and in water have been
developed like those for the global warming potential, with hydrogen ions as the reference
substance. These factors permit computation of a single index for potential acidification (in
grams of hydrogen ions per functional unit of product), representing the quantity of hydrogen
ion emissions with the same potential acidifying effect:
acidification index = Z; ni; * AP;, where
m; = mass (in grams) of inventory flow i, and
AP; = millimoles of hydrogen ions with the same potential acidifying effect as one gram
of inventory flow i, as listed in Table 2.2.27
Table 2.2 BEES Acidification Potential Characterization Factors
(Hydrogen-Ion
Flow (i) Equivalents)
Ammonia (NH3) 95.49
Hydrogen Chloride (HC1) 44.70
Hydrogen Cyanide (HCN) 60.40
Hydrogen Fluoride (HF) 81.26
Hydrogen Sulfide (H2S) 95.90
Nitrogen Oxides (NOX as NO2) 40.04
Sulfur Oxides (SOX as SO2) 50.79
Sulfuric Acid (H2SO4) 33.30
Eutrophication Potential. Eutrophication is the addition of mineral nutrients to the soil or water.
In both media, the addition of large quantities of mineral nutrients, such as nitrogen and
phosphorous, results in generally undesirable shifts in the number of species in ecosystems and a
reduction in ecological diversity. In water, it tends to increase algae growth, which can lead to
lack of oxygen and therefore death of species like fish.
ibid.
13
-------
Characterization factors for potential eutrophication have been developed like those for the
global warming potential, with nitrogen as the reference substance. These factors permit
computation of a single index for potential eutrophication (in grams of nitrogen per functional
unit of product), representing the quantity of nitrogen with the same potential nullifying effect:
eutrophication index = Z; ni; x EP;, where
m; = mass (in grams) of inventory flow i, and
EP; = grams of nitrogen with the same potential nullifying effect as one gram of
inventory flow i, as listed in Table 2.3.28
Table 2.3 BEES Eutrophication Potential Characterization Factors
EPi
(nitrogen-
Flow ft) equivalents)
Ammonia (NH3) 0.12
Nitrogen Oxides (NOX as NO2) 0.04
Nitrous Oxide (N2O) 0.09
Phosphorus to air (P) 1.12
Ammonia (NH4+, NH3, as N) 0.99
BODS (Biochemical Oxygen Demand) 0.05
COD (Chemical Oxygen Demand) 0.05
Nitrate (NO3~) 0.24
Nitrite (NO2~) 0.32
Nitrogenous Matter (unspecified, as N) 0.99
Phosphates (PO43", HPO42", H2PO4", 7.29
H3PO4, as P)
Phosphorus to water (P) 7.29
Fossil Fuel Depletion. Some experts believe fossil fuel depletion is fully accounted for in
market prices. That is, market price mechanisms are believed to take care of the scarcity issue,
price being a measure of the level of depletion of a resource and the value society places on that
depletion. However, price is influenced by many factors other than resource supply, such as
resource demand and non-perfect markets (e.g., monopolies and subsidies). Furthermore, fossil
fuel depletion is at the heart of the sustainability debate.
Fossil fuel depletion is included in the TRACT set of impact assessment methods adopted by
BEES 4.0. It is important to recognize that this impact addresses only the depletion aspect of
fossil fuel extraction, not the fact that the extraction itself may generate impacts. Extraction
impacts, such as methane emissions from coal mining, are addressed in other impacts, such as
global warming.
28 ibid.
14
-------
To assess fossil fuel depletion, TRACT follows the approach developed for the Eco-Indicator 99
method, which measures how the amount of energy required to extract a unit of energy for
consumption changes over time. Characterization factors have been developed permitting
computation of a single index for potential fossil fuel depletion—in surplus megajoules (MJ) per
functional unit of product—and assess the surplus energy requirements from the consumption of
fossil fuels:
fossil fuel depletion index = Z; c; x FP;, where
c; = consumption (in kg) of fossil fuel i, and
FP; = MJ input requirement increase per kilogram of consumption of fossil fuel i, as
listed in Table 2.4.29
Table 2.4 BEES Fossil Fuel Depletion Potential Characterization Factors
FPi
Flow (i) (surplus MJ/kg)
Coal (in ground) 0.25
Natural Gas (in ground) 7.80
Oil (in ground) 6.12
While uranium is a major source of energy in the United States, it is not, at present, included in
the TRACT assessment of the depletion of nonrenewable fuel resources. As impact assessment
science continues to evolve over time, it is hoped that uranium will become part of that
assessment. Future versions of BEES will incorporate improved impact assessment methods as
they become available.
Indoor Air Quality. Indoor air quality impacts are not included in traditional life-cycle impact
assessments. Most LCAs conducted to date have been applied to relatively short-lived, non-
building products (e.g., paper and plastic bags), for which indoor air quality impacts are not an
important issue. However, the indoor air performance of building products is of particular
concern to the building community and should be explicitly considered in any building product
LCA.
Ideally, characterization factors would be available for indoor air pollutants as they are for other
flows such as global warming gases. However, there is little scientific consensus about the
relative contributions of pollutants to indoor air performance. In the absence of reliable
characterization factors, a product's total volatile organic compound (VOC) emissions are often
used as a measure of its indoor air performance. Note that a total VOC measure equally weights
the contributions of the individual compounds that make up the measure. Also, reliance on
VOC emissions alone may be misleading if other indoor air contaminants, such as particulates,
aerosols, and mold, are also present. Finally, total VOC measures are highly dependent on the
29 U.S. Environmental Protection Agency, TRACI, 2003.
15
-------
analytical method used and there is no single analytical method than can measure the entire
range of VOCs, rendering the term "total" somewhat misleading.
Indoor air quality is assessed for the following building elements currently covered in BEES:
floor coverings, interior wall finishes, chairs, carpet cleaners, glass cleaners, bath and tile
cleaner, floor stripper, and adhesive and mastic remover.30 Recognizing the inherent limitations
from using total VOCs to assess indoor air quality performance, estimates of total VOC
emissions are used as a proxy measure. The total VOC emissions over an initial number of h
(e.g., for floor coverings, combined product and adhesive emissions over the first 72 h) is
multiplied by the number of times over the product category's use period those "initial h" will
occur (to account for the possibility of product replacements), to yield an estimate of total VOC
emissions per functional unit of product. The result is entered into the life cycle inventory for the
product, and used directly to assess the indoor air quality impact. The rationale for this particular
approach is that VOC emissions are at issue for a limited period of time after installation. The
more installations required then, the greater the indoor air quality impact.
Indoor air quality is discussed in the context of sheathing and insulation products. Sheathing
products are often made of wood, which is of concern for its formaldehyde emissions.
Formaldehyde is thought to affect human health, especially for people with chemical sensitivity.
Composite wood products using urea-formaldehyde adhesives have higher formaldehyde
emissions than those using phenol-formaldehyde adhesives, and different composite wood
products have different levels of emissions. Composite wood products include oriented strand
board (OSB) and softwood plywood, both included as sheathing products in BEES. Most OSB is
now made using a methylene diphenylisocyanate (MDI) binder, and is modeled as such in
BEES. OSB using an MDI binder emits no formaldehyde other than the insignificant amount
naturally occurring in the wood itself.31 Softwood plywood also has extremely low indoor
formaldehyde emissions because it uses phenol-formaldehyde binders and because it is used
primarily on the exterior shell of buildings.32 Thus, assuming formaldehyde emission is the only
significant indoor air concern for wood products, neither of the two composite wood products as
modeled in BEES are thought to significantly affect indoor air quality.
Indoor air quality is also an issue for insulation products. The main issues are the health impacts
of fibers, hazardous chemicals, and particles released from some insulation products. These
releases are the only insulation-related indoor air issues considered in BEES. As a result of its
listing by the International Agency for Research on Cancer as a "possible carcinogen," fiberglass
products are now required to have cancer warning labels. The fiberglass industry has responded
by developing fiberglass products that reduce the amount of loose fibers escaping into the air.
For cellulose products, there are claims that fire retardant chemicals and respirable particles are
hazardous to human health. Mineral wool is sometimes claimed to emit fibers and chemicals that
30 While indoor air quality is considered for glass cleaners and bath and tile cleaner, manufacturers of all
products currently in these categories, all of whom produce biobased products, report zero VOC emissions during
their use. Indoor air quality data provided by manufacturers of products in the grease and graffiti remover category
is incompatible; as a result, indoor air quality is not assessed for this category.
31 Alex Wilson and Nadav Malin, "The IAQ Challenge: Protecting the Indoor Environment," Environmental
Building News, Vol. 5, No. 3, May/June 1996, p 15.
32 American Institute of Architects, Environmental Resource Guide, Plywood Material Report, May 1996.
16
-------
could be health irritants. For all these products, however, there should be little or no health risks
to building occupants if they are installed in accordance with manufacturers' recommendations.
Assuming proper installation, then, none of these products as modeled in BEES are thought to
significantly affect indoor air quality.33
All other BEES building elements are primarily exterior elements, or interior elements made of
inert materials, for which indoor air quality is not an issue.
Note that due to limitations in indoor air science, the BEES indoor air performance scores
are based on heuristics. If the BEES user has better knowledge about indoor air performance, it
should be brought into the interpretation of the results.
Habitat Alteration. The habitat alteration impact measures the potential for land use by humans
to lead to damage of Threatened and Endangered (T&E) Species. In TRACI 1.0, the set of U.S.
impact assessment methods adopted in BEES, the density of T&E Species is used as a proxy for
the degree to which the use of land may lead to undesirable changes in habitats. Note that this
approach does not consider the original condition of the land, the extent to which human activity
changes the land, or the length of time required to restore the land to its original condition. As
impact assessment science continues to evolve, it is hoped that these potentially important
factors will become part of the habitat alteration assessment. Future versions of BEES will
incorporate improved habitat alteration assessment methods as they become available.
Inventory data are not readily available for habitat alteration assessment across all life cycle
stages; the use and end-of-life stages offer the only reliable inventory data for this impact to date.
These two stages, though, may be the most important life cycle stages for habitat alteration
assessment due to their contributions to landfills. Indeed, an informal evaluation of two interior
wall products found that post-consumer landfill use accounted for more than 80 % of the total
habitat alteration impact for both products. In BEES, habitat alteration is assessed at the use and
end of life stages only, based on the landfilled waste (adjusted for current recycling practices)
from product installation, replacement, and end of life. Future versions of BEES will incorporate
more life cycle stages as consistent inventory data become available.
Characterization factors have been developed permitting computation of a single index for
potential habitat alteration, expressed in T&E Species count per functional unit of product:
habitat alteration index = Z; a; x TED, where
a; = surface area (in m2 disrupted) of land use flow i, and
TED = U.S. T&E Species density (in T&E Species count per m2), as listed in Table 2.5.
34
33 Alex Wilson, "Insulation Materials: Environmental Comparisons," Environmental Building News, Vol. 4, No.
1, January/February 1995, pp. 15-16
34U.S. Environmental Protection Agency, TRACI, 2003.
17
-------
Table 2.5 BEES Habitat Alteration Potential Characterization Factors
TED
Flow (i) (T&E count/m2)
Land Use (Installation Waste) 6.06E-10
Land Use (Replacement Waste) 6.06E-10
Land Use (End-of-Period Waste) 6.06E-10
Water Intake. Water resource depletion has not been routinely assessed in LCAs to date, but
researchers are beginning to address this issue to account for areas where water is scarce, such as
the Western United States. It is important to recognize that this impact addresses only the
depletion aspect of water intake, not the fact that activities such as agricultural production and
product manufacture may generate water pollution. Water pollution impacts, such as nitrogen
runoff from agricultural production, are addressed in other impacts, such as eutrophication.
In TRACI 1.0, the set of U.S. impact assessment methods adopted in BEES, the Direct Use of
Inventories approach is used to assess water resource depletion. Water intake from cradle to
grave is recorded in the BEES life cycle inventory for each product (in liters per functional unit),
and is used directly to assess this impact.
Criteria Air Pollutants. Criteria air pollutants are solid and liquid particles commonly found in
the air. They arise from many activities including combustion, vehicle operation, power
generation, materials handling, and crushing and grinding operations. They include coarse
particles known to aggravate respiratory conditions such as asthma, and fine particles that can
lead to more serious respiratory symptoms and disease.35
Disability-adjusted life years, or DALYs, have been developed to measure health losses from
outdoor air pollution. They account for years of life lost and years lived with disability, adjusted
for the severity of the associated unfavorable health conditions. TRACI characterization factors
permit computation of a single index for criteria air pollutants, with disability-adjusted life years
(DALYs) as the common metric:
criteria air pollutants index = Z; ni; x CP;, where
nii= mass (in grams) of inventory flow i, and
CP; = microDALYs per gram of inventory flow i, as listed in Table 2.6.36
35 ibid.
36 ibid.
18
-------
Table 2. 6 BEES Criteria Air Pollutant Characterization Factors
Flow (i) (microDALYs/g)
Nitrogen Oxides (NOX as NO2) 0.002
Parti culates (>PM10) 0.046
Parti culates (<=PM 10) 0.083
Particulates (unspecified) 0.046
Sulfur Oxides (SOX as SO2) _ 0.014
Human Health. There are many potential human health effects from exposure to industrial and
natural substances, ranging from transient irritation to permanent disability and even death.
Some substances have a wide range of different effects, and different individuals have widely
varying tolerances to different substances. BEES adopts and extends the TRACT 1.0 approach to
evaluating human health impacts. Note that this approach does not include occupational health
effects.
TRACT developers have computed Toxicity Equivalency Potentials (TEPs), which are
characterization factors measuring the relative health concern associated with various chemicals
from the perspective of a generic individual in the United States. For cancer effects, the TRACT
system's TEPs are expressed in terms of benzene equivalents, while for noncancer health effects
they are denominated in toluene equivalents. In order to synthesize all environmental impacts in
the next LCA step (interpretation), however, BEES requires a combined measure of cancer and
noncancer health effects because three of its four impact importance weight sets are available
only at the combined level. The BEES 2.0 Peer Review Team suggested that to address this
need, threshold levels for toluene and benzene be obtained from the developers of the TRACT
TEPs and be given equal importance in combining cancer and noncancer health effects.37
Threshold levels were thus obtained and used to develop a ratio converting benzene equivalents
to toluene equivalents (21 000 kg toluene/kg benzene).38
The "extended" TRACT characterization factors permit computation of a single index for
potential human health effects (in grams of toluene per functional unit of product), representing
the quantity of toluene with the same potential human health effects:
human health index = Z; ni; x HP;, where
m; = mass (in grams) of inventory flow i, and
HP; = grams of toluene with the same potential human health effects as one gram of
inventory flow i.
37 M.A. Currane/a/., BEES 2.0, Building for Environmental and Economic Sustainability: Peer Review Report,
2002.
36Personal correspondence with Edgar Hertwich, International Institute for Applied Systems Analysis,
Laxenburg, Austria, 6/20/2002.
19
-------
There are more than 200 flows included in the BEES human health impact assessment. A
sampling of the most important of these flows and their characterization factors are reported in
Table 2.7, sorted in descending order of toluene equivalents.39 Flows to air are preceded with the
designation "(a)" and flows to water with the designation "(w)."
As discussed in section 2.1.4, NIST convened a BEES Stakeholder Panel in May 2006 to
develop a new impact importance weight set for BEES 4.0. To permit a more refined human
health impact assessment, the panel judged the importance of cancer and noncancer human
health effects separately. If the BEES user chooses to interpret its LCA results using the
Stakeholder Panel weight set, the cancer-related flows are assessed in terms of benzene
equivalents. To view the human health cancer flows and their benzene-based characterization
factors, open the file EQUIV12.DBF under the File/Open menu item in the BEES software.
Smog Formation Potential. Under certain climatic conditions, air emissions from industry and
transportation can be trapped at ground level, where they react with sunlight to produce
photochemical smog. One of the components of smog is ozone, which is not emitted directly,
but rather produced through the interactions of volatile organic compounds (VOCs) and oxides
of nitrogen (NOX). Smog leads to harmful impacts on human health and vegetation. In BEES, the
smog impact does not account for indoor VOCs that make their way outdoors. Rather, indoor
VOCs are evaluated under the BEES Indoor Air Quality impact.
Characterization factors for potential smog formation have been developed for the TRACI set of
U.S. impact assessment methods, with nitrogen oxides as the reference substance. These factors
permit computation of a single index for potential smog formation (in grams of nitrogen oxides
per functional unit of product), representing the quantity of nitrogen oxides with the same
potential for smog formation:
39 U.S. Environmental Protection Agency, TRACI, 2003. As discussed, TRACI benzene equivalents have been
converted to toluene equivalents.
20
-------
Table 2. 7 Sampling of BEES Human Health Characterization Factors
(toluene-
Flow (i) _ equivalents)
Cancer-(a) Dioxins (unspecified) 38 292 661 685 580
Noncancer-(a) Dioxins (unspecified) 2 286 396 218 965
Cancer-(a) Diethanol Amine (C4HnO2N) 2 532 000 000
Cancer-(a) Arsenic (As) 69 948 708
Cancer--(a) BenzoCancer— (a)pyrene (C2oHi2) 34 210 977
Noncancer-(a) Mercury (Hg) 19255 160
Noncancer-(w) Mercury (Hg+, Hg++) 18917511
Cancer-(a) Carbon Tetrachloride (CC14) 17 344 285
Cancer-(w) Arsenic (As3+, As5+) 1 7 2 1 0 446
Cancer-(w) Carbon Tetrachloride (CC14) 16 483 833
Cancer— (a) Benzo(k)fluoranthene 12 333 565
Cancer-(w) Hexachloroethane (C2C16) 8 4 1 5 642
Cancer-(w) Phenol (C6H5OH) 8018000
Noncancer-(a) Cadmium (Cd) 4 950 421
Cancer-(a) Trichloropropane (1,2,3-C2H5C13) 3 587 000
Cancer-(a) Chromium (Cr III, Cr VI) 3 530 974
Cancer-(a) Dimethyl Sulfate (C2H6O4S) 2 976 375
Cancer-(a) Cadmium (Cd) 1 759 294
Cancer-(a) Indeno (l,2,3,c,d) Pyrene 1 730 81 1
Noncancer-(a) Lead (Pb) 1 501 293
Cancer— (a) Dibenzo(a,h)anthracene 1 419 586
Cancer— (a) Benzo(b)fluoranthene 1 356 632
Cancer— (a) Benzo(bjk)fluoranthene 1 356632
Cancer-(a) Lead (Pb) 748 3 1 6
Cancer-(a) Ethylene Oxide (C2H4O) _ 650701
smog index = Z; ni; x SP;, where
m; = mass (in grams) of inventory flow i, and
SP; = grams of nitrogen oxides with the same potential for smog formation as one gram
of inventory flow i.
There are more than 100 flows included in the BEES smog assessment. A sampling of the most
important of these flows and their characterization factors are reported in Table 2.8, sorted in
descending order of nitrogen oxides equivalents.40 To browse the entire list of smog flows and
factors, open the file EQUIV12.DBF under the File/Open menu item in the BEES software.
40 ibid.
21
-------
Table 2. 8 Sampling of BEES Smog Characterization Factors
(nitrogen oxides-
_ Flow (i) _ equivalents)
Furan(C4H4O) 3.54
Butadiene (1,3 -CH2CHCHCH2) 3.23
Propylene (CH3CH2CH3) 3.07
Xylene (m-C6H4(CH3)2) 2.73
Butene (1-CH3CH2CHCH2) 2.66
Crotonaldehyde (C4H6O) 2.49
Formaldehyde (CH2O) 2.25
Propionaldehyde (CH3CH2CHO) 2.05
Acrolein (CH2CHCHO) 1 . 99
Xylene (o-C6H4(CH3)2) 1.93
Xylene (C6H4(CH3)2) 1.92
Trimethyl Benzene (1,2,4-C6H3(CH3)3) 1.85
Acetaldehyde (CH3CHO) 1.79
Aldehyde (unspecified) 1.79
Butyraldehyde (CH3CH2CH2CHO) 1.74
Isobutyraldehyde ((CH3)2CHCHO) 1.74
Ethylene Glycol (HOCH2CH2OH) 1 .40
Acenaphthene (Ci2Hio) 1.30
Acenaphthylene (Ci2Hg) 1.30
Hexanal (C6Hi2O) 1.25
Nitrogen Oxides (NOx as NO2) 1 .24
Glycol Ether (unspecified) 1.11
Methyl Naphthalene (2-CnHio) 1.10
Xylene (p-C6H4(CH3)2) 1.09
Toluene (C6H5CH3) _ 1.03
Ozone Depletion Potential. The ozone layer is present in the stratosphere and acts as a filter
absorbing harmful short wave ultraviolet light while allowing longer wavelengths to pass
through. A thinning of the ozone layer allows more harmful short wave radiation to reach the
Earth's surface, potentially causing changes to ecosystems as flora and fauna have varying
abilities to cope with it. There may also be adverse effects on agricultural productivity. Effects
on man can include increased skin cancer rates (particularly fatal melanomas) and eye cataracts,
as well as suppression of the immune system. Another issue is the uncertain effect on the
climate.
Characterization factors for potential ozone depletion are included in the TRACT set of U.S.
impact assessment methods, with CFC-11 as the reference substance. These factors permit
computation of a single index for potential ozone depletion (in grams of CFC-11 per functional
unit of product), representing the quantity of CFC-11 with the same potential for ozone
depletion:
ozone depletion index = Z; ni; x OP;, where
22
-------
m; = mass (in g) of inventory flow i, and
OP; = grams of CFC-1 1 with the same ozone depletion potential as one gram of inventory
flow i, as listed in Table 2.9.41
Table 2. 9 BEES Ozone Depletion Potential Characterization Factors
Flow (i)
Carbon Tetrachloride (CCw)
CFC 12 (CC12F2)
Halon 1301 (CF3Br)
HCFC 22 (CHF2C1)
Methyl Bromide (CH3Br)
Trichloroethane (1,1,1-CH3CC13)
(CFC-11
equivalents)
1.10
1.00
10.00
0.06
0.60
0.10
Ecological Toxicity. The ecological toxicity impact measures the potential of a chemical released
into the environment to harm terrestrial and aquatic ecosystems. An assessment method for this
impact was developed for the TRACT set of U.S. impact assessment methods and adopted in
BEES. The method involves measuring pollutant concentrations from industrial sources as well
as the potential of these pollutants to harm ecosystems.
TRACT characterization factors for potential ecological toxicity use 2,4-dichlorophenoxy-acetic
acid (2,4-D) as the reference substance. These factors permit computation of a single index for
potential ecological toxicity (in grams of 2,4-D per functional unit of product), representing the
quantity of 2,4-D with the same potential for ecological toxicity:
ecological toxicity index = Z; ni; x EP;, where
m; = mass (in grams) of inventory flow i, and
EP; = grams of 2,4-D with the same ecological toxicity potential as one gram of inventory
flowi.
There are more than 150 flows included in the BEES ecological toxicity assessment. A sampling
of the most important of these flows and their characterization factors are reported in Table 2.10,
sorted in descending order of 2,4-D equivalents.42 Flows to air are preceded with the designation
"(a)" and flows to water with the designation "(w)." To browse the entire list of ecological
toxicity flows and factors, open the file EQUIV12.DBF under the File/Open menu item in the
BEES software.
Table 2.10 Sampling of BEES Ecological Toxicity Potential Characterization Factors
41 ibid.
42 ibid
23
-------
Flow (i) (2,4-D equivalents)
(a) Dioxins (unspecified) 2 486 822.73
(a) Mercury (Hg) 118758.09
(a) Benzo(g,h,i)perylene (C22Hi2) 4948.81
(a) Cadmium (Cd) 689.74
(a) Benzo(a)anthracene 412.83
(a) Chromium (Cr VI) 203.67
(w) Naphthalene (Ci0H8) 179.80
(a) Vanadium (V) 130.37
(a) Benzo(a)pyrene (C20Hi2) 109.99
(a) Beryllium (Be) 106.56
(a) Arsenic (As) 101.32
(a) Copper (Cu) 89.46
(w) Vanadium (V3+, V5+) 81.82
(a) Nickel (Ni) 64.34
(w) Mercury (Hg+, Hg++) 58.82
(a) Cobalt (Co) 49.45
(a) Selenium (Se) 35.07
(a) Fluoranthene 29.47
(w) Copper (Cu+, Cu++) 26.93
(a) Chromium (Cr III, Cr VI) 24.54
(w) Cadmium (Cd++) 22.79
(w) Formaldehyde (CH2O) 22.62
(a)Zinc(Zn) 18.89
(w) Beryllium (Be) 16.55
(a) Lead (Pb) 12.32
2.1.3.3 Normalizing Impacts in BEES
Once impacts have been characterized, the resulting impact category performance measures are
expressed in noncommensurate units. Global warming is expressed in carbon dioxide
equivalents, acidification in hydrogen ion equivalents, eutrophication in nitrogen equivalents,
and so on. In order to assist in the next LCA step, interpretation, performance measures are often
placed on the same scale through normalization.
The U.S. EPA Office of Research and Development has developed normalization data
corresponding to its TRACI set of impact assessment methods.43 These data are used in BEES to
43J.C. Bare et al, "U.S. Normalization Database and Methodology for Use within Life Cycle Impact
Assessment," submitted to the Journal of Industrial Ecology. Note that while a normalization value is not reported
for the Indoor Air Quality impact, a figure for U.S. VOC emissions/year/capita is reported. To approximate the
Indoor Air Quality normalization value, 30% of this reported value is taken, based on a U.S. EPA Fact Sheet citing
that 30% of annual U.S. VOC emissions flow from consumer products such as surface coatings, personal care
products, and household cleaning products (U.S. Environmental Protection Agency, Fact Sheet: Final Air
Regulations for Consumer Products, 1998). Further note that an error in the original U.S. EPA-reported Human
Health normalization value was corrected in 2007 by Greg Norris of Sylvatica, Inc., under contract to NIST, and
incorporated in BEES 4.0.
24
-------
place its impact assessment results on the same scale. The data, reported in Table 2.11, estimate
for each impact its performance at the U.S. level. Specifically, inventory flows contributing to
each impact have been quantified and characterized in terms of U.S. flows per year per capita.44
Summing all characterized flows for each impact then yields, in effect, impact category
performance measures for the United States. As such, they represent a "U.S. impact yardstick"
against which to evaluate the significance of product-specific impacts. Normalization is
accomplished by dividing BEES product-specific impact values by the fixed U.S.-scale impact
values, yielding an impact category performance measure that has been placed in the context of
all U.S. activity contributing to that impact. By placing each product-specific impact measure in
the context of its associated U.S. impact measure, the measures are all reduced to the same scale,
allowing comparison across impacts.
Table 2.11 BEES Normalization Values
Impact
Normalization Value
Global Warming
Acidification
Eutrophication
Fossil Fuel Depletion
Indoor Air Quality
Habitat Alteration
Water Intake
Criteria Air Pollutants
Smog
Ecological Toxicity
Ozone Depletion
Human Health
25 582 640.09 g CO2 equivalents/year/capita
7 800 200 000.00 millimoles H+ equivalents/year/capita
19 214.20 g N equivalents/year/capita
35 309.00 MJ surplus energy/year/capita
35 108.09 g TVOCs/year/capita
0.00335 T&E count/acre/capita21
529 957.75 liters of water/year/capita
19 200.00 microDALYs/year/capita
151 500.03 gNOx equivalents/year/capita
81 646.72 g 2,4-D equivalents/year/capita
340.19 g CFC-11 equivalents/year/capita
274 557 555.37 g C?H8 equivalents/year/capita
aOne acre is equivalent to 0.40 hectares.
Normalized BEES impact scores have powerful implications. First, by evaluating a product's
impacts with reference to their importance in a larger context, an impact to which a product
contributes little will not appear important when, by comparison, competing products contribute
even less to that impact.
Second, while selecting among building products continues to make sense only within the same
building element, like floor covering, normalized impact scores can now be compared across
building elements if they are first scaled to reflect the product quantities to be used in the
building under analysis. Take the example of global warming scores for roof coverings and
chairs. If these scores are each first multiplied by the quantity of their functional units to be used
in a particular building (roof area to be covered and seating requirements, respectively), they
may then be compared. Comparing across elements can provide insights into which building
elements lead to the larger environmental impacts, and thus warrant the most attention.
Habitat alteration flows have been quantified and characterized in terms of U.S. flows per 0.40 hectares (per
acre) per capita.
25
-------
2.1.4 Interpretation
At the LCA interpretation step, the normalized impact assessment results are evaluated. Few
products are likely to dominate competing products in all BEES impact categories. Rather, one
product may out-perform the competition relative to fossil fuel depletion and habitat alteration,
fall short relative to global warming and acidification, and fall somewhere in the middle relative
to indoor air quality and eutrophication. To compare the overall environmental performance of
competing products, the performance scores for all impact categories may be synthesized. Note
that in BEES, synthesis of impact scores is optional.
Impact scores may be synthesized by weighting each impact category by its relative importance
to overall environmental performance, then computing the weighted average impact score. In the
BEES software, the set of importance weights is selected by the user. Several alternative weight
sets are provided as guidance, and may be either used directly or as a starting point for
developing user-defined weights. The alternative weights sets are based on an EPA Science
Advisory Board study, a 2006 BEES Stakeholder Panel's structured judgments, and a set of
equal weights, representing a spectrum of ways in which people value diverse aspects of the
environment.
Refer to Appendix A for the BEES environmental performance computational algorithms and to
Appendix B for a primer on interpreting BEES environmental performance scores.
2.1.4.1 EPA Science Advisory Board study
In 1990 and again in 2000, EPA's Science Advisory Board (SAB) developed lists of the relative
importance of various environmental impacts to help EPA best allocate its resources.45 The
following criteria were used to develop the lists:
• The spatial scale of the impact
• The severity of the hazard
• The degree of exposure
• The penalty for being wrong
Ten of the twelve BEES impact categories were included in the SAB lists of relative importance:
• Highest-Risk Problems: global warming, habitat alteration
• High-Risk Problems: indoor air quality, ecological toxicity, human health
• Medium-Risk Problems: ozone depletion, smog, acidification, eutrophication, criteria air
pollutants
The SAB did not explicitly consider fossil fuel depletion or water intake as impacts. For this
exercise, fossil fuel depletion and water intake are assumed to be relatively medium-risk and
low-risk problems, respectively, based on other relative importance lists.46
45 United States Environmental Protection Agency, Science Advisory Board, Toward Integrated Environmental
Decision-Making, EPA-SAB-EC-00-011, Washington, D.C., August 2000 and United States Environmental
Protection Agency, Science Advisory Board, Reducing Risk: Setting Priorities and Strategies for Environmental
Protection, SAB-EC-90-021, Washington, D.C., September 1990, pp. 13-14.
26
-------
Verbal importance rankings, such as "highest risk," may be translated into numerical importance
weights by following ASTM standard guidance provided by a Multi attribute Decision Analysis
method known as the Analytic Hierarchy Process (AHP).47 The AHP methodology suggests the
following numerical comparison scale:
1 Two impacts contribute equally to the objective (in this case environmental performance)
3 Experience and judgment slightly favor one impact over another
5 Experience and judgment strongly favor one impact over another
7 One impact is favored very strongly over another, its dominance demonstrated in practice
9 The evidence favoring one impact over another is of the highest possible order of
affirmation
2,4,6,8 When compromise between values of 1, 3, 5, 7, and 9, is needed.
Through an AHP process known as pairwise comparison, numerical comparison values are
assigned to each possible pair of environmental impacts. Relative importance weights can then
be derived by computing the normalized eigenvector of the largest eigenvalue of the matrix of
pairwise comparison values. Tables 2.12 and 2.13 list the pairwise comparison values assigned
to the verbal importance rankings, and the resulting SAB importance weights computed for the
BEES impacts, respectively. Note that the pairwise comparison values were assigned through an
iterative process based on NIST's background and experience in applying the AHP technique.
Table 2.12 ^«^£^£^»Ef£E£2_^^^^£^££!Z!ffiJ2Ef£L^^£2J2Ef£^2£e Weights
_jP£T^^
Highest vs. Low 6
Highest vs. Medium 3
Highest vs. High 1.5
High vs. Low 4
High vs. Medium 2
Medium vs. Low 2
46 See, for example, Hal Levin, "Best Sustainable Indoor Air Quality Practices in Commercial Buildings," Third
International Green Building Conference and Exposition—1996, NIST Special Publication 908, Gaithersburg, MD,
November 1996, p. 148.
47 ASTM International, Standard Practice for Applying the Analytic Hierarchy Process to Multiattribute
Decision Analysis of Investments Related to Buildings and Building Systems, ASTM Designation E1765-02, West
Conshohocken, PA, 2002; and Thomas L. Saaty, MultiCriteria Decision Making: The Analytic Hierarchy Process-
Planning, Priority Setting, Resource Allocation, University of Pittsburgh, 1988.
27
-------
Table 2.13 Relative Importance Weights based on Science Advisory Board Study
Relative
Importance
Weight (%)
Impact Category
Global Wanning 16
Acidification 5
Eutrophi cation 5
Fossil Fuel Depletion 5
Indoor Air Quality 11
Habitat Alteration 16
Water Intake 3
Criteria Air Pollutants 6
Smog 6
Ecological Toxicity 11
Ozone Depletion 5
Human Health 11
2.1.4.2 BEES Stakeholder Panel judgments
With version 4.0, BEES introduces a new optional weight set. While the derived, EPA SAB-
based weight set is valuable and offers expert guidance,48 several interpretations and assumptions
were required in order to translate SAB findings into numerical weights for interpreting LCA-
based analyses. A more direct approach to weight development would consider a closer match
to the context of the application; that is, environmentally preferable purchasing in the United
States based on life-cycle impact assessment results, as reported by the BEES software.
In order to develop such a weight set, NIST assembled a volunteer stakeholder panel that met at
its facilities in Gaithersburg, Maryland, for a full day in May 2006. To convene the panel,
invitations were sent to individuals representing one of three "voting interests:" producers (e.g.,
building product manufacturers), users (e.g., green building designers), and LCA experts.
Nineteen individuals participated in the panel: seven producers, seven users, and five LCA
experts. These "voting interests" were adapted from the groupings ASTM International employs
for developing voluntary standards, in order to promote balance and support a consensus
process.
The BEES Stakeholder Panel was led by Dr. Ernest Forman, founder of the premier AHP firm
Expert Choice Inc. Dr. Forman facilitated panelists in weighting the BEES impact categories
using the AHP pairwise comparison process. The panel weighted all impacts in the Short Term
(0 years to 10 years), Medium Term (10 years to 100 years), and Long Term (>100 years). One
year's worth of U.S. flows for each pair of impacts was compared, with respect to their
contributions to environmental performance. For example, for an impact comparison over the
48 The 1992 Harvard University study-based weight set included in prior BEES versions has been abandoned
because its data are out of date.
28
-------
Long Term, the panel was evaluating the effect that this year's U.S. emissions would have more
than 100 years hence.
Once the panel pairwise compared impacts for the three time horizons, its judgments were
synthesized across these time horizons. Note that when synthesizing judgments across voting
interests and time horizons, all panelists were assigned equal importance, while the short,
medium, and long-term time horizons were assigned by the panel to carry 24 %, 31 %, and 45 %
of the weight, respectively.
Prior versions of BEES combined TRACI-based measures of cancerous and noncancerous health
effects into a single Human Health impact because deriving the EPA SAB weight set was only
possible at the combined level. For the BEES Stakeholder Panel event, however, Cancerous and
Noncancerous effects were judged separately to enable a more refined assessment of these two
constituents of the Human Health impact. If the BEES 4.0 user chooses to interpret life-cycle
impact assessment results using the BEES Stakeholder Panel weight set, then, impact-based
results may be viewed separately for cancerous and noncancerous health effects. For
compatibility with the other BEES 4.0 weighting schemes, however, these results are weighted
and combined into a single Human Health impact for display of BEES Environmental
Performance Scores.
The environmental impact importance weights developed through application of the AHP
technique at the facilitated BEES Stakeholder Panel event are shown in Table 2.14. These
weights reflect a synthesis of panelists' perspectives across all combinations of stakeholder
voting interest and time horizon. The weight set draws on each panelist's personal and
professional understanding of, and value attributed to, each impact category. While the
synthesized weight set may not equally satisfy each panelist's view of impact importance, it does
reflect contemporary values in applying LCA to real world decisions. This synthesized BEES
Stakeholder Panel weight set is offered as an option in the BEES software.
29
-------
Table 2.14 Relative Int£ortanc£jVeights_b^ed_ori^EES_Stakeholder Panel Judgments
Relative
Impact Category Importance
Global Wanning 29
Acidification 3
Eutrophi cation 6
Fossil Fuel Depletion 10
Indoor Air Quality 3
Habitat Alteration 6
Water Intake 8
Criteria Air Pollutants 9
Smog 4
Ecological Toxicity 7
Ozone Depletion 2
Cancerous
Human Effects
Health Noncancerous
_ Effects
The three figures below display in graphical form the BEES Stakeholder Panel weights. Figure
2.3 displays the synthesized weight set, Figure 2.4 the weights specific to panelist voting
interest, and Figure 2.5 the weights specific to time horizon. The BEES user is free to interpret
results using any of the weight sets displayed in Figures 2.4 and 2.5 by entering them as a user-
defined weight set in the BEES software.
30
-------
35%
30%
25%
20%
15%
10%
5%
0%
Impact Category
Figure 2.3 BEES Stakeholder Panel Importance Weights Synthesized across Voting Interest
and Time Horizon
31
-------
oco/
•\ c ^
c/ ^v°v^
• Producers
a Users
LCA Experts
-i
_TI B-^ • •_ J~l r-^
- r- k-i— . -.
ru nr, >, i h i [Tl 11
/V' ^°X^ ^^/^
Figure 2.4 BEES Stakeholder Panel Importance Weights by Stakeholder Voting Interest
cfW
400/
oco/
oco/
•ICO/
•i n"/
CO/
r\o/ 1 1 n M~l
C Short (<10 years)
D Medium (10 years to 100 years)
D Long (>1 00 years)
n
1
• n nnrtarbrTTrhTIrl l~Lr
T^ zlKntn trln n n r tr m
Figure 2.5 BEES Stakeholder Panel Importance Weights by Time Horizon
32
-------
2.2 Economic Performance
Measuring the economic performance of building products is more straightforward than
measuring environmental performance. Published economic performance data are readily
available, and there are well-established ASTM standard methods for conducting economic
performance evaluations. First cost data are collected from the R.S. Means publication, 2007
Building Construction Cost Data, and industry interviews, while future cost data are based on
data published by Whitestone Research in The Whitestone Building Maintenance and Repair
Cost Reference 2006-2007 and industry interviews. The most appropriate method for measuring
the economic performance of building products is the life-cycle cost (LCC) method. BEES
follows the ASTM standard method for life-cycle costing of building-related investments.49
It is important to distinguish between the time periods used to measure environmental
performance and economic performance. These time periods are different. Recall that in
environmental LCA, the time period begins with raw material acquisition and ends with product
end-of-life. Economic performance, on the other hand, is evaluated over a fixed period (known
as the study period) that begins with the purchase and installation of the product and ends at
some point in the future that does not necessarily correspond with product end-of-life.
Economic performance is evaluated beginning at product purchase and installation because this
is when out-of-pocket costs begin to be incurred, and investment decisions are made based upon
out-of-pocket costs. The study period ends at a fixed date in the future. For a private investor, its
length is set at the period of product or facility ownership. For society as a whole, the study
period length is often set at the useful life of the longest-lived product alternative. However,
when alternatives have very long lives, (e.g., more than 50 years), a shorter study period may be
selected for three reasons:
• Technological obsolescence becomes an issue
• Data become too uncertain
• The farther in the future, the less important the costs
In the BEES model, economic performance is measured over a 50-year study period, as shown in
Figure 2.6. This study period is selected to reflect a reasonable period of time over which to
evaluate economic performance for society as a whole. The same 50-year period is used to
evaluate all products, even if they have different useful lives. This is one of the strengths of the
LCC method. It accounts for the fact that different products have different useful lives by
evaluating them over the same study period.
For consistency, the BEES model evaluates the use stage of environmental performance over the
same 50-year study period. Product replacements over this 50-year period are accounted for in
49E917-05 Standard Practice for Measuring Life-Cycle Costs of Buildings and Building Systems ASTM
International, Standard Practice for Measuring Life-Cycle Costs of Buildings and Building Systems, ASTM
Designation E917-05, West Conshohocken, PA, 2005.
33
-------
the life cycle inventory analysis, and end-of-life inventory flows are prorated to year 50 for
products with lives longer than the 50-year study period.
The LCC method sums over the study period all relevant costs associated with a product.
Alternative products for the same function, say floor covering, can then be compared on the basis
of their LCCs to determine which is the least cost means of fulfilling that function over the study
period. Categories of cost typically include costs for purchase, installation, operation,
maintenance, repair, and replacement. A negative cost item is the residual value. The residual
value is the product value remaining at the end of the study period. In the BEES model, the
residual value is computed by prorating the purchase and installation cost over the product life
remaining beyond the 50-year period.50
Site Selection
and
Preparation
F
:ACILITYLIFE CYCLE
Construction
and Outfitting
i
k
Product
Manufacture
i
k
Raw
Materials
Acquisition
E
^
ECONOMIC STUDY PERIOD
Operation Renovation
and Use or Demolition
ENVIRONMENTAL
STUDY PERIOD
Figure 2.6 BEES Study Periods For Measuring Building Product Environmental And
Economic Performance
The LCC method accounts for the time value of money by using a discount rate to convert all
future costs to their equivalent present value. Refer to Appendix A for the BEES economic
performance computational algorithm showing the discounting technique.
Future costs must be expressed in terms consistent with the discount rate used. There are two
approaches. First, a real discount rate may be used with constant-dollar (e.g., 2006) costs. Real
discount rates reflect that portion of the time value of money attributable to the real earning
power of money over time and not to general price inflation. Even if all future costs are
expressed in constant 2006 dollars, they must be discounted to reflect this portion of the time-
value of money. Second, a market discount rate may be used with current-dollar amounts (e.g.,
50 For example, a product with a 40 year life that costs $111/m2 ($10/ft2) to install would have a residual value of
$7.50 in year 50, considering replacement in year 40.
34
-------
actual future prices). Market discount rates reflect the time value of money stemming from both
inflation and the real earning power of money over time. When applied properly, both
approaches yield the same LCC results. The BEES model computes LCCs using constant 2006
dollars and a real discount rate.51 As a default, the BEES tool offers a real rate of 3.0 %, the 2006
rate mandated by the U.S. Office of Management and Budget for most Federal projects.52
2.3 Overall Performance
The BEES overall performance measure synthesizes the environmental and economic results into
a single score, as illustrated in Figure 2.7. Yet the environmental and economic performance
scores are denominated in different units. How can these diverse measures of performance be
combined into a meaningful measure of overall performance? The most appropriate technique is
Multiattribute Decision Analysis (MADA). MADA problems are characterized by tradeoffs
between apples and oranges, as is the case with the BEES environmental and economic
performance results. The BEES system follows the ASTM standard for conducting MADA
evaluations of building-related investments.53
Before combining the environmental and economic performance scores, each is placed on a
common scale by dividing by the sum of corresponding scores across all alternatives under
analysis. In effect, then, each performance score is rescaled in terms of its share of all scores, and
is placed on the same, relative scale from 0 to 100. Then the two scores are combined into an
overall score by weighting environmental and economic performance by their relative
importance and taking a weighted average. The BEES user specifies the relative importance
weights used to combine environmental and economic performance scores and should test the
sensitivity of the overall scores to different sets of relative importance weights. Refer to
Appendix A for the BEES overall performance computational algorithm.
2.4 Limitations
Properly interpreting the BEES scores requires placing them in perspective. There are inherent
limits to applying U.S. average LCA and LCC results and in comparing building products
outside the design context.
The BEES LCA and LCC approaches produce U.S. average performance results for generic and
manufacturer-specific product alternatives. The BEES results do not apply to products sold in
other countries where manufacturing and agricultural practices, fuel mixes, environmental
51 Any year 2002 costs were converted to year 2006 dollars using a 1.126 inflation factor developed from
consumer price indices for housing reported in U.S. Department of Labor, Consumer Price Index: All Urban
Consumers, Series CUUROOOOSAH, Bureau of Labor Statistics, http://data.bls.gov, January 3, 2007.
52 U.S. Office of Management and Budget (OMB) Circular A-94, Guidelines and Discount Rates for Benefit-
Cost Analysis of Federal Programs, Washington, DC, October 27, 1992 and OMB Circular A-94, Appendix C,
Washington, DC, January 2007.
53 ASTM International, Standard Practice for Applying the Analytic Hierarchy Process to Multiattribute
Decision Analysis of Investments Related to Buildings and Building Systems, ASTM Designation E1765-02, West
Conshohocken, PA, 2002.
35
-------
Carbon Dioxide
Methane!
Nitrous Oxide |
Global Warming
Acidification
Eutrophication
Fossil Fuel Depletion
Indoor Air Quality
Habitat Alteration
] Water Intake
Criteria Air Pollutants
Human Health
Smog
Ozone Depletion
Ecological Toxicity
First Cost
Future Costs
Environmental I
Performance
Score
Economic
Performance
Score
Overall
Score
Figure 2.7 Deriving the BEES Overall Performance Score
36
-------
regulations, transportation distances, and labor and material markets may differ.54 Furthermore,
all products in a generic product group, such as vinyl composition tile floor covering, are not
created equal. Product composition, manufacturing methods, fuel mixes, transportation
practices, useful lives, and cost can all vary for individual products in a generic product group.
The BEES results for the generic product group do not necessarily represent the performance of
an individual product.
The BEES LCAs use selected inventory flows converted to selected local, regional, and global
environmental impacts to assess environmental performance. Those inventory flows which
currently do not have scientifically proven or quantifiable impacts on the environment are
excluded, such as mineral extraction and wood harvesting which are qualitatively thought to lead
to loss of habitat and an accompanying loss of biodiversity. If the BEES user has important
knowledge about these issues, it should be brought into the interpretation of the BEES results.
Life cycle impact assessment is a rapidly evolving science. Assessment methods unheard of
several years ago have since been developed and are now being used routinely in LCAs. While
BEES 4.0 incorporates state-of-the-art impact assessment methods, the science will continue to
evolve and methods in use today—particularly those for habitat alteration, water intake, and
indoor air quality—are likely to change and improve over time. Future versions of BEES will
incorporate these improved methods as they become available.
During the interpretation step of the BEES LCAs, environmental impacts are optionally
combined into a single environmental performance score using relative importance weights.
These weights necessarily incorporate values and subjectivity. BEES users should routinely test
the effects on the environmental performance scores of changes in the set of importance weights.
The BEES LCAs do not incorporate uncertainty analysis as required by ISO 14040.55 At
present, incorporating uncertainty analysis is problematic due to a lack of underlying uncertainty
data. The BEES 2.0 Peer Review Team discussed this issue and advised NIST not to incorporate
uncertainty analysis into BEES in the short run.56 In the long run, however, one aspect of
uncertainty may be addressed: the representativeness of generic products. That is, once BEES is
extensively populated with manufacturer-specific data, the variation in manufacturer-specific
products around their generic representations will become available.
The BEES overall performance scores do not represent absolute performance. Rather, they
represent proportional differences in performance, or relative performance, among competing
alternatives. Consequently, the overall performance score for a given product alternative can
change if one or more competing alternatives are added to or removed from the set of
alternatives under consideration. In rare instances, rank reversal, or a reordering of scores, is
54 BEES does apply to products manufactured in other countries and sold in the United States. These results,
however, do not apply to those same products as sold in other countries because transport to the United States is
built into their BEES life cycle inventory data.
55 International Organization for Standardization (ISO), Environmental Management - Life-Cycle Assessment -
Principles and Framework, International Standard 14040, 2006.
56 Curran, M. A. et al., BEES 2.0, Building for Environmental and Economic Sustainability: Peer Review Report,
NISTIR 6865, National Institute of Standards and Technology, Washington, DC, 2002.
37
-------
possible. Finally, since they are relative performance scores, no conclusions may be drawn by
comparing overall scores across building elements. For example, if exterior wall finish Product
A has an overall performance score of 30, and roof covering Product D has an overall
performance score of 20, Product D does not necessarily perform better than Product A (keeping
in mind that lower performance scores are better). This limitation does not apply to comparing
environmental performance scores across building elements, as discussed in section 2.1.3.3.
There are inherent limits to comparing product alternatives without reference to the whole
building design context. Such comparisons may overlook important environmental and cost
interactions among building elements. For example, the useful life of one building element (e.g.,
floor coverings), which influences both its environmental and economic performance scores,
may depend on the selection of related building elements (e.g., subflooring). There is no
substitute for good building design.
Environmental and economic performance are but two attributes of building product
performance. The BEES model assumes that competing product alternatives all meet minimum
technical performance requirements.57 However, there may be significant differences in
technical performance, such as acoustic or fire performance, which may outweigh environmental
and economic considerations.
57 BEES environmental and economic performance results for wall insulation, roof coverings, and exterior wall
finishes do consider one important technical performance difference. For these building elements, BEES accounts
for differential heating and cooling energy consumption.
38
-------
3. BEES Product Data
The BEES model uses the ASTM standard classification system, UNIFORMAT II,58 to organize
comparable building products into groups. The ASTM standard classifies building components
into a four-level hierarchy: major group elements (e.g., substructure, shell, interiors), group
elements (e.g., foundations, roofing, interior finishes), individual elements (e.g., slab on grade,
roof coverings, floor finishes), and suggested sub-elements. Elements are defined such that each
performs a given function, regardless of design specifications or materials used. The
UNIFORMAT II classification system is well suited to the BEES environmental and economic
performance methodologies, which define comparable products as those that fulfill the same
basic function. The BEES model uses the UNIFORMAT II classification of individual elements,
the third level of the hierarchy, as the point of departure for selecting functional applications for
BEES product comparisons.
3.1 Concrete Slabs, Walls, Beams, and Columns
3.1.1 Generic Portland Cement Products
Portland cement concrete, typically referred to as "concrete," is a mixture of portland cement (a
fine powder), water, fine aggregate such as sand or finely crushed rock, and coarse aggregate
such as gravel or crushed rock. Ground granulated blast furnace slag (slag cement), fly ash, silica
fume, or limestone may be substituted for a portion of the portland cement in the concrete mix.
Concrete mixes modeled in the BEES software include compressive strengths of 21 MPa,
28 MPa, and 34 MPa (3 000 Ib/in2, 4 000 Ib/in2, and 5 000 Ib/in2). Concrete with 21 MPa
strength is used in applications such as residential slabs and basement walls, while strengths of
28 MPa and 34 MPa are used in structural applications such as beams and columns.
Portland cement concrete products like beams and columns are modeled based on volume of
concrete (e.g., a functional unit of 1 ft3), while basement walls and slabs are modeled on an area
basis (e.g., a functional unit of 1 ft2). The amount of concrete required depends on the
dimensions of the product (e.g., thickness of slab or wall and surface area). Above-grade walls
are typically 15 cm (6 in) thick. Basement walls are 20 cm (8 in) thick, slabs 10 cm (4 in) thick,
and a typical column size is 51 cm by 51 cm (20 in by 20 in).
Manufacturing data for concrete products are taken from the Portland Cement Association's
LCA database, with extensive documentation provided by the Portland Cement Association for
incorporating their LCA data into BEES.
The detailed environmental performance data for generic portland cement products may be
viewed by opening the following files under the File/Open menu item in the BEES software:
58 ASTM International, Standard Classification for Building Elements and Related Sitework—UNIFORMAT II,
ASTM Designation E1557-05, West Conshohocken, PA, 2005.
39
-------
• A1030A.DBF—100 % Portland Cement for Slabs
• A1030B.DBF—15 % Fly Ash Cement for Slabs
• A1030C.DBF—20 % Fly Ash Cement for Slabs
• A1030D.DBF—20 % Slag Cement for Slabs
• A1030E.DBF—35 % Slag Cement for Slabs
• A1030F.DBF—50 % Slag Cement for Slabs
• A1030G.DBF—5 % Limestone Cement for Slabs
• A1030H.DBF—10 % Limestone Cement for Slabs
• A1030I.DBF—20 % Limestone Cement for Slabs
• A1030O.DBF—35 % Fly Ash Cement for Slabs
• A2020A.DBF—100 % Portland Cement for Basement Walls
• A2020B.DBF—15 % Fly Ash Cement for Basement Walls
• A2020C.DBF—20 % Fly Ash Cement for Basement Walls
• A2020D.DBF—20 % Slag Cement for Basement Walls
• A2020E.DBF—35 % Slag Cement for Basement Walls
• A2020F.DBF—50 % Slag Cement for Basement Walls
• A2020G.DBF—5 % Limestone Cement for Basement Walls
• A2020H.DBF—10 % Limestone Cement for Basement Walls
• A2020I.DBF—20 % Limestone Cement for Basement Walls
• B1011 A.DBF—100 % Portland Cement 4KSI for Beams
• B101 IB.DBF—15 % Fly Ash Cement 4KSI for Beams
• B1011C.DBF—20 % Fly Ash Cement 4KSI for Beams
40
-------
• B1011D.DBF—20 % Slag Cement 4KSI for Beams
• B1011E.DBF—35 % Slag Cement 4KSI for Beams
• B1011F.DBF—50 % Slag Cement 4KSI for Beams
• B1011 G.DBF—5 % Limestone Cement 4KSI for Beams
• B1011H.DBF—10 % Limestone Cement 4KSI for Beams
• B1011I.DBF—20 % Limestone Cement 4KSI for Beams
• B1011 J.DBF—100 % Portland Cement 5KSI for Beams
• B1011K.DBF—15 % Fly Ash Cement 5KSI for Beams
• B1011L.DBF—20 % Fly Ash Cement 5KSI for Beams
• B1011M.DBF—20 % Slag Cement 5KSI for Beams
• B1011N.DBF—3 5 % Slag Cement 5KSI for Beams
• B1011O.DBF—50 % Slag Cement 5KSI for Beams
• B1011P.DBF—5 % Limestone Cement 5KSI for Beams
• B1011Q.DBF—10 % Limestone Cement 5KSI for Beams
• B1011R.DBF—20 % Limestone Cement 5KSI for Beams
• B1012A.DBF—100 % Portland Cement 4KSI for Columns
• B1012B.DBF—15 % Fly Ash Cement 4KSI for Columns
• B1012C.DBF—20 % Fly Ash Cement 4KSI for Columns
• B1012D.DBF—20 % Slag Cement 4KSI for Columns
• B1012E.DBF—35 % Slag Cement 4KSI for Columns
• B1012F.DBF—50 % Slag Cement 4KSI for Columns
• B1012G.DBF—5 % Limestone Cement 4KSI for Columns
41
-------
• B1012H.DBF—10 % Limestone Cement 4KSI for Columns
• B1012I.DBF—20 % Limestone Cement 4KSI for Columns
• B10120J.DBF—100 % Portland Cement 5KSI for Columns
• B1012K.DBF—15 % Fly Ash Cement 5KSI for Columns
• B1012L.DBF—20 % Fly Ash Cement 5KSI for Columns
• B1012M.DBF—20 % Slag Cement 5KSI for Columns
• B1012N.DBF—35 % Slag Cement 5KSI for Columns
• B1012O.DBF—50 % Slag Cement 5KSI for Columns
• B1012P.DBF—5 % Limestone Cement 5KSI for Columns
• B1012Q.DBF—10 % Limestone Cement 5KSI for Columns
• B1012R.DBF—20 % Limestone Cement 5KSI for Columns
Flow Diagram
The flow diagrams below show the major elements of the production of portland cement
concrete products with and without cement substitutes such as fly ash, slag, and limestone.
42
-------
Concrete Without Cement Substitutes
Energy
Raw Material
Transport
Ready-Mix
Plant
Process
Energy
Process
Energy
Raw Material
Transport
Kiln
t
Cement Rne
t
Cement
Rock/Marl
Production
Clay
Production
Figure 3.1: Concrete without Cement Substitutes System Boundaries
43
-------
Concrete With Cement Substitutes
Functional Unit of
Portland Cement
Concrete With
Supplementary
Cementitious Materials
1
L
Fine Aggregate
Production
Figure 3.2: Concrete with Cement Substitutes System Boundaries
Raw Materials
As noted above, the constituents of portland cement concrete are portland cement (a fine
powder), water, fine aggregate such as sand or finely crushed rock, and coarse aggregate such as
gravel or crushed rock. Ground granulated blast furnace slag (slag cement), fly ash, silica fume,
or limestone may be substituted for a portion of the portland cement in the concrete mix.
Typically, fly ash and slag are equal replacements by weight for cement. The same is true for a
5 % limestone blended cement, but at the 10 % and 20 % blend levels, more blended cement is
needed in the concrete to achieve equivalent strength as mixes with no limestone replacements.
Quantities of constituent materials used in an actual project will vary. Mix designs (that is, the
44
-------
constituent quantities) and strength will also vary depending on the aggregates and cement used.
The following Table shows quantities of concrete constituents for the three compressive
strengths modeled. Other materials that are sometimes added, such as silica fume and chemical
admixtures, are not considered.
Table 3.1: Concrete Constituent Quantities by Cement Blend
yndConmresstveStrensthofConcre^
Constituent
Cement and Fly Ash, Slag, or
5 % Limestone
Coarse Aggregate
Fine Aggregate
Water
Cement and 10 % Limestone
Coarse Aggregate
Fine Aggregate
Water
Cement and 20 % Limestone
Coarse Aggregate
Fine Aggregate
Water
(
21MPa
(3 000 lb/in2)
223 (376)
1 127 (1 900)
831 (1 400)
141 (237)
236 (397)
1 127 (1 900)
831 (1 400)
148 (250)
265 (447)
1 127 (1 900)
831 (1 400)
167(281)
Constituent Density
in kg/m3(lb/y(f)
28MPa
(4 000 lb/in2)
279 (470)
1 187(2000)
771 (1 300)
141 (237)
294 (496)
1 187(2000)
771 (1 300)
147 (248)
331 (558)
1 127 (1 900)
771 (1 300)
166 (279)
7
34MPa
(5 000 lb/in2)
335 (564)
1 187(2000)
712(1200)
141 (237)
353 (595)
1 187(2000)
712(1200)
148 (250)
397 (670)
1 187(2000)
653 (1 100)
167(281)
Portland Cement Production. Cement plants are located throughout North America at locations
with adequate supplies of raw materials. Major raw materials for cement manufacture include
limestone, cement rock/marl, shale, and clay. These raw materials contain various proportions of
calcium oxide, silicon dioxide, aluminum oxide, and iron oxide, with oxide content varying
widely across North America. Since portland cement must contain the appropriate proportion of
these oxides, the mixture of the major raw materials and minor ingredients (as required) varies
among cement plants.
BEES data for cement manufacture is based on the average raw material mix and oxide content
for all U.S. cement plants for ASTM C150 Type I/II cement, the most commonly used cement in
North America. The average raw materials for U.S. cement include limestone, cement rock/marl,
shale, clay, bottom ash, fly ash, foundry sand, sand, and iron/iron ore. For the BEES model, the
raw materials listed in the Table below are used.59
59 The weight of inputs is greater than the weight of portland cement output, as a significant percentage of the
weight of limestone is released as CO2.
45
-------
Table 3.2: Portland Cement Constituents
Constituent
Limestone
Cement rock, marl
Clay
Shale
Sand
Slag
Iron/iron ore
Fly ash
Bottom ash
Foundry sand
Slate
Mass of
in£u^_w_kg_
1.17
0.21
0.06
0.05
0.04
0.02
0.01
0.01
0.01
0.004
0.001
Mass
Fraction
72.2 %
12.8 %
3.7%
3.2%
2.5 %
1.2%
0.9 %
0.8 %
0.6 %
0.2 %
0.1 %
In the manufacturing process, major raw materials are blended with minor ingredients, as
required, and processed at high temperatures in a cement kiln to form an intermediate material
known as clinker. Gypsum is interground with clinker to form portland cement. Gypsum content
is assumed to be added at 3.0 % (by mass fraction) of portland cement.
Portland cement is manufactured using one of four processes: wet, long dry, preheater, or
precalciner. The wet process is the oldest and uses the most energy due to the energy required to
evaporate the water. New cement manufacturing plants are being constructed, and older plants
converted, to use the more energy efficient preheater and precalciner processes. The mix of
production processes modeled is 16.5% wet, 14.4% dry, 15.8% preheater, and 53.3%
precalciner.60
The following Table presents U.S. industry-average energy use by process and fuel type, and, for
all processes combined, average energy use weighted by the process mix. The production of the
different types of fuel is based on the U.S. LCI Database; however, production of "wastes" used
as fuel is assumed to be free of any environmental burdens to portland cement production.
60 Portland Cement Association, U.S. and Canadian Labor-Energy Input Survey 2002 (Skokie, IL: Portland
Cement Association, 2005).
46
-------
Table 3.3: Energy Requirements for Portland Cement Manufacturing
Cement Manufacturing Process
Energy Carrier Weighted
Wet_ I^!1JL^
Coal
Petroleum Coke
Electricity
Wastes
Natural Gas
_J_Jxnaid Fuels
All Fuels
Total Energy -
kJ/kg of cement
50%
18%
8%
23%
1%
1%
100%
6400
(2 749)
50%
33%
10%
3%
4%
1%
100 %
5591
(2 402)
70%
11%
12%
2%
3%
1%
100 %
4357
(1 872)
63%
11%
12%
6%
7%
1%
100 %
4220
(1 813)
60%
15%
11 %
8%
5%
1%
100%
4798
(2061)
* Cement constitutes 10 % to 15 % by mass fraction of the total mass of concrete.
** Liquid fuels include gasoline, middle distillated, residual oil, and light petroleum gas
Emissions for portland cement manufacturing are from the Portland Cement Association cement
LCA database.61 Emissions include particulate matter, carbon dioxide (CO2), carbon monoxide
(CO), sulfur oxides (SOX), nitrogen oxides (NOX), total hydrocarbons, and hydrogen chloride
(HC1). Emissions vary for the different combinations of compressive strength and blended
cements.
The major waste material from cement manufacturing is cement kiln dust (CKD). There is no
breakdown of CKD by process type. An industry average of 38.6 kg of CKD is generated per
metric ton (93.9 Ib/ton) of cement. Of this, 30.7 kg (74.6 Ib) is landfilled and 7.9 kg (19.3 lb) is
reused on-site or enters commerce as inputs to the agricultural, construction, and waste treatment
industries.62
Aggregate Production. Aggregate is a general term that describes a filler material in concrete.
Aggregate generally provides 60 % to 75 % of the concrete volume. Typically, aggregate
consists of a mixture of coarse and fine rocks. Aggregate is either mined or manufactured. Sand
and gravel are examples of mined aggregate. These materials are dug or dredged from a pit,
river bottom, or lake bottom and require little or no processing. Crushed rock is an example of
manufactured aggregate. Crushed rock is produced by crushing and screening quarry rock,
boulders, or large-sized gravel. Approximately half of the coarse aggregate used in the United
States is crushed rock.
Concrete contains 25 % coarse and fine aggregate from crushed rock and 75 % coarse and fine
61 Nisbet, M.A., Marceau, M.L., and VanGeem, M.G. "Life Cycle Inventory of Portland Cement Manufacture"
(an appendix to Environmental Life Cycle Inventory of Portland Cement Concrete), PCA R&D Serial No. 2095a
(Skokie, IL: Portland Cement Association, 2002).
62 Bhatty, J., et al., Innovations in Portland Cement Manufacturing (Skokie, IL: Portland Cement Association,
2004).
47
-------
aggregate from sand and gravel.63 The energy to produce coarse and fine aggregate from crushed
rock is 81 kJ/kg (35 Btu/lb), and the energy to produce coarse and fine aggregate from uncrushed
aggregate is 17 kJ/kg (7.3 Btu/lb).64 The energy for aggregate production is a 50:50 mix of diesel
oil and electricity.
Fly Ash Production. Fly ash is a waste material that results from burning coal to produce
electricity. In LCA terms, fly ash is an environmental outflow of coal combustion, and an
environmental inflow of concrete production. This waste product is assumed to be an
environmentally "free" input material.65 However, transport of the fly ash to the ready mix plant
is included.
Ground Granulated Blast Furnace Slag (Slag Cement) Production. Slag cement is a waste
material that is a result of the production of steel. Similar to fly ash, slag is an environmental
outflow of steel production and an environmental inflow of concrete production. Therefore, slag
is considered to be an environmentally "free" input material. Unlike fly ash, slag must be
processed prior to inclusion in concrete. Processing consists of quenching and granulating at the
steel mill, transport to the grinding facility, and finish grinding. This production energy (an
assumed 75:25 mix of electricity and natural gas) is assumed to be 722 kJ/kg of slag cement (311
Btu/lb). Transportation to the ready mix plant is included.
Limestone Production. While not common practice in the United States, limestone is used as a
partial replacement for portland cement in most European countries. The concrete mix designs
used in BEES are estimates based on available literature and have not been tested in the
laboratory. Mixes at the higher limestone replacement levels are based on limited data. Energy
burdens for limestone production are taken from the U.S. LCI Database.
Manufacturing
Energy Requirements and Emissions. Most portland cement concrete is produced at a central
ready mix plant. Energy use in the batch plant includes electricity and fuel used for heating and
mobile equipment.66
Table_ 3. 4: Enerj*y_ Requirement^ sjor_ Ready_ Mix Concrete^
" "
Heavy Fuel Oil 124 (o9) (o5 (22)
Electricity 124 (0.09) 0.05 (22)
" 247 (0.179) 0.1 (43)
Transportation. Round-trip distances for transport of concrete raw materials to the ready -mix
plant are assumed to be 97 km (60 mi) for portland cement and fly ash, 216 km (134 mi) for slag,
and 80 km (50 mi) for aggregate and limestone. The method of transport is truck. A small
percentage of the above materials, assumed to be 10 %, may be transported more than 3 219 km
63 U.S. Geological Survey. USGS Minerals Yearbook—2003, Volume I. Metals and Minerals (Washington, DC:
Interior Dept, Geological Survey, 2003), pp 64.1-2; 71.1-3.
64 Nisbet, M., et al. "Environmental Life Cycle Inventory of Portland Cement Concrete." PCA R&D Serial No.
2737a(Skokie, IL: Portland Cement Association, 2002).
65 The environmental burdens associated with the production of waste materials are typically allocated to the
intended product(s) of the process from which the waste results.
66 Nisbet, M., et. al, "Environmental Life Cycle Inventory of Portland Cement Concrete."
48
-------
(2 000 mi). When this is the case, transport is assumed to be by rail.
Transportation
Transportation of concrete products with portland cement by heavy-duty truck to the building
site is modeled as a variable of the BEES system.
Installation
Installing each of the BEES concrete applications requires different quantities of plywood forms
and steel reinforcement as shown in the Table below.67
67 R. S. Means Co., Inc., 2007 Building Construction Cost Data (Kingston, MA: 2006), pp. 711-713.
49
-------
Building
Element
Compressive
Strength
MPa (lb/in2)
Plywood
Forms
onalumt)
Steel
Reinforcing
(Ib/fffor
slabs, Ib/yd3
Comment
Slabs 21 (3000)
Above grade
Walls' 34 (5000)
precast
concrete
1.03
0
0
1.67
For 7.62 m (25 ft) span, 4 in thick.
Assume 6 in thick. Plywood wall
forms are reused over 75 times; hence
their environmental burdens are not
taken into account.
Assume 6 in thick. The insulation
board used as formwork becomes part
of the wall; hence no forms are used.
Assume 6 in thick. Plywood wall
forms are reused over 75 times; hence
they are not taken into account.
Above grade
walls, ICF
Above grade
walls, cast-
in-place
21 (3000)
28(4000)
135
135
135
Basement
Walls
21 (3 000)
44
Columns
28 (4 000)
Columns
34 (5 000)
Beams
28 (4 000)
Notes:
Beams 34 (5 000) 54
1. Plywood forms are 12.7 mm (0.5 in) thick
Plywood production impacts are the same as
For 0.20 m (8 in) thick, 2.44 m (8 ft)
high walls. Plywood wall forms are
reused over 75 times; hence they are
not taken into account.
For 0.51 m x 0.51 m (20 in x 20 in)
columns with a 7.62 m (25 ft) span.
Approximately 65 ft2 of plywood is
required per cubic yard of concrete.
Plywood forms are reused four times,
65 290 each time with 10 % installation
waste.
Steel reinforcements are added to the
concrete forms at 290 Ib of steel per
cubic yard of concrete. The steel
value is twice the amount for beams.
Values for forms and reinforcement
provided for 28 MPa (4 000 lb/in2)
columns are used for 34 MPa
(5 000 lb/in2) columns.
For 7.62 m (25 ft) span beams. Steel
reinforcements are added to the
concrete forms at 145 Ib of steel per
cubic yard of concrete (half of the
amount required for columns).
145 Plywood forms are reused four times,
each time with 10 % installation
waste.
Values for forms and reinforcement
provided for 28 MPa (4 000 lb/in2)
beams are used for
145 34 MPa (5 000 lb/in2) beams.
65
290
54
and their surface density is 5.88 kg/m2 (1.17 lb/ft2).
those reported for the BEES Plywood Wall Sheathing
50
-------
product.
2. SFCA=0.09 m2 (1 ft2) contact area.
3. Steel reinforcing is made from 100 % recycled steel.
The industry average for steel reinforcement is 5 Ib of steel reinforcement/ft3 of concrete (135 Ib
steel/yd3 concrete). Installation materials are assumed to be transported by truck 161 km (100
mi) to the point of installation.
Use
With general maintenance, quality concrete in buildings will generally last more than 100 years.
This is a performance-based lifetime.
Interior concrete not exposed to weather (such as beams, columns, foundations, and footings)
generally does not require maintenance. For exterior concrete, maintenance will vary depending
on weather conditions, but usually consists of minimal repairs that can be done by hand.
Maintenance is not included within the system boundaries of the BEES model.
End of Life
The majority of concrete in the U.S. is used in urban areas where concrete is not accepted at
landfills. Concrete is recycled as fill and road base, and steel used in concrete reinforcement is
recycled. Plywood forms are assumed to be disposed of in a landfill at end of life.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0LCA Software. 2005. The Netherlands.
Kosmatka, S.H., Kerkhoff, B., and Panarese W.C., Design and Control of Concrete Mixtures,
14th Ed., (Skokie, IL: Portland Cement Association, 2002). p. 327
Portland Cement Association, U.S. and Canadian Labor-Energy Input Survey 2002, (Skokie,
IL: Portland Cement Association, 2005).
Construction Technology Laboratories, Inc, "Completed BEES Site Questionnaire for Portland
Cement," CTL Project No. 312006, (Skokie, IL: Construction Technology Laboratories, Inc,
June 2002).
Construction Technology Laboratories, Inc, "Theoretical Concrete Mix Designs for Cement
with Limestone as a Partial Replacement for Portland Cement," CTL Project 312006,
(Skokie, IL: Construction Technology Laboratories, Inc, June 2002).
Construction Technology Laboratories, Inc. and JAN Consultants, "Data Transmittal for
Incorporation of Slag Containing Concrete Mixes into Version 2.0 of the BEES Software,"
PCA R&D Serial No. 2168alPCA Project 94-04, (Skokie, IL: Portland Cement Association,
2000).
Nisbet, M., et al. "Concrete Products Life Cycle Inventory (LCI) Data Set for Incorporation
into the NIST BEES Model." PCA R&D Serial No. 2168/PCA Project 94-04a, (Skokie, IL:
Portland Cement Association, 1998).
Nisbet, M.A., Marceau, M.L., and VanGeem, M.G. "Life Cycle Inventory of Portland Cement
Manufacture (an Appendix to Environmental Life Cycle Inventory of Portland Cement
51
-------
Concrete)," PCA R&D Serial No. 2095a (Skokie, IL: Portland Cement Association, 2002).
Bhatty, J., et al. Innovations in Portland Cement Manufacturing, (Skokie, IL: Portland Cement
Association, 2004).
U.S. Geological Survey. USGSMinerals Yearbook—2003, Volume I. Metals and Minerals
(Washington, DC: Interior Dept, Geological Survey, 2003). pp 64.1-2; 71.1-3. Found at:
http://minerals.usgs.gov/minerals/pubs/commodity/myb/index.html
Nisbet, M., et al. "Environmental Life Cycle Inventory of Portland Cement Concrete." PCA
R&D Serial No. 2137a, (Skokie, IL: Portland Cement Association, 2002).
R. S. Means Co., Inc., 2007 Building Construction Cost Data (Kingston, MA: 2006), pp. 711-
713.
Industry Contacts
Martha VanGeem, P.E., Construction Technology Laboratories, Inc. (on behalf of the Portland
Cement Association), August-October 2005
Medgar Marceau, P.E., Construction Technology Laboratories, Inc. (on behalf of the Portland
Cement Association), August-October 2005
3.1.2 Lafarge North America Products
Lafarge North America, part of the Lafarge Group, is a large, diversified supplier of cement,
aggregates and concrete as well as other materials for residential, commercial, institutional, and
public works construction in the United States and Canada. Four Lafarge products are included
in BEES:
• Silica Fume Cement (SFC). A mixture of portland cement (90 %) and silica fume (10 %).
• NewCem Slag Cement. Ground granulated blast furnace slag used as a partial replacement
for portland cement.
• BlockSet. A blend of cement kiln dust, fly ash, and cement used to make concrete blocks for
basement walls.
• Portland Type I Cement.
BEES data for SFC and BlockSet products come from the Lafarge plant in Paulding, Ohio, with
an annual production of 436 810 metric tons (481 500 short tons) of SFC, Type I cement, and
masonry cement.68 The Lafarge South Chicago location manufactures a total of 816 466 metric
tons (900 000 short tons) of slag products. Data for the Portland Type I Cement product come
from the Lafarge plant in Alpena, Michigan, with an annual production of 2 059 310 metric tons
(2 270 000 short tons). The portland cement manufactured in Alpena is shipped by lake vessels
to terminals around the Great Lakes. These cementitious products are incorporated in different
concrete products in BEES as shown in the Table below.
68 Annual production data is based largely on 2001 production. Other Lafarge plant data ranges in time from the
late 1990s to 2001.
52
-------
BEES Building
Element
Lafarge
Product
Specifications
Concrete for Slabs,
Basement Walls,
Beams and Columns
Silica Fume
Cement (SFC)
Slag Cement
Concrete for
Basement Walls
Parking Lot Paving
Alpena Portland
Type I
BlockSet
Alpena Portland
Type I
1 kg (2.2 Ib) of SFC is equivalent to
1 kg (2.2 Ib) of generic portland
cement. Fully 100 % of the portland
cement is replaced by SFC.
1 kg (2.2 Ib) of slag cement is
equivalent to 1 kg (2.2 Ib) of generic
portland cement. The following
substitution ratios of slag cement for
portland cement are used: 20 %,
35 %, and 50 %.
1 kg (2.2 Ib) of Alpena Portland
Type I cement is equivalent to 1 kg
(2.2 Ib) of generic portland cement
1kg (2.2 Ib) of BlockSet is
equivalent to 1 kg (2.2 Ib) of generic
portland cement. Forty percent
(40 %) of the portland cement is
replaced by BlockSet.
1 kg (2.2 Ib) of Alpena Portland
Type I cement is equivalent to 1 kg
(2.2 Ib) of generic portland cement
The detailed environmental performance data for these product may be viewed by opening the
following files under the File/Open menu item in the BEES software:
• A1030J.DBF—Silica Fume Cement for Slabs
• A1030L.DBF—NewCem Slag Cement (20 %) for Slabs
• A1030M.DBF—NewCem Slag Cement (35 %) for Slabs
• A1030N.DBF—NewCem Slag Cement (50 %) for Slabs
• A1030P.DBF—Portland Type I Cement for Slabs
• A2020J.DBF—Silica Fume Cement for Basement Walls
• A2020L.DBF—NewCem Slag Cement (20 %) for Basement Walls
• A2020M.DBF—NewCem Slag Cement (35 %) for Basement Walls
53
-------
• A2020N.DBF—NewCem Slag Cement (50 %) for Basement Walls
• A2020O.DBF—BlockSet for Basement Walls
• A2020P.DBF—Portland Type I Cement for Basement Walls
• B101 IS.DBF—Silica Fume Cement (4KSI) for Beams
• B1011U.DBF—NewCem Slag Cement 4KSI (20 %) for Beams
• B1011V.DBF—NewCem Slag Cement 4KSI (35 %) for Beams
• B1011W.DBF—NewCem Slag Cement 4KSI (50 %) for Beams
• B1011X.DBF—Silica Fume Cement (5KSI) for Beams
• B1011Z.DBF—NewCem Slag Cement 5KSI (20 %) for Beams
• B1011AA.DBF—NewCem Slag Cement 5KSI (35 %) for Beams
• B1011BB.DBF—NewCem Slag Cement 5KSI (50 %) for Beams
• B1011CC.DBF—Portland Type I Cement 4KSI for Beams
• B1011DD.DBF—Portland Type I Cement 5KSI for Beams
• B1012S.DBF—Silica Fume Cement (4KSI) for Columns
• B1012U.DBF—NewCem Slag Cement 4KSI (20 %) for Columns
• B1012V.DBF—NewCem Slag Cement 4KSI (35 %) for Columns
• B1012W.DBF—NewCem Slag Cement 4KSI (50 %) for Columns
• B1012X.DBF—Silica Fume Cement (5KSI) for Columns
• B1012Z.DBF—NewCem Slag Cement 5KSI (20 %) for Columns
• B1012AA.DBF—NewCem Slag Cement 5KSI (35 %) for Columns
• B1012BB.DBF—NewCem Slag Cement 5KSI (50 %) for Columns
• B1012CC.DBF—Portland Type I Cement 4KSI for Columns
• B1012DD.DBF—Portland Type I Cement 5KSI for Columns
54
-------
• G2022G.DBF—Alpena Type I Cement for Parking Lot Paving
Flow Diagram
The flow diagram below shows the major elements of the production of this product as it is
currently modeled for BEES.
Lafarge North America Concrete Products
Transport to
Bldg Site
.. Functional Unit of
Concrete Products
A :
Raw Material
Transport
f Ready-Mix ^ Process
Plant Energy
T
i . 1 k ji 1 k
Process
Enerav ^
Lafarge
Products
^
9 Production
Transport ' l
Coarse Other
Fine Aggregate Aggregate |nputs
Production Production Production
4k J k 1 L 1 L J k A J k j k
Sand Clay Limestone
Production Production Production
Silica Fume Fly Ash Gypsum Slag Iron
Production Production Production Production Production
Figure 3.3: Lafarge North America Concrete Products System Boundaries
Raw Materials
The Lafarge products are comprised of the raw materials given in the Table below.
55
-------
Constituent
Limestone
Clay
Silica Fume
Sand
Gypsum
Slag
Fly Ash
Iron source/scrap
Silica Fume
Cement
72%
16%
5%
3%
3%
—
<0.01 %
1%
Slag
Cement
—
—
—
—
—
100 %
—
—
BlockSet
76%
16%
—
3%
3%
—
<0.01 %
1%
Alpena Portland
Ty_p_eJ_
91%
—
—
3%
—
—
5%
1%
Clay and limestone. Energy consumption and air emissions data for clay and limestone
production were provided by Construction Technology Laboratories, Inc. as part of the overall
cement plant data collected for Lafarge's Alpena site, and take into account fuel combustion,
quarry operations, and haul roads.
Silica fume. Silica fume is a by-product of the metallurgical processes used in the production of
silicon metals. It is called "fume" because it is an extremely fine smoke-like particulate material.
Because it is both pozzolanic and extremely fine (about 100 times finer than cement particles),
silica fume may be used to considerable advantage as a supplementary cementitious material in
Portland cement concrete. Silica fume has been used in the North American cement and
concrete industry for over 25 years and can be used in concretes to withstand aggressive
exposure conditions. Transportation of the silica fume to the electric furnace is accounted for in
the model.
Sand and gypsum. Sand production takes into account energy combustion, waste production,
and air emissions from fuel combustion and quarry operations. Gypsum production takes into
account electricity and diesel fuel consumption used in surface mining and processing, as well as
air emissions and waste production. Data for both of these materials are based on the SimaPro
database.
Slag. Slag is a waste material from the blast furnace during the production of pig iron. Blast
furnaces, which produce iron from iron ore in the presence of limestone or dolomite fluxes,
produce a molten slag. This slag is tapped off the furnace separately from the iron.
Fly ash. Fly ash comes from coal-fired, electricity-generating power plants. These power plants
grind coal to a fine powder before it is burned. Fly ash - the mineral residue produced by
burning coal - is captured from the power plant's exhaust gases and collected for use. Fly ash
particles are nearly spherical in shape, allowing them to flow and blend freely in mixtures, one of
the properties making fly ash a desirable admixture for concrete. In LCA terms, this waste
byproduct from coal combustion is assumed to be an environmentally "free" input material.
However, transport of the fly ash from the production site is included.
56
-------
Iron. The iron source for the Paulding site is mill scale, a by-product from hot rolling steel. It is
treated as scrap iron with no upstream burdens since it is a byproduct, but transportation of the
material is accounted for.
Manufacturing
Energy requirements and emissions. The Paulding site uses electricity, petroleum coke, diesel
oil, and fuel-quality waste (primarily solvents) as energy sources to produce silica fume cement,
BlockSet, and cement dust. Fuel-quality waste is the largest source of energy for the plant. Its
upstream production is modeled as being "free," but its combustion emissions are accounted for
(using the U.S. LCI Database's fuel oil combustion data). The Alpena site uses electricity, coke,
coal, diesel oil, fuel oil, and gasoline as energy sources to produce Portland Type I cement.
To prepare the slag for use in concrete, slag is quenched with water and is ground. Since the
water evaporates, there is no effluent run off. Water, electricity, and natural gas consumption
associated with this process are taken into account. All energy and electricity data are based on
the U.S. LCI Database.
Transportation. Transportation distances for the raw materials to the manufacturing site were
provided by Lafarge. Clay and limestone are hauled 1.61 km (1 mi) to the Paulding cement plant
and 3.22 km (2 mi) to the Alpena site. Silica fume is transported to the Paulding plant 241 km
(150 mi). Sand is transported to the Paulding and Alpena plants 80 km (50 mi) and 16 km (10
mi), respectively. Gypsum is transported to the Paulding plant 97 km (60 mi). Slag and iron are
transported 32 km (20 mi). Fly ash is transported by rail 322 km (200 mi). With the exception
of fly ash, materials are transported by diesel truck. Both diesel truck and rail transport are
modeled based on the U.S. LCI Database.
Transportation
Transportation of finished products to the building site is evaluated based on the same
parameters given for the generic counterparts to Lafarge products. All products are shipped by
diesel truck as modeled in the U.S. LCI Database. Emissions from transportation allocated to
each product depend on the overall weight of the product.
Installation and Use
Installing each of the BEES concrete applications requires plywood forms and steel
reinforcement. Refer to the documentation on generic portland cement concrete products for a
full description of the modeling of these installation materials.
End of Life
Beams, columns, basement walls, and slabs are all assumed to have 100-year lifetimes. Concrete
parking lot paving is assumed to last 30 years. Since the BEES model for parking lot paving
accounts for a 50-year use period, two concrete installations are made.
57
-------
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants, SimaPro 6.0LCA Software. 2005. The Netherlands.
Industry Reference
Oscar Tavares, Lafarge North America (2002)
3.2 Roof and Wall Sheathing
3.2.1 Generic Oriented Strand Board Sheathing
Oriented strand board (OSB) is made from strands of low density hardwoods and softwoods.
OSB sheathing is a structural building material used for residential and commercial construction.
The OSB panels must be grade-stamped to meet building code. Each panel has a third party
certification and a grade stamp that provides such information as the grading agency, the
manufacturer, the product type (in this case, sheathing), wood species, adhesive type, the
allowable roof and floor spans, and panel thickness. A wax, primarily a petroleum-based wax, is
used as an additive to OSB to provide temporary water holdout. Phenol-formaldehyde and
methylene-diphenyl-isocyanate (MDI) resins are used as binder materials to hold the strands
together.
For residential construction, the building code requirement is typically for a rated sheathing
panel of either OSB or plywood of 0.95 cm (3/8 in) thickness when sheathing is required, such as
for shear wall sections; however, common practice is to use sheathing thicknesses greater than
specified by code, which is referred to as "code plus." The most common sheathing thickness
for OSB is 1.1 cm (7/16 in).
For the BEES system, 0.09 m2 (1 ft2) of OSB measuring 1.1-cm (7/16-in) thick is studied. BEES
performance data are provided for both roof and wall sheathing; life-cycle costs and
environmental performance data are essentially the same for the two applications. The detailed
environmental performance data for this product may be viewed by opening the file
B1020A.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
58
-------
OSB Production
Transport to
Construction
Site
^
s
Functional Unit of
OSB Sheathing
Figure 3.4: OSB Sheathing System Boundaries
Raw Materials
The OSB data for BEES are based on a study performed by CORRIM.69 The following Table
shows the constituents of 0.09 m2 (1 ft2) of 1.1 cm (7/16 in) thick OSB sheathing, in terms of
percentage of final product.
Table 3.8: OSB Constituents
Constituent Mass Mass Fraction (%)
Wood
PF resin
MDI resin
Wax
Totals
6.76(1.38)
0.237(0.049)
0.043 (0.009)
7l5(L46)
94.5
0.66
100
Kline, D.E. "Southeastern oriented strandboard production," Module A, Life Cycle Environmental
Performance of Renewable Building Materials in the Context of Residential Construction (Seattle, WA: Consortium
for Research on Renewable Industrial Materials-CORRIM, Inc)/University of Washington, 2004). Found at:
http://www.corrim.org/reports.
59
-------
The BEES model includes timber production, which includes raising seedlings, planting,
fertilizer, and harvesting. Energy use and life cycle data on timber production are based on a
study by CORRIM of tree production and harvesting in the Southeastern United States for
southern pine.70 The growing and harvesting of wood is modeled as a composite comprised of a
mix of low-, medium-, and high-intensity managed timber. Energy use includes electricity for
greenhouses to grow seedlings, gasoline for chain saws, diesel fuel for the harvesting mechanical
equipment, and a small amount of fertilizer. Fertilizer production data is adapted from European
data in the U.S. LCI Database. Emissions from tractors and those associated with production of
diesel fuel as well as production and delivery of electricity are included and taken from the U.S.
LCI Database. Electricity use for greenhouse operation is based on the grids for the regions
where the seedlings are grown. The mix of wood resources for the OSB mills is southern pine
softwood (75 %) and several different southern hardwoods (25 %). The average density of this
mix, on an oven-dry basis, is 558 kg/m3 (34.82 lb/ft3).
BEES modeling accounts for the absorption of carbon dioxide by trees as they grow; the carbon
becomes part of the wood, and the oxygen is released to the atmosphere. The "uptake" of carbon
dioxide from the atmosphere during the growth of timber is about 1.84 kg (4.06 Ib) of carbon
dioxide per kilogram of harvested wood (oven-dry weight).
Data representing the production of the phenol formaldehyde (PF) resin and MDI are derived
from American Chemistry Council 2006 data developed for submission to the U.S. LCI
Database, The ATHENA Institute, and the SimaPro database. The wax used in the production of
OSB is assumed to be petroleum wax. Production of the petroleum wax is based on the SimaPro
database and includes the extraction, transportation, and refining of crude oil into petroleum
wax. Electricity for greenhouse operation is regional for the Southeastern United States, whereas
electricity for fertilizer production and other inputs is a U.S. average based on fuel source
breakdown values.
Manufacturing
Energy Requirements. The energy for the OSB manufacturing process comes from burning the
wood waste, which was generated during processing, and use of natural gas. Other fuels used
include propane, diesel, fuel oil, and gasoline to operate mechanical equipment, as well as
purchased electricity. The site energy and electricity used are shown in the Table below.
70 Bowyer, J., et al., Phase I Final Report: Life Cycle Environmental Performance of Renewable Building
Materials in the Context of Residential Construction. (Seattle, WA: Consortium for Research on Renewable
Industrial Materials-CORRIM, Inc./University of Washington, 2004). Found at http://www.corrim.org/reports.
600+ pp.; data also submitted to US LCI Database.
60
-------
Energy Carrier
Units
Quantity, 0.95 cm
Electricity - Southeast Grid
Natural Gas
Diesel fuel
Distillate Fuel Oil
LPG
Gasoline
Hogfuel/Biomass (50 % moisture)
MJ/m2 (kWh/ft2)
MJ/m2 (ft3/ft2)
L/m2 (gal/ft2)
L/m2 (gal/ft2)
L/m2 (gal/ft2)
MJ/m2 (gal/ft2)
kg/m2 (lb/ft2)
7.360(190)
8.743 (747)
0.19(0.01)
7.74(0.19)
0.030(0.71)
0.004 (0.03)
4 078 (836)
Emissions. The process emissions from the OSB manufacturing process (e.g., volatile organic
compound (VOC) emissions from drying the OSB) are based on CORRIM data, as reported in
the Table below and in the U.S. LCI Database. With the exception of wood residue combustion,
emissions from energy combustion at the plant are included upstream.
^fl^fe^/£;^SB_Mifl^M^^ftiw2gj^^_^H*£i22L
Air Emission Quantity in kg/nfflb/ft2),
Particulates (unspecified)
VOC (unspecified)
Carbon Dioxide
(biomass)
Acetaldehyde
Acrolein
Methanol
Phenol
Formaldehyde
3.03E-03 (0.62)
1.06E-02(2.18)
1.17E-01 (24)
6.34E-04(0.13)
2.29E-04 (0.047)
1.95E-03 (0.4)
1.17E-04 (0.024)
5.37E-04(0.11)
Transportation. For transportation of raw materials to the manufacturing plant, BEES assumes
truck transportation of 143 km (89 mi) for wood timber, 932 km (579 mi) for PF resin, 1328 km
(825 mi) for MDI resin, and 1149 km (714 mi) for the wax, based on CORRIM survey data. The
tailpipe emissions from the trucks and the emissions from producing the fuel used in the trucks
are taken into account and are based on the U.S. LCI Database. The delivery distances are one-
way with an empty backhaul. For shipping weights to the OSB mill, the moisture content of the
logs is taken into account. The PF resin is shipped at 50 % solids (50 % water) on a wet basis.
MDI resin and wax are transported as their stated weight.
Waste. There is essentially no solid waste from the OSB manufacturing process. All the input
resin (mainly PF resin with some MDI resin) and the wax can be assumed to go into the final
product and the excess wood material is assumed to be burned on site for fuel.
61
-------
Transportation
Transportation of OSB by heavy-duty truck to the building site is modeled as a variable of the
BEES system. To determine the shipping weight of OSB, the model assumes the product has a
5 % moisture content.
Installation
During installation, 1.5 % of the mass of the product is assumed to be lost as waste, which is sent
to the landfill. For walls and roofs, OSB is installed using nails. Approximately 0.0024 kg
(0.0053 Ib) of steel nails are used per ft2 of OSB. Steel h-clips are used in addition to nails for
roof sheathing, although only a small number of clips are required per panel. H-clip production
is not included within the boundary of the model.
Use
Based on U.S. Census data, the mid-service life of OSB in the United States is over 85 years. As
a conservative estimate, CORRIM—and BEES—use a product life of 75 years.
There is no routine maintenance for sheathing over its lifetime. Roofing material and siding over
the sheathing should be replaced as needed. Sheathing would only be replaced when the framing
is replaced, so no replacement is assumed.
End of Life
All of the OSB is assumed to be landfilled at end of life.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Kline, D.E. "Southeastern oriented strandboard production," Module A, Life Cycle
Environmental Performance of Renewable Building Materials in the Context of Residential
Construction (Seattle, WA: Consortium for Research on Renewable Industrial Materials.
(CORRIM, Inc.)/University of Washington, 2004): Found at http://www.corrim.org/reports.
Bowyer, J., et. al., Phase I Final Report: Life Cycle Environmental Performance of Renewable
Building Materials in the Context of Residential Construction. (Seattle, WA: Consortium for
Research on Renewable Industrial Materials. (CORRIM, Inc.)/University of Washington,
2004) Found at http://www.corrim.org/reports.
Industry Contacts
Jim Wilson, Oregon State University/CORRIM, Inc. (August 2005-Jan 2006)
62
-------
3.2.2 Generic Plywood Sheathing
Plywood sheathing is a structural building material used for residential and commercial
construction. The panels must be grade-stamped to meet building code. Each panel has a third
party certification, a grade stamp that provides such information as the grading agency, the
manufacturer, the product type (in this case, sheathing), wood species, adhesive type, the
allowable roof and floor spans, and panel thickness.
Plywood sheathing is made from lower density softwoods. Phenol formaldehyde (PF) is used as
an adhesive in the manufacturing process. The flow diagram below shows the major elements of
plywood sheathing production.
For residential construction, the building code requirement typically is for a rated sheathing
panel of either OSB or plywood of 0.95 cm (3/8 in) thickness when sheathing is required, as for
shear wall sections; however, the common practice is to use sheathing thicknesses greater than
code, which is referred to as "code plus." The most common sheathing thicknesses are 1.2 cm
(15/32 in) for plywood and 1.1 cm (7/16 in) for OSB.
For the BEES system, 0.09 m2 (1 ft2) of 1.2 cm (15/32 in) thick plywood panel is studied. BEES
performance data are provided for both roof and wall sheathing. Life-cycle costs and
environmental performance data are essentially the same for both products. The detailed
environmental performance data for this product may be viewed by opening the file
B1020B.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
63
-------
Plywood Production
Transport to
Construction
Site
^
s
Functional Unit of
Plywood Sheathing
Figure 3.5: Plywood Sheathing System Boundaries
Raw Materials
The plywood data for BEES are based on two CORRIM resources.71'72 The dry weight of
plywood is assumed to be 521 kg/m3 (32.5 Ib/ft3). The Table below shows the constituents of
0.09 m2 (1 ft2) of 1.2 cm (15/32 in) thick plywood in terms of their final product percentages.
71 Bowyer, I, et al., Phase I Final Report: Life Cycle Environmental Performance of Renewable Building
Materials in the Context of Residential Construction. (Seattle, WA: Consortium for Research on Renewable
Industrial Materials-CORRIM, Inc./University of Washington, 2004). Found at: http://www.corrim.org/reports:
data also submitted to US LCI Database.
72 www.corrim.org
64
-------
Constituent Mass Mass Fraction (%)
Wood 5.96(1.22) 97
PF Resin 0.108(0.022) 1.8
Extender 0.065(0.013) 1.1
JTotal 65(L23) 100
Softwood plywood sheathing is primarily produced in the Pacific Northwest and the
Southeastern United States. For the Pacific Northwest the species of wood used are Douglas Fir
and Western Hemlock, while for the Southeast the wood species is Southern Yellow Pine, which
is actually a group of six different softwood species.
The data for growing and harvesting softwood logs for a composite forest management scenario
of the Pacific Northwest (PNW) and Southeastern United States (SE) is found in the CORRIM
studies. The growing and harvesting of wood is comprised of a mix of low-, medium-, and high-
intensity managed timber. Energy use for wood production includes electricity for greenhouses
to grow seedlings, gasoline for chain saws, diesel fuel for harvesting mechanical equipment, and
a small amount of fertilizer. Emissions associated with production and combustion of gasoline
and diesel fuel and those for the production and delivery of electricity are based on the U.S. LCI
Database. Fertilizer production data is adapted from European data in the U.S. LCI Database.
Electricity use for greenhouse operation is based on the grids for the regions where the seedlings
are grown, while the U.S. average electricity grid is used for fertilizer production. CORRIM
equally weights production in PNW and SE
BEES modeling accounts for the absorption of carbon dioxide by trees as they grow; the carbon
becomes part of the wood, and the oxygen is released to the atmosphere. The "uptake" of carbon
dioxide from the atmosphere during the growth of timber is about 1.84 kg (4.06 Ib) of carbon
dioxide per kilogram of harvested wood (oven-dry weight).
The glue used in bonding plywood consists of PF resin in liquid form combined with extender
(which can be a dry agrifiber such as walnut shells or corn husks) and an alkaline catalyst. Data
for the production of PF resin comes from the U.S. LCI Database. Weights of resin, extender and
catalyst are given on a 100 % solids basis (moisture content not considered).
Manufacturing
Energy Requirements. Manufacturing to produce oven-dry plywood includes several process
steps including debarking, log conditioning, production of green veneer, production of dry
veneer, pressing and lay-up, and trimming and sawing.
The energy for the plywood manufacturing process is generated from burning wood waste and a
small amount of natural gas, and from purchased electricity. Electricity production emissions are
based on an average of regional electricity grids for PNW and SE. A small amount of fuel is
used for log haulers and forklifts at the plywood mill, and consists of liquid petroleum gas
65
-------
(propane) and diesel. The allocated site energy and electricity use are broken down in the
following Table for SE and PNW plywood production. The BEES model uses an equally-
weighted average for the final product~1.2 cm (15/32 in) thick plywood:
T_able_3.12: P^wood_Production_Energy_
Energy Carrier
Electricity - Regional Grid
Natural Gas
Diesel Fuel
LPG
Hogfuel/Biomass (oven-dry)
Units
MJ/m2 (kWh/ft2)
MJ/m2 (ft3/ft2)
L/m2 (gal/ft2)
L/m2 (gal/ft2)
kg/m2(lb/ft2)
Plywood from
SE
4.26(0.11)
3.04(0.26)
0.041 (0.001)
0.015 (0.0004)
1.41 (0.29)
Plywood from
PNW
4.26(0.11)
1.64(0.14)
0.041 (0.001)
0.011 (0.0003)
0.88(0.18)
Emissions. The allocated air emissions from the plywood manufacturing process are based on
the CORRIM study and reported in the Table below. Allocation is based on mass and a multi-
unit process analysis to correctly assign burdens. The VOC emissions are from the drying of
wood veneer.
Tabl£ 3.13: PJgwood^Productiori Emission^
Air Emission Plywood from SE Plywood from PNW
Particulates (unspecified)
VOC (unspecified)
Acetaldehyde
Acrolein
Methanol
Phenol
Formaldehyde
Acetone
Alpha-pinene
Beta-pinene
Limonene
Methyl-ethyl ketone
3.12E-03 (6.40E-04)
1.32E-03(2.70E-04)
2.39E-05 (4.90E-06)
7.32E-04(1.50E-04)
8.78E-06(1.80E-06)
1.17E-05(2.40E-06)
3.42E-05(7.00E-06)
4.88E-04(1.00E-04)
1.95E-04(4.00E-05)
5.37E-05(1.10E-05)
3.46E-06(7.10E-07)
2.00E-03 (4.10E-04)
3.95E-03(8.10E-04)
6.83E-05(1.40E-05)
2.78E-03 (5.70E-04)
8.30E-04(1.70E-04)
1.85E-05(3.80E-06)
1.37E-04(2.80E-05)
3.03E-05 (6.20E-06)
4.54E-04 (9.30E-05)
1.76E-04(3.60E-05)
4.88E-05(1.00E-05)
7.32E-06(1.50E-06)
Transportation. For transportation of raw materials to the plywood manufacturing plant,
CORRIM surveys report truck transportation of 126 km (78 mi) for harvested wood and truck
transportation of 177 km (110 mi) for the resin. The weights of materials shipped to the plywood
mill reflect the actual moisture content rather than the oven-dry weight in the plywood product.
Both the logs and the PF resin are shipped with 50 % moisture content on a wet basis (50 %
water). The delivery distances are one-way with an empty backhaul.
66
-------
Waste. There is no solid waste from the plywood manufacturing process. The PF resin is
assumed to go into the final product and all the wood is assumed to go into plywood or co-
products. Co-products include materials such as peeler core, veneer clippings, panel trim, and
sawdust, as well as wood fuels in the form of bark and wood waste that are burned on site.
Transportation
Transportation of the plywood by heavy-duty truck to the building site is modeled as a variable
of the BEES system
Installation
During installation, 1.5 % of the mass of the product is assumed to be lost as waste which is sent
to the landfill - although wood construction materials are increasingly being recycled into other
products. For walls and roofs, plywood is installed using nails. Approximately 0.0024 kg
(0.0053 Ib) of steel nails are used per ft2 of plywood. Steel h-clips are used in addition to nails
for roof sheathing, although only a small number of clips are required per panel. H-clip
production is not included within the boundary of the model.
Use
Based on U.S. Census data, the mid-service life of plywood sheathing in the United States is
over 85 years. As a conservative estimate, CORRIM uses a product life of 75 years.
There is no routine maintenance required for sheathing over its lifetime. Roofing material and
siding over the sheathing should be replaced as needed. Sheathing would only be replaced when
the framing is replaced; no replacement is assumed.
End of Life
All of the plywood is assumed to be disposed of in a landfill at end of life.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Bowyer, J., et. al., Phase I Final Report: Life Cycle Environmental Performance of Renewable
Building Materials in the Context of Residential Construction. (Seattle, WA: Consortium for
Research on Renewable Industrial Materials. (CORRIM, Inc.)/University of Washington,
2004). Found at: http://www.corrim.org/reports.
Industry Contacts
Jim Wilson, Oregon State University/CORRIM, Inc. (August 2005-Jan 2006)
67
-------
3.3 Exterior Wall Systems
3.3.1 CENTRIA Formawall Insulated Composite Panel
Based in Moon Township, Pennsylvania, near Pittsburgh, CENTRIA is an international company
specializing in the manufacture of metal building products and systems for nonresidential walls,
roofs, and electrical cellular floors. CENTRIA's Formawall Insulated Composite Panel is a
factory foam-installed metal panel system with a rigid insulating, CFC-free, foam core. Its one-
piece design permits a complete, thermally efficient exterior wall that can be installed quickly.
Its design provides air, water, and vapor barriers. CENTRIA Formawall Insulated Panels are
available in a selection of finishes and thicknesses and come in a range of profile options for new
and retrofit buildings. CENTRIA Formawall Insulated Panels provide an interior wall, vapor
barrier, thermal insulation, and exterior metal substrate. Besides stainless steel fasteners, no
additional materials, such as sheathing or more insulation, typically are required. For this reason,
CENTRIA Formawall is considered an exterior wall system as opposed to a wall finish.
The detailed environmental performance data for this product may be viewed by opening the file
B2010A.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
68
-------
CENTRIA Formawal Insulated Composite Panel
True
Transport to
Bid Site
Functional Unit of
CENTRIA
Formawal
En -o-Lif
Pentan
PUR precursor
resin
Figure 3. 6: CENTRIA Formawall Insulated Composite Panel System Boundaries
Raw Materials
For BEES, a typical finish made of painted galvanized steel skin encases a CFC-free expanded
polyurethane (PUR) foam insulation layer. The following Table presents the major constituents
of a CENTRIA Formawall Insulated Panel, in terms of their mass per ft2.
Table 3.14: CENTRIA FormawalllnsulatedCo^mosUePanelComthuen^^
_ Cjmstituent -Ml!!^^
Galvanized steel
Expanded PUR foam
Solyent-basedpaint
1 1.9 (2.43)
3.0(0.61)
0.05 (0.01)
79.7
20
0.3
The rigid PUR foam, blown with pentane, is produced with 59 % diphenylmethane diisocyanate
(MDI) resin and 41 % rigid poly ether polyol resin. The amount of pentane used for PUR
blowing is 0.024 kg (0.054 Ib) per Ib of foam. Data for pentane comes from APME73 and data
for the resins from American Chemistry Council 2006 data developed for submission to the U.S.
LCI Database.
73
Boustead, I. (Association of Plastics Manufacturers of Europe, March 2005), Tables 1-9.
69
-------
Galvanized steel comes from an LCI study by the International Iron and Steel Institute using
worldwide facility (primary) data from 1999 and 2000. 74 Data on production of components in
the solvent paint comes from elements of the SimaPro database.
Manufacturing
Energy Requirements and Emissions. Manufacturing energy is used for painting the steel,
producing the foam, and assembling the components into the CENTRIA Formawall Insulated
Panel. The following Table presents the manufacturing energy per 0.09 m2 (1 ft2) of CENTRIA
Formawall Insulated Panel:
Table 3.15: Energy Reqmniinentsjor^^ Panel Production
Electricity 0.9 kWh
Natural gas 180ft3
All energy production and consumption data come from the U.S. LCI Database. The emissions
associated with the production process are provided in the Table below, and result mainly from
PUR foam blowing and painting.
Table 3. 1 6: Production
Emission
Methylene Chloride 1 .3 E-2 (2.7 E-3)
Pentane 1.1 E-2 (2.3 E-3)
Toluene 1.4E-5 (2.8 E-6)
Naphthalene 1.5 E-7 (3.0 E-8)
Formaldehyde 2.0 E-7 (4.0 E-8)
Acetone 1.7 E-6 (3.5 E-7)
Methyl Ethyl Ketone (MEK) 4.3 E-5 (8.9 E-6)
Dimethyl phthalate 8.8 E-6 (1.8 E-6)
Glycol Ethers 2.8 E-5 (5.8 E-6)
Methyl isobutyl ketone 2.3 E-6 (4.7 E-7)
Xylene (mixed isomers) 1.7 E-5 (3.4 E-6)
Isophorone 5.4 E-5 (1.1 E-5)
Ethyl benzene 1 .6 E-6 (3 .2 E-7)
A small amount of manufacturing waste is produced: 0.002 kg (0.004 Ib) per ft2 of CENTRIA
Formawall Insulated Composite Panel.
Transportation. The steel is transported approximately 80 km (50 mi) to a facility where it is
painted, and then it is transported approximately 1 449 km (900 mi) to the CENTRIA facility in
74 International Iron and Steel Institute (IISI) LCI data sheets provided by an industry contact at Steel Recycling
Institute. Data are from worldwide production of steel products, with use of 1999-2000 plant data.
70
-------
Arkansas. The polyether polyol and MDI resin are transported approximately 1 288 km (800 mi)
and 725 km (450 mi), respectively, to CENTRIA. These are all transported by diesel truck, with
burdens modeled using the U.S. LCI Database.
Transportation
CENTRIA Formawall Insulated Panels are transported an average of 805 km (500 mi) by diesel
truck to the building site.
Installation
Installation of CENTRIA Formawall Insulated Composite Panels entails attaching the panel
directly onto the building framing with Type 305 stainless steel, #14 x 1-3/4 fasteners. Eight
fasteners are used per 9 m2 (100 ft2). At 0.01 kg (0.02 Ib) each, 0.07 kg (0.16 Ib) of fasteners are
used per 9 m2 (100 ft2), or 0.0016 Ib/ ft2. The electricity used during installation is 0.00021 kWh/
ft2. The fasteners are transported an average of 160 km (100 mi) to the installation site.
Because CENTRIA Formawall panels are built according to pre-designed building
specifications, they arrive at the site fully measured and ready for installation, and only rarely is
there a need to trim the product to fit for correct installation. Because any waste would be such a
small percentage of total material use, no installation waste is modeled for BEES.
Use
The product is assumed to have a useful life of 60 years. A building using CENTRIA Formawall
Insulated Panels typically needs no additional insulation,
End of Life
It is assumed that CENTRIA Formawall Insulated Panels are waste at end of life and are sent to
a landfill. CENTRIA has begun to look at possibilities of a steel recovery process for the
CENTRIA Formawall panel at the end of its life. In any event, CENTRIA Formawall panels
have not been in existence long enough for CENTRIA to assess if this recovery will occur during
decommissioning.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 7.0LCA Software. 2005. The Netherlands.
Boustead, I, Eco-profiles of the European Plastics Industry: Pentane (Association of Plastics
Manufacturers of Europe, March 2005), Tables 1-9.
International Iron and Steel Institute (IISI), LCI data sheets provided by an industry contact at
Steel Recycling Institute.
Industry Contacts
Mark A. Thimons, CENTRIA (September 2006)
71
-------
3.4 Exterior Wall Finishes
3.4.1 Generic Brick & Mortar
Brick is a masonry unit of clay or shale, formed into a rectangular shape while plastic, cored, and
then burned or fired in a kiln. Mortar is used to bond the bricks into a single unit. Facing brick is
used on exterior walls.
The BEES model for brick in mortar evaluates fired clay facing brick. The brick is cored prior to
being fired, which removes about 25 % to 30 % of the clay material. The actual dimensions of
the brick are 9.2 cm x 5.7 cm x 19.4 cm (3.6 in x 2.2 in x 7.62 in). A cored and fired brick of this
size weighs 1.86 kg (4.10 Ib). The nominal dimensions of the brick including the mortar joint are
9.2 cm x 6.8 cm x 20 cm (3.6 in x 22/3 in x 8 in). The brick is assumed to be installed with Type
N mortar, which has a density of 1840 kg/m3 (115 Ib/ft3), with an air content of at least 20 %.
Masonry is typically measured on the basis of wall area (m2 or ft2). A brick wall is assumed to be
80 % brick and 20 % mortar by surface area.
While buildings with brick and mortar finishes require insulation, the finish does provide a
thermal resistance value of about R-2. The BEES user has the option of accounting for the
resulting energy saved, relative to other exterior wall finishes, over the 50-year use period. This
is explained in more detail under Use.
The detailed environmental performance data for this product may be viewed by opening the file
B2011 A.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
72
-------
Brick and Mortar
Figure 3.7: Brick and Mortar System Boundaries
Raw Materials
Brick uses virtually 100 % mined clay or shale. Bottom ash, a post-industrial recycled material,
is the most widely used recycled material that is added to the clay during brick production.
Typical replacement of clay or shale inputs is 0.8 % bottom ash by mass.
Table 3.17: Fired Brick Constituents
Constituent
Mass Fraction
Clay
Bottom Ash
99.2
0.8
All material removed in the manufacturing process is returned to the manufacturing stream.
Fired product that is scrapped is used as grog75 in brick manufacturing or for other uses such as
landscape chips and roadbed.
Type N mortar consists of 1 part masonry cement (by volume fraction), 3 parts sand,76 and 6.3 L
75 Grog is previously-fired ceramic material, typically from ground brick. It is included in the brick body to
reduce drying shrinkage or provide a more open texture to the fired brick.
76 Based on ASTM Specification C270-96.
73
-------
(1.7 gal) of water. The raw material use for masonry cement is based on Type N masonry
cement, and its constituents are shown below.
— Masonry Cement^ Constituent^
„ . Mass Fraction
Constituent f0/.
Portland Cement Clinker 50.0
Limestone 47.5
Gyp_sum 2.5
The flow diagram for brick and mortar shows only the solid components of mortar. Some water
in mortar is chemically bound, so there is some net consumption of water—based on 25 % by
weight for hydration, approximately 230 kg/m3 (14 lb/ft3) of water is used. Production of the raw
materials for brick and mortar are based on the SimaPro LCA database and the U.S. LCI
Database.
Manufacturing
Energy Requirements and Emissions. The energy requirements for brick production are listed
in the Table below. These figures include the drying and firing production steps only, based on
the latest Brick Industry Association survey stating that these are the most important steps in
terms of energy use. Environmental flows resulting from the production of the different types of
fuel are based on the U.S. LCI Database.
Table 3.19: Energy R£^uir^ments_^or_ Brick^ Manufacturing
Carrier
Natural Gas °-028 m' (°-987 ft3)
Grid Electricity 0.0810 MJ (0.0225 kWh)
Brick production is distributed across U.S. Census Regions as given below.
74
-------
Pacific 2.8 %
Mountain 3.5 %
West South Central 17.8%
East South Central 17.9 %
South Atlantic 39.6 %
West North Central 4.1%
East North Central 8.1%
Middle Atlantic 5.4%
New England 0.8%
A blend of grid electricity sources are used to represent this distribution of manufacturing
facilities.
Emissions for brick firing and drying are based on AP-42 data for emissions from brick
manufacturing for each manufacturing technology and type of fuel burned.77'78
Water Consumption. Water is used in the manufacturing process to impart plasticity to the raw
materials, which allows the brick to be formed. On average, approximately 20.5 % water by
weight is used and returned to the atmosphere in drying.
Transportation. Brick raw materials are typically transported less than 80 km (50 mi) by truck to
the brick plant.79
Waste. The manufacturing process generates no waste materials as all materials are reused in the
plant.
Transportation
Transportation of brick to the building site is modeled as a variable of the BEES system. Bricks
are assumed to be transported by truck and rail (84.7 % and 15.3 %, respectively) to the building
site.80
77 United States Environmental Protection Agency, "Brick and Structural Clay Product Manufacturing," Volume
I: Section 11.3, AP-42: Compilation of Air Pollutant Emission Factors(Washington, DC: US Environmental
Protection Agency, August 1997). Found at: http://www.epa.gov/ttn/chief/ap42/chll/final/clls03.pdf.
78 According to the Brick Industry Association (BIA), AP-42 emissions data are likely to be overstated, as at
least 30 brick plants have added emission control devices in the past five years, and all new plants (including at least
5 new plants completed in the past 5 years) include these emission control devices. However, no alternate emissions
data were made available by BIA.
79 An additional note regarding the production of bricks: according to BIA, brick companies have been cited for
their reclamation of spent clay pits. Examples include golf courses, wetlands, and land fills.
80 United States Environmental Protection Agency, "Brick and Structural Clay Product Manufacturing," Volume
I: Section 11.3, AP-42: Compilation of Air Pollutant Emission Factors(Washington, DC: US Environmental
Protection Agency, August 1997). Found at: http://www.epa.gov/ttn/chief/ap42/chll/final/clls03.pdf.
75
-------
Installation
Installation of brick and mortar primarily consists of manual labor; no energy use is modeled for
the installation phase. Losses during the installation phase are estimated to be 5 % of total
materials per ft2. Waste from the installation process is typically landfilled.
While sheathing, weather resistive barriers, and other ancillary materials may be required to
complete the exterior wall system, these materials are not included in the system boundaries for
BEES exterior wall finishes.
Use
Brick walls are often in service for more than 100 years. Older buildings are adapted to new
uses, with the existing brick walls included as a design feature. A useful life of 200 years is
assumed. Most brick walls have little maintenance. Repointing of mortar joints on portions of
the wall may be required after 25 years, but this minor maintenance step was not included within
the system boundary of the model.
It is important to consider thermal performance differences when assessing environmental and
economic performance for exterior wall finish product alternatives. Thermal performance affects
building heating and cooling loads, which in turn affect energy-related LCA inventory flows and
building energy costs over the BEES 50-year use stage.
For exterior wall finishes, thermal performance differences are optionally assessed for 14 U.S.
cities spread across a wide range of climate and fuel cost zones, and for electricity, distillate oil,
and natural gas heating fuel types (electricity is assumed for all cooling). When selecting wall
finish alternatives for analysis, if the BEES user chooses to account for thermal performance, he
or she selects the U.S. city closest to the building location and the building heating fuel type, so
that thermal performance differences may be customized to these important contributors to
building energy use.
Three BEES exterior wall finish products affect thermal performance: generic brick and mortar,
Dryvit Outsulation, and Dryvit Outsulation Plus. Assuming a thermal resistance value of R-13 is
required by code for exterior walls, then R-13 insulation on a brick and mortar wall will increase
its thermal performance to about R-15, and on a Dryvit Outsulation or Dryvit Outsulation Plus
wall, to about R-19. If the BEES user chooses to account for thermal performance, use energy
savings for these three products, over and above that provided by R-13 insulation, are accounted
for in the BEES results.81
End of Life
Demolition of brick walls at end of life typically is not done very carefully. The walls are
knocked down using equipment such as a wrecking ball or explosives, resulting in some loss of
brick. It is estimated that 75 % of the brick is recovered in usable form. The mortar is removed
by hand labor using chisels and hammers, typically at the demolition site. The cleaned brick is
sold for new construction, and the mortar and broken brick are taken to landfills.
81 Note that if generic brick and mortar and/or the two Dryvit products are the only alternatives being compared,
use energy savings are computed relative to the selected alternative with the lowest R-value.
76
-------
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database . 2005.
Golden, CO. Found at: http://www.nrel . gov/lci/database.
PRe Consultants: SimaPro 6.0LCA Software. 2005. The Netherlands.
United States Environmental Protection Agency, "Brick and Structural Clay Product
Manufacturing, " Volume I: Section 11.3, AP-42: Compilation of Air Pollutant Emission
Factors, (Washington, DC: U.S. Environmental Protection Agency, August 1997). Found at:
http://www.epa.gov/ttn/chief/ap42/chl 1/fmal/cl Is03.pdf.
ASTM International, C27 '0-06 Standard Specification for Mortar for Unit Masonry, (West
Conshohocken, PA, 2005).
Industry Contacts
J. Gregg Borchelt, P.E., Brick Industry Association (August-November 2005)
3.4.2 Generic Stucco
Stucco is cement plaster that can be used to cover exterior wall surfaces. Both portland cement
and masonry cement are used for the base and finish coats of stucco exterior walls. The densities
of the different types of stucco coats for portland cement (for a base coat Type C plaster, finish
coat Type F plaster) and masonry cement (for a base coat Type MS plaster, finish coat Type
FMS plaster) are shown in the Table below. Since no data on relative market shares of portland
cement and masonry cement stucco were available, life cycle data for the two stucco types were
averaged for use in the BEES model. Thus, each generic stucco coat (base or finish) is
represented by an average of the corresponding portland cement and masonry cement coats.
Table 3.20: Density of Stucco by
Density
Type of Stucco kg/nf'jib/ft3)
Portland Cement Base Coat C 1 830(114.18)
Portland Cement Finish Coat F 1 971 (122.97)
Masonry Cement Base Coat MS 1 907 (1 18.98)
The BEES model assumes a functional unit of 1 ft2 of stucco applied to a frame construction
(stucco applied over metal lath). This generally requires a 3-coat covering totaling 2.22 cm (7/8
in) in thickness. Coats 1 and 2 are each 0.95 cm (3/8 in) thick and the finish coat is 0.32 cm (1/8
in) thick.
The detailed environmental performance data for this product may be viewed by opening the file
B201 IB. DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagrams that follow show the major elements of the production of portland cement
stucco and masonry cement stucco exteriors.
77
-------
Portland Cement Stucco
I
L I
Hyd rated
Lime
Production
1 1
Portland
Cement
Production
Sand
Mning
i
1 I
Hyd rated
Lime
Production
> i
Portland
Cement
Production
Sand
Mning
Figure 3.8: Portland Cement Stucco System Boundaries
Masonry Cement Stucco
Transport to
Construction
Site
Functional Unit of
Stucco Exterior
Wall
End-of-Life
J
k J
Portland
Cement Clinker
Production
Lime
Prodi
i
stone
ction
Gypsum
Production
Figure 3.9: Masonry Cement Stucco System Boundaries
Raw Materials
The material composition of portland cement and masonry cement base coat and finish coat
78
-------
stuccos is shown in the following Table.
82
Tabl£3.21: Stucco Constituents^
Cementitious Materials (volume Sand
fraction) (volume
Constituent , fraction of
Portland Masonry ,. J . .
^ Lime cementitious
Cement Cement material)
Base Coat C 1 1.125 3.25
Finish Coat F 1 1.125 3
Base Coat MS 1 3.25
_FjnishCoatFMS 1 3
Masonry Cement Production. The raw material use for masonry cement is based on Type N
masonry cement, and its constituents are shown below.
Table_3.2_2: Masonry Cement Constituents
„ . Mass Fraction
Constituent (0/.
Portland Cement Clinker 50.0
Limestone 47.5
_Gyj)sum_ 2.5_
Production of raw material inputs for masonry cement (limestone and gypsum) and stucco (sand
and lime) are based on data from the U.S. LCI Database and the SimaPro database. The energy
requirements for masonry cement production are based on the energy required to grind and mix
the masonry cement constituents, as follows.
Table 3.23: ^«£r^ ^££Mirem£«|s ^r Masonry Cement _ Manufacturing
Fuel Use Manufacturing^ Energy
The only emissions from masonry cement production, aside from those due to the production of
the portland cement, are CC>2 emissions from the additional lime used to make the masonry
cement. According to the U.S. Greenhouse Gas Inventory:83
"During the cement production process, calcium carbonate (CaCO3) is heated in a cement kiln at a
82 Based on ASTM Specification C926-94.
83 U.S. Environmental Protection Agency, "Cement Manufacture (IPCC Source Category 2A1)," Chapter 4.2,
Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2004. (Washington, DC: U.S. Environmental
Protection Agency, April 2006). pp. 4-8 to 4-9.
79
-------
temperature of about 1 300 °C (2 400 °F) to form lime (i.e., calcium oxide or CaO) and CO2. This
process is known as calcination or calcining. Next, the lime is combined with silica-containing
materials to produce clinker (an intermediate product), with the earlier by-product CO2 being
released to the atmosphere. The clinker is then allowed to cool, mixed with a small amount of
gypsum, and used to make portland cement. The production of masonry cement from portland
cement requires additional lime and, thus, results in additional CO2 emissions. Masonry cement
requires additional lime over and above the lime used in clinker production. In particular,
nonplasticizer additives such as lime, slag, and shale are added to the cement, increasing its weight
by approximately five percent."
In the BEES model, lime accounts for approximately 47.5 % percent of the added weight. An
emission factor for this added lime can then be calculated by multiplying this value by the
emission factor for lime calcining, resulting in a factor of 0.44 kg (0.97 Ib) CC>2 per kg lime. The
following Table reports the final CC>2 emission factor in terms of emissions per kg masonry
cement produced.
Table 3.24: Emissions from Masonry_
. . „ . . Emission Factor
Air Emission , ,, „
per kg Masonry Cement
Carbon Dioxide (CO2) a0209kg(a046llb)
Portland Cement Production. BEES documentation on the production of portland cement can
be found under Generic Portland Cement Concrete Products.
Transportation. A small percentage of the above raw materials, assumed to be 10 %, may be
transported more than 3219 km (2 000 mi). When this is the case, transport is assumed to be by
rail. Otherwise, transport is assumed to be an average of 322 km (200 mi), by truck.
Manufacturing
Stucco is "manufactured" at the point of use of the material. See the section below on
"Installation."
Transportation
The stucco raw materials are transported to the building site via diesel truck. The distance
transported is a variable in the BEES model.
Installation
Stucco is assumed to be mixed in a 5.9 kW (8 hp), gasoline powered mixer with a stucco flow
rate of 0.25 m3/h (9 ft3/h), running for 5 min. The stucco is applied manually to the building, so
no energy or environmental impacts are assumed at this installation step. A small amount of
waste, approximately 1 %, is assumed to be generated during the installation process.
A lath made of 100 % recycled steel may be used as a surface for the applied stucco. The amount
of steel used per surface area of stucco applied varies according to application. Lath is used on
wood and metal frame walls; typically 0.15 kg (1/3 Ib) is used per ft2 of wall area.
80
-------
While sheathing, weather resistive barriers, and other ancillary materials may be required to
complete the exterior wall system, these materials are not included in the system boundaries for
BEES exterior wall finishes.
Use
With general maintenance, a properly installed stucco exterior will have a useful life of 100
years. Maintenance will vary greatly with weather conditions, but is usually minimal. Crack
repairs are done manually. Maintenance is not included within the boundaries of the BEES
model.
It is important to consider thermal performance differences when assessing environmental and
economic performance for exterior wall finish product alternatives. Thermal performance affects
building heating and cooling loads, which in turn affect energy-related LCA inventory flows and
building energy costs over the BEES 50-year use stage.
For exterior wall finishes, thermal performance differences are optionally assessed for 14 U.S.
cities spread across a wide range of climate and fuel cost zones, and for electricity, distillate oil,
and natural gas heating fuel types (electricity is assumed for all cooling). When selecting wall
finish alternatives for analysis, if the BEES user chooses to account for thermal performance, he
or she selects the U.S. city closest to the building location and the building heating fuel type, so
that thermal performance differences may be customized to these important contributors to
building energy use.
Three BEES exterior wall finish products affect thermal performance: generic brick and mortar,
Dryvit Outsulation, and Dryvit Outsulation Plus. Assuming a thermal resistance value of R-13 is
required by code for exterior walls, then R-13 insulation on a brick and mortar wall will increase
its thermal performance to about R-15, and on a Dryvit Outsulation or Dryvit Outsulation Plus
wall, to about R-19. If the BEES user chooses to account for thermal performance, use energy
savings for these three products, over and above that provided by R-13 insulation, are accounted
for in the BEES results.84
End of Life
Approximately one-third of U.S. stucco production is used in commercial projects, typically over
masonry or steel studs. At end of life, it is assumed that stucco and lath installed on commercial
buildings in urban areas are recycled. No data are available on recycling of stucco or lath from
residential applications; it is assumed that none of this residential material is recycled.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0LCA Software. 2005. The Netherlands.
84 Note that if generic brick and mortar and/or the two Dryvit products are the only alternatives being compared,
use energy savings are computed relative to the selected alternative with the lowest R-value.
81
-------
U.S. Environmental Protection Agency, "Cement Manufacture (IPCC Source Category 2A1),"
Chapter 4.2, Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2004.
(Washington, DC: U.S. Environmental Protection Agency, April 2006). pp. 4-8 to 4-9
Industry Contacts
Martha VanGeem, P.E. Construction Technology Laboratory, Inc., on behalf of the Portland
Cement Association (August-October 2005)
Medgar Marceau, P.E., Construction Technology Laboratory, Inc., on behalf of the Portland
Cement Association (August-October 2005)
3.4.3 Generic Aluminum Siding
Aluminum siding is a commonly-used exterior wall cladding that is known for its light weight
and durability. Aluminum siding typically has an exterior coating to provide color and durability.
Popular coatings include acrylic, polyester, and vinyl.
For the BEES system, the functional unit is one ft2 of exterior wall area covered with horizontal
aluminum siding in a thickness of 0.061 cm (0.024 in) and a width of 20 cm (8 in). The
aluminum siding is assumed to be fastened with aluminum nails 41 cm (16 in) on center,
requiring approximately 0.000374 kg (0.000825 Ib) of aluminum nails per ft2 The detailed
environmental performance data for this product may be viewed by opening the file
B2011C.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
82
-------
Aluminum Siding
Functional Unit of
Aluminum Siding
Raw Material
Transport
Process
Energy
Figure 3.10: Aluminum Siding System Boundaries
Raw Materials
There are a number of aluminum siding products on the market, most of which are manufactured
using different combinations of aluminum alloys and coating materials. Coating formulations are
generally proprietary; the product studied for the BEES system is manufactured as an aluminum
sheet with a polyvinyl chloride (PVC) thermoset topcoat.
The following Table presents the major constituents of aluminum siding. Life cycle data for the
production of these raw materials comes from the U.S. LCI Database.
Constituent Mass Mass Fraction (%)
ks/nfflb/ff)
Aluminum Alloy Sheet
1.631 (0.3340)
99
1
The aluminum sheet is manufactured from aluminum ingots. Since aluminum recycling is
considered to be a closed loop process and aluminum siding is generally recycled at the end of
the life of the building (see End of Life below), the environmental burdens from aluminum
production are determined by the end-of-life recovery rate and the yield of metal from the
aluminum recycling process. According to The Aluminum Association, 30 % of all aluminum
used in construction is from secondary sources. Therefore, the BEES model assumes a mix of
30 % secondary and 70 % primary aluminum.
83
-------
The vinyl topcoat is 0.08 mm to 0.09 mm (3.3 mils to 3.7 mils) thick; environmental burdens
from the production of PVC come from the SimaPro database.
According to The Aluminum Association, the following aluminum alloys account for over 90
percent of aluminum used in siding: 3005, Alclad 3004, 3003, 1100, and 3105. Their
composition is given in the Table below.
Table 3.26: Alloy Composition1*
Alloy
1100
3003
3004
3005
3105
Average
3000 series only
6061 (nails)
Al
99.0
97.3
96.2
96.3
96.6
97.1
96.6
96.7
Co
-
-
-
0.1
0.2
0.1
0.1
0.2
Fe
0.1
0.1
0.3
0.3
0.3
0.2
0.2
0.3
Pb
-
0.7
0.7
0.7
0.7
0.6
0.7
0.7
Mn
-
-
1.0
0.4
0.5
0.4
0.5
1.0
Mo
0.1
1.2
1.2
1.2
0.6
0.9
1.1
0.2
S
1.0
0.6
0.3
0.6
0.6
0.6
0.5
0.6
Ti
-
-
-
0.1
0.1
0.0
0.1
0.2
Zn
0.0
0.1
0.3
0.3
0.4
0.2
0.3
0.3
Total
100.1
100.0
99.9
100.0
100.0
100.0
100.0
100.0
In all, alloys only account for 2.9 % to 3.3 % of the mass of the aluminum product. The life
cycle environmental data for the alloying metals is not included in the model due to lack of
available data; as a result the model assumes that the alloy is in fact made of 100 % aluminum.
Manufacturing
Energy Requirements and Emissions. Energy requirements and emissions for production of the
individual siding components (rolled aluminum alloy and PVC resin) are included in the BEES
data for the raw material acquisition life-cycle stage. The model, however, does not include the
energy demands or emissions associated with application of PVC topcoat to the aluminum
siding.
In the U.S., approximately half of rolled aluminum products are either hot or cold rolled.86 The
energy requirements for the average of the hot and cold rolling processes are presented in the
Table below.
85 Alloy composition data from http://www.capitolcamco.com/MSDS/MSDS_I_Aluminum.htm.
86BCS, Inc., U.S. Requirements for Aluminum Production: Historical Prospective, Theoretical Limits, and New
Opportunities (Washington, DC: Prepared for the U.S. Department of Energy, Energy Efficiency and Renewable
Energy, February 2003).
84
-------
Diesel 0.00148 (0.636)
Kerosene 0.000131(0.0565)
Gasoline 0.0372 (16.0)
Natural Gas 1.11(479)
Propane 0.00345(1.48)
Electricity 1.11(475)
Total 2.26_(972)_
Transportation. Transportation of rolled aluminum and PVC resin to aluminum siding mills is
assumed to be 402 km (250 mi) by truck.
Waste. Before rolled aluminum sheet is coiled and shipped, edge trimming knives remove
damaged material from the edge of the sheet. The average edge trim loss for hot and cold rolling
is 17 % of unrolled aluminum.87 Edge trim waste is returned to the cast shop for remelting.
Transportation
Transportation of manufactured aluminum siding by heavy-duty truck to the building site is
modeled as a variable of the BEES system.
Installation
Aluminum siding installation is predominately a manual process—a small amount of energy may
be required to operate compressors to power air guns, but this is assumed to be very small and is
not included in the analysis. Installation waste with a mass fraction of 5 % is assumed, and all
waste is assumed to go to landfill.
Nails are assumed to be placed 41 cm (16 in) on center; however, as it is increasingly common to
find buildings with studs 61 cm (24 in) on center, manufacturers are typically providing
instructions for nail spacing of 61 cm (24 in) in order for the fasteners to penetrate this framing
configuration. For installation on 41 cm (16 in) centers, 0.00085 Ib of aluminum nails are used
per ft2 of siding. The overall installation average is still probably close to 41 cm (16 in), but a
slight reduction in the mass of the nails, taken conservatively to be 3 %, is modeled to account
for some installation on 61 cm (24 in) framing.
While sheathing, weather resistive barriers, and other ancillary materials may be required to
complete the exterior wall system, these materials are not included in the system boundaries for
BEES exterior wall finishes.
87 BCS, Inc. U.S. Requirements for Aluminum Production: Historical Prospective, Theoretical Limits, and New
Opportunities.
85
-------
Use
The product is assumed to have a useful life of 80 years. In some instances, siding without
significant corrosion damage can be found after 100 years. However, owners may replace siding
for reasons other than corrosion (e.g., to update the home's exterior appearance or change the
color). It is assumed for the model that the siding remains in place over the 50- year use period.
Buildings with aluminum siding are periodically cleaned, usually for aesthetic reasons.
Information on typical cleaning practices (e.g., frequency of cleaning, types and quantities of
cleaning solutions used) is not available; no use phase impacts from cleaning are included.
It is important to consider thermal performance differences when assessing environmental and
economic performance for exterior wall finish product alternatives. Thermal performance affects
building heating and cooling loads, which in turn affect energy-related LCA inventory flows and
building energy costs over the BEES 50-year use stage.
For exterior wall finishes, thermal performance differences are optionally assessed for 14 U.S.
cities spread across a wide range of climate and fuel cost zones, and for electricity, distillate oil,
and natural gas heating fuel types (electricity is assumed for all cooling). When selecting wall
finish alternatives for analysis, if the BEES user chooses to account for thermal performance, he
or she selects the U.S. city closest to the building location and the building heating fuel type, so
that thermal performance differences may be customized to these important contributors to
building energy use.
Three BEES exterior wall finish products affect thermal performance: generic brick and mortar,
Dryvit Outsulation, and Dryvit Outsulation Plus. Assuming a thermal resistance value of R-13 is
required by code for exterior walls, then R-13 insulation on a brick and mortar wall will increase
its thermal performance to about R-15, and on a Dryvit Outsulation or Dryvit Outsulation Plus
wall, to about R-19. If the BEES user chooses to account for thermal performance, use energy
savings for these three products, over and above that provided by R-13 insulation, are accounted
for in the BEES results.88
End of Life
Aluminum scrap has a significant economic value - the market price of clean, thick-walled scrap
is close to the market price of primary materials. There is therefore a financial incentive to
recover aluminum siding from a building at the end of its useful life.
An EPA report, Characterization of Building-Related Construction and Demolition Debris in the
United States, confirms that the materials most frequently recovered and recycled from
construction and demolition (C&D) debris are concrete, asphalt, metals, and wood. The EPA
study also estimates that from 1 % to 5 % of C&D waste consists of metals. Therefore, the
model assumes that all of the aluminum siding is recovered at the end of its useful life and
returned to a secondary aluminum smelter for recovery.
Note that if generic brick and mortar and/or the two Dryvit products are the only alternatives being compared,
use energy savings are computed relative to the selected alternative with the lowest R-value.
86
-------
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Aluminum Association, Life Cycle Inventory Report for the North American Aluminum
Industry (Washington, DC: Aluminum Association November 1998).
Franklin Associates, " Management of Construction and Demolition Debris in the United
States", Chapter 8, EPA530-R-98-010 - Characterization of Building-Related Construction
and Demolition Debris in the United States (Washington, DC: U.S. Environmental
Protection Agency, June 1998) Found at: http://www.epa.gov/epaoswer/hazwaste/sqg/c&d-
rpt.pdf.
BCS, Inc., U.S. Requirements for Aluminum Production: Historical Prospective, Theoretical
Limits, and New Opportunities (Washington, DC: Prepared for the U.S. Department of
Energy, Energy Efficiency and Renewable Energy, February 2003)
http://www.eere.energv.gov/industry/aluminum/pdfs/al theoretical.pdf.
Industry Contacts
Paola Kistler, Director Environment, EHS FIRST, Alcan Inc. (September 2005)
Michael Skillingberg, The Aluminum Association, Inc. (January 2006)
3.4.4 Generic Cedar Siding
Cedar wood is used for exterior siding because it is a lightweight, low-density, aesthetically-
pleasing material that provides adequate weatherproofing. As with most wood products, cedar
siding production consists of three major steps. First, roundwood is harvested from logging
camps. Second, logs are sent to sawmills and planing mills where the logs are washed, debarked,
and sawed into planks. The planks are edged, trimmed, and dried in a kiln. The dried planks are
then planed and the lumber sent to a final trimming operation. Finally, the lumber from the
sawmill is shaped into fabricated, milled wood products.
For the BEES system, beveled cedar siding 1.3 cm (!/2 in) thick and 15 cm (6 in) wide is studied.
Cedar siding is assumed to be installed with galvanized nails 41 cm (16 in) on center and
finished with one coat of primer and two coats of stain. Stain is reapplied every 10 years.
The detailed environmental performance data for this product may be viewed by opening the file
B2011D.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
87
-------
Cedar Siding
Figure 3.11: Cedar Siding System Boundaries
Raw Materials
CORRIM lumber production data was used to model cedar wood production. This dataset
includes environmental burdens from growing and harvesting softwood logs for forest
management in the Pacific Northwest.89
The growing and harvesting of wood is modeled as a composite comprised of a mix of low-,
medium-, and high-intensity managed timber. Energy use for wood production includes
electricity for greenhouses to grow seedlings, gasoline for chain saws, diesel fuel for harvesting
mechanical equipment, and a small amount of fertilizer. Emissions associated with production
and combustion of gasoline and diesel fuel and those from the production and delivery of
electricity are based on the U.S. LCI Database. Fertilizer production data is adapted from
European data in the U.S. LCI Database. Electricity use for greenhouse operation is based on
the grids for the region where the seedlings are grown, while the U.S. average electricity grid is
used for fertilizer production. The weight of wood harvested for lumber is based on an average
oven-dry density of 509.77 kg/m3 (31.824 Ib/ft3).
BEES modeling accounts for the absorption of carbon dioxide by trees as they grow; the carbon
becomes part of the wood, and the oxygen is released to the atmosphere. The "uptake" of carbon
dioxide from the atmosphere during the growth of timber is about 1.84 kg (4.06 Ib) of carbon
dioxide per kilogram of harvested wood (oven-dry weight).
Bowyer, J., et. al., Phase I Final Report: Life Cycle Environmental Performance of Renewable Building
Materials in the Context of Residential Construction. (Seattle, WA: Consortium for Research on Renewable
Industrial Materials-CORRIM, Inc./University of Washington, 2004). Found at:
http://www.corrim.org/reports600+ pp.; data also submitted to US LCI Database.
-------
Manufacturing
Energy Requirements and Emissions. The energy requirements allocated to the production of
softwood lumber for cedar siding are listed in the Table below. These requirements are based on
average manufacturing conditions in the U.S. Pacific Northwest (PNW). The energy comes
primarily from burning wood and bark waste generated in the sawmill process. Other fuel
sources include natural gas for boilers, and propane and diesel for forklifts and log haulers at the
sawmill. The production and combustion of the different types of fuel are based on the U.S. LCI
Database.
Table 3.28: Cedar Siding Production Energy
Quantity
Energy Carrier per Ib
Cedar Siding
Electricity - PNW Grid 4.68E+05 J (0.13 kWh)
Natural Gas 4.53E-03 m3 (0.16 ft3)
Diesel fuel 2.01E-03 L (5.3E-04 gal)
LPG 1.21E-03 L (3.2E-04 gal)
Hogfuel/Biomass 1.90E-01 kg (0.42 Ib)
Allocated process-specific air emissions from lumber production are based on the CORRIM
study, as reported in the Table below. Allocation is based on mass and a multi-unit process
analysis to correctly assign burdens. Note: In the BEES model, CO2 generated by combustion of
biofuel (hogged wood fuel) and fossil fuel are tracked separately since CC>2 from biomass is
considered environmentally impact-neutral by the U.S. EPA, and as such is not considered when
determining the Global Warming Potential impact.
Table 3.29: Cedar Siding Production Process-RelatedKmissions
Air Emission Emissions per Ib
Cedar_Siding
Particulates (unspecified) 1.36E-05 kg (3.OE-05 Ib)
VOC (unspecified) 8.62E-05 kg (1.9E-04 Ib)
Transportation. Since sawmills are typically located close to the forested area, transportation of
raw materials to the sawmill is not taken into account. Transport of primer and stain to the
manufacturing plant is included.
Transportation
Transportation of cedar siding by heavy-duty truck to the building site is modeled as a variable
of the BEES system.
Installation
Cedar siding installation is predominately a manual process—a relatively tiny amount of energy
may be required to operate compressors to power air guns, but this amount is assumed to be too
89
-------
small to warrant inclusion in the analysis. Installation waste with a mass fraction of 5 % is
assumed, and all waste is assumed to go to landfill.
Cedar siding panels are attached using galvanized nails. Three nails are required per 0.09 m2
(per ft2) of siding. Assuming standard 6d 5 cm (2 in) nails, installation requires 0.0054 kg
(0.0119 Ib) of nails per ft2 of siding. No installation waste is assumed for the nails.
After installation, the siding is primed and stained. The primer is modeled as a standard primer
with coverage of 46.4 m2 (500 ft2) per gal; the stain is assumed to have coverage of 32.5 m2 (350
ft2) per gal. One coat of primer and two coats of stain are applied to the siding.
While sheathing, weather resistive barriers, and other ancillary materials may be required to
complete the exterior wall system, these materials are not included in the system boundaries for
BEES exterior wall finishes.
Use
The density of cedar siding at 12 % moisture content is assumed to be 449 kg/m3 (28 Ib/ft3). The
product is assumed to have a useful life of 40 years. To prolong the lifetime and maintain the
appearance of the siding, two coats of stain are assumed to applied every 10 years. Information
on typical cleaning practices (e.g., frequency of cleaning, types and quantities of cleaning
solutions used) is not available; cleaning is not included in the system boundaries.
It is important to consider thermal performance differences when assessing environmental and
economic performance for exterior wall finish product alternatives. Thermal performance affects
building heating and cooling loads, which in turn affect energy-related LCA inventory flows and
building energy costs over the BEES 50-year use stage.
For exterior wall finishes, thermal performance differences are optionally assessed for 14 U.S.
cities spread across a wide range of climate and fuel cost zones, and for electricity, distillate oil,
and natural gas heating fuel types (electricity is assumed for all cooling). When selecting wall
finish alternatives for analysis, if the BEES user chooses to account for thermal performance, he
or she selects the U.S. city closest to the building location and the building heating fuel type, so
that thermal performance differences may be customized to these important contributors to
building energy use.
Three BEES exterior wall finish products affect thermal performance: generic brick and mortar,
Dryvit Outsulation, and Dryvit Outsulation Plus. Assuming a thermal resistance value of R-13 is
required by code for exterior walls, then R-13 insulation on a brick and mortar wall will increase
its thermal performance to about R-15, and on a Dryvit Outsulation or Dryvit Outsulation Plus
wall, to about R-19. If the BEES user chooses to account for thermal performance, use energy
savings for these three products, over and above that provided by R-13 insulation, are accounted
for in the BEES results.90
90 Note that if generic brick and mortar and/or the two Dryvit products are the only alternatives being compared,
use energy savings are computed relative to the selected alternative with the lowest R-value.
90
-------
End of Life
All of the cedar siding is assumed to be disposed of in landfill at end of life. The practice of
recycling wood building materials is increasing, but data is not available to quantify this
practice.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0LCA Software. 2005. The Netherlands.
Bowyer, J., et. al., Phase I Final Report: Life Cycle Environmental Performance of Renewable
Building Materials in the Context of Residential Construction. (Seattle, WA: Consortium for
Research on Renewable Industrial Materials. (CORRIM, Inc.)/University of Washington,
2004). Found at: http://www.corrim.org/reports.
Industry Contacts
No industry contacts were identified to provide further insight on this product.
3.4.5 Generic Vinyl Siding
Vinyl siding is used as an exterior wall finish on new and renovated construction. Since its
introduction in the 1960s, vinyl siding has become the most popular wall finish for new
construction.
The product is manufactured in a wide variety of profiles, colors, and thicknesses to meet
different market applications. Vinyl siding is commonly produced as double units that have the
appearance of two overlapping or adjoining 10 cm or 13 cm wide (4 in or 5 in wide) boards.
Double 4 and double 5 are the most common profiles and are about equally popular. The weight
of vinyl siding is about 24 kg (52 Ib) per 9.29 m2 (100 ft2), for a typical 0.107 cm to 0.112 cm
(0.042 in to 0.044 in) thickness. For the BEES system, 0.107 cm (0.042 in) thick, 23 cm (9 in)
wide horizontal vinyl siding installed with galvanized nail fasteners is studied. The nails are
assumed to be placed 41 cm (16 in) on center.
The detailed environmental performance data for this product may be viewed by opening the file
B201 IE.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram that follows shows the major elements of the production of this product, as it
is currently modeled for BEES.
91
-------
Vinyl Siding
Functional Unit of
Vinyl Siding
Titanium
Dioxide
Production
Filler
(Calcium
Carbonate)
Impact
Modifier
Titanium
Dioxide
Production
Impact
Modifier
Stabilizer
Lubricant
Figure 3.12: Vinyl Siding System Boundaries
Raw Materials
Most siding is composed of two layers: a substrate and a capstock. The capstock, which accounts
for about 15 % by weight of the full panel, is the surface that is exposed to the outside and thus is
formulated to be more weather resistant.
Polyvinyl chloride (PVC) is the main component in the manufacture of vinyl siding. A
significant percentage of the final product is composed of post-industrial PVC waste (i.e., PVC
cuttings and scraps collected from the manufacturing process and recycled into future batches).
A typical percentage of the final product is 15 % recycled post-industrial material. Calcium
carbonate is used as a filler material in vinyl siding. Titanium dioxide (TiC^) is a chemical
additive that is used in the siding as a pigment and stabilizer; less than 10 % of it is produced
from ore mined in the United States. The ore is produced in diverse locations including Canada,
92
-------
Africa, and Australia. All other components are typically supplied from within 3219 km (2 000
mi) of the siding manufacturing facility.
The Table below presents the proportions of constituent materials in the siding studied. Data
representing the production of raw materials for vinyl siding are based on the SimaPro LCA
database, the U.S. LCI Database, and American Chemistry Council 2006 data developed for
submission to the U.S. LCI Database.
Constituent
PVC
Filler (typically, calcium carbonate)
Titanium dioxide
Impact modifier (typically, acrylic
or chlorinated polyethylene)
Stabilizer (typically, organo-tin
mercaptide)
Lubricant (typically,
paraffin/calcium stearate blend)
Percent in
Substrate
82%
10%
<1.5 %
<4%
1%
1.5%
Percent in
85.5 %
—
8.5 %
3%
1.5%
1.5%
Overall
Percent
82.5 %
8.5 %
2.5 %
4%
1%
1.5%
Manufacturing
Most manufacturers of vinyl siding in North America are located east of the Mississippi, the
exceptions being manufacturers in Missouri and Texas. Most vinyl siding is extruded, although a
small percentage of specialty panels are injection molded or thermoformed. For a general
characterization of vinyl siding, extrusion is most appropriate.
Energy Requirements. Energy requirements for production of the individual siding components
are included in the data for the raw material acquisition life-cycle stage. No information was
available from manufacturers on energy and emissions for the vinyl siding production process.
Transportation. Transportation of siding raw materials from producers to the siding
manufacturing plant is taken into account. An assumed average transport distance of 402 km
(250 mi) is applied to each raw material.
Waste. As noted in the raw materials description for this product, scrap from siding production
processes is typically collected at the plant and recycled back into the manufacturing process.
Transportation
Transportation of the manufactured siding and nails to the building site by heavy-duty truck is
modeled as a variable of the BEES software.
Installation
Installation of siding is done primarily by manual labor. Nails or screws can be used to install the
siding; nails are more common and would typically be the type installed with a gun. The energy
required to operate compressors to power air guns is assumed to be very small and not included
93
-------
in the analysis. Installation waste with a mass fraction of 5 % is assumed, and this waste is
assumed to go to a landfill.
Nails are placed 41 cm (16 in) on center; however, as it is increasingly common to find buildings
with studs 61 cm (24 in) on center, manufacturers are typically providing instructions for nail
spacing of 61 cm (24 in) in order for the fasteners to penetrate this framing configuration. Such
installations represent a small but growing subset of vinyl siding applications. For installation on
41 cm (16 in) centers, nail use is 0.0024 kg (0.0053 Ib) per 0.09 m2 (per ft2) of siding. The
overall installation average is still probably close to 41 cm (16 in), but a slight reduction in the
number of nails per ft2 is modeled to account for the small proportion installed on 61 cm (24 in)
framing.
While sheathing, weather resistive barriers, and other ancillary materials may be required to
complete the exterior wall system, these materials are not included in the system boundaries for
BEES exterior wall finishes.
Use
The product is assumed to have a useful life of 40 years. Many manufacturers provide warranties
of 50 years or longer. No routine maintenance is required to prolong the lifetime of the product,
although cleaning is recommended to maintain appearance. Cleaning would normally be done
with water and household cleaners. Information on typical cleaning practices (e.g., frequency of
cleaning, types and quantities of cleaning solutions used) was not available; maintenance was not
included in the system boundaries.
It is important to consider thermal performance differences when assessing environmental and
economic performance for exterior wall finish product alternatives. Thermal performance affects
building heating and cooling loads, which in turn affect energy-related LCA inventory flows and
building energy costs over the BEES 50-year use stage.
For exterior wall finishes, thermal performance differences are optionally assessed for 14 U.S.
cities spread across a wide range of climate and fuel cost zones, and for electricity, distillate oil,
and natural gas heating fuel types (electricity is assumed for all cooling). When selecting wall
finish alternatives for analysis, if the BEES user chooses to account for thermal performance, he
or she selects the U.S. city closest to the building location and the building heating fuel type, so
that thermal performance differences may be customized to these important contributors to
building energy use.
Three BEES exterior wall finish products affect thermal performance: generic brick and mortar,
Dryvit Outsulation, and Dryvit Outsulation Plus. Assuming a thermal resistance value of R-13 is
required by code for exterior walls, then R-13 insulation on a brick and mortar wall will increase
its thermal performance to about R-15, and on a Dryvit Outsulation or Dryvit Outsulation Plus
wall, to about R-19. If the BEES user chooses to account for thermal performance, use energy
savings for these three products, over and above that provided by R-13 insulation, are accounted
94
-------
for in the BEES results.91
End of Life
Vinyl siding at end of life is assumed to be disposed of in a landfill. End-of-life quantities of
vinyl siding have not been large enough to warrant establishment of a recycling infrastructure.
Vinyl siding is not among the top 36 building-related construction and demolition categories
reported in the U.S. Environmental Protection Agency (EPA) benchmark report on construction
and demolition waste.92
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0LCA Software. 2005. The Netherlands.
Franklin Associates, " Management of Construction and Demolition Debris in the United
States", Chapter 8, EPA530-R-98-010 - Characterization of Building-Related Construction
and Demolition Debris in the United States (Washington, DC: U.S. Environmental
Protection Agency, June 1998) Found at: http://www.epa.gov/epaoswer/hazwaste/sqg/c&d-
rpt.pdf.
Industry Contacts
David Johnston, Technical Director, Vinyl Siding Institute (September-October 2005)
3.4.6 Trespa Meteon Panel
See documentation on all Trespa composite panels under Fabricated Toilet Partitions.
3.4.7 Headwaters Stucco Finish Application
Headquartered in Salt Lake City, Utah, Headwaters, Inc. is a supplier of materials to products as
diverse as ready-mix concrete, precast concrete, roofing, carpeting, mortar, and stucco. Three
Headwaters products are included in BEES
• Masonry Cement Type S. Meets ASTM C91 Type S standard for masonry cement.
• Scratch & Brown Stucco Cement. Meets ASTM C1328 Type S standard for plastic (stucco)
cement. Used as a replacement for job-site-mixed stuccos (usually portland and lime or
Portland and masonry cement) under ASTM C926.
• FRS. Produced and sold under ICBO Evaluation Report No. 4776 and ICC Legacy
Evaluation Report 459. At this time there are no ASTM standards for this class of products.
91 Note that if generic brick and mortar and/or the two Dryvit products are the only alternatives being compared,
use energy savings are computed relative to the selected alternative with the lowest R-value.
92 Franklin Associates, " Management of Construction and Demolition Debris in the United States", Chapter 8,
EPA530-R-98-010 - Characterization of Building-Related Construction and Demolition Debris in the United States
(Washington, DC: US Environmental Protection Agency, June 1998) Found at:
http://www.epa.gov/epaoswer/hazwaste/sqg/c&d-rpt.pdf.
95
-------
BEES data for these products are based on 2005 data from the manufacturer's San Antonio,
Texas plant, with an annual production of 27 945 metric tons (30 804 short tons). These
cementitious products are incorporated in different stucco finishes in BEES as shown in the
Table below:
Table 3.31: Headwaters Cement Products
BEES Exterior Wall Headwaters
Product
Masonry
Cement Type S
Headwaters Masonry
Cement Type S-based
Stucco
Headwaters Scratch
& Brown Stucco
Cement Type S
Scratch &
Brown Stucco
Cement Type S
Headwaters FRS-
based Stucco
FRS
Specifications
1 kg (2.2 Ib) of Masonry Cement
Type S produced by Headwaters
replaces 1 kg (2.2 Ib) of traditional
Masonry Cement Type S used in
generic stucco. Fully 100 % of the
traditional cement is replaced by
Headwaters' Masonry Cement.
1 kg (2.2 Ib) of Scratch & Brown
Stucco Cement Type S produced by
Headwaters replaces 1 kg (2.2 Ib) of
traditional Masonry Cement Type S
used in generic stucco. Fully 100 %
of the traditional cement is replaced
by Headwaters' Scratch and Brown
Stucco Cement.
1 kg (2.2 Ib) of FRS produced by
Headwaters replaces 2 kg (4.4 Ib) of
traditional Masonry Cement. Fully
100 % of the traditional cement is
replaced by Headwaters' FRS. The
metallic lath weighs either
0.95 kg/m2 (1.75 lb/yd2) or 1.36
kg/m2 (2.50 lb/yd2). The lighter-
weight lath is used in 60 % of the
applications.
The detailed environmental performance data for these products may be viewed by opening the
following files under the File/Open menu item in the BEES software:
• B2011H.DBF—Headwaters Scratch & Brown Stucco Cement Type S
• B2011I.DBF—Headwaters FRS-based Stucco
• B2011K.DBF—Headwaters Masonry Cement Type S-based Stucco
Flow Diagram
The flow diagram shown below shows the major elements of the production of this product, as it
is currently modeled for BEES.
96
-------
Headwaters, Inc. Cement Products
Coarse
Aggregate
Production
Headwaters
Products
Production
Portland
Cement
Production
Lime
Production
Figure 3.13: Headwaters Cement Products System Boundaries
Raw Materials
The three Headwaters products are comprised of the raw materials given in the Table below.
Table 3.32: Headwaters Cement Constituents
Constituent
Masonry Scratch &
Cement Brown Stucco
Tyjie_S_ Cement
FRS
Fly Ash (class F)
Portland Cement (gray,
type I)
Hydrated Lime (type S)
Yes
Yes
Yes
No
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
97
-------
Portland cement. The BEES generic portland cement data are used for the portland cement
constituent, and comes from the Portland Cement Association LCA database, which is
documented under Generic Portland Cement Concrete Products.
Fly Ash. Fly ash comes from coal-fired, electricity-generating power plants. These power plants
grind coal to a fine powder before it is burned. Fly ash - the mineral residue produced by
burning coal - is captured from the power plant's exhaust gases and collected for use. Fly ash
particles are nearly spherical in shape, allowing them to flow and blend freely in mixtures, one of
the properties making fly ash a desirable admixture for concrete. In LCA terms, this waste
byproduct from coal combustion is assumed to be an environmentally "free" input material.93
Transport of the fly ash from the production site is included in the product modeling.
Lime and Polypropylene. Data for hydrated lime production takes into account limestone
extraction, crushing and calcination, and quick lime hydration, and comes from the U.S. LCI
Database. Data for polypropylene production comes from the U.S. LCI Database.
Manufacturing
Energy Requirements and Emissions. Raw materials are brought to the cement plant in 18-
wheel tankers and blown into silos. Material drops from the silos to a weigh-batcher, a blender,
and a bagger. Only one product is produced at a time for at least a full day. Since all gray (fly
ash-containing) products are related, changing products consists of tapping the system down and
bagging the last of the product in the system. Allocation of the resources is based on the number
of bags of each product produced. Energy consumed on site is mostly electricity (87 %) and
diesel fuel oil. The site produces solid waste (1 % of production) and emits particulates. All
energy and electricity data is based on the U.S. LCI Database.
Transportation. The transportation distance of raw materials from the supplier to the
manufacturer was provided by Headwaters and ranges from 16 km (10 mi) for the polypropylene
fibers, to 48 km (30 mi) for the portland cement and lime, to 660 km (410 mi) for the fly ash.
Materials are transported by diesel truck, with burdens modeled using the U.S. LCI Database.
Transportation
Transportation of finished products to the building site is evaluated based on the same
parameters given for the generic counterparts to Headwaters' products, and all products are
shipped by diesel truck. Emissions from transportation allocated to each product depend on the
overall weight of the product. Diesel truck transportation is based on the U.S. LCI Database.
Installation and Use
While sheathing, weather resistive barriers, and other ancillary materials may be required to
complete the exterior wall system, these materials are not included in the system boundaries for
BEES exterior wall finishes. Maintenance for Headwaters' exterior stucco products will vary
depending on weather conditions, but usually consists of minimal repairs that can be done by
hand. Maintenance is not included in the system boundaries for this product.
93 The environmental burdens associated with the production of waste materials are typically allocated to the
intended product(s) of the process from which the waste results.
98
-------
It is important to consider thermal performance differences when assessing environmental and
economic performance for exterior wall finish product alternatives. Thermal performance affects
building heating and cooling loads, which in turn affect energy-related LCA inventory flows and
building energy costs over the BEES 50-year use stage.
For exterior wall finishes, thermal performance differences are optionally assessed for 14 U.S.
cities spread across a wide range of climate and fuel cost zones, and for electricity, distillate oil,
and natural gas heating fuel types (electricity is assumed for all cooling). When selecting wall
finish alternatives for analysis, if the BEES user chooses to account for thermal performance, he
or she selects the U.S. city closest to the building location and the building heating fuel type, so
that thermal performance differences may be customized to these important contributors to
building energy use.
Three BEES exterior wall finish products affect thermal performance: generic brick and mortar,
Dryvit Outsulation, and Dryvit Outsulation Plus. Assuming a thermal resistance value of R-13 is
required by code for exterior walls, then R-13 insulation on a brick and mortar wall will increase
its thermal performance to about R-15, and on a Dryvit Outsulation or Dryvit Outsulation Plus
wall, to about R-19. If the BEES user chooses to account for thermal performance, use energy
savings for these three products, over and above that provided by R-13 insulation, are accounted
for in the BEES results.94
End of Life
With general maintenance, exterior stucco wall finishes will generally last more than 100 years.
This is a performance-based lifetime.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Industry Reference
Herb Nordmeyer, Headwaters, Inc. (2006)
3.4.8 Dryvit EIFS Cladding Outsulation
In 1969, Dryvit Systems, Inc., currently owned by RPM International Inc. in Medina, OH,
introduced North America to its exterior wall cladding system with insulation installed as part of
the outside wall. Since that time, Dryvit's Exterior Insulation and Finish Systems (EIFS) have
been used on commercial and residential buildings in the United States.
The two most widely used EIFS cladding, Outsulation and Outsulation Plus, are evaluated in
94 Note that if generic brick and mortar and/or the two Dryvit products are the only alternatives being compared,
use energy savings are computed relative to the selected alternative with the lowest R-value.
99
-------
BEES. These are comprised of an expanded polystyrene (EPS) insulation board, a fiberglass
mesh which is used for reinforcement, a polymer modified cement-based adhesive/basecoat and
a polymer-based textured finish used as a top coat to enhance aesthetic appeal. Outsulation Plus
is a next generation cladding that has an added layer of air and moisture barrier which not only
protects the wall from accidental moisture but provides better insulation by stopping air
infiltration. Both of these cladding systems can be installed in new and existing buildings.
Dryvit operates four manufacturing plants in the United States, including one at its headquarters
in West Warwick, RI, and has subsidiary operations in Canada, Poland, and China. The data for
the BEES evaluation is based on the West Warwick, RI facility.
Both Outsulation and Outsulation Plus are installed onto sheathing. While they are thermally
efficient, the building still requires insulation. According to the manufacturer, both products
provide a thermal resistance value of about R-6. The BEES user has the option of accounting for
the energy saved, relative to other exterior wall finishes, over the 50-year use period. This is
explained in more detail under Use.
The detailed environmental performance data for this product may be viewed by opening the
files B2011L.DBF, for Dryvit Outsulation, and B2011M.DBF, for Dryvit Outsulation Plus,
under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagrams below shows the major elements of the production of these products as they
are currently modeled for BEES.
100
-------
Dryvit Outsulation
-.. fc Functional Unit of
BldgSite Outsulat on siding
t
t 1
Portland
Cemen
production
Outsulation
production
t
T
Fiberglass
mes
production
t +
1
EP Pr mu Quarzp
production Production Produc
' '
t T
GPP
production
Solvent Acrylic resin Aggregate/
production production sand p
Process
jtz energy
ion ^
Raw mater al
t t
TiO2 Other ma 'Is '
reduction production Water
Figure 3.14: Dryvit Outsulation System Boundaries
Dryvit Outsulation Plus
Portland
Cemen
production
Outsulation
Plus
production
i
L
Backsto
Production
Primus
Production
Quarzputz
Production
Solvent
production
Acrylic resin
production
T T
Aggregate/
sand
Ti02
production
Other ma 'Is
production
Water
Figure 3.15: Dryvit Outsulation Plus System Boundaries
101
-------
Raw Materials
Outsulation's basecoat, the textured finish top coat, and the barrier layer offered as part of
Outsulation Plus are mixed and packaged at Dryvit's facility. These products and their
constituent materials are presented in the Table below.
Table 3.33: Dryvit Product
Constituent
Solvent
Resins
Aggregate
Fine filler
Titanium dioxide slurry
Other materials
Water
Adhesive/Basecoat
(Primus)
yes
yes
yes
yes
yes
Constituents
Topcoat
(Quarzputz)
yes
yes
yes
yes
yes
yes
yes
Barrier
(Backstop
yes
yes
yes
yes
yes
yes
yes
The solvent, considered to be mineral spirits, is modeled as naphtha, whose data comes from the
refining model in a U.S. Department of Agriculture and U.S. Department of Energy study on
biodiesel and petroleum diesel fuels.95 The fine filler is modeled as lime, which is based on the
U.S. LCI Database. The resin is modeled as an acrylic-based resin. Data for this resin, plus the
aggregate and titanium dioxide (TiC^) slurry, are based on elements of the SimaPro database,
which is comprised of a mix of U.S. and European data. Water makes up over 23 % of
Quarzputz and Backstop NT and almost 30 % of Primus.
Primus is just one of Dryvit's products that can be used as a basecoat and adhesive in
Outsulation. Dryvit's other wet and dry basecoats include Genesis, Primus DM, and Genesis
DM. Dryvit also produces a variety of textured finishes. The most popular are Quarzputz,
Sandblast, Sandpebble and Sandpebble Fine. These are available in three bases (Mid base,
Pastel base, and Accent base) depending upon the amount of TiO2 present. The bases can be
tinted to the desired color either in the factory or at distributor locations.
The packaging of these products (5 gal polypropylene pails) is included in the model, with the
polypropylene data coming from American Chemistry Council 2006 data developed for
submission to the U.S. LCI Database.
Manufacturing
Energy Requirements and Emissions. Energy use at the Dryvit plant is primarily electricity to
blend the Primus, Quarzputz, and Backstop NT constituents in large vessels and package them
into 5 gal pails. The quantity of electricity used for each product is provided in the Table below.
95 Sheehan, J. et al, Life Cycle Inventory of Biodiesel and Petroleum Diesel for Use in an Urban Bus, NREL/SR-
580-24089 (Washington, DC: US Department of Agriculture and US Department of Energy, May 1998).
102
-------
Table 3.34: Energy Requirements for Mixing Dryvit Outsulation and Outsulation Plus
kWMb
Primus 6.26 E-4
Quarzputz 1.28E-3
Backstop NT 7.47 E-4
Electricity production fuels and burdens come from the U.S. LCI Database. Any fine material
particulates released during blending is captured by a dust collection system, so no particulates
or other emissions are released. No manufacturing waste is produced.
Transportation. Transportation distances of the product components were provided by Dryvit
and range from 1 770 km (1 100 mi) for the fillers and 1 086 km (675 mi) for the aggregate,
down to 80 km (50 mi) for the solvent. These are transported by diesel truck, as modeled in the
U.S. LCI Database.
Transportation
Dryvit products, plus the EPS and fiberglass mesh (neither of which are produced by Dryvit), are
modeled, by default, as being transported an average of 402 km (250 mi) by diesel truck to the
building site. The BEES user is free to change this assumed transport distance.
Installation
Dryvit' s components described above, plus the EPS and fiberglass mesh, are installed together at
the building site to produce the Outsulation and Outsulation Plus products. These materials are
specified in the following two tables. Note that while sheathing, weather resistive barriers, and
other ancillary materials are required to complete the exterior wall system, these materials are
not included in the system boundaries for BEES exterior wall finishes.
Constituent Specification Quantity per 9 m2
EPS 2 ft x 4 ft x 1.5 in 5.67 kg (12.5 Ib)
2
Fiberglass Mesh 4.3 oz/yd 1.35 kg (2.98 Ib)
Primus 5 gal pail = 60 Ib = 1 10 ft2 25 kg (55 Ib)
103
-------
^
Constituent Specification Quantity per 9 m2
EPS 2 ft x 4 ft x 1.5 in 5.67 kg (12.5 Ib)
2
Fiberglass Mesh 4.3 oz/yd 1.35 kg (2.98 Ib)
Primus 5 gal pail = 60 Ib = 1 10 ft2 25 kg (55 Ib)
2
Quarzputz 5 gal pail = 70 Ib = 130 ft 24.43 kg (53.85 Ib)
ackstorj^TTexture .............. 5 gal j^^ [[[ 9J9___k£__(2L8]b)
EPS is produced by licensed EPS molders to a specification that has been established by Dryvit
and ASTM. Fiberglass mesh also is produced to Dryvit specification and ASTM standard. The
Dryvit basecoats, weather barriers, and finishes are used on the jobsite by trained plasterers. The
process of applying EIFS Cladding begins once the stud walls are constructed and sheathing is
up. (For consistency with other exterior wall finish products, sheathing is not included in the
product model.) The EPS is applied to the sheathing with Primus as the adhesive and then again
coated with Primus for a basecoat. In the field, Primus is mixed with equal amounts of cement.
The fiberglass mesh is embedded into the basecoat. After 24 h of drying time, the textured
finish, Quarzputz, is placed as the top coat. Outsulation Plus installation includes a layer of
Backstop NT for the added layer of air and moisture barrier.
Data for EPS resin production and blowing into foam insulation and fiberglass are based on the
SimaPro database. For the BEES system, these are included with the raw material acquisition
stage data since they are considered part of the main product. Portland cement (mixed with
Primus) is included with the use stage of the product model, and its data comes from the U.S.
LCI Database. For detailed information on this latter material, see Generic Portland Cement
Concrete Products.
According to the manufacturer, installation waste can run from 1 % to 5 %; 2.5 % is modeled for
BEES. This waste is assumed to go to landfill.
Use
Any maintenance or cleaning over the life, if needed, is done manually and with relatively few
materials. Because maintenance can vary from owner to owner based on frequency and degree,
representative data was neither available nor included in the model.
It is important to consider thermal performance differences when assessing environmental and
economic performance for exterior wall finish product alternatives. Thermal performance affects
building heating and cooling loads, which in turn affect energy-related LCA inventory flows and
building energy costs over the BEES 50-year use stage.
For exterior wall finishes, thermal performance differences are optionally assessed for 14 U.S.
cities spread across a wide range of climate and fuel cost zones, and for electricity, distillate oil,
and natural gas heating fuel types (electricity is assumed for all cooling). When selecting wall
finish alternatives for analysis, if the BEES user chooses to account for thermal performance, he
-------
that thermal performance differences may be customized to these important contributors to
building energy use.
Three BEES products affect thermal performance: generic brick and mortar, Dryvit Outsulation,
and Dryvit Outsulation Plus. Assuming a thermal resistance value of R-13 is required by code
for exterior walls, then R-13 insulation on a brick and mortar wall will increase its thermal
performance to about R-15, and on a Dryvit Outsulation or Dryvit Outsulation Plus wall, to
about R-19. If the BEES user chooses to account for thermal performance, use energy savings
for these three products, over and above that provided by R-13 insulation, are accounted for in
the BEES results.96
End of Life
Both Dryvit products are assumed to have useful lives of 50 years. At end of life, it is assumed
that Outsulation and Outsulation Plus materials are waste and sent to a landfill.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 7.0 LCA Software. 2005. The Netherlands.
Sheehan, J. et al., Life Cycle Inventory ofBiodiesel and Petroleum Diesel for Use in an Urban
Bus, NREL/SR-5 80-24089 (Washington, DC: U.S. Department of Agriculture and U.S.
Department of Energy, May 1998).
Industry Contacts
Dr. Chander Patil, Dryvit Systems Inc. (August 2006)
3.5 Insulation
3.5.1 Generic Cellulose
Blown cellulose insulation is produced primarily from post-consumer wood pulp (newspapers),
typically accounting for roughly 85 % of the insulation by weight. Cellulose insulation is treated
with fire retardant. Ammonium sulfate, borates, and boric acid are used most commonly and
account for the other 15 % of the cellulose insulation by weight.
BEES performance data are provided for thermal resistance values of R-13 for a wall application
and R-38 for a ceiling application. The amount of cellulose insulation material used per
functional unit is shown in the following Table, based on information from the Cellulose
Insulation Manufacturers Association (CIMA) and the U.S. Department of Energy.
96 Note that if generic brick and mortar and/or the two Dryvit products are the only alternatives being compared,
use energy savings are computed relative to the selected alternative with the lowest R-value.
105
-------
_Ap_pJicati(m
Wall-R-13
^dling-R-38
Thickness
££^_fe)^_^
8.9(3.5)
27.6(10.9}
Density Mass per Functional Unit
_MnLdM^l M™2....$M?1
35.3 (2.20)
_27.2_(1.70)_
3.13 (0.641)
J7.52_(1.54)_
The detailed environmental performance data for these products may be viewed by opening the
following files under the File/Open menu item in the BEES software:
• B2012A.DBF—Blown Cellulose R-13
• B3012A.DBF—Blown Cellulose R-38
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
Cellulose Insulation Production
Figure 3.16: Cellulose Insulation System Boundaries
Raw Materials
Cellulose insulation is essentially shredded recovered wastepaper that is coated with fire
retardants. The mix of these materials is provided in the following Table; while the relative
proportions of the fire retardants vary among manufacturers, they are assumed to be mixed in
equal proportions for BEES.
106
-------
Table 3.38^_Cellulose Insulation_Constituents_
Constituent^
Recovered Newspaper
Ammonium Sulfate
Boric Acid
BEES recovered newspaper data includes burdens from wastepaper collection, sorting, and
subsequent transportation to the insulation manufacturer. Since it is a recovered product,
burdens from upstream production of the pulp are not included in the system boundaries.
Ammonium sulfate is assumed to be a co-product of the production of nylon (caprolactam). The
boric acid flame retardant is assumed to be produced from borax. Data for both materials,
representing the early 2000s, is European.
Manufacturing
Energy Requirements and Emissions. There are no wastes or water effluents from the process
of manufacturing cellulose insulation. The process includes shredding the wastepaper and
blending it with the different fire retardants. Manufacturing energy is assumed to come from
purchased electricity, as shown below.
Table 3.39:
Energy Carrier
Electricity 0.35 (150)
Transportation. The raw materials are all assumed to be shipped 161 km (100 mi) to the
manufacturing plant via diesel truck.
Waste. All waste produced during the production process is recycled back into other insulation
materials. Therefore, no solid waste is generated during the production process.
Transportation
Transportation of cellulose insulation by heavy-duty truck to the building site is modeled as a
variable of the BEES system.
Installation
Cellulose insulation has a functional lifetime of more than 50 years - there is no need to replace
or maintain the insulation during normal building use. During the installation of loose fill
insulation, any waste material is added into the building shell where the insulation is installed, so
there is effectively no installation waste.
For loose fill insulation, a diesel generator is used to blow the insulation material into the space.
For one h of operation, a typical 18 kW (25 hp) diesel engine can blow 818 kg (1 800 Ib) of
insulation. The emissions and energy use for this generator are included in the system boundaries
for this product. No other installation energy is required.
107
-------
Use
It is important to consider thermal performance differences when assessing environmental and
economic performance for insulation product alternatives. Thermal performance affects building
heating and cooling loads, which in turn affect energy-related LCA inventory flows and building
energy costs over the 50-year use stage. Since alternatives for ceiling insulation all have R-38
thermal resistance values, thermal performance differences are at issue only for the wall
insulation alternatives.
For wall insulation, thermal performance differences are separately assessed for 14 U.S. cities
spread across a wide range of climate and fuel cost zones, and for electricity, distillate oil, and
natural gas heating fuel types (electricity is assumed for all cooling). When selecting wall
insulation alternatives for analysis, the BEES user selects the U.S. city closest to the building
location and the building heating fuel type, so that thermal performance differences may be
customized to these important contributors to building energy use. A NIST study of the
economic efficiency of energy conservation measures (including insulation), tailored to these
cities and fuel types, is used to estimate 50-year heating and cooling requirements per functional
unit of insulation.97 BEES environmental performance results account for the energy-related
inventory flows resulting from these energy requirements. To account for the 50-year energy
requirements in BEES economic performance results, 2005-2006 winter fuel prices by U.S.
region98 and U.S. Department of Energy fuel price projections over the next 30 years99 are used
to compute the present value cost of operational energy per functional unit for each R-value.
End of Life
While cellulose insulation is mostly recyclable, it is assumed that all of the insulation is disposed
of in a landfill at end of life.
References
Life Cycle Data
Energy Information Administration, Short-Term Energy Outlook—November 2006
(Washington, DC: U.S. Department of Energy, 2006), Table WF01.
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0LCA Software. 2005. The Netherlands.
Petersen, S., Economics and Energy Conservation in the Design of New Single-Family
Housing (NBSIR 81-2380) (Washington, DC: National Bureau of Standards, 1981).
Rushing, A.S. and Fuller, S.K., Energy Price Indices and Discount Factors for Life-Cycle Cost
Analysis -April 2006, NISTIR 85-3273-21 (Washington, DC: National Institute of Standards
and Technology, April 2006).
97 Petersen, S., Economics and Energy Conservation in the Design of New Single-Family Housing, NBSIR 81-
23SO(Washington, DC: National Bureau of Standards, 1981).
98 Energy Information Administration, Short-Term Energy Outlook—November 200<5(Washington, DC: U.S.
Department of Energy, 2006), Table WF01.
99 Rushing, A. S. and Fuller, S.K., Energy Price Indices and Discount Factors for Life-Cycle Cost Analysis -April
2006, NISTIR 85-3273-21 (Washington, DC: National Institute of Standards and Technology, April 2006).The year
30 DOE cost escalation factor is assumed to hold for years 31-50.
108
-------
Industry Contacts
Daniel Lea, Cellulose Insulation Manufacturers Association (July 2007).
3.5.2 Generic Fiberglass
Fiberglass batt insulation is made by forming spun-glass fibers into batts. At an insulation plant,
the product feedstock is weighed and sent to a melting furnace. The raw materials are melted in a
furnace at very high temperatures. Streams of the resulting vitreous melt are either spun into
fibers after falling onto rapidly rotating flywheels or drawn through tiny holes in rapidly rotating
spinners. This process shapes the melt into fibers. Glass coatings are added to the fibers that are
then collected on conveyers. The structure and density of the product is continually controlled
by the conveyer speed and height as it passes through a curing oven. The cured product is then
sawn or cut to the required size, such as for a batt. Off-cuts and other scrap material are recycled
back into the production process.
BEES performance data are provided for fiberglass batt insulation with thermal resistance values
of R-13, R-15, and R-19 for a wall application, and R-38 for a ceiling application.
Blown fiberglass insulation is made by forming spun-glass fibers using the same method as for
batts but leaving the insulation loose and unbonded. For loose fill fiberglass insulation, BEES
performance data are provided for a thermal resistance value of R-38 for a ceiling application.
The tables below specify fiberglass insulation by type and R-value:
Table 3.40: Fiberglass Bat^Mass by_ Aj)£lication
Thickness Density Mass per Functional Unit
Application cm (in) kg/m3 (Ib/ft3) kg/n? (oz/ft2)^
__„____ 8^9(15) 12T(0?76) f07(3l2)
Wall-R-15 8.9(3.5) 22.6(1.41) 2.01(6.58)
Wall-R-19 15.9(6.25) 7.0(0.44) 1.11(3.65)
CeiHng--R-38 30.5 (12.0) 1ZI2-1§) 2.35
Table 3.41: Blown Fiberglass Mass_ bg Application
Thickness Density Mass per Functional Unit
Application cm (in) kg/m3 (lb/f/) kg/m2 (oz/ft2)
^CeUing^R-38 ................... 37.704.8) ............. M^0;55) ...................... 3;32i(10;9) .................
The detailed environmental performance data for these products may be viewed by opening the
following files under the File/Open menu item in the BEES software:
• B2012B.DBF — Fiberglass Batt R-19
• B2012C. DBF— Fiberglass Batt R-15
• B2012E.DBF — Fiberglass Batt R-13
109
-------
• B3012B.DBF—Fiberglass BattR-38
• B3012D.DBF—Blown Fiberglass R-38
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
Fiberglass Insulation Production
Functional Unit of
Fiberglass
Insulation
Figure 3.17: Fiberglass Insulation System Boundaries
Raw Materials
Fiberglass insulation is made with a blend of sand, limestone, soda ash, and recycled glass cullet.
Recycled window, automotive, or bottle glass is increasingly used in the manufacture of glass
fiber, and it now accounts for approximately 30 % to 50 % of the raw material input. The
recycled content is limited by the amount of usable recycled material available in the market -
not all glass cullet is of sufficient quality to be used in the glass fiber manufacturing process. The
use of recycled material has helped to steadily reduce the energy required to produce insulation
products.
The raw materials used to produce fiberglass insulation are show in the following Table.
110
-------
Table_ 3.42: Fiberglass Insulation Constituents
„ . Batt Loose Fill
Constituent ,. „ . ,n/. ,. „ . /n/.
Mass Fraction (%] Mass Fraction (%l
Soda Ash
Borax
Glass Gullet
Limestone
Binder Coatings
Sand
9
12
34
9
5
31
9
13
35
9
<1
33
The life cycle environmental profiles for the constituents of fiberglass insulation are based on
life cycle data from the SimaPro software tool and data from the U.S. LCI Database.
Manufacturing
Energy Requirements and Emissions. The energy requirements for melting the glass
constituents into fibers and drying of the completed batt involve a mixture of natural gas and
electricity. The energy demands are outlined in the following Table.
Table 3.43: Energy Re^mr£ments£or_ Fiberglass^ Insulation Manufacturing
Energy Carrier MJ/kg_ (Btu/lbJ
_____ _____
Electricity 1.37(591)
ITO^
The manufacturing process generates air emissions from the combustion of the fuels used to melt
the raw materials and from the drying of the insulation material prior to cutting and packaging.
Emissions from fuel combustion are captured in the fuel use data included in the BEES model;
additional emissions are listed in the Table below.
Table 3.44: Enmsionsjor FJberglass Insulation Manufacturing
Emission Bonded Batts Unbonded Loose Fill
M/k$ Qb/ton). g/kg Qb/ton)
______ ______ _______
VOC 0.759(1.518) 0.083(0.165)
Transportation. The raw materials are all shipped to the manufacturing plant via diesel truck.
The average shipping distances are as follows:
ill
-------
Table 3.45: Raw Material Transportation Distances
Constituent Distance to Plant
km (mi)
Borax 805 (500)
Soda Ash 805 (500)
Glass Gullet 161 (100)
Limestone 161 (100)
Binder Coatings 322 (200)
Sand 161 (100)
Waste. All waste produced during the cutting and blending process is either recycled into other
insulation materials or added back into the glass mix. Thus, no solid waste is generated during
the production process.
Transportation
Transportation of fiberglass insulation by heavy-duty truck to the building site is modeled as a
variable of the BEES system.
Installation
Fiberglass insulation has a functional lifetime of more than 50 years - there is no need to replace
or maintain the insulation during normal building use. During the installation of fiberglass batts
and loose fill insulation, any waste material is added into the building shell where the insulation
is installed - there is effectively no installation waste.
Installing batt insulation is primarily a manual process; no energy or emissions are included in
the model. For blown fiberglass insulation, a diesel generator is used to blow the insulation
material into the ceiling space. For one h of operation, a typical 18 kW (25 hp) diesel engine can
blow 818 kg (1 800 Ib) of insulation. No other installation energy is required.
Use
It is important to consider thermal performance differences when assessing environmental and
economic performance for insulation product alternatives. Thermal performance affects building
heating and cooling loads, which in turn affect energy-related LCA inventory flows and building
energy costs over the 50-year use stage. Since alternatives for ceiling insulation all have R-38
thermal resistance values, thermal performance differences are at issue only for the wall
insulation alternatives.
For wall insulation, thermal performance differences are separately assessed for 14 U.S. cities
spread across a wide range of climate and fuel cost zones, and for electricity, distillate oil, and
natural gas heating fuel types (electricity is assumed for all cooling). When selecting wall
insulation alternatives for analysis, the BEES user selects the U.S. city closest to the building
location and the building heating fuel type, so that thermal performance differences may be
customized to these important contributors to building energy use. A NIST study of the
economic efficiency of energy conservation measures (including insulation), tailored to these
cities and fuel types, is used to estimate 50-year heating and cooling requirements per functional
112
-------
unit of insulation. 10° BEES environmental performance results account for the energy-related
inventory flows resulting from these energy requirements. To account for the 50-year energy
requirements in BEES economic performance results, 2005-2006 winter fuel prices by U.S.
region101 and U.S. Department of Energy fuel price projections over the next 30 years102 are used
to compute the present value cost of operational energy per functional unit for each R-value.
End of Life
While fiberglass insulation is mostly recyclable, it is assumed that all of the insulation is
disposed of in a landfill at end of life.
References
Life Cycle Data
Energy Information Administration, Short-Term Energy Outlook—November 2006
(Washington, DC: U.S. Department of Energy, 2006), Table WF01.
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0LCA Software. 2005. The Netherlands.
Petersen, S., Economics and Energy Conservation in the Design of New Single-Family
Housing (NBSIR 81-2380) (Washington, DC: National Bureau of Standards, 1981).
Rushing, A.S. and Fuller, S.K., Energy Price Indices and Discount Factors for Life-Cycle Cost
Analysis -April 2006, NISTIR 85-3273-21 (Washington, DC: National Institute of Standards
and Technology, April 2006).
Industry Contacts
Clarke Berdan II, Owens Corning (January 2006 - May 2006)
Paul R. Bertram, North American Insulation Manufacturers Association (July 2007)
3.5.3 Generic Mineral Wool
Blown mineral wool insulation is made by spinning fibers from natural rock (rock wool) or iron
ore blast furnace slag (slag wool). Rock wool and slag wool are manufactured by melting the
constituent raw materials in a cupola. A molten stream is created and poured onto a rapidly
spinning wheel or wheels. The viscous molten material adheres to the wheels and the centrifugal
force throws droplets of melt away from the wheels, forming fibers. The fibers are then
collected and cleaned to remove non-fibrous material. During the process a phenol
formaldehyde binder and/or a de-dusting agent are sometimes applied to reduce free, airborne
wool during application.
100 Petersen, S., Economics and Energy Conservation in the Design of New Single-Family Housing, NBSIR 81-
2380 (Washington, DC: National Bureau of Standards, 1981).
101 Energy Information Administration, Short-Term Energy Outlook—November 2006 (Washington, DC: U.S.
Department of Energy, 2006), Table WF01.
102 Rushing, A.S. and Fuller, S.K., Energy Price Indices and Discount Factors for Life-Cycle Cost Analysis -
April 2006, NISTIR 85-3273-21 (Washington, DC: National Institute of Standards and Technology, April
2006).The year 30 DOE cost escalation factor is assumed to hold for years 31-50.
113
-------
BEES performance data are provided for a thermal resistance value of R-13 for a wall
application and R-38 for a ceiling application. The Table below specifies mineral wool
insulation for these applications.
Application
_______
Ceiling-R-38
Thickness Density Mass per Functional Unit
7.9(3.1)
30.6(12.1)
64.1 (4.00)
27.2(1.70)
5.06(1.04)
8.34(1.71)
The detailed environmental performance data for these products may be viewed by opening the
following files under the File/Open menu item in the BEES software:
• B2012D.DBF—Blown Mineral Wool R-13
• B3012C.DBF—Blown Mineral Wool R-38
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
Mineral Wool Insulation Production
Trans port to
Construction
Site
Blowing
Energy
Diabase
Produc
Function
Insu
/
—1
Insu
Prod
/
al Unit of
IWool
ation
^
IWool
ation
ction
^
End-of-Life
Rock Iron Slag
tion Recovery
Coke
Production
Process
Energy
Raw Material
Transport
Figure 3.18: Mineral Wool Insulation System Boundaries
Raw Materials
Mineral wool can be manufactured using iron ore slag (slag wool) or natural diabase or basalt
rock (rock wool). Some products contain both materials; about 80 % of North American mineral
wool is manufactured using iron ore slag. Loose fill mineral wool insulation is generally
unbonded, that is, no resin is used to bind the fibers together. The BEES model for this product
114
-------
represents a weighted mix of the different types of mineral wool insulation used in North
America, as given in the Table below.
Wool InsulationConstUuents
Diabase
Rock/Basalt
Iron Ore Slag 78
maeieieieieieiei^^
The life cycle environmental profiles for the constituents of mineral wool insulation are based on
surrogate life cycle data in the SimaPro software tool and the U.S. LCI Database.
Manufacturing
Energy Requirements and Emissions. The energy requirements for melting the product
constituents into fibers and drying of the fibers involve a mixture of coke and electricity. The
energy demands are outlined in the following Table.
Table 3.48: Enerjjy^Jtequirjsrnjsnts^^
^Energy^Carrier _ MI^K.1.^U.^P.L................
Coke 6.38 (2740)
Electricity 1.0(430)
__^^
The manufacturing process generates air emissions from the combustion of the fuels used to melt
the raw materials and from the drying on the insulation material prior to packaging. Emissions
from fuel combustion are captured in the fuel use data included in the BEES model; additional
emissions are included in the Table below.
Table 3.49: Emissj^^
Emission Unbonded Loose Fill
Particulates 2.061(4.122)
Transportation. The raw materials are all assumed to be shipped 161 km (100 mi) to the
manufacturing plant via diesel truck.
Waste. All waste produced during the production process is either recycled into other insulation
materials or added back into the melt. Therefore, no solid waste is generated during the
production process.
Transportation
Transportation of mineral wool insulation by heavy-duty truck to the building site is modeled as
115
-------
a variable of the BEES system.
Installation
Mineral wool insulation has a functional lifetime of more than 50 years - there is no need to
replace or maintain the insulation during normal building use. During the installation of loose
fill insulation, any waste material is added into the building shell where the insulation is installed
- there is effectively no installation waste.
A diesel generator is used to blow the insulation material into the building shell. For one h of
operation, a typical 18 kW (25 hp) diesel engine can blow 818 kg (1 800 Ib) of insulation. The
emissions and energy use for the generator are included in the system boundaries for this
product. No other installation energy is required.
Use
It is important to consider thermal performance differences when assessing environmental and
economic performance for insulation product alternatives. Thermal performance affects building
heating and cooling loads, which in turn affect energy-related LCA inventory flows and building
energy costs over the 50-year use stage. Since alternatives for ceiling insulation all have R-38
thermal resistance values, thermal performance differences are at issue only for the wall
insulation alternatives.
For wall insulation, thermal performance differences are separately assessed for 14 U.S. cities
spread across a wide range of climate and fuel cost zones, and for electricity, distillate oil, and
natural gas heating fuel types (electricity is assumed for all cooling). When selecting wall
insulation alternatives for analysis, the BEES user selects the U.S. city closest to the building
location and the building heating fuel type, so that thermal performance differences may be
customized to these important contributors to building energy use. A NIST study of the
economic efficiency of energy conservation measures (including insulation), tailored to these
cities and fuel types, is used to estimate 50-year heating and cooling requirements per functional
unit of insulation.103 BEES environmental performance results account for the energy-related
inventory flows resulting from these energy requirements. To account for the 50-year energy
requirements in BEES economic performance results, 2005-2006 winter fuel prices by U.S.
region104 and U.S. Department of Energy fuel price projections over the next 30 years105 are used
to compute the present value cost of operational energy per functional unit for each R-value.
End of Life
While mineral wool insulation is mostly recyclable, it is assumed that all of the insulation is
disposed of in a landfill at end of life.
103 Petersen, S., Economics and Energy Conservation in the Design of New Single-Family Housing, NBSIR 81-
23SO(Washington, DC: National Bureau of Standards, 1981)
104 Energy Information Administration, Short-Term Energy Outlook—November 2006 (Washington, DC: U.S.
Department of Energy, 2006), Table WF01.
105 Rushing, A.S. and Fuller, S.K., Energy Price Indices and Discount Factors for Life-Cycle Cost Analysis -
April 2006, NISTIR 85-3273-21 (Washington, DC: National Institute of Standards and Technology, April
2006).The year 30 DOE cost escalation factor is assumed to hold for years 31-50.
116
-------
References
Life Cycle Data
Energy Information Administration, Short-Term Energy Outlook—November 2006
(Washington, DC: U.S. Department of Energy, 2006), Table WF01.
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0LCA Software. 2005. The Netherlands.
Petersen, S., Economics and Energy Conservation in the Design of New Single-Family
Housing (NBSIR 81-2380) (Washington, DC: National Bureau of Standards, 1981).
Rushing, A.S. and Fuller, S.K., Energy Price Indices andDiscount Factors for Life-Cycle Cost
Analysis -April 2006, NISTIR 85-3273-21 (Washington, DC: National Institute of Standards
and Technology, April 2006).
Industry Contacts
Anders Schmidt, dk-Teknik Energy & Environment (November 2005 - January 2006)
3.6 Framing
3.6.1 Generic Steel Framing
Steel is an important construction framing material. Cold-formed steel studs for framing are
manufactured from blanks sheared from sheets cut from coils or plates, or by roll-forming coils
or sheets. Both these forming operations are done at ambient temperatures. Cold-formed steel
shapes are made from flat-rolled 0.46 mm to 2.46 mm) (18 mil to 97 mil) carbon steel as either
single bent shapes or bent shapes welded together. Two basic types of steel framing, nailable
and nonnailable, are available in both punched and solid forms. Zinc chromate primer,
galvanized, and painted finishes are available. Steel stud and joist systems have been adopted as
an alternative to wood and masonry systems in most types of construction. Steel framing is also
used extensively for interior partitions because it is fire-resistant, easy to erect, and makes
installation of utilities more convenient. Cold-formed steel framing can be installed directly at
the construction site or it can be prefabricated off- or on-site for quicker installation. The
assembly process relies on a number of accessories usually made of steel, such as bridging, bolts,
nuts, screws, and anchors, as well as devices for fastening units together, such as clips and nails.
The functional unit of comparison for BEES framing alternatives is 0.09 m2 (1 ft2). The steel
framed exterior wall has 33 mil galvanized steel studs placed 61 cm (24 in) on center, and has a
service life of 75 years. Self-tapping steel screws, used as fasteners for the steel studs, are
included. While the exterior wall is constructed as an assembly with sheathing components and
insulation, for the BEES framing category, only the framing material is accounted for, not the
full assembly.
The detailed environmental performance data for this product may be viewed by opening the file
B2013A.DBF under the File/Open menu item in the BEES software.
117
-------
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
Steel Framing Production
Transport to
Construction
Site
N!
Functional Unit of
Steel Framing
Figure 3.19: Steel Framing System Boundaries
Raw Materials and Manufacturing
BEES modeling of the production of raw materials necessary for steel stud and fastener
manufacture is based on data from the American Iron and Steel Institute (AISI) and the
International Iron and Steel Institute (IISI), which represent late 1990s world-wide production of
steel and account for recycling loops. Energy requirements and emissions from manufacturing
cannot be itemized, since the industry data are in fully-aggregated form.
Secondary data were obtained from LCA databases and published literature.
Transportation
Transportation of the steel framing by heavy-duty truck to the building site is modeled as a
variable of the BEES system.
Installation
During installation of the steel stud framing, 1 % of the installation materials are assumed to be
lost as waste, which is recycled by contractors following "green building" practices.
Approximately 0.0056 kg (0.0123 Ib) of galvanized steel screws are assumed to be used per ft2
of steel framing. The installation of the framing is assumed to be a manual process, so no energy
inputs or emissions are included in the model.
118
-------
Use
Steel framing is assumed to have a useful life of 75 years. This is a conservative value; steel
studs have a very long life due to their galvanized treatment.
End of Life
All the steel framing and its components are assumed to be recycled at end of life.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Industry Contacts
Bill Heenan, President, Steel Recycling Institute (January 2006)
Greg Crawford, Vice President, Steel Recycling Institute (January 2006)
3.6.2 Generic Wood Framing
Wood framing is the most common structural system used for non-load-bearing and load-bearing
interior and exterior walls, and consists of lumber and specific applications of treated lumber.
The load-bearing walls support floors, ceilings, roof and lateral loads, and nonbearing walls
carry only their own weight. Interior walls can be either non-load bearing or load bearing,
whereas all exterior walls should be considered load bearing. Exterior walls are comprised of
one or two top and bottom plates and vertical studs. Sheathing or diagonal bracing ensures lateral
stability. When the wall is on a concrete foundation or slab, building code requires that the sill or
sole plate (also called bottom plate) that is in contact with the concrete must be treated wood.
In general, dimensions for framing lumber are given in nominal in, that is, 2x4 and 2x6, but the
actual dimensions of a 2x4 are 3.8 cm x 8.9 cm (1.5 in x 3.5 in) and of a 2x6, 3.8 cm x 14 cm
(1.5 in x 5.5 in). Framing lumber must be properly grade-marked to be acceptable under the
major building codes. Such grade marks identify the grade, species or species group, seasoning
condition at time of manufacture, producing mill, and the grading rules-writing agency.
Wood studs are produced in a sawmill, where harvested wood is debarked and sawn into specific
dimensions. The lumber is then dried in a controlled environment until the desired moisture
content (between 12 % and 19 %) is reached. Framing lumber may be treated with preservatives
in order to guard against insect attack or fungal decay. Treated lumber is used for any application
where wood is in contact with concrete or the ground. All wood, including framing, used in
places with serious termite problems, such as in Hawaii, must be treated.
The functional unit of comparison for BEES framing alternatives is 0.09 m2 (1 ft2) of load-
bearing exterior wall. The wood-framed wall consists of wood studs placed 41 cm (16 in) on
center, and has a service life of 75 years. While the exterior wall is constructed as an assembly
with sheathing components and insulation, for the BEES system, only the framing material—
either treated or untreated wood—is accounted for, not the full assembly.
119
-------
The detailed environmental performance data for these products may be viewed by opening the
file B2013B.DBF, for treated wood framing, and B2013C.DBF, for untreated wood framing,
under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
Wood Framing Production
Functional Unit of
Wood Framing
Figure 3.20: Wood Framing System Boundaries
Raw Materials
For BEES, data were collected for the harvested trees used to produce the dimension lumber
necessary for framing load-bearing walls. The lumber is primarily produced in the Pacific
Northwest (PNW) and the Southeastern United States (SE). For PNW the species of wood used
are Douglas Fir and Western Hemlock, while for SE the wood species is Southern Yellow Pine,
which is actually a group of six different softwood species.
The data to grow and harvest softwood logs for a composite forest management scenario for
PNW and SE is found in a study by CORREVI.106 The growing and harvesting of wood includes a
mix of low-, medium-, and high-intensity managed timber. Energy use for wood production
includes electricity for greenhouses to grow seedlings, gasoline for chain saws, diesel fuel for
106 Bowyer, J., et. al., Phase I Final Report: Life Cycle Environmental Performance of Renewable Building
Materials in the Context of Residential Construction. (Seattle, WA: Consortium for Research on Renewable
Industrial Materials-- CORRIM, Inc./University of Washington, 2004). Found at: http://www.corrim.org/reports;
data also submitted to US LCI Database.
120
-------
harvesting mechanical equipment, and a small amount of fertilizer. Emissions associated with
production and combustion of gasoline and diesel fuel, and those for the production and delivery
of electricity, are based on the U.S. LCI Database. Fertilizer production data is adapted from
European data in the U.S. LCI Database. Electricity use for greenhouse operation is based on the
grids for the regions where the seedlings are grown, while the U.S. average electricity grid is
used for fertilizer production. BEES adopts the CORRIM study's equally-weighted average of
forest management practices in PNW and SE. The weight of wood harvested for lumber is based
on an average oven-dry density of 510 kg/m3 (31.8 lb/ft3).
BEES modeling accounts for the absorption of carbon dioxide by trees as they grow; the carbon
becomes part of the wood, and the oxygen is released to the atmosphere. The "uptake" of carbon
dioxide from the atmosphere during the growth of timber is about 1.84 kg (4.06 Ib) of carbon
dioxide per kilogram of harvested wood (in oven-dry weight terms).
Chromated Copper Arsenate (CCA), the lumber treatment assumed in previous versions of
BEES, is no longer permitted for use in the United States. An article from the Treated Wood
Council website reports that alkaline copper quaternary (ACQ), a copper-based preservative, is
the most popular replacement preservative for CCA.107 This contains 66.7 % copper oxide and
33.3 % didecyldimethyl ammonium chloride. The data used in BEES for copper oxide is based
on European data for copper production, provided by the SimaPro database. For lack of better
available data, proxy data was used to represent didecyldimethyl ammonium chloride; esterquat,
a type of quaternary ammonium, was used as the proxy, and its production data comes from a
European study on detergents.108 The treated wood in BEES is assumed to contain 4.0 kg/m3
(0.25 lb/ft3) ACQ.109
Manufacturing
Energy Requirements and Emissions. The energy requirements allocated to the production of
softwood lumber for wood framing are listed in the Table below. These requirements are based
on average manufacturing conditions in the PNW and SE regions of the United States. The
energy comes primarily from burning wood and bark waste generated in the sawmill process.
Other fuel sources include natural gas for boilers, and propane and diesel for forklifts and log
haulers at the sawmill. The production and combustion of the different types of fuel are based on
the U.S. LCI Database. The electricity grid used is an average by fuel breakdown for both
regions.
107 Frome, A., "Wood Treaters Switch to New Chemical," Timber-Line Online Newspaper (April 2004). Found at:
http://www.treatedwood.com/news/industry_articles/new_chemical_040104.pdf.
108 Dall'Acqua, S., et al., Report #244 (St. Gallen: EMPA, 1999).
109 Southern Pine Council, "Table 12: AWPA Standards for Softwood Lumber & Plywood," Southern Pine Use
Guide (Kenner, LA: Southern Pine Council, 2003), pp. 17. Found at:
http://www.southernpine.com/awpatablel 03.pdf.
121
-------
Energy Carrier Quantity per Ib Lumber Quantity per Ib Lumber
inSE
Electricity 1.80E+05 J (0.05 kWh) 2.88E+05 J (0.08 kWh)
Natural Gas 4.81E-08 L (1.7E-09 ft3) 23 L (0.82 ft3)
Diesel fuel 0.56 mL (1.5 E-04 gal) 0.98 mL (2.6 E-04 gal)
Kerosene 0.001 mL (3.8 E-07 gal)
LPG 7.95E-05 mL (2. 1 E-08 gal) 2.69E-04 mL (7. 1 E-08 gal)
Gasoline 0.05 mL (1 .2 E-05 gal) 0.06 mL (1 .7 E-05 gal)
Hogfuel/Biomass ng ?3
_(over>dry_£asis)
The allocated process-related air emissions from lumber production are based on the CORRIM
study and reported in the Table below. Allocation is based on mass and a multi-unit process
analysis to correctly assign burdens. Note: In the BEES model, CC>2 generated by combustion of
biofuel (hogged wood fuel) and fossil fuel are tracked separately since CC>2 from biomass is
considered environmentally impact-neutral by the U.S. EPA, and as such is not considered when
determining the Global Warming Potential impact.
Air Emission Quantity per Ib Quantity per Ib
_ Lju^nbjerj^
Particulates (unspecified) 0.44 g (9.7 E-04 Ib) 0.01 g (3.0 E-05 Ib)
Treating Wood. Data for treating wood comes from a treated lumber producer.110 Lumber is put
into a vacuum chamber where air is removed from the wood cells. Preservative is pumped into
the chamber, and with the pressure in the chamber raised, the preservative is forced into the
wood. At the end of the treatment, a vacuum removes excess preservative from wood cells.
Transportation. Sawmills are often located close to tree harvesting areas. For transportation of
logs to the sawmill, CORRIM surveys report an average truck transportation distance of 103 km
(64 mi) for harvested wood. The delivery distances are one-way with an empty backhaul. For
preservative-treated lumber, truck transportation of 322 km (200 mi) is assumed for transport of
the preservative.
Transportation
Transportation of wood framing by heavy-duty truck to the building site is modeled as a variable
of the BEES system.
The weight of wood shipped includes its moisture content. For the shipping weight of lumber,
the oven-dry density of lumber, 510 kg/m3 (31.8 lb/ft3), plus its moisture content of 19 % (an
1 See www.follen.com/faq.htmMq3.
122
-------
additional 97 kg of water), yields a shipping weight of 607 kg/m3 (37.9 Ib/ft3). The ACQ-treated
lumber is usually shipped green, so a 40 % to 60 % moisture content is assumed.
Installation
Installation of wood framing is assumed to be done primarily by manual labor, so there are no
installation emissions. It is assumed that wood studs are placed 16 in on center and are fastened
with galvanized steel nails. Production of the galvanized steel for nails is based on data from the
International Iron and Steel Institute.111
At installation, 5 % of the product is lost to waste, and all of this waste is disposed of in a
landfill. It is assumed that 0.04 kg (0.09 Ib) of galvanized nails are needed to install the framing.
Use
Based on U.S. Census data, the mid-service life of a wood-framed house in the United States is
over 85 years. To be conservative, CORRIM assumes a life of 75 years for the residential shell,
including wood framing. The product is therefore assumed to have a useful life of 75 years.
There is no routine maintenance for the framing over its lifetime. The building envelope (roof
and siding) should be maintained to ensure water tightness and prevent water damage to the
shell.
End of Life
All the wood framing is assumed to be disposed of in landfill at end of life. The practice of
recycling is increasing, but data are not available to quantify this practice.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Bowyer, J., et. al., Phase I Final Report: Life Cycle Environmental Performance of Renewable
Building Materials in the Context of Residential Construction. (Seattle, WA: Consortium for
Research on Renewable Industrial Materials. (CORRIM, Inc.)/University of Washington,
2004). Found at: http://www.corrim.org/reports.
Frome, A., "Wood Treaters Switch to New Chemical," TimberLine Online Newspaper (April
2004). Found at:
http://www.treatedwood.com/news/industry _articles/new_chemical_040104.pdf
Dall'Acqua, S., et al., Life Cycle Inventories for the Production of Detergent Ingredients,
Report #244 (St. Gallen: BMP A, 1999).
Southern Pine Council, "Table 12: AWPA Standards for Softwood Lumber & Plywood,"
Southern Pine Use Guide, (Kenner, LA: Southern Pine Council, 2003), pp. 17. Found at:
http ://www. southernpine. com/awpatable 1 03 .pdf.
111 Life Cycle Inventory Data Sheet for Steel Products issued to First Environment in January 2006. Data
represent the years 1999-2000.
123
-------
Industry Contacts
Jim Wilson, Oregon State University/CORRIM, Inc. (August 2005-Jan 2006)
3.7 Exterior Sealers and Coatings
3.7.1 BioPreserve SoyGuard Wood Sealer
Produced by BioPreserve in Erie, Pennsylvania, SoyGuard Premium Water Repellent & Wood
Sealer is a biobased, non-toxic exterior wood coating with a weak odor and low VOC. It can be
applied to new, old, and pressure-treated wood surfaces that are exposed to moisture and
weather, such as outdoor decks, siding, furniture, fences, and doors. SoyGuard contains methyl
soyate, a natural solvent derived from soybean oil that penetrates the wood surface and
encapsulates wood cells with a protective polymer resin made from recycled polystyrene.
For the BEES system, the functional unit for the sealer and coating category is sealing or coating
9.29 m2 (100 ft2) of surface. At an application rate of 23.2 m2 (250 ft2) per gal and a density of
3.4 kg (7.5 Ib) per gal, this amounts to use of 1.36 kg (3 Ib) of SoyGuard per application. The
detailed environmental performance data for this product may be viewed by opening the file
B2040A.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product as it is
modeled for BEES.
BioPreserve SoyGuard Wood Sealer
Recycled
EPS
Fertilizer
production
Agrichemicals
production
Figure 3.21: SoyGuard System Boundaries
124
-------
Raw Materials
The SoyGuard constituents are used in the following proportions.
Table 3.52: SoyGuard Constituents
Constituent Mass Fraction (%)
Methyl Soyate 92
_Rec^cled_exganded polystyrene (EPS) 8
Methyl soyate production data comes from the life cycle data for biodiesel production developed
for a U.S. Department of Agriculture (USDA) study that compared petroleum-based diesel fuel
to biodiesel.112 Data for soybean production comes from the U.S. LCI Database.
The production of virgin extruded polystyrene (EPS) is not accounted for since recycled EPS is
used in the product, but data for recycling the EPS is included and encompasses the following
subprocesses: collection at end of life, shredding and grinding, milling, separation, and
granulation. This data is 1990s European data on mixed polymers and comes from the SimaPro
database. Transportation of the recycled EPS to the BioPreserve plant is included.
Manufacturing
Energy Requirements. Data to heat and mix the materials into the final product is calculated
using the energy consumed and quantity produced in an 8-h shift, and amounts to 0.0022
kWh/kg (0.001 kWh/lb) of product. Electricity is modeled using the U.S. average electricity grid
from the U.S. LCI Database. A small amount of volatile organic compounds (VOC) and
particulate emissions are released during the process: 1.4 E-5 kg (3.0 E-5 Ib) of VOC and 1.4 E-6
kg (3.0 E-6 Ib) of particulates per Ib of SoyGuard produced. A small amount of solid waste is
generated as well: 4.5 E-7 kg (1.0 E-6 Ib) of filtered solid particles from recycled EPS per Ib of
SoyGuard produced. All of these outputs are accounted for in the BEES product model.
Transportation. Methyl soyate is transported approximately 1368 km (850 mi) to the plant,
while the EPS comes from only 8 km (5 mi) away. Materials are transported by diesel truck,
which is modeled based on the U.S. LCI Database.
Transportation
As a default, product transport to the customer is assumed to average 563 km (350 mi) by diesel
truck, modeled based on the U.S. LCI Database. The BEES user is free to change the default
transportation distance.
Installation and Use
SoyGuard requires that one thin coat be applied with a brush, roller, or power sprayer, but for the
product to be fully effective it must be applied only at a rate the surface can absorb. For BEES,
SoyGuard is modeled as being manually applied. One application lasts approximately 2 years.
As with all BEES products, re-application over the 50-year use period-a total of 25 applications
in all-is accounted for in the model.
112 Sheehan, J. et al, NREL/SR-580-24089 (Washington, DC: US Department of Agriculture and US
Department of Energy, May 1998).
125
-------
End of Life
No end-of-life is modeled since the product is fully consumed during the use phase.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Sheehan, J. et al., Life Cycle Inventory of Biodiesel and Petroleum Diesel for Use in an Urban
Bus, NREL/SR-5 80-24089 (Washington, DC: U.S. Department of Agriculture and U.S.
Department of Energy, May 1998).
BioPreserve, SoyGuard Wood Protection Premium Water Repellent and Sealer: Product
Information and Application Instructions. Found at: http://www.biopreserve.com.
Industry Contacts
Brad Davis, BioPreserve (January 2006)
3.8 Roof Coverings
3.8.1 Generic Asphalt Shingles
Asphalt shingles, available in a wide range of colors and styles, are suitable for use on roofs with
pitches from 2:12 to 21:12.113'114 Asphalt shingles are commonly made from fiberglass mats
impregnated and coated with a mixture of asphalt and mineral filler for both a decorative finish
and a wearing layer. The shingles are nailed over roofing underlayment installed over a deck of
sheathing, typically oriented strand board.
The market for asphalt shingles has changed significantly in the past 10 years, from primarily 3-
tab shingles to now over 56 % of the market consisting of laminated/multi-layered products.
Laminate asphalt shingles typically are available in dimensions of 30 cm by 91 cm (12 in by
36 in). Roof coverings such as asphalt shingles are evaluated in BEES on the basis of a
functional unit of roof area covered: 1 square (9.29 m2, or 100 ft2). Allowing for the
recommended overlap, a typical number of shingles required to cover one square is about 80
standard shingles or 65 metric shingles, with an average weight of about 14 kg/m2 (280
lb/square).115
The type of underlayment used has typically been asphalt-impregnated organic felt, although
self-adhering polymer modified bituminous sheet materials have been experiencing 20 % to
30 % growth in use over the past several years. For roof pitches from 3:12 to 4:12, two layers of
113
114
Pitch ratio expressed as rise in in: run in in.
Asphalt Roofing Manufacturers Association (ARMA), Asphalt Roofing Manufacturers Association (ARMA)
Residential Asphalt Roofing Manual (Calverton, MD: Asphalt Roofing Manufacturers Association, 1997) pp. 17.
115 Shingle dimensions and weight per square based on survey of product information available in ICC reports on
laminated asphalt shingles produced by various manufacturers (http://www.icc-
es.org/reports/index.cfm?search=searchX Number of shingles per square from survey of laminated asphalt shingle
products on ebuild.com.
126
-------
Type-15 felt underlayment are used, while roof pitches greater than 4:12 shed water more
quickly and thus require only one layer of Type-15 felt.116
For BEES, a roof covering of asphalt laminated shingles with a 20-year life, installed with one
layer of type-15 roofing underlayment and galvanized steel nails, is analyzed. The roof sheathing
is not considered in the analysis. The detailed environmental performance data for this product
may be viewed by opening the file B3011A.DBF under the File/Open menu item in the BEES
software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
Asphalt Shingles
Limestone
Production
Dolomite
Production
Figure 3.22: Asphalt Shingles System Boundaries
Raw Materials
The composition of asphalt shingles is shown in the Table below. Granules production is
modeled as rock mining and grinding.
' Crowe, J. P. "Steep-slope roof systems require different underlayment installations." Professional Roofing
(May 2005).
127
-------
Table 3.53_: As£halt_ Shingle Constituents
Constituent
Asphalt
Filler
Fiberglass Mat
Granules
Back surfacing (sand and talc)
Total
Kg/nf
(Ib/square)
2.7 (56)
5.9(120)
0.7(14)
3.4(70)
1.0(19.6)
_____
Mass Fraction
20%
43%
5%
25%
7%
ioo%"
One square is equivalent to 9.29 m2 (100 ft)
Type-15 felt consists of asphalt and organic felt. The composition is shown in the following
Table. The organic felt is assumed to consist of 50 % recycled cardboard and 50 % wood chips.
Table_ 3.54: 7jfJ>£ 15_ Felt_ Underlagmen^ Constituents^
Constituent
Asphalt
Organic Felt
Limestone
Sand
Total
Kg/nf
(Ib/square)
0.3 (5.4)
0.2 (4.8)
0.06(1.2)
0.03 (0.6)
0.6 (12)
Mass Fraction
45%
40%
10%
5%
100 %
One square is equivalent to 9.29 m2 (100 ft2)
Data for the production of underlayment materials and asphalt shingle constituents are from the
SimaPro LCA database and U.S. LCI Database.
Manufacturing
Energy Requirements and Emissions. According to the Asphalt Roofing Manufacturers
Association (ARMA), asphalt shingles are produced by nine manufacturers in about 22 states.
Data on production and combustion of fuels for shingle manufacture is from the U.S. LCI
Database.
Table 3.55: Energy_ R^quirements^or Asjjhalt^ Shingle Manufacturing
Energy Carrier^ MJ/nf (Btu/ft2}
_____ 2J(202)
Electricity 0.89 (78)
Emissions pertaining to manufacturing asphalt shingle roofing materials follow.
117
117 Trumbore, D. et al. "Emission Factors for Asphalt-Related Emissions in Roofing Manufacturing.'
Environmental Progress 24:3 (2005): 268-278.
128
-------
Air Emission Emission factor
Particulates (unspecified) 0.04 (0.08)
Sulfur oxides 0.45 (0.9)
Carbon monoxide 0.35 (0.7)
Nitrogen oxide 0.03 (0.06)
Total organic compounds 0.02 (0.04)
Transportation. Asphalt is assumed to be transported 402 km (250 mi) by truck, rail, and
pipeline in equal proportions. Limestone, sand, talc, and granules are assumed to be transported
by truck and rail, also over the same distance and in equal proportions. Fiberglass materials are
assumed to be transported the same distance by truck.
Roofing underlayment raw materials are also assumed to be transported 402 km (250 mi).
Asphalt is assumed to be transported by truck, train, and pipeline in equal proportions, while the
cardboard and wood chips are assumed to be transported by truck.
Waste. Solid wastes generated during the manufacturing process that are not internally recycled
within the process are sent off site to either be landfilled or incorporated into other products.
Transportation
Transportation of asphalt shingles by heavy-duty truck to the building site is modeled as a
variable of the BEES system. Roofing underlayment and nails are assumed to be transported 161
km (100 mi) by truck to the building site.
Installation
In areas with normal wind conditions, four nails should be used to fasten each shingle, while six
nails per shingle are recommended in high wind regions. Galvanized roofing nails should be
used, with a minimum nominal shank diameter of 12 gauge, 0.267 cm (0.105 in), and a minimum
head diameter of 0.953 cm (3/8 in).118 At four nails per shingle, 320 nails per square are required
to secure standard shingles (80 shingles/square), and 260 nails per square are required for metric
shingles (65 shingles/square). Installation of one layer of Type-15 felt underlayment is assumed
to require an additional 120 nails per square. The weight of 440 nails (for 80 standard shingles
with underlayment) is 2.2 kg (4.9 Ib) and the weight of nails for 65 metric shingles including
underlayment is 1.9 kg (4.2 Ib).
Installation of asphalt shingles is assumed to be done primarily by manual labor, so the
installation phase in BEES is free of environmental burdens; however, equipment such as
conveyors may be used to move the roofing materials from ground level to rooftop, and
compressors may be used to operate nail guns used to install roofing materials. There were not
enough data to quantify this aspect.
118 Asphalt Roofing Manufacturers Association (ARMA), Asphalt Roofing Manufacturers Association (ARMA)
Residential Asphalt Roofing Manual, pages 20-23.
129
-------
Installation waste from scrap is estimated at approximately 10 % of the installed weight.
Installation scrap is generally landfilled, although some manufacturers offer an incentive for
contractors to return scrap for recycling into shingles. Data were not available to quantify
installation scrap recycling.
Use
At 20 years, new shingles are installed over the existing shingles. No additional underlayment is
generally required, since the original roof covering left in place serves the same purpose as the
underlayment.119 At 40 years, the two layers of shingles and the original underlayment are
removed before installing replacement shingles with underlayment.
It is important to consider solar reflectivity differences among roof coverings of different
materials and colors when assessing the environmental and economic performance of roof
covering alternatives. "Cool" roofs reflect and emit solar radiation well, and thus stay cooler in
the sun than less reflective, less emissive materials. The cool temperature results in building-
scale cooling energy savings ranging from 2% to 60 %.120 A much less significant rise in
building heating energy costs also occurs. BEES accounts for solar reflectivity performance in
computing energy-related LCA inventory flows and building energy costs over the 50-year use
stage for roof covering products.
For roof coverings, thermal performance differences are separately assessed for 16 U.S. cities
spread across a range of Sunbelt climate and fuel cost zones. When selecting roof covering
alternatives for use in Sunbelt climates,121 the BEES user chooses 1) the roof covering material
and color, 2) the U.S. Sunbelt climate city closest to the building location, 3) the building type
(new or existing), 4) its heating and cooling system (electric air-source heat pump or gas
furnace/central air conditioning heating and cooling systems), and 5) its duct placement
(uninsulated attic ducts or ducts in the conditioned space), so that thermal performance
differences may be customized to these important contributors to building energy use. Energy
use data provided to the National Institute of Standards and Technology by Lawrence Berkeley
National Laboratory (and which LBL developed for the U.S. EPA Energy Star Roof Products
program), tailored to these five parameters, are used to estimate 50-year heating and cooling
requirements per functional unit of roof covering.122 BEES environmental performance results
account for the energy-related inventory flows resulting from these energy requirements (stored
in USEENVTR.DBF), and BEES economic performance results account for the present value
cost resulting from these energy requirements (stored in USEECON.DBF).
119 Ibid, p. 71.
120 Memorandum from Sarah Bretz/Lawrence Berkeley National Laboratory to Barbara Lippiatt/National
Institute of Standards and Technology, 12/18/98.
121 In cold climates, the amount of roof insulation is more important to thermal performance than the color of the
roof covering.
122 LBL data were developed for BEES by LBL's Sarah Bretz, based on Konopacki and Akbari, Simulated
Impact of Roof Surface Solar Absorptance, Attic, and Duct Insulation on Cooling and Heating Energy Use in
Single-Family New Residential Buildings, LBNL-41834, Lawrence Berkeley National Laboratory, Berkeley, CA,
1998, and on Parker et al., "Measured and Simulated Performance of Reflective Roofing Systems in Residential
Building," ASHRAE Transactions, SF-98-6-2, Vol. 104, 1998, p. 1.
130
-------
End of Life
When the two layers of shingles and underlayment are removed after 40 years, all materials
(shingles, underlayment, and nails) are assumed to be disposed of in a landfill, and are modeled
as such. However, there is a growing trend to recycle shingles into pavement products.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Trumbore, D. et al. "Emission Factors for Asphalt-Related Emissions in Roofing
Manufacturing". Environmental Progress 24:3 (2005): 268-278.
Asphalt Roofing Manufacturers Association (ARMA), Asphalt Roofing Manufacturers
Association (ARMA) Residential Asphalt Roofing Manual (Calverton, MD: Asphalt Roofing
Manufacturers Association, 1997) pp. 17.
Crowe, J. P. "Steep-slope roof systems require different underlayment installations."
Professional Roofing (May 2005) Found at
http://www.professionalroofmg.net/article.aspx?A_ID=640.
Industry Contacts
Russ Snyder, Vice President, Asphalt Roofing Manufacturers Association, December 2005 -
February 2006
3.8.2 Generic Clay Tile
Clay tiles are manufactured from clay, shale, or similar naturally-occurring earthy substances
and subjected to heat treatment at elevated temperatures (known as firing). The most commonly
used clay tiles are the one-piece "S" mission tile and the two-piece mission tile. One-piece "S"
tile accounts for about 60 % of the clay roof tile market. Red-colored tiles are still quite popular,
although there is now a wide range of colors and blends available.
Roof coverings such as clay tile are evaluated in BEES on the basis of a functional unit of roof
area covered: 1 square (9.29 m2, or 100 ft2). The weight of the one-piece "S" tile is 357 kg to 381
kg (788 Ib to 840 Ib) per square, with 75 to 100 pieces of tile per square. The two-piece mission
tile weighs approximately 476 kg (1 050 Ib) per square, with 150 pieces of tile (75 tops and 75
pans) per square.
Clay tiles are installed over a deck of wood sheathing, typically oriented strand board covered
with underlayment, which is generally asphalt-impregnated organic felt. For roof pitches from
4:12 to 10:12, two layers of Type-30 felt are used, while roof pitches of greater than 10:12 use
one layer of Type-30 felt.123
For the BEES system, a roof covering of red Spanish one-piece "S" clay tiles, one layer of Type
II No. 30 roofing felt, and galvanized nails is studied. The weight of the clay tile is 381 kg (840
123 Crowe, J. P. "Steep-slope roof systems require different underlayment installations." Professional Roofing
(May 2005).
131
-------
Ib) per square, with 75 to 100 pieces of tile per square. The detailed environmental performance
data for this product may be viewed by opening the file B301 IB.DBF under the File/Open menu
item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
Clay Tiles
Figure 3.23: Clay Roof Tile System Boundaries
Raw Materials
The clay tile is composed of fired clay. Raw material sources are typically located relatively
close to tile plants, so an 80 km (50 mi) transport distance is assumed in the model. For the
underlayment, Type II No. 30 roofing felt is used, which consists of asphalt and organic felt in
the quantities given in the Table below. The organic felt is assumed to consist of 50 % recycled
cardboard and 50 % wood chips. The production of clay and felt materials is based on the
SimaPro LCA database and U.S. LCI Database.
Mass Fraction
45%
10%
5%
40%
100 %
TableJ.57^ ^
Constituent Kg/m2
(Ib/square)
Asphalt 0.57 (12)
Organic Felt 0.51(10)
Limestone 0.13 (2.6)
Sand 0.06(1.3)
1.27(25.9)
One square is equivalent to 9.29 m (100 ft)
132
-------
Manufacturing
Energy Requirements and Emissions . In the United States, the top three (by market share) clay
roofing tile manufacturers are located in Southern California, Northern California, and Ohio. All
clay tile manufacturers use 100 % natural gas to fire the kilns; most plants, however, are at least
partially automated and use the latest technology, which requires electricity. Natural gas and
electricity use reported by one tile producer were 8.7 therms (873 390 Btu) of natural gas and
110 MJ (30.5 kWh) of electricity per 381 kg (840 Ib) square of tile. No other production data
was available; these values were taken as representative.
Table 3.j>8>:J^
Natural Gas 2.42(1 040)
Electricity 0.29 (120)
2.7 (1160)
Data on electricity generation and production and on combustion of natural gas are from the U.S.
LCI Database.
Transportation. The clay raw material is assumed to be transported 80 km (50 mi) to the
manufacturing plant, and to be evenly split between train and truck modes of transport. All
components of roofing felt are assumed to be transported 402 km (250 mi). Asphalt is assumed
to be transported by truck, train, and pipeline in equal proportions, while the cardboard and wood
chips are assumed to be transported by truck.
Waste. Clay tile scrap or rejects that occur before the firing process are recycled back into the
manufacturing process. After firing, any scrap or rejects are recycled by crushing for use on
tennis courts, baseball fields, and other applications.
Transportation
Transportation of clay tile by heavy-duty truck to the building site is modeled as a variable of the
BEES system. Roofing underlayment and nails are assumed to be transported 161 km (100 mi)
by truck to the building site.
Installation
Rollers, conveyors, or cherry pickers are used to move the tile up to the roof; however, no data
quantifying the associated energy use were available. Nailing of clay tiles is done by hand; nail
guns are not used. Galvanized steel or copper nails can be used for installation; galvanized nails
are cheaper and are more commonly used, so are assumed for the BEES analysis. For
installation, one nail per tile is used for a roof pitch less than 7:12.124 For roofs with a pitch
greater than 7:12, two nails are required per tile, or 150 to 200 nails per square. In BEES, the
tiles are assumed to be installed using one nail per tile.
Clay tile roofing requires at least one layer of Type II No. 30 felt, and one layer is assumed for
124 7:12 pitch = 7 in rise per 12 in ran.
133
-------
the model. The underlayment uses 30 to 40 "roofing top" nails per square. Each galvanized steel
nail is assumed to weigh 0.002 kg (0.004 Ib). Installation waste from scrap is estimated at 2 % to
5 % of the installed weight.
Use
Clay roof tile has a long service life. Many clay roofs have been in existence for more than one
hundred years. Clay tile generally does not need to be replaced; however, the underlayment may
need replacement after 10 years to 15 years. When the underlayment is replaced, the roof tiles
are typically reused. The tiles themselves are replaced after 70 years.
It is important to consider solar reflectivity differences among roof coverings of different
materials and colors when assessing the environmental and economic performance of roof
covering alternatives. "Cool" roofs reflect and emit solar radiation well, and thus stay cooler in
the sun than less reflective, less emissive materials. The cool temperature results in building-
scale cooling energy savings ranging from 2% to 60 %.125 A much less significant rise in
building heating energy costs also occurs. BEES accounts for solar reflectivity performance in
computing energy-related LCA inventory flows and building energy costs over the 50-year use
stage for roof covering products.
For roof coverings, thermal performance differences are separately assessed for 16 U.S. cities
spread across a range of Sunbelt climate and fuel cost zones. When selecting roof covering
alternatives for use in Sunbelt climates,126 the BEES user chooses 1) the roof covering material
and color, 2) the U.S. Sunbelt climate city closest to the building location, 3) the building type
(new or existing), 4) its heating and cooling system (electric air-source heat pump or gas
furnace/central air conditioning heating and cooling systems), and 5) its duct placement
(uninsulated attic ducts or ducts in the conditioned space), so that thermal performance
differences may be customized to these important contributors to building energy use. Energy
use data provided to the National Institute of Standards and Technology by Lawrence Berkeley
National Laboratory (and which LBL developed for the U.S. EPA Energy Star Roof Products
program), tailored to these five parameters, are used to estimate 50-year heating and cooling
requirements per functional unit of roof covering.127 BEES environmental performance results
account for the energy-related inventory flows resulting from these energy requirements (stored
in USEENVTR.DBF), and BEES economic performance results account for the present value
cost resulting from these energy requirements (stored in USEECON.DBF).
End of Life
At end of life, clay tiles are recovered and re-used. Usually, clay tile removed for underlayment
replacement is saved on a pallet for re-use on the same building. If the tile is not to be replaced
125 Memorandum from Sarah Bretz/Lawrence Berkeley National Laboratory to Barbara Lippiatt/National
Institute of Standards and Technology, 12/18/98.
126 In cold climates, the amount of roof insulation is more important to thermal performance than the color of the
roof covering.
127 LBL data were developed for BEES by LBL's Sarah Bretz, based on Konopacki and Akbari, Simulated
Impact of Roof Surface Solar Absorptance, Attic, and Duct Insulation on Cooling and Heating Energy Use in
Single-Family New Residential Buildings, LBNL-41834, Lawrence Berkeley National Laboratory, Berkeley, CA,
1998, and on Parker et al., "Measured and Simulated Performance of Reflective Roofing Systems in Residential
Building," ASHRAE Transactions, SF-98-6-2, Vol. 104, 1998, p. 1.
134
-------
on the building, the roofer will use it on another building that specifies the same tile type and
color. The trend today is that old clay tiles are in demand and are often considered more
valuable than the newly produced clay tile. Recovered clay roofing tiles are offered by
wholesalers to the public worldwide via the Internet, local advertising, and trade magazines.
Regardless of condition, used clay tile is not thrown away. All clay tile can be 100 % re-used, re-
sold, or crushed for use on tennis courts, baseball fields, and other applications.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Crowe, J. P. "Steep-slope roof systems require different underlayment installations."
Professional Roofing (May 2005).
Industry Contacts
Yoshi Suzuki, General Manager, MCA Superior Clay Roof Tile (February 2006)
3.8.3 Generic Fiber Cement Shingles
Fiber cement shingles are considered a synthetic equivalent to wood shingles. In general, these
roofing materials can last longer that wood or asphalt products. In the past, fiber cement
shingles were manufactured using asbestos fibers. Now asbestos fibers have been replaced with
cellulose fibers.
Roof coverings such as fiber cement shingles are evaluated in BEES on the basis of a functional
unit of roof area covered: 1 square (9.29 m2, or 100 ft2). For the BEES system, a 45-year fiber
cement shingle consisting of portland cement, fly ash, silica fume, sand, and cellulose fibers is
studied. The shingle size modeled is 36 cm x 76 cm x 0.4 cm (14 in x 30 in x 5/32 in). Type-30
roofing felt and galvanized nails are used for installation.
The detailed environmental performance data for this product may be viewed by opening the file
B3011C.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
135
-------
Fiber Cement Shingles
Functional Unit of
Fiber Cement
Shingles
Organic Fiber
(e.g., wood chips,
recycled new sprint)
Figure 3.24: Fiber Cement Shingles System Boundaries
Raw Materials
Fiber cement shingles are composed primarily of portland cement, fly ash, organic fiber, and
fillers. The relative proportions of these and other product constituents are provided in the
following Table.
Mass
Constituent
Mass Fraction (%)
Portland cement
Fly ash
Silica fume
Filler (sand)
Organic fiber (including wood
chips, recycled newsprint)
J'igments^oxides^
Total
6.35(1.30)
5.27(1.08)
1.29(0.26)
1.61 (0.33)
1.29(0.26)
15.93 (3.26)
40
33
8
10
100
136
-------
Production of portland cement is described under the Portland Cement Concrete Products
documentation. Fly ash is a waste product from coal combustion in electric utility boilers, and
silica fume is a waste product from the manufacture of silicon and ferrosilicon alloys. These
waste products are assumed to be environmentally "free" input materials; however, transport of
these materials to the shingle plant is included. Data for the production of other input materials is
from the SimaPro LCA database and U.S. LCI Database.
Sources of organic fiber include wood chips and recycled newsprint. The amount of each is
likely to vary by manufacturer; one manufacturer reports that recycled newsprint accounts for
3 % of the mass fraction of their product.
For the underlayment, Type II No. 30 roofing felt is used, which consists of asphalt and organic
felt as listed in the Table below. The organic felt is assumed to consist of 50 % recycled
cardboard and 50 % wood chips. The production of felt materials is based on the SimaPro LCA
database and U.S. LCI Database.
^ 3.60: Tffl^3j£ Rooming Felt_ Constituent^
Constituent Kg/m2 Mass Fraction
fib/square}
O57(TT75) 45~%
Organic Felt 0.51(10.4) 10%
Limestone 0.13(2.6) 5%
Sand 0.06(1.3) 40%
"Il^~~^
™™™™™™«™™^
One square is equivalent to 9.29 m (100 ft)
Manufacturing
Energy Requirements and Emissions. Fiber cement is manufactured by blending the raw
materials; the blend is then cured to produce shingles. Energy — of the types and amounts given
below — is required for blending and for curing of the final product. Data on production and
combustion of fuels, including electricity generation, is from the U.S. LCI Database.
Table 3. 61: Energy_ Requirements for Fiber Shingle^ Manufacturing
Energy Carrier MJ/kg_ (BtuAbJ
_____ _____
Electricity 0.69 (297)
ITO^
Transportation. Most shingle raw materials are assumed to be transported to the manufacturing
plant 402 km (250 mi) by truck. A small percentage, assumed to be approximately 2 %, of the
shingle material inputs may be transported more then 3 219 km (2 000 mi); due to economic
constraints, it is assumed that these products are transported by rail rather than by truck.
Roofing felt raw materials are also assumed to be transported 402 km (250 mi) by truck.
137
-------
Waste. No data were available on types and quantities of solid wastes generated from the shingle
manufacturing process; no waste was assumed to be generated.
Transportation
Transportation of fiber cement shingles by heavy-duty truck to the building site is modeled as a
variable of the BEES system.
Installation
Installation of fiber cement shingles is assumed to be primarily a manual process, however,
equipment such as conveyors may be used to move the roofing materials from ground level to
rooftop, and compressors may be used to operate nail guns used to install roofing materials. The
energy and emissions from the potential use of equipment and tools is not included within the
system boundaries of the BEES model.
The mass of fiber cement shingles is assumed to be 16 kg/m2 (325 Ib/square), based on 36 cm x
76 cm x 0.4 cm (14 in x 30 in x 5/32 in) size shingles. One layer of Type-30 felt underlayment is
used under the shingles. To install the shingles and underlayment, 13 galvanized steel nails per
m2 (120 nails per square) are assumed to be used for the underlayment, and 32 nails per m2 (300
nails per square) are used for the shingles. Each galvanized steel nail is assumed to weigh 0.002
kg (0.004 Ib). Installation scrap is estimated at 5 % of the installed weight and is assumed to be
landfilled.
Use
The product is assumed to have a useful life of 45 years. At replacement, it is assumed that a new
layer of felt is applied beneath the new shingles.
It is important to consider solar reflectivity differences among roof coverings of different
materials and colors when assessing the environmental and economic performance of roof
covering alternatives. "Cool" roofs reflect and emit solar radiation well, and thus stay cooler in
the sun than less reflective, less emissive materials. The cool temperature results in building-
scale cooling energy savings ranging from 2 % to 60 %.128 A much less significant rise in
building heating energy costs also occurs. BEES accounts for solar reflectivity performance in
computing energy-related LCA inventory flows and building energy costs over the 50-year use
stage for roof covering products.
For roof coverings, thermal performance differences are separately assessed for 16 U.S. cities
spread across a range of Sunbelt climate and fuel cost zones. When selecting roof covering
alternatives for use in Sunbelt climates,129 the BEES user chooses 1) the roof covering material
and color, 2) the U.S. Sunbelt climate city closest to the building location, 3) the building type
(new or existing), 4) its heating and cooling system (electric air-source heat pump or gas
furnace/central air conditioning heating and cooling systems), and 5) its duct placement
(uninsulated attic ducts or ducts in the conditioned space), so that thermal performance
128 Memorandum from Sarah Bretz/Lawrence Berkeley National Laboratory to Barbara Lippiatt/National
Institute of Standards and Technology, 12/18/98.
129 In cold climates, the amount of roof insulation is more important to thermal performance than the color of the
roof covering.
138
-------
differences may be customized to these important contributors to building energy use. Energy
use data provided to the National Institute of Standards and Technology by Lawrence Berkeley
National Laboratory (and which LBL developed for the U.S. EPA Energy Star Roof Products
program), tailored to these five parameters, are used to estimate 50-year heating and cooling
requirements per functional unit of roof covering. 13° BEES environmental performance results
account for the energy-related inventory flows resulting from these energy requirements (stored
in USEENVIR.DBF), and BEES economic performance results account for the present value
cost resulting from these energy requirements (stored in USEECON.DBF).
End of Life
When the shingles and underlayment are removed after 45 years, all materials (shingles,
underlayment, nails) are assumed to be disposed of in a landfill, and are modeled as such.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0LCA Software. 2005. The Netherlands.
Industry Contacts
Martha VanGeem, P.E., Construction Technology Laboratories, Inc. (on behalf of the Portland
Cement Association), August-October 2005
Medgar Marceau, P.E., Construction Technology Laboratories, Inc. (on behalf of the Portland
Cement Association), August-October 2005.
3.9 Roof Coatings
3.9.1 Prime Coatings Utilithane
Utilithane 1600, according to its manufacturer Prime Coatings, Inc., is a tough, flexible, abrasion
and chemical resistant polyurethane used as a protective coating and liner for a broad spectrum
of applications including concrete and steel substrates and roofs. Utilithane contains no solvents
and meets all VOC regulations.131
Utilithane is a two-component system in which 2 parts of resin are mixed with 1 part activator,
and is spray applied using plural component airless spray equipment. The product can be
applied from 0.5 mm (20 mils) to 12.7 mm (500 mils) or more in thickness during a single
application. Ultimate thickness specifications vary for each application depending on intended
use and material applied. The application modeled for BEES is a Utilithane roof coating with an
130 LBL data were developed for BEES by LBL's Sarah Bretz, based on Konopacki and Akbari, Simulated
Impact of Roof Surface Solar Absorptance, Attic, and Duct Insulation on Cooling and Heating Energy Use in
Single-Family New Residential Buildings, LBNL-41834, Lawrence Berkeley National Laboratory, Berkeley, CA,
1998, and on Parker et al., "Measured and Simulated Performance of Reflective Roofing Systems in Residential
Building," ASHRAE Transactions, SF-98-6-2, Vol. 104, 1998, p. 1.
131 See www.utilithane.com.
139
-------
average applied thickness of 2.54 mm (100 mils).
The functional unit for Utilithane is 1 ft2 of roof protection. Its density is 4.20 kg (9.25 Ib) per
gal and its coverage is approximately 148.6 m2 (1 600 ft2) per gal at one mil thickness. At this
density and coverage rate, 0.26 kg (0.58 Ib) of Utilithane are needed per ft2.
The detailed environmental performance data for this product may be viewed by opening the file
B3013A.DBF under the File/Open menu item in the BEES software.
Flow Diagram
This manufacturer considers this information confidential.
Raw Materials
This manufacturer considers this information confidential.
Manufacturing
Energy Requirements. Manufacturing involves electricity use for heating and mixing
components. Prime Coatings provided data on the mixing vessel, times, and temperatures of
mixing, and capacity of operation. The following energy requirements were modeled based on
these parameters:
Energy_Carrier kWh/ff
Electricity 0.001
[[[ 0.014 [[[
No air emissions data (except for those related to energy use) are available. Electricity and
natural gas use in a boiler are modeled based on the U.S. LCI Database.
Transportation. The resin components of the product are transported an average of 161 km (100
mi) to the manufacturing facility and the activator is transported 805 km (500 mi). Materials are
transported by diesel truck, which is modeled based on the U.S. LCI Database.
Transportation
Both the resin compound and activator are transported 1287 km (800 mi) to the site of
installation in 55 gal drums or 250 gal totes. Diesel truck is the mode of transport, and its
environmental burdens are modeled based on the U.S. LCI Database.
Installation and Use
Installation of Utilithane requires the use of a compressor to mix and spray the product and a
-------
Table 3.63:_Pritm_Coatings Vtilithane Installation Energy
Ener^_Carner_ kWh/ff
Electricity 0.004
_Diesel_fuel 0.04
End of Life
Utilithane has a useful life of over 50 years. At the end of its life, it is assumed to be disposed of
in a landfill.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Sheehan, J. et al., Life Cycle Inventory ofBiodiesel and Petroleum Diesel for Use in an Urban
Bus, NREL/SR-5 80-24089 (Washington, DC: U.S. Department of Agriculture and U.S.
Department of Energy, May 1998).
Industry Contacts
Steve Crandal, Prime Coatings (2004)
3.10 Partitions
3.10.1 Generic Gypsum
Gypsum board, also known as "drywall" or "plaster board," consists of a core of gypsum
surrounded with a paper covering. Several varieties of gypsum board products are available;
each is comprised of a specially formulated gypsum plaster mix and facing paper specifically
developed for the intended application. These gypsum board products include regular gypsum
wallboard, moisture-resistant gypsum board, and type-X fire-resistant gypsum board.
For the BEES system, 0.9 m2 (1 ft2) of 13 mm (!/2 in) gypsum wallboard, joint tape, joint
treatment compound, and wallboard nails are studied. The bulk density of wallboard is assumed
to be 769 kg/m3 (48 lb/ft3). Gypsum wallboard is assumed to be nailed to wood studs, 41 cm (16
in) on center.
The detailed environmental performance data for this product may be viewed by opening the file
C1011 A.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
141
-------
Gypsum Board
Paper
Production
Gypsum
Mining
Synthetic
Gypsum
Production
Figure 3.25: Gypsum Board System Boundaries
Raw Materials
Drywall primarily consists of gypsum that is mixed with additives and backed on both sides with
kraft paper. The following Table shows the proportions of materials used in producing drywall.
Table 3. 64:
Constituent
Gypsum
Paper
Additives
Starch
Total
Kg/m^J^
8.326(1.705)
0.981 (0.201)
0.294 (0.060)
0.196(0.040)
85%
10%
3%
2%
Data for the production of each of these raw materials comes from both the U.S. LCI Database
and SimaPro.
Manufacturing
Energy Requirements and Emissions. Gypsum board is produced using partially dehydrated or
calcinated gypsum. The gypsum is fed into a mixer where it is combined with water and other
ingredients to form a slurry or paste. The slurry is spread onto a moving belt of face paper and
then covered with a backing paper. As the materials move down the production line, the edges of
the face paper are folded over the backing paper to create one of several edge types. The board
then progresses down the production line where it is cut into specific lengths. The individual
boards are subsequently run through dryers. Once dry, the wallboard moves further down the
142
-------
line where it is trimmed to an exact length, paired with another board, bound on both ends with a
labeling tape, and stacked in a bundle. The bundles are taken into the warehouse, where they are
selected for shipment to either distributors or building sites.
The energy requirement for manufacturing is essentially natural gas used for the drying process -
the specific amount of natural gas consumed is provided in the following Table.
Table 3.65: Ener^ Reauirements_ifor_ G^P_sunt Board
Carrier
Natural Gas 19.02 (8 196)
Emissions from the production of gypsum are included in the product data for the raw materials
acquisition life-cycle stage. Emissions from manufacturing are based on U.S. EPA AP-42
emissions factors for gypsum processing. These emissions consist primarily of particulate
emissions (known as PM-10) during the cutting and sawing stage in the plant. Only the PM-10
emissions are included in the manufacturing life-cycle stage data.
Table 3.66: Emissions_ifrorn G£P_surn Board_Manu^cturing
Emissions kg/n? (g/f^}
PM-10 0.000027 (b" 00251)
Filterable Particulates 0.000036 (0.00334)
Transportation. The transportation of the gypsum, starch, and additives to the gypsum board
facility is taken into account, and assumed to require 80 km (50 mi) by truck. The paper used to
back the gypsum board is assumed to be shipped in rolls 402 km (250 mi) by truck to the plant.
Waste. Approximately 2.25 % of the gypsum board produced is lost as waste during the
manufacturing process.
Transportation
Transportation of gypsum board by heavy-duty truck to the building site is modeled as a variable
of the BEES system.
Installation
Gypsum board may be attached to wood framing, cold-formed steel framing, or existing surfaces
using nails, staples, screws, and adhesives appropriate for the application. Joints between
gypsum boards may be sealed or finished using paper or glass fiber mesh and one or more layers
of joint treatment compound. Joint treatment compound is available in ready-mixed or dry
powder form. The ready mixed variety is usually a vinyl-based, ready-to-use product that
contains limestone to provide body. Clay, mica, talc, or perlite are often used as fillers. Ethylene
glycol is used as an extender, and antibacterial and anti-fungal agents are also included. The dry
powder form of joint treatment compound is available in normal drying (dries primarily by
143
-------
evaporation) and accelerated setting (chemically setting) formulations.
Approximately 2.04 kg (4.5 Ib) of wallboard nails are used for each 92.90 m2 (1 000 ft2) of
wallboard.132 Joints are assumed to be treated with 52 mm-wide (2-1/16 in-wide) paper joint tape
and ready-mixed, all-purpose joint treatment compound. Approximately 62.6 kg (138 Ib) of joint
compound are assumed to be used for every 92.90 m2 (1 000 ft2) of wallboard.133 About 12 % of
the installation materials are assumed to go to waste, all of which is disposed of in a landfill.
Use
Gypsum board is assumed to have a useful life of 75 years, provided it is well maintained and
protected. There are no emissions from the use of gypsum board and repairs required to patch
holes or tears are not included in the product system boundaries.
End of Life
While there is some recovery of gypsum board at end of life, most of the material is disposed of
in a landfill. No recycling is included in the system boundaries.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
USG Corporation, The Gypsum Construction Handbook. (Chicago, IL: USG Corporation,
2000). Found at http://www.usg.com/resources/handbooks/ViewGCH.do.
Industry Contacts
Michael Gardiner, Gypsum Association (Nov 2005 - Jan 2006)
is:
2 USG Corporation, The Gypsum Construction Handbook. (Chicago, IL: USG Corporation, 2000).
133 Ibid.
144
-------
3.10.2 Trespa Virtuon and Athlon Panels
See documentation on all Trespa composite panels under Fabricated Toilet Partitions.
3.10.3 P&M Plastics Altree Panels
Altree panels, manufactured by P&M Plastics, Inc., are biobased composite panels composed of
wood fiber from invasive tree species, or of scrub and plastic from recycled milk bottles.
According to the manufacturer, the encapsulation of plastic in the product makes Altree less
susceptible than other types of wood composite boards to thickness swelling when exposed to
high humidity or water. The plastic also reduces the opportunity for decay from fungus, mold,
and mildew and aids in resistance to termites and other insects, rodents, and parasites.
Altree panels are used in a variety of exterior and interior applications. For BEES, Altree panels
are found in the Partitions product category.
The detailed environmental performance data for this product may be viewed by opening the file
C1011D.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
P&M Plastics Altree Panel
Truck
Transport to
Bid Site
Functional Ur
Altree Pan
' •
i
Stainless steel
bolt pro 'n
T t
Forest residues
production
Recycled
HOPE pro 'n
lit Of
els
I L
Compc
pan
Produ
i
>sit
Proces
energy
Raw material
transpor
T
Maleated HOPE Lubrican
coupling agent production
t
Colo ran
production
Figure 3.25a: P&M Plastics Altree Panel System Boundaries
Raw Materials
145
-------
Altree panels are comprised of the materials given in the table below.
Constituent M^ciss_Fractiojn^(%)_
Woody forest residues 38.3
Recycled HOPE 57.3
Maleated HDPE coupling agent 2.2
Surfactant with lubricant 2.2
Colorant 0.6
Altree panels consist of wood fiber from invasive species, which is taken whole (and includes
needles, branches, bark, and small and large woody stems) or in chips at the acquisition site.
Because the wood used is either residuals from the forest or shrubs with no other use or value,
and no planting has been done, the modeling of this input takes into account only the fuel used to
collect the material.
The modeling of recycled high density polyethylene (HDPE) is based on the energy to produce
clean flakes from milk jugs, and is calculated from an industry report to be 0.22 kWh/kg (0.36
MJ/lb) produced. Electricity is based on the U.S average grid mix and data is based on the U.S.
LCI Database.
The maleated HDPE coupling agent is assumed to be a combination of maleic anhydride and
virgin HDPE. Most of the data for maleic anhydride comes from a chemical process report
produced for the U.S. Department of Energy. HDPE data comes from the U.S. LCI Database.
For lack of other data on the specific lubricating surfactant used in Altree panels, it is modeled as
linear alkylbenzene sulphonate (LAS) based on its anionic surfactant properties. Data for LAS
comes from a European life-cycle inventory containing late 1990s data on European detergent
production. The colorant is excluded because its exact composition is unknown and it only
accounts for 0.6 % of the mass of raw materials.
Manufacturing
Energy Requirements and Emissions. At manufacturing, the forest residue is ground to a fine
fibrous state. This and the other raw materials are compounded or fed and blended into the
molten polymer. The compounded material is then pressed or shaped into an end product. These
process stages require purchased electricity and natural gas in a boiler in the following amounts.
Electricity134 4.3 MJ (1.2 kWh)
Natural gas135 0.43 MJ (0.12 kWh)
In addition to energy, 0.061 L (0.016 gal) of cooling water is used per kg of product. No data are
134 This figure is based on a purchased electricity rate of 5 MW of total yearly production and the estimated
operating time, as provided by the manufacturer.
135 This figure is based on total ft3 of natural gas purchased and total yearly production, as provided by the
manufacturer.
146
-------
available on particulates resulting from the grinding process.
Transportation. Data for the transportation of raw materials from the supplier to the
manufacturer is provided by P&M Plastics, with diesel truck as the mode of transportation.
Diesel trucking is modeled based on the U.S. LCI Database.
Transportation
Diesel truck and rail are the modes of Altree panel transport from manufacturing to use, with the
average distance traveled being 402 km (250 mi), shared equally by truck and rail. Both modes
of transport are modeled based on the U.S. LCI Database.
Use
Altree is assumed to be installed using an average of 0.0023 kg (0.0051 Ib) of stainless steel
bolts for each 0.09 m2 (1 ft2) of panel. The production of steel comes from the U.S. LCI
Database. Approximately 3 % of the panel is lost to waste during the installation process from
cutting the panels to fit the installation area.
End of Life
Altree is assumed to have a lifetime of 50 years. After year 50, the panel is removed and is
modeled as being recycled, or reused, 20 % of the time and landfilled 80 % of the time.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Climenhage, David, Recycled Plastic Lumber (Ontario, Canada, Environment and Plastics
Industry Council and Corporations Supporting Recycling, January 2003), p. 34. Found at:
http ://www. cpia. ca/epic/
BRIDGES to Sustainability, A Pilot Study of Energy Performance Levels for the U.S.
Chemical Industry, Contract # DE-AC05-OOOR22725 (Oak Ridge, TN, U.S. Department of
Energy, June 2001).
Dall'Acqua, S., et al., Life Cycle Inventories for the Production of Detergent Ingredients,
Report #244 (St. Gallen: EMPA, 1999).
Industry Contacts
John Youngquist, P&M Plastics, Inc. (November 2004)
147
-------
3.11 Fabricated Toilet Partitions, Lockers, Ceiling Finishes, Fixed Casework, Table
Tops/Counter Tops/Shelving
3.11.1 Trespa Composite Panels
Based in The Netherlands, Trespa International BV is the world's largest manufacturer of solid
composite panels. Trespa entered the U.S. market in 1991, and now produces millions of ft2 of
sheet material annually. Trespa North America's products offer an alternative to thin laminate
and epoxy-resin products. Each of Trespa's four composite panel lines has been designed for a
particular use:
1. Athlon, a panel developed for a wide range of interior applications including durable fittings;
2. Meteon, a panel developed for exterior applications such as such as facade cladding, roof
edgings, canopies & street furniture;
3. TopLabPLUS, a panel that is highly resistant to chemicals and designed for laboratory work
surface areas; and
4. Virtuon, an interior panel system that is impact, moisture, and stain resistant, thus suggested
for applications in public areas and areas where cleanliness is very important.
In October 2005, the GREENGUARD Environmental Institute awarded GREENGUARD Indoor
Air Quality Certification to Trespa's Athlon, Virtuon, and TopLabPLUS panels, which were
tested for chemical emissions performance under the GREENGUARD Standard for Low
Emitting Products.136 According to GREENGUARD, these panels can be specified with the
confidence that they will not impact the indoor air.137
For the BEES system, the functional unit for composite panels, regardless of application, is 0.09
m2(l ft2) of panel.
The detailed environmental performance data for these products may be viewed by opening the
following files under the File/Open menu item in the BEES software:
• C3 03 OB .DBF—Athlon
• B2011F.DBF—Meteon
• E2021 A.DBF— TopLabPZ US
• C3 030 A.DBF—Virtuon
Flow Diagram
The flow diagram below shows the major elements of the production of these products, as they
are currently modeled for BEES.
136 GREENGUARD Environmental Institute, "Trespa phenolic panels earn GREENGUARD Indoor Air Quality
certification," (Atlanta, Georgia, October 2005).
137 Ibid.
148
-------
Trespa Composite Panels
Functional Unit of
Trespa Panels
Figure 3.26: Trespa Composite Panels System Boundaries
Raw Materials
All Trespa panels are made in the same way - with an interior core material and a layer of
decorative facing on both sides. The core and facing materials come from different sources for
different applications, so the overall mix of raw material inputs is different for each product as
shown in the Table below.
149
-------
Constituent
Kraft paper (recycled)
Wood chips
Bisphenol-A-Tar
Formaldehyde
Other Materials
Athlon
52%
0%
18%
28%
2%
Meteon
17%
38%
17%
28%
0%
17%
38%
17%
28%
0%
Virtuon
44%
0%
15%
24%
18%
The kraft paper used in the panels is recycled, so no raw material inputs for this product
constituent are modeled, with the exception of its transport to the manufacturing site. Wood
chips come from pine. Pine wood chip production is a coproduct of timber production, whose
BEES model includes raising pine seedlings, planting, fertilizer, and harvesting. Energy use and
other life cycle data for southern pine tree production and harvesting in the Southeastern United
States are based on CORRIM data,138 which is also found in the U.S. LCI Database.
Bisphenol-A-Tar is used as a binder in the panels. Tar is a co-product of Bisphenol A
production, so a portion of the production burdens of Bisphenol A are allocated to the production
of the tar. Formaldehyde is also used as a binder in the panels, and is assigned the same
upstream production data as that for other BEES products with formaldehyde. BEES data for
formaldehyde, Bisphenol A, and the other materials in the Trespa products are derived from the
contents of the SimaPro database.
Manufacturing
Energy Requirements and Emissions. Trespa composite panel manufacturing consists of
bonding the core panel and the two decorative panels. The manufacturing process requires
natural gas, diesel oil, and electricity as energy inputs. To produce one square meter of panel,
Trespa uses 2.6 kWh (9.4 MJ) of electricity, 23.4 kWh (84.4 MJ) of natural gas, and 0.17 kWh
(0.6 MJ) of diesel oil. All energy data, including electricity, diesel equipment, and natural gas
use in boilers are modeled using the U.S. average electric grid from the U.S. LCI Database.
Transportation. Data for the transport of raw materials from the supplier to the manufacturer
are provided by Trespa, with diesel truck as the mode of transportation. Diesel trucking is
modeled based on the U.S. LCI Database.
Transportation
Trespa panels are shipped from the production facility in The Netherlands to a U.S. port - a
distance that is modeled as 10 000 km (6 214 mi) by sea. The transportation emissions allocated
to each of the four Trespa panel products are based on the overall mass of the product, as given
in the Table below. Transportation from the U.S. port of entry to the building site, by diesel
truck, is modeled as a variable in BEES.
138 Bowyer, I, et. al., Phase I Final Report: Life Cycle Environmental Performance of Renewable Building
Materials in the Context of Residential Construction. (Seattle, WA: Consortium for Research on Renewable
Industrial Materials-CORRIM, Inc./University of Washington, 2004) Found at http://www.corrim.org/reports.
150
-------
Table 3.68: Trespa Composite Panel Density
Product Mass per Applied Area Density
All poducts (10 mm or O39 in 14 (23) 1 400 (8T40)
Diesel trucking and transportation via ocean freighter are modeled based on the U.S. LCI
Database.
Installation and Use
Trespa panels are installed using stainless steel bolts. On average, 0.025 kg (0.055 Ib) of
stainless steel bolts are required to install 1 m2 (11 ft2) of composite panel. Approximately 3 %
of the panel is lost as waste during the installation process due to scrap from cutting the panels to
fit the installation area.
End of Life
Trespa panels are assumed to have a lifetime of 50 years. After year 50, the panels are removed
and about 50 % of the waste is reused in other products, while the remaining 50 % is sent to a
landfill.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
GREENGUARD Environmental Institute, "Trespa phenolic panels earn GREENGUARD
Indoor Air Quality certification," (Atlanta, Georgia, October 2005).
Bowyer, J., et. al., Phase I Final Report: Life Cycle Environmental Performance of Renewable
Building Materials in the Context of Residential Construction. (Seattle, WA: Consortium for
Research on Renewable Industrial Materials—CORRIM, Inc./University of Washington,
2004) Found at http://www.corrim.org/reports.
3.12 Wall Finishes to Interior Walls
3.12.1 Generic Latex Paint Products
Conventional paints are generally classified into two basic categories: water-based (in which the
solvent is water) and oil-based (in which the solvent is an organic liquid, usually derived from
petrochemicals). Oil-based paints are sometimes referred to as solvent-based. Paints essentially
consist of a resin or binder, pigments, and a carrier in which these are dissolved or suspended.
Once the paint is applied to a surface, the carrier evaporates, leaving behind a solid coating. In
oil-based paints the carrier is a solvent consisting of volatile organic compounds (VOC), which
can adversely affect indoor air quality and the environment. As a result, government regulations
and consumer demand are forcing continuing changes in paint formulations. These changes
have led to formulations containing more paint solids and less solvent, and a shift away from oil-
based paints to waterborne or latex paints.
151
-------
BEES considers three neutral-colored, latex-based paint alternatives for interior use: virgin latex
paint plus two types of latex paint that contain leftover household paint, or post-consumer (PC)
paint—consolidated and reprocessed. Because they do not use solvents as the primary carrier,
latex paints emit far fewer volatile organic compounds (VOC) upon application. They also do
not require solvents for cleaning of the tools and equipment after use. Water with a coalescing
agent is the carrier for latex paints. The coalescing agent is typically a glycol or glycol ether.
The binder is synthetic latex made from polyvinyl acetate and/or acrylic polymers and
copolymers. Titanium dioxide is the primary pigment used to impart hiding properties in white
or light-colored paints. A range of pigment extenders may be added. Other additives include
surfactants, defoamers, preservatives, and fungicides.
Consolidated paint facilities are often located at or near county or city recycling and Household
Hazardous Waste (HHW) facilities. These facilities generally have relatively small-scale
operations in which paint meeting a certain quality is blended and repackaged and sold or given
away to the public. In larger consolidating operations, some virgin materials are added to the
paint. Reprocessed paint is generally produced in a larger-scale facility and varies by producer
and PC paint content; reprocessed paint can contain 50 % to over 90 % PC paint.
The three latex paint alternatives are applied the same way. The surface to be painted is first
primed and then painted with two coats of paint. One coat of paint is then applied every 4 years.
In reality, the three paint options vary in quality, but for BEES they are assumed to be of the
same quality, with one gal covering 37.2 m2 (400 ft2).
The detailed environmental performance data for these products may be viewed by opening the
following files under the File/Open menu item in the BEES software:
• C3012A.DBF—Virgin Latex Paint
• C3012B.DBF—Consolidated Latex Paint
• C3012C.DBF—Reprocessed Latex Paint
Flow Diagram
The flow diagram shown below shows the major elements of the production of these products as
they are currently modeled for BEES.
152
-------
Virgin Latex Paint
Figure 3.27: Virgin Interior Latex Paint System Boundaries
Consolidated and Reprocessed Interior Latex Paint
Figure 3.28: Consolidated and Reprocessed Interior Latex Paint System Boundaries
Raw Materials
Virgin latex paint. The major virgin latex paint constituents are resins (binder), titanium dioxide
(pigment), limestone (extender), and water (thinner), which are mixed together until they form
an emulsion. The average composition of the virgin latex paint/primer system modeled in BEES
is listed in the Table below.
153
-------
Constituent
Resin
Titanium dioxide
Limestone
Water
Paint Mass
~!^H!EH!?^JL4i
25
12.5
12.5
50
Primer Mass
fraction
25
7.5
7.5
60
l^/^_
The data for titanium dioxide is 1990s European production data from the SimaPro database.
Limestone data comes from the U.S. LCI Database. The Table below displays the market shares
for the resins used for interior latex paint and primer as well as the components of each type of
resin as they are modeled in BEES. The production of the monomers used in the resins is based
on elements of the SimaPro database.
Table 3.70: Latex Paint Resin Constituents
Resin Type
Vinyl Acrylic
Polyvinyl Acrylic
Styrene Acrylic
Market
Share
(%)
25
12.5
12.5
Constituents
Vinyl Acetate
Butyl Aery late
Polyvinyl Acrylic
Styrene
Bu^l_AcryJate
Mass
Fraction
^r^L
80 to 95
5 to 20
100
50
50
Virgin latex paint is assumed to be sold in one-gal steel cans, which are included in the model.
Steel data comes from life cycle inventories submitted by the American Iron and Steel Institute
(AISI) and the International Iron and Steel Institute (IISI) and represents late 1990s worldwide
production of steel.
Consolidated paint. A recent LCA study on leftover paint waste management139 that surveyed
paint consolidation plants all over the United States found the average percentage of virgin
constituents to be approximately 1.5 %, with the remainder being leftover household paint. At
5.08 kg (11.2 Ib) per gal this amounts to 0.08 kg (0.17 Ib) of virgin additives, which are
described above. Consolidated paint is usually repackaged in 19 L (5 gal) high density
polyethylene (HDPE) plastic buckets, which are included in the BEES model. Data on HOPE
comes from American Chemistry Council 2006 data developed for submission to the U.S. LCI
Database.
Reprocessed paint. The leftover paint waste management study also surveyed paint
reprocessing plants. Based on this survey, PC paint content ranged from 55 % to 93 %, with a
weighted average of 76 %. Therefore, the quantity of virgin constituents was modeled as 24 %,
amounting to 1.24 kg (2.74 Ib) of virgin additives per gal of reprocessed paint, at an assumed
139 Franklin Associates and Four Elements Consulting, LLC, "Life Cycle Assessment Results for Six "Pure"
Methods for Managing Leftover Paint. Draft Report" (Paint Product Stewardship Initiative, 2006). For more
information, go to http://www.productstewardship.us.
154
-------
density of 1.34 kg/L (11.2 Ib/gal). These additives are described under the virgin latex paint raw
materials section above. Reprocessed paint is packaged in both 19 L (5 gal) HDPE plastic
buckets and 3.8 L (1 gal) steel containers; the BEES model assumes half the reprocessed paint is
packaged in each option.
Manufacturing
Paint manufacture essentially consists of combining the ingredients, less some of the solvent, in
a steel mixing vessel. In some cases the mixing is followed by a grinding operation to break up
the dry ingredients, which tend to clump during mixing. Then, additional solvents or other
liquids are added to achieve final viscosity, and supplemental tinting is added. Finally, the paint
is strained, put into cans, and packaged for shipping.
Virgin latex paint. The blending energy for virgin latex paint and the paint primer is assumed to
be 4.5 MJ (1.25 kWh) of purchased electricity per gal of paint blended and 7.0 MJ (1.94 kWh) of
additional energy per gal.140 In the absence of data on the source of the additional energy
required, it is assumed to be natural gas. Emissions associated with paint and paint primer
manufacturing, such as particulates to the air, are based on U.S. EPA AP-42 emission factors.
Truck transportation of raw materials to the paint manufacturing site is assumed to average 402
km (250 mi) for limestone, 2400 km (1500 mi) for titanium dioxide, and 80 km (50 mi) for the
resins.
Consolidated latex paint. Before PC paint undergoes consolidation, it is sorted from solvent
based paints, contaminated paint, and other HHW materials that come to a HHW facility. Once
the paint in good condition is separated from other types of paint and HHW, the paint cans are
opened manually or electrically and paint is poured into a mixing vessel. The cans are
sometimes crushed using electrical equipment. Water is often used to clean facilities, as are
absorbents to soak up paint from the floor. Waste is minimized as often the emptied containers
are recycled. The following Table provides consolidation plant sorting inputs and outputs.
140 Based on the amount of purchased electricity reported in U.S. Department of Commerce, "2002 Census
Report: Paint and Coating Manufacturing 2002," based on 1.3 billion gallons of all paints and coatings produced in
2002.
155
-------
Table 3. 71 : Consolidated Paint Sorting Data
Inputs
Water used
Absorbent used to absorb paint
on floor
Electricity
Natural gas process fuel
Diesel fuel (mobile equipment)
Natural gas (mobile equipment)
Propane (mobile equipment)
Gasoline (mobile equipment)
used oil
Outputs
Waste
L/L (gal/gal) 0.22 (0.22)
kg/L (Ib/gal)
J/L (kwh/gal)
m3/L (ft3/gal)
L/L (gal/gal)
L/L (gal/gal)
L/L (gal/gal)
L/L (gal/gal)
L/L (gal/gal)
0.0002 (0.002)
310227(0.327)
0.0001(0.010)
0.0009(0.001)
0.0003 (0.0003)
0.005 (0.005)
0.0002 (0.0002)
0.001(0.001)
kg/L(lb/gal) 0.102(0.850)
Next, the paint is blended and repackaged.
process energy and water requirements.
The following Table provides the consolidation
Flow
Water used
Electricity
Natural gas process fuel
Diesel fuel (mobile equipment)
Units
L/L (gal/gal)
J/L (kwh/gal)
m3/L (ft3/gal)
L/L (gal/gal)
L/L (gal/gal)
Amount
0.07 (0.07)
55 092 (0.058)
0.00001 (0.002)
0.002 (0.002)
0.007 (0.007)
The absorbent used to soak up paint from the facility floor is reported as cat litter, which is
modeled as clay using the SimaPro database. All data on energy use and combustion in mobile
equipment and boilers comes from the U.S. LCI Database.
The leftover paint waste management study found that about 60 % of the time, paint comes to a
consolidation plant by truck from a HHW facility or a municipal solid waste transfer station.
The remaining incoming paint comes directly from households via passenger vehicle. Based on
the surveys, truck transportation is on average 161 km (100 mi) and car transport is on average
15 km (9.4 mi). The passenger vehicle mileage has been allocated to one-fourth its amount to
account for the mass of other HHW drop-off items likely transported in the car plus driving for
other errands during the same trip. The passenger vehicle is modeled as 50 % gasoline-powered
car and 50 % sport utility vehicle, and gasoline usage and emissions data come from an EPA
study on passenger vehicles.141 Truck transportation data comes from the U.S. LCI Database.
Reprocessed latex paint. As with consolidated paint, before paint is reprocessed it must be
141 National Vehicle and Fuel Emissions Laboratory, "Annual Emissions and Fuel Consumption for an
"Average" Passenger Caf and Annual Emissions and Fuel Consumption for an "Average" Light Truck (U.S.
Environmental Protection Agency: EPA420-F-97-037, April 1997).
156
-------
sorted from other incoming materials. Once the PC latex paint appropriate for reprocessing is
sorted from other paints and materials, it is blended with virgin materials and packaged for sale.
The following tables provide the inputs and outputs from sorting and reprocessing.
S^JtepmcessedJ*^^
Flow Quantity per L
Inputs:
Water used 0.565 L (0.565 gal)
Electricity 0.425 MJ (0.447 kWh)
Propane (mobile equipment) 0.0023 L (0.0023 gal)
Gasoline (mobile equipment) 0.0009 L (0.0009 gal)
Outputs:
0.0083 kg (0.07 Ib)
Paint reprocessing facilities mostly receive leftover paint via truck from collection sites
including HHW facilities. Because there are fewer reprocessing facilities, trucks travel on
average a greater distance than to consolidation facilities; this distance is about 885 km (550 mi)
according to the leftover paint study.
Transportation
Transportation of virgin and reprocessed latex paint from the manufacturing facility to the
building site via heavy-duty truck is modeled as a variable of the BEES system. Transportation
of the consolidated paint, also a BEES variable, is accomplished by gasoline-powered car and
sport utility vehicle, typically traveling a much shorter distance due to the high number of local
paint consolidation facilities and markets.
Installation
At the beginning of the 50-year BEES use period, one coat of primer is applied under the two
coats of paint. The raw materials section above provides the material constituents for primer.
Use
Every four years, the wall is assumed to be painted over with one additional coat, amounting to
12 additional coats over the 50-year use period. As with all BEES products, these
"replacements" are accounted for in the model. All three paint options are assumed to have a
VOC content of 150 g (5.29 oz) per liter and to release 20.5 g (0.05 Ib) VOC per functional unit
over 50 years.
End of Life
At end of life, all the paint goes into the landfill with the wall on which it is applied.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database . 2005.
Golden, CO. Found at: http://www.nrel . gov/lci/database.
PRe Consultants: SimaPro 6.0LCA Software. 2005. The Netherlands.
157
-------
Industry Contacts
David Darling, National Paint & Coating Association (2005)
3.13 Floor Coverings
3.13.1 Generic Ceramic Tile With Recycled Glass
Ceramic tile flooring consists of clay, or a mixture of clay and other ceramic materials, which is
baked in a kiln to a permanent hardness. To improve environmental performance, recycled
windshield glass is often added to the ceramic mix.
For the BEES system, a 50-year ceramic tile with 75 % recycled windshield glass content,
installed using a latex-cement mortar, is studied. Each tile is 15 cm x 15 cm x 1.3 cm (6 in x 6 in
x 1/2 in) and weighs 632.4 g (22.31 oz).
The detailed environmental performance data for this product may be viewed by opening the file
C3020A.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
Styrene
Production
Butadiene
Reduction
Cera
A
Styrene
Production
t
mic Tiles with Recycled Glass
Truck
Transport to
Bldg Site
i
Functional Unit of
Recycled Glass
i,
L A
Mortar
Reduction
" t
1
Portland
Cement
Reduction
l
Sand Mining
Clay Tile ^ Rocess
Reduction " Energy
'' A ' •
Raw Material
Transport
Recycled
Glass Clay Mining
Reduction
Figure 3.29: Ceramic Tile System Boundaries
Raw Materials
Clay and recycled glass are the primary constituents of the ceramic tile. The mass of each raw
material is provided in the Table below.
158
-------
Table 3. 74: Ceramic Tile Constituents
Constituent
Clay
Recycled Glass
Mass
Fraction
25%
75%
kg/tile
(oz/tile)
0.1581
(5.577)
0.4743
n £> TI\
kg/m2
6.807
(22.31)
20.42
(£>£> cm
The environmental impacts for the production of clay are based on surrogate data in the SimaPro
database. Burdens associated with glass production are allocated to the application for which the
glass is initially produced (vehicle windshields), so the only burdens from recycled glass
production are those associated with the collection and reprocessing of windshields.
The ceramic tiles are installed using a latex/mortar blend. The constituents of the latex/mortar
blend are provided in the Table below.
, 3. 75: LatexMortar_Blend_ Constituents
Constituent Mass_ Fraction
Mortar 69.6 %
Portland Cement 17%
Sand 83 %
St^£ene-But£diene Latex 30.4 %
Manufacturing
Energy Requirements and Emissions. The energy requirements for the drying and firing
processes of ceramic tile production are listed in the Table below.
Table 3. 76: Energy Requirements £or_ Ceramic^ Til£ Manufacturing
Energy Carrier
Coal
Natural Gas
Fuel Oil
Wood
Total
Contribution
9.6 %
71.9%
7.8 %
10.8 %
100 %
(Btu/lb)
0.402 (173)
3.013(1295)
0.327 (140)
0.448 (193)
4.19 (1 801)
Emissions for ceramic tile firing and drying are based on U.S. EPA AP-42 data for emissions
from the combustion of the specific fuel types.
Transportation. Transportation of the recycled glass to the tile facility is taken into account as
402 km (250 mi) by truck. The clay used to make the tiles is assumed to be shipped by truck 80
km (50 mi).
Waste. The manufacturing process generates no waste materials as all materials are reutilized in
159
-------
the plant.
Transportation
The distance for mortar transport to the end user is assumed to be 241 km (150 mi) by truck.
Transportation of tiles by diesel truck to the building site is modeled as a variable of the BEES
system.
Installation
Installing ceramic tile requires a layer of latex/mortar approximately 1.3 cm (l/2 in.) thick, which
is equivalent to 0.567 kg (1.25 Ib) per ft2.142 The relatively small amount of latex/mortar used
between the tiles is not included. Installation of tile and mortar is assumed to be a manual
process, so no there are no emissions or energy inputs. About 5 % of the installation materials
are assumed to go to waste, all of which is disposed of in a landfill.
Use
Ceramic tile with recycled glass is assumed to have a useful life of 50 years. Maintenance of the
tile floor during this period - e.g., cleaning, polishing - is not included within the system
boundaries.
End of Life
All of the ceramic tile and latex/mortar are assumed to be disposed of in a landfill at end of life.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0LCA Software. 2005. The Netherlands.
Industry Contacts
National Tile Contractors Association (2005)
3.13.2 Generic Linoleum Flooring
Linoleum is a resilient, organic-based floor covering consisting of a backing covered with a thick
wearing surface. For the BEES system, 2.5 mm (0.098 in) sheet linoleum manufactured in
Europe, with a jute backing and a polyurethane-acrylic finish coat, is studied. An acrylate
copolymer adhesive is included for installation.
The detailed environmental performance data for this product may be viewed by opening the file
C3020B.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below presents the major elements of the production of this product as it is
currently modeled for BEES.
142 Average application rate at 0.5 in thickness reported at http://www.texascement.com/mortarcalc.html and
http://www.c-cure.com/servref/covcalc/impmort/fimp.htm.
160
-------
Linoleum
Figure 3.30: Linoleum Flooring System Boundaries
Raw Materials
The following Table lists the constituents of linoleum and their proportions. The data comes
from a European study on the life cycle of flooring materials.143 One square meter of 2.5 mm
(0.098 in) linoleum weighs approximately 2.9 kg (6.4 Ib).
1 Asa, I, et al.(Sweden: Chalmers University of Technology, 1995).
161
-------
Table 3.77: Linoleum Constituents
Linseed oil
Pine rosin/tall oil
Limestone
Wood flour
Cork flour
TiC>2 (pigment)
Jute (backing)
^^rylicjacquer^^^
23.3 %
7.8 %
17.7 %
30.5 %
5.0%
4.4 %
10.9%
0.35 %
670 (2.2)
224 (0.7)
509(1.7)
877 (2.9)
144 (0.5)
127 (0.4)
313(1.0)
__IOJUC)3]__
The cultivation of linseed is based on a modified version of wheat production from the U.S. LCI
Database (for lack of other available data), and inputs are presented below.
Nitrogen Fertilizer
Phosphorus Fertilizer
Potassium Fertilizer
Pesticides (active compounds,
with 20 % lost to the
31 (28)
20 (17)
25 (22)
0.7 (0.7)
To harvest the linseed, it is assumed that a diesel tractor is used, requiring approximately 0.61
MJ of diesel fuel per kg (263 Btu/lb) of linseed harvested. The yield of linseed is 1 038 kg per
hectare (420 Ib/acre). Energy requirements for linseed oil production include fuel oil and steam,
and are allocated on an economic basis between linseed oil (87%) and linseed cake (13 %).
Allocation is necessary because linseed cake is a co-product of linseed oil production, so its
production impacts should not be included in the BEES model for linoleum flooring. The
emissions associated with linseed oil production are allocated on the same economic basis. The
production of the fertilizers and pesticides is based on elements of the SimaPro database.
The production of tall oil is based on European data for kraft pulping, with inventory flows
allocated between kraft pulp and its coproduct, tall oil.144 The production of limestone comes
from the U.S. LCI Database. Wood flour is sawdust produced as a coproduct of wood
processing, and its production is based on the U.S. LCI Database. Cork flour is a coproduct of
wine cork production. Cork tree cultivation is not included, but energy requirements for the
processing of the cork is included as shown in the Table below.
Table 3.79: Electricity Inputs for Cork Flour Production
Federation Europeenne des Fabricants de Carton Ondule (FEFCO), 2003. Found at:
http://www.fefco.org/fileadmin/Fefco/pdfs/Technical_PDF/Corrected_database_2003.pdf.
162
-------
^CorkProduct
Cork Bark
0.06 (26)
Production of the pigments used is based on the European production of titanium dioxide, from
the SimaPro database. Linoleum backing, jute, is mostly grown in India, Bangladesh, Thailand,
and China. Jute is predominantly rain-fed, requires little fertilizer and pesticides, and cultivation
is generally done by manual labor. Data for the production of acrylic lacquer materials is based
on elements of the SimaPro database.
Manufacturing
Energy Requirements. Producing linoleum requires electricity and natural gas; the following
Table lists the energy requirements for linoleum production.145
Table 3.80:_Ejiergj_Rea^
Electricity
Natural Gas
2 (859.8)
Emissions. Since most linoleum manufacturing takes place in Europe, it is assumed to be a
European product in the BEES model. European linoleum manufacturing results in the following
air emissions in addition to those from energy use.
Emissiojn
Volatile Organic Compounds
(VOC)
Solvents
0.94(0.015)
j^3JpJ)04}_
Transportation. Data for linoleum raw material transport from point of origin to a European
manufacturing location is shown in the Table below.U6
145 Data is based on an average of public data and manufacturer-specific information.
146 Asa, J., et. al., Life-Cycle Assessment of 'Flooring Mater/'afe(Sweden: Chalmers University of Technology,
1995).
163
-------
Table 3.82: Linoleum Raw Materials Transportation
Raw Material
Linseed oil
Pine rosin/tall oil
Limestone
Wood flour
Cork flour
TiO2 (pigment)
Jute (backing)
Km (mi)
4 350 (2 703)
1,500 (932)
2 000 (1 243)
800 (497)
600 (373)
2 000 (1 243)
500(311)
10 000 (6 214)
JJOOJUIL
Mode
Ocean Freighter
Train
Ocean Freighter
Train
Train
Ocean Freighter
Diesel Truck
Ocean Freighter
Diesel Truck
Transport of the finished product from Europe to the United States is included in the model as
part of the manufacturing process.
Waste. Most process waste is recycled at the plant and the remainder is sent to a landfill for
disposal. For this model, 3 % of process input materials are assumed to go to a landfill.
Transportation
Transportation of linoleum by heavy-duty truck from the U.S. distribution facility to the building
site is modeled as a variable of the BEES system Transportation data is based on the U.S. LCI
Database.
Installation
For optimal adhesion, an acrylate copolymer adhesive is applied to a subfloor or other surface at
a thickness of 0.29 mm and mass of 290 g/m2. Usually linoleum seams are sealed against
moisture by welding with a weld rod. This minimal amount of energy is not accounted for in the
model.
Installation waste is assumed to be 5 % of the installed weight. In the United States, and in
BEES, this waste is assumed to be sent to a landfill for disposal. (In Europe, this waste would go
into incineration, which would generate 18.3 MJ/kg (2.31 kWh/lb) energy.)
Use
Linoleum is known for its durability. Through evaluation of actual lifetime data, is has been
determined that linoleum has a useful life of 30 years.147 As with all BEES products, the life
cycle environmental impacts from this replacement during the 50-year use phase are included in
the life cycle inventory data. Volatile organic compound (VOC) off-gassing from the adhesive is
included in the BEES modeling.
End of Life
At end of life, it is assumed that linoleum is disposed of in a landfill.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
147 Federal Association of the Sworn Experts for Room and Equipment e.V., Guide to the Inquiry of Time Values
and Decreases in Value of Floor Coverings(Bom\, Germany: Federal Association of the Sworn Experts for Room
and Equipment e.V.)
164
-------
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Asa, J., et. al., Life-Cycle Assessment of'FlooringMaterials, (Sweden: Chalmers University of
Technology, 1995).
Federation Europeenne des Fabricants de Carton Ondule (FEFCO), European Database for
Corrugated Board Life Cycle Studies, 2003. Found at:
http://www.fefco.Org/fileadmin/F efco/pdfs/Technical_PDF/Corrected_database_2003.pdf
Federal Association of the Sworn Experts for Room and Equipment e.V., Guide to the Inquiry
of Time Values and Decreases in Value of Floor Coverings, (Bonn, Germany: Federal
Association of the Sworn Experts for Room and Equipment e.V.).
Industry Contacts
Jennifer Gaalswyk, Armstrong Corporation (Sept 2005 - Jan 2006)
3.13.3 Generic Vinyl Composition Tile
Vinyl composition tile (VCT) is a resilient floor covering. Relative to the other types of vinyl
flooring (vinyl sheet flooring and vinyl tile), VCT contains a high proportion of inorganic filler.
The tile size modeled in BEES is 30 cm x 30 cm x 0.3 cm (12 in x 12 in x 1/8 in), with a weight
of about 0.613 kg (1.35 Ib).
The detailed environmental performance data for this product may be viewed by opening the file
C3020C.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
165
-------
Vinyl Composition Tile
Truck Functional Unit of
Bldg Site Tile
ji j.
End-of-Life
Vinyl
Styrene f Styrene-Butadiene compo'ition «
Production ' Production T,le Roduction '
A
Process
Energy
A
A , i, A
Butadiene Raw ^terial ^^f^
Production Transport Vinyl Chtorrie
r Production
Acrylic
Lacquer
Production
Plasticizer Limestone
Production Production
t ,
i , A " j,
Bhylene Acetic Acid
Production Production
Oxygen
Production
Chlorine
Production
Figure 3.31: Vinyl Composition Tile System Boundaries
Raw Materials
The average makeup of vinyl composition tile is limestone, plasticizer, and a copolymer of vinyl
chloride (95 %) and vinyl acetate (5 %). A layer of styrene-butadiene adhesive is used during
installation.
The Table below lists the composition by weight of 30 cm x 30 cm x 0.3 cm (12 in x 12 in x
1/8 in) VCT. A finish coat of acrylic latex is applied to the tile at manufacture. The thickness of
the finish coat is assumed to be 0.005 mm (0.2 mils). The production of these raw materials, and
the styrene-butadiene adhesive, is based on the SimaPro database, the U.S. LCI Database, and
American Chemistry Council 2006 data developed for submission to the U.S. LCI Database.
166
-------
Constituent
Limestone
Vinyl resins: 5 % vinyl
acetate / 95 % vinyl
chloride
Plasticizer: 60 % BBP
(butyl benzyl phthalate)
/ 40 % DINP
Mass
_J*$^^
5.54(1.14)
0.797(0.163)
0.269 (0.055)
Mass
__.,F>acrio«j[%j|_
84
12
4
Internal recycling is quite common, with at least 99 % of the raw materials initially used in the
manufacturing process being ultimately used in the finished product. Typically, all scrap and
rejected materials are reused in the manufacturing process for VCT. In fact, the amount of
recycled content from tile processing can range from 12 % to 50 % of a finished tile.
It is difficult to provide a representative number for tile recycled content from sources external to
the plant, due to multiple manufacturing sites and the lack of a constant supply of both post-
industrial and postconsumer polyvinyl chloride (PVC). The majority of the recycled materials
used are post-industrial, and a conservative recycled content number from external sources is
1 % by weight of the tile.
Manufacturing
Energy Requirements and Emissions. Energy requirements for the manufacturing processes
(mixing, folding/calendaring, finish coating, and die cutting) are listed in the Table below.
Table 3.84: ^we^^_^££^£^f^^£_^sll^££^!^£Zl^ Manufacturing
Electricity 1.36(585)
Emissions associated with the manufacturing process arise from the combustion of natural gas
and are modeled using the U.S. LCI Database.
Transportation. VCT producers are located throughout the country. The bulk of the product
weight is limestone, a readily available and plentiful filler typically located in close proximity to
manufacturing sites. The raw materials used in the manufacture of the tile are all assumed to be
transported to the production facility via diesel truck over a distance of 402 km (250 mi).
Transportation of adhesive to the end user is assumed to be 241 km (150 mi) via diesel truck.
Waste. Typically, less than 1 % waste is generated from the production of VCT. This waste is
167
-------
usually comprised of granulated VCT and VCT dust and is disposed of in a landfill.
Transportation
Transportation of vinyl composition tile by heavy-duty truck to the building site is modeled as a
variable of the BEES system.
Installation
A layer of styrene-butadiene adhesive is used during installation. The thickness of the adhesive
is 0.08 cm (1/32 in) at application. Approximately 0.0133 kg (0.0294 Ib) of adhesive is applied
per ft2 of vinyl composition tile. The adhesive is applied wet, and a loss in volume arises due to
evaporation of the water in the adhesive as it dries. Adhesives are typically water-based and thus
few volatiles are emitted. Installation of vinyl composition tile is primarily a manual process, so
no energy use is modeled for the installation phase.
Installation scrap varies depending on the job size. It is estimated that, on average, installation
scrap for a commercial job is 2 % to 3 %. Scrap is sent to landfill.
Use
Vinyl composition floor tile is most commonly used in applications such as school cafeterias and
classrooms, where there is relatively little exposure to abrasion from tracked-in grit and dirt.
Based on historical observations, it is estimated that VCT in such applications lasts an average of
40 years before it is replaced due to wear. In extremely heavy traffic areas (which are normally
much smaller in area), such as entryways in a school, the tile has a shorter life expectancy.
Because of differing VCT manufacturers' maintenance recommendations, there is not a single
industry standard for maintenance of the product over its lifetime. Typically, VCT is stripped
and polished annually. Many of the acrylic finishes used after the floor is installed consist of the
same general materials as the factory-applied finishes. The equipment used to maintain the floor
depends on the maintenance system selected by the building owner, often based on the desired
overall appearance. Electric- or propane-powered floor machines may be used for stripping,
polishing, and buffing. Frequency of refmishing, and types and quantities of stripping and
polishing chemicals used each time, depend on the maintenance programs developed by
individual building owners. Today, low-volatile organic compound (VOC) or no-VOC
maintenance products are available for maintaining VCT floors. VOC off-gassing from the tile
and adhesive at each installation are included in the BEES modeling.
End of Life
At end of life, the VCT and adhesive are assumed to be disposed of in a landfill.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0LCA Software. 2005. The Netherlands.
168
-------
Industry Contacts
William Freeman, Resilient Floor Covering Institute, (September-November 2005)
3.13.4 Generic Composite Marble Tile
Composite marble tile is a type of composition flooring. It is a mixture of polyester resin and
matrix filler, colored for a marble effect, that is poured into a mold to form tiles. The mold is
then vibrated to release air and level the matrix. After curing and shrinkage the tile is removed
from the mold, trimmed, and polished if necessary.
For the BEES system, a 30 cm x 30 cm x 0.95 cm (12 in x 12 in x 3/8 in) tile, installed using a
latex-cement mortar, is studied. The detailed environmental performance data for this product
may be viewed by opening the file C3020D.DBF under the File/Open menu item in the BEES
software.
Flow Diagram
The following flow diagram shows the major elements of the production of composite marble
tile, as currently modeled in BEES.
Composite Marble Tile
Polyester
Production
Styrene
Production
Figure 3.32: Composite Marble Tile System Boundaries
169
-------
Raw Materials
The Table below gives the constituents included in the marble matrix and their proportions. It is
assumed that 3 % of the material is lost at manufacture from the trimming process.
Table 3.85: Composite Marble Tile Constituents
„ . Mass Fraction
Constituent ,0/.
Filler 78.25
Resin 20.01
Pigment (TiO2) 1.50
Catalyst (MEKP) 0.24
The resin percentage given above is a weighted average, based on data from four sources ranging
from 19 % to 26 % resin content. The remainder of the matrix is composed of filler, pigment,
and catalyst. Since calcium carbonate is the typical filler used for U.S. composite marble tile
production, it is the assumed filler material in the BEES model. The filler is composed of coarse
and fine particles in a combination of two parts coarse to one part fine. Filler production
involves the mining and grinding of calcium carbonate. The resin used in the matrix is an
unsaturated polyester resin cross-linked with styrene monomer. The styrene content can range
from 35 % to 55 %. An average value of 45 % is used for the model.
The main catalyst used in the United States for the marble matrix is Methyl Ethyl Ketone
Peroxide (MEKP). This catalyst is used as a solvent in the mixture of resin and filler, so is
consumed in the process; however, approximately 1 % of the MEKP catalyst is composed of
unreacted MEK, which is assumed to be released during the reaction. The amount of catalyst is
assumed to be about 1 % of the resin content, or 0.24 % of the total marble matrix. Due to a lack
of public data on MEKP production, and the small mass fraction of the component, MEKP
production is not included within the system boundaries.
A colorant may be used if necessary. The quantity depends on the color required. The colorant
is usually added to the mixture before all the filler has been mixed. For the BEES study,
titanium dioxide at 1.5 % is assumed.
Composite marble tiles are installed using a latex/mortar blend. The constituents of the
latex/mortar blend are provided in the Table below.
Table 3. 86: Latex/Mortar Blend Constituents
Constituent Mass Fraction
Portland Cement 38
Sand 22
40
170
-------
Manufacturing
Energy Requirements and Emissions. Electricity is the only energy source involved in
producing and casting the resin-filler mixture for composite marble tile. The tile is cured at
room temperature. The Table below shows electricity use for composite marble tile
manufacturing.
Table 3.87: Energy Requirements for Composite Marble Tile Manufacturing
Energy Carrier
Electricity 0.047 (20.3)
The chief emissions from composite marble tile manufacturing are fugitive styrene and MEK air
emissions. The styrene emissions come from the resin constituent and are assumed to be 2 % of
the resin input. The MEK emissions come from the 1 % un-reacted MEK in the catalyst blend.
Emissions of styrene from the matrix are assumed to be 0.129 kg/m2 (0.026 lb/ft2), and MEK
emissions 0.00086 kg/ m2 (0.00018 lb/ft2).
Transportation. All product raw materials are assumed to be transported 402 km (250 mi) by
truck. For the mortar raw materials, the portland cement and sand are assumed to be transported
48 km (30 mi) by truck to the packaging plant, and the latex raw materials are assumed to be
transported 161 km (100 mi) to the production facilities.
Transportation
Shipping the cement, sand, and latex to the end user is assumed to cover 322 km (200 mi) via
diesel truck. Transportation of tiles by diesel truck to the building site is modeled as a variable
of the BEES system.
Installation
Installing composite marble tile requires a sub-floor of a compatible type, such as concrete. A
layer of latex/mortar approximately 1.3 cm (1A> in) thick is used, which is equivalent to
17.96 kg/m2 (3.563 lb/ft2). Installation of tile and mortar is assumed to be primarily a manual
process, so there are no emissions or energy inputs. About 5 % of the installation materials are
assumed to go to waste, all of which is disposed of in a landfill.
Use
With general maintenance, properly installed composite marble tile will have a useful life of 75
years. Maintenance - such as cleaning and sealing of the tile - is not included within the
boundaries of the BEES model.
End of Life
At end of life, it is assumed that the composite marble tile and the latex/mortar used for
installation are disposed of in a landfill.
171
-------
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0LCA Software. 2005. The Netherlands.
Industry Contacts
No industry contacts were found that were able to provide industry data.
3.13.5 Generic Terrazzo
Terrazzo is a type of composition flooring. It consists of a mix of marble, granite, onyx, or glass
chips in portland cement, modified portland cement, or resinous matrix that is poured, cured,
ground, and polished.
BEES evaluates an epoxy, or resinous, terrazzo containing a high proportion of inorganic filler
(principally marble dust and chips), a pigment for aesthetic purposes, and epoxy resin. The
materials are mixed and installed directly on site and, when dry, are polished. The epoxy
terrazzo is 9.5 mm (3/8 in) thick.
The detailed environmental performance data for this product may be viewed by opening the file
C3020E.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
172
-------
Terrazzo Flooring
Epoxy Resin
(Part A)
Production
Epoxy
Hardener
(Part B)
Production
Figure 3.33: Terrazzo Flooring System Boundaries
Raw Materials
The Table below lists the constituents of epoxy terrazzo and their proportions.
Table 3.88: Terrazzo Flooring Constituents
Terrazzo Constituents
Mass Fraction (%)
Marble dust and chips
Epoxy resin
Pigment (titanium dioxide)
77
22
1
The term "marble" refers to all calcareous rocks capable of taking a polish (e.g., onyx, travertine,
and some serpentine rocks). Marble is quarried, selected to avoid off-color or contaminated
material, crushed, washed, and sized to yield marble chips for Terrazzo.148 Note that because
marble dust is assumed to be a coproduct rather than a waste byproduct of marble production, a
portion of the burdens of marble quarrying is allocated to marble dust production.
Typical amounts of raw materials used are as follows: 1.5 kg (3.3 Ib) of marble dust and 0.23 kg
(0.51 Ib) of marble chips per 0.09 m2 (1 ft2); 3.8 L (1 gal) of epoxy resin per 0.8 m2 (8.5 ft2); and,
depending on customer selection, from 1 % to 15 % pigment content. The density of epoxy resin
is approximately 1.1 kg/L (9.3 Ib/gal).
Manufacturing
Energy Requirements and Emissions. Terrazzo is "manufactured" at the site of installation.
148 National Terrazzo and Mosaic Association, Inc. (NMTA) website, http://www.ntma.com; Phone conversation
with NMTA representative February 2006.
173
-------
The energy requirements for the on-site process include mixing the primer, mixing the terrazzo,
grinding the surface (occurs before and after grouting), controlling the dust from grinding,
mixing grout, and polishing the floor.
The only energy data available are for mixing the terrazzo, which is assumed to require a
5.97 kW (8 hp) gasoline-powered mixer running for 5 minutes.
Table 3.89:^ner^^e^irements far
Gasoline 0.003(1.17)
Transportation. The terrazzo constituents are assumed to be transported 402 km (250 mi) by
diesel truck to the terrazzo supplier.
Waste. Approximately 1 % of the materials used to make the terrazzo are wasted during
manufacturing. This waste is assumed to be disposed of in a landfill.
Transportation
Transportation of terrazzo flooring by heavy-duty truck to the building site is modeled as a
variable of the BEES system.
Installation
Installing epoxy terrazzo requires a sub-floor of a compatible type, such as cement board,
exterior grade plywood, concrete block, concrete, or cement plaster. Most systems adhere to
concrete slabs.
^
Divider Strips (Zinc) 54.4
Epoxy Resin 34.3
Acrylic Sealer 11.3
To prevent the terrazzo from cracking, dividers are placed precisely above any concrete joints.
Back-to-back "L" strip dividers are recommended for construction joints. Standard dividers are
a 9.5 mm (3/8 in) wide, 16 gauge white zinc alloy, and weigh approximately 0.177 kg/m (0.119
Ib/ft). A 10 cm (4 in) thick concrete slab should have concrete joints at a maximum spacing of
3.7 m (12 ft); therefore, 29 m (96 ft) of divider are required for every 13.4 m2 (144 ft2).
Manufacturer specifications suggest bonding the divider strips to the floor using 100 % solid
epoxy resin. The BEES model does not account for the bonding material; the amount is assumed
to be negligible.
Prior to applying the epoxy terrazzo, the sub-floor must be primed. The primer is made by
mixing the epoxy resin components at a lower ratio than that used for the epoxy terrazzo.
174
-------
Typical coverage is approximately 18.6 m2 to 23.2 m2 (200 ft2 to 250 ft2) per blended gal of
primer.
After the terrazzo mixture has been applied and the surface has been grinded, the surface is
grouted to fill and seal any voids. The grout is made by mixing the epoxy resin components in
the same ratio used in the epoxy terrazzo. Typical coverage is approximately 46.5 m2to 65.0 m2
(500 ft2 to 700 ft2) per blended gal of grout.
After the floor has been grouted and polished, two coats of acrylic sealer are applied at an
approximate thickness of one to two mils. Typical coverage for a single coat is approximately
74.3 m2to 92.9 m2 (800 ft2 to 1 000 ft2) per gal of sealer.
Use
With general maintenance, a properly installed terrazzo floor will have a useful life of 75 years.
Maintenance - such as cleaning and sealing of the tile - is not included within the boundaries of
the BEES model.
End of Life
At end of life, it is assumed that the terrazzo and any installation materials will be disposed of in
a landfill.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0LCA Software. 2005. The Netherlands.
Industry Contacts
The National Terrazzo and Mosaic Association, Inc. (December 2005 - February 2006)
3.13.6 Generic Nylon Carpet
For the BEES analysis, nylon carpet with an 11-year life (broadloom) or 15-year life (tile) is
studied. The mass for 0.09 m2 (1 ft2) of broadloom carpet is approximately 2.2 kg/m2 (0.45
lb/ft2), while the mass for 0.09 m2 (1 ft2) of carpet tile is approximately 4.8 kg/m2 (0.98 lb/ft2).
Four different product combinations are included in the BEES database. These combinations are
listed below, along with their corresponding environmental performance data file names. Data
files may be viewed by opening them under the File/Open menu item in the BEES software.
• C3020F.DBF—Nylon Carpet Tile with Traditional Glue
• C3020I.DBF—Nylon Carpet Tile with Low-VOC Glue
• C3020L.DBF—Nylon Broadloom Carpet with Traditional Glue
• C3020O.DBF—Nylon Broadloom Carpet with Low-VOC Glue
175
-------
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
Nylon Broadloom Carpet Manufacturing
Polypropylene
Production
Styrene
Butadiene
Production
Figure 3.34: Nylon Broadloom Carpet System Boundaries
Nylon Carpet Tile Manufacturing
Figure 3.35: Nylon Carpet Tile System Boundaries
176
-------
Raw Materials
Nylon carpeting consists of a mix of materials that make up the face and the backing of the
product. The composition of broadloom carpet and carpet tiles differs significantly;
specifications are provided in the following Table.
Constituent
Broadloom
Face Fiber
Backing
Table 3.91: Nylor^Car^etConstitiients
Material g/m2 (oz/ft2)
Nylon 6,6
Polypropylene
Styrene butadiene latex
Limestone (CaCOs) filler
Stainblocker
Other additives
1 029(3.37)
227 (0.74)
263 (0.86)
909 (2.98)
0.24(0.001)
Tile
Face Fiber
Primary
Backing
Precoat
Fiberglass
Backing
Nylon 6,6
Polyester (PET) woven
EVA latex
Limestone (CaCOs) filler
Diisononyl phthalate
poly(Ethylacrylate-co-vinyl
chloride)
Stainblocker
Other additives
Fiberglass
Virgin PVC
787 (2.58)
161 (0.53)
321 (1.05)
2518(8.25)
636 (2.08)
390(1.28)
12.2 (0.04)
93 (0.30)
52(0.17)
261 (0.86)
Data for Nylon 6,6 and styrene butadiene latex are based on recent European data from the
plastics industry.149'150 Data for polypropylene, PET, and PVC are based on American
Chemistry Council 2006 data developed for submission to the U.S. LCI Database, and data for
limestone comes directly from the U.S. LCI Database. Data for the remaining nylon carpet
materials are derived from elements in the SimaPro database, which include North American and
European data from the late 1990s and 2000s.
Manufacturing
Energy Requirements. Carpet manufacturing consists of a number of steps, including formation
of the synthetic fibers; dyeing of the fibers; and construction, treatment, and finishing of the
carpet. For both nylon carpet types, the nylon material is made into fibers and then 'tufted' to
149 Boustead, I.(Association of Plastics Manufacturers of Europe, March 2005). Found at:
www .plasticseurope.org.
150 Boustead, I.(Association of Plastics Manufacturers of Europe, March 2005) and Boustead, I. (Association of
Plastics Manufacturers of Europe, March 2005). Found at: www.plasticseurope.org.
177
-------
produce the carpet face. The face yarn is attached, using a primary coating and tufting needles,
to the polymer backing. The energy requirements for these process steps are provided in the
following Table.
Broadloom Tile
Electricity 0.39 (34) 2.2 (197)
Fuel Oil 5.0(437) 3.5(306)
Heating Steam 1.67 (145) 2.4 (207)
Emissions. Emissions associated with the manufacturing process arise from the production of
electricity and the combustion of fuel oil and natural gas, and are based on the U.S. LCI
Database.
Solid Wastes. Approximately 9 % and 7 % waste is generated from the production of nylon
broadloom carpet and carpet tile, respectively. Included in these figures are customer returns and
off-specification production. All waste is assumed to be disposed of in a landfill.
Water Consumption. Approximately 0.96 kg/m2 (0.20 lb/ft2) and 0.93 kg/m2 (0.19 lb/ft2) of
water is consumed during the manufacture of nylon broadloom carpet and carpet tile,
respectively.
Transportation. Transport of raw materials to the carpet manufacturing plant is assumed to
cover 402 km (250 mi) by truck.
Transportation
Transportation of nylon carpet by heavy-duty truck to the building site is modeled as a variable
of the BEES system.
Installation
Nylon broadloom carpet and nylon carpet tiles are installed using either a standard latex glue or
a low-VOC latex glue. For the tile, typical glue application is 0.012 kilograms (0.026 Ib) of glue
per ft2 of installed tile. For the broadloom carpet, two applications of glue are required - 0.624
kg/m2 (0.128 lb/ft2) is applied to the product and then spots of glue are applied to the floor space
at a rate of 0.022 kg/m2 (0.004 lb/ft2).
No glue is assumed to be wasted during the installation process, yet 5.7 % of the broadloom
carpet and 2 % of the carpet tile are assumed to be lost as landfilled waste.
Use
The use phase of this product is either 11 years or 15 years depending on the type of nylon
carpeting, broadloom or tile, respectively. As with all BEES products, life cycle environmental
burdens from these replacements are included in the inventory data. Volatile Organic
Compound (VOC) off-gassing from the carpet and both traditional and low-VOC adhesives are
included in the BEES modeling.
178
-------
End of Life
At end of life, a recycle rate of 0.7 % is assumed for broadloom carpet, while none of the carpet
tile is recycled. The nylon carpet and its adhesives are assumed to be disposed of in a landfill.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0LCA Software. 2005. The Netherlands.
Boustead, I, Eco-profiles of the European Plastics Industry: POLY AMIDE 66 (NYLON 66)
(Association of Plastics Manufacturers of Europe, March 2005). Found at:
www.plasticseurope.org.
Boustead, I, Eco-profiles of the European Plastics Industry: STYRENE (Association of
Plastics Manufacturers of Europe, March 2005).
Boustead, I, Eco-profiles of the European Plastics Industry: BUTADIENE (Association of
Plastics Manufacturers of Europe, March 2005). Found at: www.plasticseurope.org.
3.13.7 Generic Wool Carpet
In BEES, wool carpet with a 25-year life is studied. The mass of 0.09 m2 (1 ft2) of wool
broadloom carpet or carpet tile is approximately 40 oz (1.13 kg). Four different product
combinations are included in the BEES database. These combinations are listed below, along
with their corresponding environmental performance data file names. Data files may be viewed
by opening them under the File/Open menu item in the BEES software.
• C3020G.DBF—Wool Carpet Tile with Traditional Glue
• C3020J.DBF—Wool Carpet Tile with Low-VOC Glue
• C3020M.DBF—Wool Broadloom Carpet with Traditional Glue
C3020P.DBF—Wool Broadloom Carpet with Low-VOC Glue
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
179
-------
Wool Carpet Manufacturing
Polypropylene
Production
PVC
Production
Styrene
Butadiene
Production
Calcium
Carbonate
Production
Figure 3.36: Wool Carpet System Boundaries
Raw Materials
Wool carpeting consists of a mix of wool for the facing, a polymer for the backing, and a styrene
butadiene/limestone mix that is used to adhere the facing to the backing. The difference between
the tile and broadloom carpets is the polymer that makes up the backing, as shown below.
Table 3.93: Wool Carpet Constituents
Constituent
Broadloom
Face Fiber
Backing
Tile
Face Fiber
Backing
Material
Wool
Polypropylene
Styrene butadiene latex
CaCO3 filler
Wool
Virgin PVC
Styrene butadiene latex
CaCO3 filler
g/m2 (oz/tf)
1 571 (5.11)
139 (0.45)
254(0.83)
750 (2.44)
1 517(4.94)
133 (0.43)
244 (0.79)
724 (2.36)
Data for wool production comes from the U.S. LCI Database. Production data for the remaining
materials in the carpet comes from the U.S. LCI Database and elements of the SimaPro database,
which is based on North American and European data from the late 1990s and 2000s.
Raw wool is greasy and carries debris that needs to be washed off in a process called "scouring."
The amount of washed wool per kg of raw wool is 80 %, as shown in the table below along with
180
-------
mass fractions for other raw wool constituents reported by the Wool Research Organization of
New Zealand (WRONZ).
Table 3.94: Raw Wool Constituents
Constituent Mass Fraction
Clean fiber (ready to be carded and spun) 80
Grease 6
Suint salts 6
JDirt [[[ 8 .................................................
Grease is recovered at an average rate of 40 %.151 The scoured fiber is then dried, carded, and
spun. The table below lists the main inflows and outflows for the production of wool yarn from
raw wool as reported by WRONZ.152
Table 3.95: Wool Yam
Flow Amount per kg (per Ib)
wool yarn
Input
Natural Gas 5.375 MJ (3.29 kWh)
Electricity 0.70 MJ (0.43 kWh)
Lubricant 0.063 kg (0.31 Ib)
Water 37.5 L (21.79 gal)
Output
Wool yarn153 1 kg (4.85 Ib)
Water emissions due to
scouring: 4.125 g (0.02 Ib)
Biochemical Oxygen 11.625 g (0.06 Ib)
Demand
Most of the required energy is used at the scouring step. Since grease is a co-product of the
scouring process, a mass-based allocation is used to determine how much of the energy entering
this process is due exclusively to the production of washed wool. One-fourth of the required
energy is used for drying. Lubricant is added for blending, carding, and spinning, and some
lubricant is incorporated into the wool. Approximately 6 % of the wool is lost during the
blending, carding, and spinning processes of yarn production; this waste is accounted for in the
BEES data for the manufacturing life-cycle stage.
Manufacturing
Energy Requirements and Emissions.
Wool yarn production into carpet fiber requires additional steps including bleaching, dyeing, and
finishing. The inputs to the bleaching process, provided in the table below, are based on a Best
-------
Available Techniques document for the textile industry.154 No energy data are available for
bleaching, and information for dyeing and finishing is not sufficient to permit inclusion in the
BEES model.
kg/kg (= Ib/lb) Wool
Input
Yarn
Stabilizer 0.030
Sodium Tri-Polyphosphate 0.015
Hydrogen Peroxide (3 5%) 0.200
Formic Acid (85%) 0.002
jSojc^^
For both wool carpet types, the wool must be "tufted" to produce the carpet face. The face yarn
is attached, using a primary coating and tufting needles, to the carpet backing. The energy
requirements for this process step are provided in the following table.
Table
Electricity 1.79(0.05)
Natural Gas
_JTotal_^^
Emissions associated with the manufacturing process arise from the production of electricity and
the combustion of natural gas, and are based on the U.S. LCI Database.
Solid Wastes. Nearly 0.01 kg (0.02 Ib) of waste is generated from the production of 0.09 m2 (1
ft2) of wool broadloom and tile carpeting. The waste is assumed to be disposed of in a landfill.
Transportation. Truck transport of raw materials to the manufacturing plant is assumed to
require 402 km (250 mi) by truck, with the exception of wool, which is transported 1 600 km
(1000 mi).
Transportation
The distance for transport of wool broadloom carpet and wool carpet tile by heavy-duty truck to
the building site is modeled as a variable of the BEES system.
Installation
Wool broadloom carpet and wool carpet tile both are installed using either standard latex glue or
a low-VOC latex glue. For the tile, a typical glue application is 0.13 kg/m2 (0.03 Ib/ft2) of glue
per unit installed tile. For the broadloom carpet, 0.13 kg/m2 (0.14 Ib/ ft2) is applied.
154 European Commission, Integrated Pollution Prevention and Control (IPPC): Best Available Techniques for
the Textile Industry (July 2003), p. 135.
182
-------
No glue is assumed to be wasted during the installation process, but 5.7 % of the broadloom
carpet and 2 % of the wool tile are assumed to be lost as waste; this waste is accounted for in the
BEES data for the manufacturing life-cycle stage. All waste is assumed to be disposed of in a
landfill.
Use
With a life of 25 years, the carpet is installed twice over a 50-year period. As with all BEES
products, the environmental burdens from replacement are included in the inventory data. VOC
off-gassing from the carpet and its installation adhesives are included in the BEES modeling.
End of Life
At end of life, the wool broadloom carpet and carpet tile are assumed to be disposed of in a
landfill.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0LCA Software. 2005. The Netherlands.
European Commission, Integrated Pollution Prevention and Control (IPPC): Best Available
Techniques for the Textile Industry (July 2003).
3.13.8 Forbo Linoleum
Linoleum is a resilient, organic-based floor covering consisting of a backing covered with a thick
wearing surface. Oxidized linseed oil and rosin are mixed with the other natural ingredients to
form linoleum granules. These granules are then calendared onto a jute backing, making a
continuous long sheet. The sheets are hung in drying rooms to allow the naturally occurring
process to continue until the product reaches the required flexibility and resilience. The sheets
are then removed from the drying rooms, cut into rolls, and prepared for shipment.
Forbo Marmoleum may be installed using either a styrene-butadiene or a no-VOC adhesive.
Both installation options are included in BEES. The detailed environmental performance data for
these product options may be viewed by opening the following files under the File/Open menu
item in the BEES software:
• C3020R.DBF—Forbo Marmoleum with Standard Adhesive
• C3020NN.DBF—Forbo Marmoleum with No-VOC Adhesive
Flow Diagram
The flow diagram below shows the major elements of the production of this product as it is
currently modeled for BEES.
183
-------
Forbo Marmoleum Flooring
Truck Functional Unit
Bldg Site
Raw material Adhesive Marmoleum
i L
Process energy
Transport by
ship
Transport by
train
Transport by
truck
T T t ' t t " t
Acrylic Limestone Sawdust Tall oil L nseed oil
Lacquer Production Production Production Production
Production
t + -
Wood Prod'n Flax seed
& Harvesting Production
t
Rosin Jute Pigment
Production Production Production
t
production
1 1
Fertilizer Agrichem cals
production production
Figure 3.37: Forbo Marmoleum System Boundaries
Raw Materials
The Table below lists the constituents of 2.5 mm (0.10 in) linoleum and their proportions.
Table 3.98: Forbo Marmoleum Constituents
Constituent
,, „ ,„ Mass per Applied Area
Mass Fraction155 .f _ , 2 t,, //v2 >
Linseed oil
Tall oil
Pine rosin
Limestone
Wood flour
Pigment
Jute (backing)
Acrylic lacquer
Total:
20%
13%
3%
20%
31%
4%
8%
1%
100 %
588(0.12)
398 (0.08)
76 (0.02)
592(0.12)
901 (0.18)
101 (0.02)
233 (0.05)
12 (0.00)
J^oiJMEI
For lack of other available data, the cultivation of linseed is based on a modified version of
wheat production from the U.S. LCI Database. To harvest the linseed, it is assumed that a diesel
tractor is used - approximately 0.61 MJ (0.17 kWh) of diesel is consumed per kg (263 Btu/lb) of
' Marieke Goree, Jeroen Guinea, Gjalt Huppes, Lauran van Oers(The Netherlands: Leiden University, 2000).
184
-------
linseed harvested. The yield for linseed is 1 038 kg per hectare (420 Ib per acre). Energy
requirements for linseed oil production include fuel oil and steam, and are allocated on an
economic basis between linseed oil (87%) and linseed cake (13 %). Allocation is necessary
because linseed cake is a co-product of linseed oil production, so its production impacts should
not be included in the BEES model. The emissions associated with linseed oil production are
allocated on the same economic basis. The production of the fertilizers and pesticides is based
on elements of the SimaPro database.
The production of tall oil is based on European data for kraft pulping, with inventory flows
allocated between kraft pulp and its coproduct, tall oil.156 Pine rosin production is assumed to
have no burdens, since the harvesting of raw pine rosin is done mainly by hand, according to
Forbo.
The production of limestone comes from the U.S. LCI Database. Wood flour is sawdust
produced as a coproduct of wood processing, and its production is based on the U.S. LCI
Database.
Data for production of the pigments used in the product is modeled based on the European
production of titanium dioxide, and comes from the SimaPro database. Linoleum backing, jute,
is mostly grown in India, Bangladesh, Thailand, and China. Jute is a predominantly rain-fed and
requires little fertilizer and pesticides, and cultivation is generally manual. Data for the
production of acrylic lacquer materials is based on elements of the SimaPro database.
2
Manufacturing
Energy Requirements and Emissions. The production of each unit of Marmoleum (0.09 mz or
1 ft2) requires 0.45 MJ (0.13 kWh) of electricity and 1.8 MJ (0.5 kWh) of natural gas. Burdens
from the production and use of energy are based on the U.S. LCI Database.
Transportation. Transportation distances for shipment of the raw materials from the suppliers to
the manufacturing plant in Europe are provided by Forbo. In addition to raw materials transport,
the manufacturing life-cycle stage includes transport of the finished product from the European
manufacturing plant to the United States. All of these requirements, involving transport by diesel
truck, rail, and ocean freighter, are accounted for, with data based on the U.S. LCI Database.
Transportation
Transportation by diesel truck of the finished product from the U.S. distribution facility to the
building site is modeled as a variable in BEES.
Installation
Marmoleum may be installed using 0.0003 kg (0.0007 Ib) of either a styrene-butadiene or a no-
VOC adhesive. Additionally, an acrylic sealant is applied to the flooring at each installation.
Approximately 6 % of the flooring is wasted and landfilled at installation.
Use
156 Federation Europeenne des Fabricates de Carton Ondule (FEFCO), 2003. Found at:
http://www.fefco.org/fileadmin/Fefco/pdfs/Technical_PDF/Corrected_database_2003.pdf.
185
-------
Linoleum is known for its durability. Through evaluation of actual lifetime data, it has been
determined that linoleum has a useful life of 30 years.157 As with all BEES products, the life
cycle environmental burdens from replacement are included in the inventory data.
End of Life
At the end of its life, the used flooring is sent to a landfill.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Marieke Goree, Jeroen Guinee, Gjalt Huppes, Lauran van Oers, Environmental Life Cycle
Assessment of Linoleum (The Netherlands: Leiden University, 2000).
Federation Europeenne des Fabricants de Carton Ondule (FEFCO), European Database for
Corrugated Board Life Cycle Studies, 2003. Found at:
http://www.fefco.Org/fileadmin/F efco/pdfs/Technical_PDF/Corrected_database_2003.pdf
Federal Association of the Sworn Experts for Room and Equipment e.V., Guide to the Inquiry
of Time Values and Decreases in Value of Floor Coverings, (Bonn, Germany: Federal
Association of the Sworn Experts for Room and Equipment e.V.).
Industry Contacts
Tim Cole, Forbo Industries (2002)
3.13.9 UTT Soy Backed Nylon Carpet
Based in Dalton, GA, Universal Textile Technologies (UTT) supplies the carpet and synthetic
turf industries with multiple backing systems, including polyurethane backings. BEES includes
a nylon carpet made with Biocel, a polyurethane backing for carpets and artificial turf in which a
soybean-based polyol replaces a portion of the inputs required to make traditional polyurethane
backing.
The detailed environmental performance data for this nylon carpet with a soy polyol backing
may be viewed by opening the file C3020U.DBF, for installation with a standard adhesive, and
C3020PP.DBF, for installation with a low-VOC adhesive, under the File/Open menu item in the
BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product as it is
currently modeled for BEES.
157 Federal Association of the Sworn Experts for Room and Equipment e.V., Guide to the Inquiry of Time Values
and Decreases in Value of Floor Coverings(Bonn, Germany: Federal Association of the Sworn Experts for Room
and Equipment e.V.).
186
-------
UTT Soy Urethane -Backed Broadloom Carpet
jmc Functional Unit
T rf( » of UTT ,.
Bid Sit Br°adl°°
Carpe
i L
Latex Adhesive
Raw material fc _ . .
transport
En o Lif
Carpe
production
i
Prnces
energy
*
Raw material
transport
T t T t
Petroleu So Polyo
Polyo Production
Production
T
Soybean &
Soy
Production
Isocyanate
Production
Fille Yar
Productio Spinnin
n
t
Nylon 6,6
Production
Figure 3.38: UTT Broadloom Carpet System Boundaries
Raw Materials
The following Table presents the product constituents and their relative shares of the product
mass.
Table 3.99: UTT Broadloom Carpet Constituents
Constituent Mass Fraction
Soy Polyol
Petroleum Polyol
Nylon Yarn
Isocyanate
Fillers
Other Additives
11 %
11%
31%
9%
31%
7%
The yarn consists of Nylon 6,6, represented in BEES by European data from the plastics
industry.158 Data for the production of poly ether polyol and isocyanate is provided by American
Chemistry Council 2006 data developed for submission to the U.S. LCI Database and elements
of the SimaPro database. Soy polyol production is based on life cycle soybean oil production
data developed for the U.S. Department of Agriculture (USDA),159 updated to reflect a newer
manufacturing process for the oil processing.
158 Boustead, I.(Association of Plastics Manufacturers of Europe, March 2005). Found at:
www .plasticseurope.org.
159 Sheehan, J. et al, NREL/SR-580-24089 (Washington, DC: US Department of Agriculture and US
Department of Energy, May 1998).
187
-------
Fillers include limestone and fly ash. Limestone data comes from the U.S. LCI Database. Fly
ash, the mineral residue produced by burning coal, is captured from electricity-generating power
plants' exhaust gases and collected for disposal or use. When used, this byproduct is assumed to
be an environmentally "free" input material, although its transport to the production site is
included in the BEES model. Data for all other additives are taken from elements of the
SimaPro database.
Manufacturing
Energy Requirements and Emissions. The manufacturing process for UTT soy backed nylon
carpet consists of forming the polyurethane backing, curing the backing, and adhering it to the
nylon facing. Site data are used to quantify the energy inputs to the production process, which
consist of purchased electricity (0.021 kWh/ft2) and natural gas (0.23 MJ/ft2). Data for all
energy precombustion and use comes from the U.S. LCI Database.
Transportation. Transportation distances for shipment of the raw materials from the suppliers to
the manufacturing plant are provided by UTT. The materials are transported by diesel truck,
based on the U.S. LCI Database.
Transportation
Transport by diesel truck from the manufacturing plant in Dalton, Georgia to the building site is
based on data from the U.S. LCI Database. The BEES user is free to adjust the default
transportation distance.
Installation
The installation adhesive for the standard UTT carpet product is assumed to be the same
traditional contact adhesive used to install the generic BEES carpet products. The other UTT
carpet product is installed using a low-VOC adhesive . For both, the average application is
assumed to require 0.65 kg adhesive/m2 (0.13 lb/ft2). About 3.5% of the product is wasted
during its installation.
Use
The lifetime of UTT broadloom carpet is assumed to be 11 years, consistent with the 11-year
lives assumed for the other broadloom carpets in BEES, so it is replaced 4 times after the initial
installation over the 50-year BEES use period. As with all BEES products, the life cycle
environmental burdens from these replacements are included in the inventory data.
End of Life
At each replacement, it is assumed that 5 % of the used carpet is recycled, with the remaining
95 % going to a landfill.
188
-------
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Boustead, I, Eco-profiles of the European Plastics Industry: POLYAMIDE 66 (NYLON 66)
(Association of Plastics Manufacturers of Europe, March 2005). Found at:
www.plasticseurope.org.
Sheehan, J. et al., Life Cycle Inventory ofBiodiesel and Petroleum Diesel for Use in an Urban
Bus, NREL/SR-5 80-24089 (Washington, DC: U.S. Department of Agriculture and U.S.
Department of Energy, May 1998).
Industry Contacts
Jim Pollack, Omnitech International (2005)
3.13.10 C&A Carpet
C& A is a manufacturer of modular tile and six-foot structured back carpeting for the commercial
market. As part of Tandus, C&A works with sister brands Monterey and Crossley to provide
customized floor covering solutions for its customers. The four C&A products listed below are
included in BEES.
Table 3.100: C&A Products Included in BEES
Product_Line ^ty^e
ER3 RS Modular Tile Habitat (nylon 6,6 with 80 % pre-consumer
content)
ER3 RS Cushion Roll Goods Intersection (nylon 6,6 with 90 % pre-
consumer content)
Ethos RS Modular Tile Topography (nylon 6,6 with 80 % pre-
consumer content)
Ethos RS Cushion Roll Goods Yosemite (nylon 6,6 with 80 % pre-
consumer content)
Some of C&A's carpets are available as "climate neutral" products, meaning the greenhouse
gases emitted over their life cycles are optionally offset or balanced. The BEES user may choose
either the traditional or climate neutral versions of these products when selecting them for
analysis.
The detailed environmental performance data for these products may be viewed by opening the
following files under the File/Open menu item in the BEES software:
• ER3 RS Modular Tile: C3020X.DBF
• ER3 RS Cushion Roll Goods: C3020Y.DBF
• Ethos RS Modular Tile: C3020Z.DBF
189
-------
• Ethos RS Cushion Roll Goods: C3020AA.DBF
Flow Diagram
The flow diagrams below show the major elements of the production of these products as they
are currently modeled for BEES.
C&A ER3 Cushion Roll Goods and Carpet Tile
Truck
Transport to
BldgSite
kb Pre-applied
Raw material k Arlhn'-i-n
transport prnriuntinn
t
Acrylic
Production
Functional U
* of ER3 Carp
Products
t
Primary
Backing raw
materials
nit
Carpet
prnr|i|nti<~in
t T
Rec'd Vinyl Limesto
grinding & Product
processing
t
Recycled
Vinyl
-, Process
energy
^
Raw material
. .
T
ne Yarn
on Spinning
t
I
Virgin Recycled
Nylon 66 N ,on 66
Production
Figure 3.39: C&A ER3 Flooring Products System Boundaries
190
-------
C&A Ethos Cushion Roll Goods and Carpet Tile
Primary
Backing raw
materials
Rec'd PVB
grinding &
processing
Limestone
Production
Recycled
PVB
Recycled
Nylon 66
figure 6.41): L.&A Ethos flooring t^oducts System Boundaries
Raw Materials
The following tables present the constituents by mass percentage of the ER3 and Ethos products.
Constituent
ER3 Tile ER3 Cushion Roll
Mass Fraction Mass Fraction
Nylon 6,6 Yarn
Post-industrial nylon 6,6
Primary backing
Recycled vinyl/Limestone (filler)
Other Additives (precoat, etc.)
Total:
2%
10%
5%
72%
11%
100 %
2%
17%
4%
62%
15%
100 %
Constituent
Nylon 6,6 Yarn
Post-industrial nylon 6,6
Primary backing
Recycled PVB/ Limestone (filler)
Other Additives (precoat, etc.)
Total:
Ethos Tile
MassJFmction
3%
11%
4%
65%
Ethos Cushion Roll
MassJFmction
3%
11%
4%
65%
191
-------
Yarn for the ER3 products consists primarily of post-industrial (PI) nylon 6,6. While producing
the PI nylon 6,6 is not—and should not—be accounted for, spinning it into yarn plus its
transportation to the manufacturing site is taken into account in the model. Data for the
production of virgin nylon 6,6 comes from the European plastics industry.160
The secondary backing for ER3 products is made from recycled post consumer (PC) and PI vinyl
backed carpet and waste. As with the PI nylon 6,6, no production data is included, with the
exception of data for the material's processing into backing and transportation to the site.
The secondary backing for Ethos products is made from PC polyvinyl butyral (PVB) film
recovered from windshield and safety glass recycling facilities. The transportation and
processing of the PVB are accounted for in the model.
Data for materials in the primary backing and for other additives comes from the U.S. LCI
Database and elements of the SimaPro database, which includes both North American and
European data from the late 1990s and 2000s. Data for the limestone comes from the U.S. LCI
Database.
Manufacturing
Energy Requirements. The manufacturing process for C&A's products consists of tufting the
nylon yarn, applying the precoat compound, and joining the secondary backing. The energy to
produce ER3 tile and the two Ethos products is comprised of 30 % electricity and 70 % natural
gas. The ER3 cushion rolls require more energy to produce due to yarn dyeing processes;
energy sources include electricity (27 %), natural gas (59 %), fuel oil (12 %), and biodiesel
(2 %). The production and use of these energy sources come from the U.S. LCI Database, and
biodiesel production data comes from a National Renewable Energy Laboratory (NREL) LCA
study on biodiesel use in an urban bus.161
Transportation. Transportation distances for shipment of the raw materials from the suppliers to
the manufacturing plant are provided by C&A. Most of the materials are transported exclusively
by diesel truck, while some are transported by both diesel truck and rail. All forms of
transportation are included in the model, and all data is based on the U.S. LCI Database.
Waste. Any waste generated during the manufacturing process is recycled back into other carpet
products.
Transportation
The distance for transport by diesel truck from the C&A manufacturing plant in Dalton, Georgia
to the building site is modeled as a variable in BEES. Transportation emissions allocated to each
product depends on its overall mass, as given in the following Table.
Table 3.103: C&A Products'Mass and Density
160 Boustead, I.(Association of Plastics Manufacturers of Europe, March 2005). Found at:
www .plasticseurope.org.
161 Sheehan, J. et al, NREL/SR-580-24089 (Washington, DC: US Department of Agriculture and US
Department of Energy, May 1998).
192
-------
Mass per Applied Density in
Product
ER3 Modular Tile 4.4 (0.90) 674.4 (42. 1)
ER3 Cushion Roll Goods 3.7 (0.76) 586.3 (36.6)
Ethos Modular Tile 3.9 (0.80) 619.9 (38.7)
thosusliionollGoods
Installation
C&A products are produced with RS pre-applied adhesive, which provides a "peel and stick"
installation system. It simplifies installation, reduces VOC and odors associated with the use of
wet adhesives, and does not require an air-out period. According to C&A, carpet waste of less
than 3 % is generated during installation. Scraps are typically kept at the building site for future
repairs.
Use
C&A's roll products are replaced after 25 years. The modular tile products are replaced after 15
years. As with all BEES products, life cycle environmental burdens from these replacements are
included in the inventory data.
End of Life
All C&A products are 100 % recyclable in their in-house closed-loop recycling process.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel . gov/lci/database.
PRe Consultants: SimaPro 6.0 LC A Software. 2005. The Netherlands.
Boustead, I, Eco-profiles of the European Plastics Industry: POLYAMIDE 66 (NYLON 66)
(Association of Plastics Manufacturers of Europe, March 2005). Found at:
www.plasticseurope.org.
Sheehan, J. et al., Life Cycle Inventory ofBiodiesel and Petroleum Diesel for Use in an Urban
Bus, NREL/SR-5 80-24089 (Washington, DC: U.S. Department of Agriculture and U.S.
Department of Energy, May 1998).
Industry Contacts
Lynn Preston, Tandus (June 2006)
3.13.11 Interface Carpet
Based in Atlanta, Georgia, Interface is active in the global commercial interiors market, offering
modular and broadloom carpets, fabrics, interior architectural products, and specialty chemicals.
Nine Interface carpet products are included in BEES. They are listed below, together with the
names of the BEES files containing their detailed environmental performance data.
193
-------
Bentley Prince Street Division:
• UPC Recycled Nylon Carpet Tile (C3020VV.DBF)
• UPC Recycled Nylon Carpet Tile With Cool Carpet (C3020WW.DBF)
• Scan Recycled Nylon Broadloom Carpet (C3020TT.DBF)
• Scan Recycled Nylon Broadloom Carpet With Cool Carpet (C3020UU.DBF)
• Capri Recycled Nylon Broadloom Carpet (C3020RR.DBF)
• Capri Recycled Nylon Broadloom Carpet With Cool Carpet (C3020SS.DBF)
InterfaceFLOR (TFC) Division:
• Entropy Recycled Nylon And Vinyl Carpet Tile With Cool Carpet (C3020XX.DBF)
• Sabi Recycled Nylon And Vinyl Carpet Tile With Cool Carpet (C3020QQ.DBF)
• Transformation Recycled Nylon And Vinyl Carpet Tile With Cool Carpet (C3020CC.DBF)
Some of Interface's products are "climate neutral" under its Cool Carpet program. Climate
neutral refers to products whose greenhouse gas (GHG) emissions over their life cycles are offset
or balanced. The GHGs of IFC carpets under the Cool Carpet program are offset by 16.1 kg
(35.4 Ib) CO2-equivalents/yd2, while Bentley Prince Street products' GHGs are offset by 22.0 kg
(48.4 Ib) CO2-equivalents/yd2. These values are based upon internal Interface LCAs. Because
these values are greater than those in the life cycle inventories compiled for BEES, the BEES
Global Warming Potential results for Cool Carpets are set to zero. Entropy, Sabi, and
Transformation carpet tiles are always Cool Carpets, while for the other Interface products
offered in BEES, the customer has the choice of purchasing the Cool Carpet option for an
additional cost per square unit. All these options are offered in BEES.
Flow Diagram
The flow diagram below shows the major elements of the production of these products as they
are currently modeled for BEES.
Bentley Prince Street Broadloom Carpet Products
Latex
Truck
Transport to
BldgSite
Adhesive
t
T
c Thickener
x Production
tion
— »
Functional Unit
ot Broadloom * Did-of
Carpet
j
t t
SBR Latex PP
Production Production
Life
Carpet energy
Raw mater a
J. _L
T T
Polyester Limestone Virgin Recy
Production Production Nylon 66 Ny!o
Production
Figure 3.41: Bentley Prince Street Broadloom Carpets System Boundaries
194
-------
InterfaceFLOR Carpet Tile Products
Functional Unit
of Carpet Tile
End-of-Life
PET
Production
Acrylate
Polymer
Production
Recycled Recycled
Nylon 66 Vinyl
Figure 3.42: InterfaceFLOR Carpet Tiles System Boundaries
Raw Materials
Interface's two carpet divisions produce like mixes of materials, as shown in the tables below.
Table 3.104: Bentley ——
Constituent UPC Mass Scan Mass Capri Mass
Virgin Nylon 6^6
Recycled Nylon 6,6
(pre-consumer)
Polypropylene or Polyester
primary backing
SBR Latex backing
Limestone
Other Additives
34
6
11
31
13
34
6
11
31
13
30
10
11
31
13
195
-------
Constituent Entropy Mass Sabi Mass Transformation
Virgin Nylon 6,6 956
Recycled Nylon 6,6 (pre- 55 6
consumer)
Polyester primary backing 22 2
Recycled vinyl backing 22 23 23
(pre-consumer)
Recycled vinyl backing 39 41 40
(post-consumer)
Limestone (filler) 14 15 14
Other Additives 999
Data for nylon resin, polyamide 6,6, comes from publicly-available data from the European
plastics industry.162 Interface provided the energy required to spin the nylon into yarn
(approximately 1.7 MJ/kg yarn). The nylon 6,6 and vinyl used in these carpet products have
significant recycled content. These recycled materials carry no environmental burdens from the
production of the virgin materials. However, they do carry impacts from transport after leaving
the waste stream and subsequent processing. For example, the electricity used to grind down
post-industrial and post-consumer material to a usable size is assigned to the recycled materials.
This data is provided by Interface.
For the broadloom applications, the nylon yarn is back-coated with styrene butadiene rubber
(SBR) to provide stability. Both styrene and butadiene production data come from the most
recent APME data sets.163'164 For the carpet tiles, ethylene vinyl acetate (EVA) is used to bind
the nylon to the primary substrate. Data representing this process comes from public and site-
specific data in the SimaPro database. Data for polypropylene, polyester (polyethylene
terephthalate, or PET), and the limestone filler comes from the U.S. LCI Database.
Manufacturing
Energy Requirements and Emissions. The manufacturing process for the UPC, Scan, and Capri
carpets essentially consists of weaving the nylon yarn, applying the precoat compound, and
joining the yarn to the backing. This process requires both purchased electricity and natural gas.
The production of a ft2 of UPC, Scan, or Capri carpet requires approximately 0.24 MJ (0.07
kWh) of electricity and 2.1 MJ (0.58 kWh) from natural gas.
The manufacturing process for Entropy, Sabi, and Transformation carpet tile products consists of
tufting the nylon yarn, applying the EVA adhesive, and joining the yarn to the backing.
Producing 0.09 m2 (1 ft2) of each of these carpet tiles requires approximately 0.59 MJ (0.16
162 Boustead, I.(Association of Plastics Manufacturers of Europe, March 2005). Found at:
www .plasticseurope.org.
163 Boustead, I.(Association of Plastics Manufacturers of Europe, March 2005). Found at:
www .plasticseurope.org.
164 Boustead, I.(Association of Plastics Manufacturers of Europe, March 2005). Found at:
www .plasticseurope.org.
196
-------
kWh) of electricity and 0.40 MJ (0.11 kWh) from natural gas. All energy production and
consumption data come from the U.S. LCI Database.
Waste. A small amount of manufacturing waste, as reported by Interface, is included in each of
its BEES carpet products.
Transportation. Manufacturer-reported transportation distances for shipment of the raw
materials from the suppliers to the Interface plants are accounted for through diesel truck
modeling based on the U.S. LCI Database.
Transportation
The transportation distance for diesel trucking from the Interface manufacturing plant in Georgia
or California to the building site is modeled as a variable in BEES. The quantity of transportation
emissions allocated to each product depends on the overall mass of the product, as given in the
Table below.
Mass Density
__proibict MyLSMEl MyLSMu^^
Scan
UPC
Capri
Entropy
Sabi
Transformation
2.6(0.53)
2.6(0.53)
2.4 (0.49)
4.4 (0.90)
4.2 (0.86)
4.3 (0.88)
343(21.4)
343(21.4)
318(19.9)
616(38.5)
608 (38.0)
602 (37.6)
Installation
The Interface carpet products evaluated by BEES are installed using a contact adhesive. The
low-VOC TacTiles material, consisting of PET and acrylate polymer, is a tape that is applied
between IFC carpet tiles at installation. A low-VOC glue is used for Bentley Prince Street
installations. The following installation waste percentages are incorporated into the BEES
models: UPC and Scan, 3 %; Capri, 5 %; and Entropy, Sabi, and Transformation, 1 %.
Use
With lifetimes of 15 years, the Entropy, Sabi, UPC, and Transformation carpet tiles are replaced
3 times over the 50-year BEES use period. The broadloom carpets, Scan and Capri, have 11-
year lives, requiring 4 replacements over the use period. As with all BEES products, life cycle
environmental burdens from these replacements are included in the inventory data.
End of Life
According to the manufacturer, at end of life, the Entropy, Sabi, and Transformation carpet tiles
are recycled in a closed loop process, avoiding disposal in a landfill. At end of life for Capri,
UPC, and Scan products, an average of 12.5 % is reclaimed.
197
-------
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 7.0LCA Software. 2005. The Netherlands.
Boustead, I, Eco-profiles of the European Plastics Industry: POLYAMIDE 66 (NYLON 66)
(Association of Plastics Manufacturers of Europe, March 2005). Found at:
www.plasticseurope.org.
Boustead, I, Eco-profiles of the European Plastics Industry: STYRENE (Association of
Plastics Manufacturers of Europe, March 2005). Found at: www.plasticseurope.org.
Boustead, I, Eco-profiles of the European Plastics Industry: BUTADIENE (Association of
Plastics Manufacturers of Europe, March 2005). Found at: www.plasticseurope.org.
Industry Contacts
John Jewell and Paul Firth, Interface (July 2006)
3.13.12 J&J Industries Carpet
J&J Industries is a privately-held manufacturer of commercial carpet, primarily for corporate
interiors but also for healthcare, retail, education, and government facilities. The company
provided data on one of its 0.8 kg (28 oz) products: Certificate with Styrene Butadiene Resin
(SBR) Backing. The detailed environmental performance data for this product may be viewed
by opening the file C3020DD.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product as it is
currently modeled for BEES.
198
-------
J&J Certificate Broadloom Carpet
Figure 3.43: J&J Certificate Broadloom Carpet System Boundaries
Raw Materials
The following Table presents the constituents of the J&J product and their relative quantities.
Table 3.107: J&J Certificate Broadloom Carpet Constituents
Constituent Mass Fraction
Yarn (Nylon 6)
Styrene Butadiene Resin
(SBR)
Limestone
Other Additives
32%
10%
41 %
16%
The yarn consists of Nylon 6, which is produced from the polymerization of caprolactam and
whose BEES data comes from public data provided by the European plastics industry.165 The
SBR used in the carpet comes from European plastics data on styrene166 and butadiene.167
Limestone filler production data comes from the U.S. LCI Database.
Boustead, I.(Association of Plastics Manufacturers of Europe, March 2005). Found at:
www .plasticseurope.org.
166 Boustead, I.(Association of Plastics Manufacturers of Europe, March 2005). Found at:
www .plasticseurope.org.
167 Boustead, I.(Association of Plastics Manufacturers of Europe, March 2005). Found at:
www .plasticseurope.org.
199
-------
Manufacturing
Energy Requirements and Emissions. Certificate's manufacturing process consists of tufting
the nylon yarn and joining the yarn to the backing. This process uses purchased electricity,
natural gas, and other fossil fuels. The production of one unit of carpet (0.09 m2, or 1 ft2)
requires 1.2 MJ (0.34 kWh) of electricity, 1.58 MJ (0.439 kWh) of natural gas, and less than 0.03
MJ (0.01 kWh) of other fossil fuels. Energy production and combustion data are modeled based
on the U.S. LCI Database.
Transportation. Transportation distances for shipment of the raw materials from the suppliers to
the manufacturing plant are provided by J&J. The materials are transported by diesel truck,
based on the U.S. LCI Database.
Transportation
The distance for diesel truck transport from the J&J manufacturing plant in Dalton, Georgia to
the building site is modeled as a variable in BEES, and transportation burdens are based on data
from the U.S. LCI Database.
Installation
Certificate broadloom carpet is assumed to be installed using a low-VOC adhesive. The average
application is assumed to require 0.03 kg (0.07 Ib) of adhesive per unit of carpet (0.09 m2, or 1
ft2). On average, 7 % of the carpet and 5 % of the adhesive are lost during installation.
Use
The lifetime of the carpet is assumed to be 11 years, consistent with lives for other broadloom
carpets in BEES, and meaning it is replaced 4 times after initial installation over the 50-year
BEES use period. As with all BEES products, life cycle environmental burdens from these
replacements are included in the inventory data.
End of Life
At end of life, it is assumed that Certificate is sent to the landfill.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Boustead, I, Eco-profiles of the European Plastics Industry: POLYAMIDE 6 (NYLON 6)
(Association of Plastics Manufacturers of Europe, March 2005). Found at:
www.plasticseurope.org.
Boustead, I, Eco-profiles of the European Plastics Industry: POLYAMIDE 66 (NYLON 66)
(Association of Plastics Manufacturers of Europe, March 2005). Found at:
www.plasticseurope.org.
Boustead, I, Eco-profiles of the European Plastics Industry: BUTADIENE (Association of
Plastics Manufacturers of Europe, March 2005). Found at: www.plasticseurope.org.
200
-------
Industry Contacts
Howard Elder, J&J Industries (2002)
3.13.13 Mohawk Carpet
Mohawk Industries is the second-largest manufacturer of commercial and residential carpets and
rugs in the United States and one of the largest carpet manufacturers in the world. Mohawk is
involved in all aspects of carpet and rug production, from raw materials development to
advanced tufting, weaving, and finishing. The company provided data on two broadloom carpets:
Regents Row, a woven commercial carpet, and Meritage, a tufted commercial carpet. The
detailed environmental performance data for these products may be viewed by opening the
following files under the File/Open menu item in the BEES software:
• C3 020FF .DBF—Mohawk Regents Row
• C3020GG.DBF—Mohawk Meritage
Flow Diagram
The flow diagrams below show the major elements of the production of these products as they
are currently modeled for BEES.
201
-------
Mohawk Regents Row Broadloom Carpet
Truck
Bldg Site
Green Seal
Production
A i
Nylon
Yar
Produc
Functional Unit
of Regents Row
Carpet
End-of-Life
Car
produ
i
T
66 Polyprop.
n Yarn
tion Production
pet
ction
Process
energy
^ 1
I Raw material
transport
t
Polyester
Yarn
Production
Styrene Fillers &
Butadiene additives
latex prod'n production
Figure 3.44: Mohawk Regents Row Broadloom Carpet System Boundaries
Mohawk Meritage Broadloom Carpet
Green Seal
Certified Adhesive
Production
Recycled
Nylon 6
Figure 3.45: Mohawk Meritage Broadloom Carpet System Boundaries
202
-------
Raw Materials
The two Mohawk carpets are produced from different materials and have different ratios of
backing to yarn. The mixture of the main constituents of each carpet is listed in the Table below.
„ ,., , Resents Row Meritage
Constituent ** r *• ** r ^
Mass Fraction Mass Fraction
Yarn (nylon 6; 50 % recycled)
Yarn (nylon 6,6)
Backing
Precoat and other additives
—
51%
16%
33%
49%
—
9%
42%
The yarn for Regents Row carpet consists of woven nylon 6,6. Data for the production of virgin
nylon 6,6 is publicly-available from the European plastics industry.168 The yarn for Meritage
carpet is 50/50 recycled-virgin nylon 6. The virgin nylon 6 is produced from the polymerization
of caprolactam and is based on publicly-available European data.169 While producing the
recycled nylon 6 is not—and should not be—accounted for, spinning it into yarn plus its
transportation to the manufacturing site are included in the BEES model.
The backing for the Regents Row carpet is a 50/50 mix of polypropylene and polyester fibers.
The Meritage carpet only uses polypropylene for the backing material. Data for these backing
materials comes from American Chemistry Council 2006 data developed for submission to the
U.S. LCI Database.
Since the Regents Row carpet is woven, the nylon yarn is back-coated with styrene butadiene
latex to provide stability. For the Meritage carpet, Ethylene Vinyl Acetate (EVA) is used to
adhere the backing to the tufted nylon. Life cycle inventory data for styrene and butadiene are
taken from European plastics data,170 and EVA data are derived from elements of the SimaPro
database. A majority of the "other additives" is limestone filler, whose data is based on the U.S.
LCI Database. The remaining additives' production data are based on the SimaPro database and
U.S. LCI Database.
Manufacturing
Energy Requirements and Emissions. The manufacturing process for Mohawk Regents Row
carpet consists of interlacing face yarns with backing yarns which are then coated with finish
chemicals. This process requires both purchased electricity and natural gas. The production of
each unit of Regents Row carpet (0.09 m2, or 1 ft2) requires 0.4 MJ (0.1 kWh) of electricity and
0.73 MJ (0.20 kWh) of natural gas. The manufacturing process for Meritage consists of tufting
the nylon yarn into the backing foundation and coating the fabric with the EVA chemical system.
This process requires 0.6 MJ (0.18 kWh) of electricity and 0.71 MJ (0.20 kWh) of natural gas
168 Boustead, I.(Association of Plastics Manufacturers of Europe, March 2005). Found at:
www .plasticseurope.org.
169 Boustead, I.(Association of Plastics Manufacturers of Europe, March 2005). Found at:
www .plasticseurope.org.
170 Boustead, I.(Association of Plastics Manufacturers of Europe, March 2005) and Boustead, I. (Association of
Plastics Manufacturers of Europe, March 2005). Found at: www.plasticseurope.org.
203
-------
per unit. All energy production and combustion data is based on the U.S. LCI Database.
Transportation. Transportation distances for shipment of the raw materials by diesel truck from
the suppliers to the manufacturing plant are provided by Mohawk. Diesel trucking burdens are
based on the U.S. LCI Database.
Transportation
The transportation distance from the Mohawk manufacturing plant in South Carolina or Georgia
to the building site is modeled as a variable in BEES. Both products are shipped by diesel truck.
The quantity of transportation emissions allocated to each product depends on the overall mass
of the product, as given in the Table below.
Mass per Applied Area in Density in
Regents Row 2.34 (0.47) 336.67 (22.27)
JMeritage 2^1 {0.48) 346. 67 {22.93)
Installation
Both Mohawk carpets are installed using a low-VOC adhesive. The average application requires
about 0.04 kg (0.09 Ib) of adhesive per unit of carpet (0.09 m2, or 1 ft2). For both carpets,
approximately 5 % of the carpet and adhesive is wasted during installation; this is incorporated
into the BEES product models.
Use
All BEES nylon broadloom carpets are assumed to have lifetimes of 11 years. Thus, both
Mohawk broadloom carpets are assumed to be replaced four times over the 50-year BEES use
period. As with all BEES products, life cycle environmental burdens from these replacements are
included in the inventory data.
End of Life
At end of life, it is assumed that the Mohawk products are sent to the landfill.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel . gov/lci/database.
PRe Consultants: SimaPro 6.0 LC A Software. 2005. The Netherlands.
Boustead, I, Eco-profiles of the European Plastics Industry: POLYAMIDE 66 (NYLON 66)
(Association of Plastics Manufacturers of Europe, March 2005). Found at:
www.plasticseurope.org.
Boustead, I, Eco-profiles of the European Plastics Industry: POLYAMIDE 6 (NYLON 6)
(Association of Plastics Manufacturers of Europe, March 2005). Found at:
www.plasticseurope.org.
Boustead, I, Eco-profiles of the European Plastics Industry: STYRENE (Association of
204
-------
Plastics Manufacturers of Europe, March 2005) and Boustead, I, Eco-profiles of the
European Plastics Industry: BUTADIENE (Association of Plastics Manufacturers of Europe,
March 2005). Found at: www.plasticseurope.org.
Industry Contacts
Frank Endrenyi, Mohawk Industries (2002)
3.13.14 Natural Cork Flooring
Natural Cork is a U.S. supplier of cork flooring and wall coverings. It distributes products
manufactured by Granorte, a Portuguese company that recycles cork waste from the production
of cork bottle stoppers. The energy used to produce the cork tiles comes mainly from waste cork
powder. Natural Cork provided data on two of its products: cork parquet tile and cork floating
floor plank. The detailed environmental performance data for these products may be viewed by
opening the following files under the File/Open menu item in the BEES software:
• Natural Cork Parquet Floor Tile —C3020HH.DBF
• Natural Cork Floating Floor Plank—C3020II.DBF
Flow Diagram
The flow diagrams below show the major elements of the production of these products as they
are currently modeled for BEES.
205
-------
Natural Cork Parquet Tile
Process energy
Raw material
transport by ship
Raw material
transport by truck
Recycled Cork
Waste
Figure 3.46: Natural Cork Parquet Floor Tile System Boundaries
Natural Cork Floating Floor Plank
jruck Functional Unit
-!-.-„.„-.,„,* »„ k of Floating Floor „ c_ . „
BldgSite Plank
i i
Raw material Adhesive Cork
productio
i i
T
Recycled Polyurethf
Cork Binder
Processing Productic
T
Recycled Cork
Waste
-Life
Process enerq
^ Raw material
n transport by sh
Raw material
transport by true
T
me High Density
Fiberboard
)n Production
t
Wood Wood
Harvesting Waste
/
P
;k
Figure 3.47: Natural Cork Floating Floor Plank System Boundaries
206
-------
Raw Materials
Both Natural Cork floor products use a cork sheet made from a combination of recycled cork
waste and urethane binder. The floating floor plank also includes a layer of High Density
Fiberboard (HDF) cut into a tongue-and-groove pattern. The mixture of the main constituents of
each floor product is listed in the Table below.
„ . Parquet Floor Floating Floor
Constituent * ° .
Mass Fraction Mass Fraction
Recycled Cork Waste
Binder
High Density Fiberboard
93%
7%
—
58%
3%
39%
Since the cork constituent is a waste product, the environmental burdens from virgin production
of the cork are not included. The energy used to grind the cork, however, is included, as is its
transportation to the manufacturing facility. HDF is produced mostly from recovered wood waste
- only 14 % of the wood going into HDF is harvested directly. In the absence of available data,
HDF manufacturing is represented, by proxy, with oriented strand board (OSB) production data
provided by the U.S. LCI Database and described in more detail under Generic Oriented Strand
Board Sheathing.
The binder for Natural Cork flooring is a moisture-cured urethane, produced from a reaction
between polyisocyanate and moisture present in the atmosphere. Isocyanate production data is
based on publicly available plastics data in the U.S. LCI Database.
Manufacturing
Energy Requirements. The manufacturing processes for the two cork floor products are
essentially the same. Cork waste is ground and blended with the urethane binder, then cured.
For the floating floor plank, the HDF is sandwiched between two cork sheet layers and then
cured.
Electricity and an on-site boiler are used to blend and cure both products. The boiler uses cork
powder generated during the production process to produce steam and electricity. Manufacturing
the parquet flooring requires about 0.8 MJ (0.02 kWh) of both thermal and electrical energy per
unit produced (0.09 m2, or 1 ft2); the floating floor plank requires about 1 MJ (0.28 kWh) of
electricity and 0.9 MJ (0.25 kWh) of thermal energy per unit. Water is also used in the
production process, but it is recycled and recovered by the plant. Producing each unit of product
generates about 1 kg (2.2 Ib) of waste, 94 % of which is used to produce energy and 3 % of
which is recycled. The recycled material is accounted for in the BEES life cycle inventory.
Transportation. Transportation distances for shipment of the raw materials from the suppliers to
the manufacturing plant were provided by Natural Cork. The materials were transported by
diesel truck, based on the U.S. LCI Database.
207
-------
Transportation
The finished cork products are shipped first from the manufacturing facility in Portugal to the
Natural Cork warehouse in Georgia-a distance of about 6 437 km (4 000 mi). Environmental
burdens from this leg of the journey are built into the manufacturing portion of the BEES life-
cycle inventory and are evaluated based on transport by ocean tanker using fuel oil. The
transportation distance from the Natural Cork warehouse in Augusta, Georgia to the building site
is modeled as a variable in BEES. Both products are shipped from Augusta by diesel truck; the
quantity of transportation emissions allocated to each product depends on the overall mass of the
product, as given in the Table below.
Mass per Applied Area in Density in
Cork Parquet Tile 2.56(0.51) 516.67(34.18)
7.44(1.48) 563.33(37.26)
Installation
Natural Cork parquet tile is installed using a water-based contact adhesive. The average
application requires about 0.009 kg (0.020 Ib) of adhesive per unit of flooring (0.09 m2, or 1 ft2).
The Natural Cork floating floor requires only a minimal amount of tongue-and-groove adhesive
to bond the individual planks together. On average, 5 % of the adhesive is wasted during
installation, but none of the flooring is lost.
Use
Based on information from Natural Cork, its flooring does not require replacement over the 50-
year BEES use period.
End of Life
At end of life, the used flooring is sent to a landfill, since according to the manufacturer none is
currently being recycled.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel . gov/lci/database.
PRe Consultants: SimaPro 6.0 LC A Software. 2005. The Netherlands.
Industry Contacts
Phillipe Erramuzpe, Natural Cork (2002)
208
-------
3.14 Chairs
3.14.1 Herman Miller Aeron Office Chair
Herman Miller is a worldwide producer of office furniture systems, seating, and accessories;
filing and storage products for business, home office and healthcare environments; and
residential furniture. The Herman Miller Aeron business chair consists of more than 50 different
components and subassemblies from more than 15 direct suppliers. These components and
subassemblies are constructed from four major materials: plastics, aluminum, steel, and
foams/fabrics.
The detailed environmental performance data for this product can be viewed by opening the file
E2020A.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
Herman Miller Aeron Chair
Truck _ .. , , , .1 ,
Transnnrttn » Functional Unit Of
User Chalr
I
Aero
prod
Process
T ^hair energy
uction '
Raw material
j transport
t t " t t t ' t ' t t
Glass-filled
PP ABS PET pEj
Recycled Primary Stainless
Ny|on Steel Steel Steel
t
Acetal Glass fiber
Recycled
Zmc Aluminum
Figure 3.48: Herman Miller Aeron Chair System Boundaries
Raw Materials
Approximately 60 % of the Aeron chair, by mass fraction, is comprised of recycled materials
including steel, polypropylene, glass-filled nylon, 30 % glass-filled PET, and aluminum. The
mixture of all the chair constituents in terms of their mass fractions is provided in the Table
below.
209
-------
_
Constituent_ Description
27 % for all plastics (24 % for seat and back frame
Plastics assemblies, 9 % for knobs, levers, bushings,
covers)
... 35 % for aluminum base, swing arms, seat links,
Aluminum . &
arm yokes
„ . 23.5 % for tilt assembly, 2 % for nuts, bolts, other
components
Foam/fabric (arm Less than 4 %; Pellicle seat & back suspension
rests, lumbar system is a combination of synthetic fibers and
supports) elastomers
Composite 3 % for 5 casters; 6.7 % for pneumatic cylinder;
Of the plastics and metals in the Aeron chair that are nonrenewable, over two-thirds are made
from recycled materials and can be further recycled at end of life.
Plastic components. Roughly one-fourth (27 %) of the Aeron chair, by mass fraction, is made up
of various plastic resin materials including polypropylene, ABS, PET, nylon, and glass-filled
nylons. The seat and back frame assemblies make up 23.6 % of the chair's weight. The seat and
back frames are made of glass-filled PET, two thirds of which consists of post-industrial
recycled materials. The plastic in the Pellicle suspension system (approximately 2 % of the chair
weight) can be removed for replacement or for recycling of the seat and back frames. The
remaining plastic components are various knobs, levers, bushings, and covers.
According to the manufacturer, these single-material plastic components used in the Aeron chair
are identified with International Organisation for Standardization (ISO) recycling symbols and
ASTM, International material designations to help channel them into the recycling stream.
Data for production of the plastic components comes from American Chemistry Council 2006
data developed for submission to the U.S. LCI Database.
Aluminum. Roughly 35 % of the Aeron chair is made from aluminum. Major components
include the base, swing arms, seat links, and arm yokes. Aluminum components from the Aeron
chair at the end of its life can be segregated and entered back into the recycling stream to be
made into the same or other components, so they can be considered part of a closed-loop
recycling system.
All aluminum components are made from 100 % post-consumer recycled aluminum, for which
production data is found in the U.S. LCI Database.
Steel. The tilt assembly, approximately 23.5 % of the chair's weight, is largely made up of steel
stampings and screw-machined components. These steel components represent 74 % of the tilt,
by mass fraction, or 17.3 % of the mass of the chair. From 7 % to 50 % of the steel components
210
-------
in the tilt are made from recycled materials. The remaining steel materials (less than 2 % of the
chair) are nuts, bolts, and other components that require the high strength properties of steel.
Production of primary and secondary steel is based on LCI data submitted by the American Iron
and Steel Institute (AISI) and the International Iron and Steel Institute (IISI), which represents
late 1990s worldwide steel production.
Foam/Fabric. The armrests and lumbar supports are the only Aeron chair components made
from foams or fabrics. The Pellicle seat and back suspension system is a combination of
synthetic fibers and elastomers and comprises a small percentage of the chair. Fabric scraps
from Herman Miller's production facilities are recycled into automobile headliners and other
similar components. Foam scraps are recycled into carpet padding. Data on synthetic fibers and
elastomers comes from elements of the U.S. LCI Database and the SimaPro database.
Composite Subassemblies. The Aeron chair has three composite subassemblies of multiple
material types. They consist of five casters, a pneumatic cylinder, and the moving components of
the tilt assembly. The pneumatic cylinder can be returned to the manufacturer for disassembly
and recycling. All material production data is based on elements of the U.S. LCI Database and
the SimaPro database.
Manufacturing
Energy requirements and emissions from chair assembly are included in the model but not
shared to protect company-specific confidential data. The energy used for processes that form
materials into chair parts (plastic extrusion, steel rolling and stamping, etc.) is included in the
product data for the raw materials acquisition life cycle stage.
Transportation
Packaging materials for the Herman Miller Aeron chair include corrugated paper and a
polyethylene plastic bag to protect the product from soiling and dust. Each of these materials is
part of a closed-loop recycling system. As such, they are not included in the system boundaries.
On larger shipments within North America, disposable packaging can be eliminated through use
of reusable shipping blankets.
Transportation of the chair by heavy-duty truck to the building is modeled as a variable of the
BEES system. Data on diesel trucking is based on the U.S. LCI Database.
Use
The plastics in the chair are low-VOC emitting and most painted parts are powder-coated. The
small amounts of foam and fabric are insignificant contributors of VOC.
End of Life
The Herman Miller Aeron chair is designed to last at least 12.5 years under normal use
conditions, so the chair is assumed to be replaced three times over the 50-year BEES use period.
As with all BEES products, life cycle environmental burdens from these replacements are
included in the inventory data.
211
-------
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
http://www.hermanmiller.com.
Industry Contacts
Gabe Wing, Herman Miller (2001)
3.14.2 Herman Miller Ambi and Generic Office Chairs
Herman Miller is a worldwide producer of office furniture systems, seating, and accessories;
filing and storage products for business, home office, and healthcare environments; and
residential furniture. The Herman Miller Ambi chair is typical of the industry average office
chair, and is used in BEES to represent both itself and a generic office chair.
The detailed environmental performance data for both these products can be viewed by opening
the file E2020B.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
Herman Miller Ambi Chair
Truck ,_ .. ,,,.!,
Transport to -» Funohonal Unrtof
User Chalr
I
Amb
prod
i
Process
^hair energy
uction ^
Raw material
t t " t t t ' t t t
Glass-filled
PP ABS PET PET
Recycled Primary Stainless
Ny|on Steel Steel Steel
t
Acetal Glass fiber
Zinc
Figure 3.49: Herman Miller Ambi Chair System Boundaries
212
-------
Raw Materials
The Herman Miller Ambi chair consists of more than 50 different components and
subassemblies from more than 15 direct suppliers. The components and subassemblies are
constructed from variations of three major materials: plastics, steel, and foams/fabrics.
Approximately 20 % of the Ambi chair's weight is made up of recycled steel, polypropylene,
nylon, and glass-filled nylon. The mixture of all the constituents in terms of their mass fractions
is given in the Table below.
Constituent
Plastics (PP, PVC, nylon, 33 % for all plastics (24 % for seat shells, 9 % for
glass-filled polymer) knobs, levers, bushings, covers)
Steel 63 % for tilt assembly and base; 2 % for nuts, bolts,
other components
Foams/fabrics Less than 4 %; included in open-loop recycling
systems
Composite subassemblies 3 % for five casters; 6.7 % for pneumatic cylinder;
6.3 %J
-------
production facilities are made into automobile headliners and other similar products. Foam
scraps are used in carpet padding.
Composite Subassemblies. There are three composite subassemblies of multiple material types.
They include five casters (3 % of the chair mass), a pneumatic cylinder (6.7 % of the chair
mass), and the moving components of the tilt assembly (6.3 % of the chair mass). The
pneumatic cylinder can be returned to the manufacturer for disassembly and recycling. All
material production data is based on elements of the U.S. LCI Database and the SimaPro
database.
Manufacturing
Energy requirements and emissions from chair assembly are included in the model but not
shared to protect company-specific confidential data. The energy used for processes that form
materials into chair parts (plastic extrusion, steel rolling and stamping, etc.) is included in the
product data for the raw materials acquisition life cycle stage.
Transportation
Packaging materials for the Herman Miller Ambi chair include corrugated paper and a
polyethylene plastic bag to protect the product from soiling and dust. Each of these materials is
part of a closed-loop recycling system. As such, they are not included in the system boundaries.
On larger shipments within North America, disposable packaging can be eliminated through use
of reusable shipping blankets.
Transportation of the chair by heavy-duty truck to the building is modeled as a variable of the
BEES system. Data on diesel trucking is based on the U.S. LCI Database.
Use
The chair is designed for easy maintenance, with many replaceable components. For BEES,
however, no parts replacement is assumed; instead, the entire chair is simply replaced at end of
life (see End of Life section below).
The plastics in the chair are low-VOC emitting and most painted parts are powder-coated. The
small amounts of foam and fabric are insignificant contributors of VOC.
End of Life
The Herman Miller Ambi chair is designed to last at least 12.5 years under normal use
conditions. Thus, the chair is assumed to be replaced three times over the 50-year BEES use
period. As with all BEES products, life cycle environmental burdens from these replacements are
included in the inventory data.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
http://www.hermanmiller.com
214
-------
Industry Contacts
Gabe Wing, Herman Miller (2001)
3.15 Roadway Dust Control
3.15.1 Environmental Dust Control Dustlock
The roadway dust suppressant category includes products aimed at eliminating or reducing the
spread of dust associated with gravel roads and other sources of high dust levels such as
construction. Dustlock, produced by Environmental Dust Control, Inc. in Minnesota, is a
biobased dust suppressant produced from by-products of the vegetable oil refining process.
When applied, Dustlock penetrates into the bed of the material generating the dust and "bonds"
to make a barrier that is naturally biodegradable. The bond keeps Dustlock in place, preventing
the exposure of any material underneath. The manufacturer reports that Dustlock also reduces
erosion of surface material (e.g., gravel) and the appearance of mud.
The functional unit for this category in BEES is dust control for 92.9 m2 (1 000 ft2) of surface
area. One gal of Dustlock covers approximately 3.4 m2 (37 ft2), so 102 L (27 gal) of Dustlock
are modeled for the BEES application.
The detailed environmental performance data for this product may be viewed by opening the file
G2015B.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
215
-------
Environmental Dust ControlDustlock
1
Acidulated
soapstock
production
Linseed
distillate
productio
Figure 3.50: Dustlock System Boundaries
Raw Materials
Dustlock is comprised of acidulated soapstock and linseed distillate. The acidulated soapstock
may be any combination of sunflower, canola, or soybean soapstock. Since BEES data for
soybean production and processing is the most comprehensive, soybean-based soapstock is
modeled for this product. Acidulated soapstock is a co-product of the soybean crushing process
involved in biodiesel production; data for this process comes from biodiesel life cycle data
developed for the U.S. Department of Agriculture that was used to compare petroleum-based
diesel fuel to soy-based biodiesel.171 The allocation among biodiesel and its coproducts is mass-
based, with acidulated soapstock amounting to 0.1 % of the total output. Data for soybean
production comes from the U.S. LCI Database.
Energy requirements and emissions for linseed oil production involve fuel oil and steam, and are
allocated on an economic basis between linseed oil (87 %) and linseed cake (13 %). The
cultivation of linseed is based on a modified version of wheat production data from the U.S. LCI
Database.
171 Sheehan, J. et al, NREL/SR-580-24089 (Washington, DC: US Department of Agriculture and US
Department of Energy, May 1998).
216
-------
Manufacturing
Energy Requirements and Emissions. Electric motors and pumps are used to blend the product
and pump it in and out of tanks; these consume 1.5 J (4.3 E-4 kWh) per kg of Dustlock.
Electricity is modeled using the U.S. average electric grid from the U.S. LCI Database.
Transportation. Raw materials are transported to the manufacturing site by diesel truck:
soapstock travels 451 km (280 mi) and linseed oil 1086 km (675 mi). Diesel trucking is modeled
using the U.S. LCI Database.
Transportation
Product transport to customers is assumed to average 805 km (500 mi) by diesel truck, and is
modeled based on the U.S. LCI Database.
Installation
Dustlock requires heating before application when outside air or ground temperature is below 16
°C (60 °F) at night. For the BEES model, the heating is done with liquefied petroleum gas (LPG).
Gasoline-powered equipment is used to spray the Dustlock™ onto the surface area. The energy
requirements follow.
Energy Carrier Quantity
MJ/kg(kWMb)
Liquid petroleum gas 0.14 (0.02)
Gasoline
Dustlock is applied at a rate of 3.4 m2 (37 ft2) per gal, or 102 L (27 gal) for a 92.9 m2 (1 000 ft2)
application. At a density of 3.4 kg (7.5 Ib) per gal, 93 kg (205 Ib) of Dustlock are used for the
application.
End of Life
No end of life burdens are modeled since the product is consumed during use.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database . 2005.
Golden, CO. Found at: http://www.nrel . gov/lci/database.
PRe Consultants: SimaPro 6.0 LC A Software. 2005. The Netherlands.
Sheehan, J. et al., Life Cycle Inventory of Biodiesel and Petroleum Diesel for Use in an Urban
Bus, NREL/SR-5 80-24089 (Washington, DC: U.S. Department of Agriculture and U.S.
Department of Energy, May 1998).
Industry Contacts
Howard Hamilton (2005)
217
-------
3.16 Parking Lot Paving
3.16.1 Generic Concrete Paving
Portland cement concrete, typically referred to as "concrete," is a mixture of portland cement (a
fine powder), water, fine aggregate such as sand or finely crushed rock, and coarse aggregate
such as gravel or crushed rock. The semi-fluid mixture forms a rock-like material when it
hardens. Fly ash—a waste material—may be substituted for a portion of the portland cement in
the concrete mix.
Concrete is specified for different building elements by its compressive strength measured 28
days after casting. Concretes with greater compressive strengths generally contain more
cementitious materials. For the BEES concrete paving alternatives, a compressive strength of at
least 24 MPa (3 500 lb/in2) is used. The concrete paving systems all consist of a 15 cm (6 in)
layer of concrete poured over a 20 cm (8 in) base layer of crushed stone or compacted sand.
Paving installed in regions that experience freezing conditions have intentionally entrained air to
the volume of 4 % to 6 % to improve its durability in these conditions.
For 0.09 m2 (1 ft2) of concrete paving, the 15 cm (6 in) thick concrete layer weighs 32.9 kg (72.5
Ib) and the 20 cm (8 in) thick crushed stone base layer weighs 33.3 kg (73.3 Ib). Fly ash, a waste
material that results from burning coal to produce electricity, can be substituted in equal
quantities by mass for various proportions of the cement.
The detailed environmental performance data for three generic concrete paving alternatives may
be viewed by opening the following files under the File/Open menu item in the BEES software:
• G2022A.DBF—100 % Portland Cement for Parking Lot Paving
• G2022B.DBF—15 % Fly Ash Cement for Parking Lot Paving
• G2022C.DBF—20 % Fly Ash Cement for Parking Lot Paving
Flow Diagram
The flow diagram below shows the major elements of the production of concrete paving for
these products, as they are currently modeled for BEES.
218
-------
Concrete Paving
Transport to
Paving Site
^
Functional Unit of
Paved Concrete
End-of-Life
i
Fine Aggregate
Production
Water
, L
Concrete
Production
t i *
I
Coarse
Aggregate
Production
Portland
Cement
Production
Process
Energy
Raw Material
Transport
t
t 1
Stone
Base
Production
F
(0%,
Figure 3.54: Concrete Paving System Boundaries
Raw Materials
The Table below shows concrete constituents and their quantities for the compressive strength of
24 MPa (3 500 lb/in2).
Table 3.115: Concrete Constituents
Constituent
Portland Cement and Fly Ash
Coarse Aggregate
Fine Aggregate
Water
Kg/m3
(Ib/yd3)
265(450)
1070(1800)
710(1200)
180(300)
Mass Fraction
12%
42%
38%
In LCA terms, fly ash is an environmental outflow of coal combustion, and an environmental
inflow of concrete production. As such, this waste product is considered an environmentally
"free" input material.172 Transport of the fly ash to the ready mix plant, however, should be—and
is—included in the BEES model.
A small amount of coarse aggregate and sand, assumed to be approximately 3 %, is recycled
from unused returned concrete. Process water from concrete manufacturing (post-industrial) and
in some cases post-consumer water also may be used as a component in concrete.
The environmental burdens associated with the production of waste materials are typically allocated to the
intended product(s) of the process from which the waste results.
219
-------
Manufacturing
Energy Requirements and Emissions. For concrete paving, about 20 % of the concrete is
produced in central ready mix operations. Energy use in the batch plants includes electricity and
fuel used for heating and mobile equipment.173
Table 3.116: Energy_ Re^uirements_for_ Readg Muc Concrete^ Production
~Ener^iCarrj^"~~ ~IjJ/t^^
____________ oTo?(22)
Electricity 124 (0.09) 0.05 (22)
Most concrete for paving applications (80 %) is produced in dry batch operations where the
constituents are placed in a truck mixer. Concrete producers are located in all regions of the
country since the product has to be placed within 1 h driving time from the production location.
The trucks consume one gal of diesel fuel for every 5 km to 6 km (3 mi to 4 mi) traveled, and
travel on average 64 km/h (40 mi/h) to reach the site. The fuel usage for mixing concrete in a
truck mixer is estimated at 30 % of the total fuel used by mixer trucks.
Tabl£ 3.112; Energy Re^uirements^^or^ Z)ry Batch Concrete^ Production^
Energy^ Carrier^ L/™3 (K^I^l ^^K (§a!/iPJ
_______ __.__ ___„____
Diesel Oil for Mixing (30 %) 2.12 (0.429) 0.00095 (0.00011)
Transportation. Concrete raw materials are transported to a plant where they are batched into
either a plant mixer or a truck mixer. Round-trip distances by truck for the transport of the
materials are assumed to be 97 km (60 mi) for portland cement and fly ash and 80 km (50 mi) for
aggregate.
Waste. There is no manufacturing waste for either of the concrete manufacturing processes.
Transportation
The distance for transportation of concrete paving materials by heavy-duty truck to the building
site is modeled as a variable of the BEES system.
173 Nisbet, M, et al. "Environmental Life Cycle Inventory of Portland Cement Concrete." PCA R&D Serial No.
2737a(Skokie, IL: Portland Cement Association, 2002).
220
-------
Installation
The energy required for site preparation and placement of crushed stone is 7.5 MJ/m2 (663
Btu/ft2) of paving. The energy required for concrete placement is included in the energy
requirements for the mixer truck that transports the concrete to the site.
About 3 % to 5 % of the total production of paving concrete is unused at the job site and returned
to the concrete plant. Some of this material is recycled back into the product, and supplementary
products also are developed. In some cases, the returned concrete is washed into pits and the
settled solids are reused for other purposes or diverted to landfills. Landfill usage is minimized
due to cost. For the purpose of this generic model of concrete paving, it is most representative of
current practice to assume that 75 % of the leftover concrete is recycled back into the product as
aggregate and 25 % is reused for other purposes. Industry practice varies based on local
regulations, plant space, and company policy.
Installation of concrete paving on roadways requires heavy equipment using heavy fuel at 0.7
MJ (0.19 kWh) of fuel per ft2 of paving; however, use of heavy equipment for installation may
not be required for applications such as parking areas and sidewalks. Paving of larger parking
areas like a mall area (generally totaling greater than 929 m2, or 10 000 ft2) requires some power-
driven equipment with screeds174 and ride-on finishing machines. The fuel used is some
combination of diesel and gasoline, although only diesel fuel is assumed for modeling purposes.
A rough estimate of fuel usage is about 20 % of that used for road paving. Smaller area
placements (totaling less than 929 m2, or 10 000 ft2) are done manually with hand tools.
As noted above, unused concrete is usually returned to the concrete plant. About 1 % waste is
generated on site as poured waste or spillage. This concrete is not returned to the mixer truck but
is collected and hauled to the landfill with other construction debris.
Use
The design life for concrete pavement is typically 30 years, although longer life designs are now
being promoted. Maintenance requirements are not intensive relative to life-cycle energy and
other environmental burdens.
End of Life
At end of life, concrete parking lot paving is typically overlaid rather than replaced if the land is
going to remain in use as a parking lot. The concrete is generally removed if the land is going to
be used for a different purpose.
If the concrete paving is removed, the material can be crushed and reused on site or transported
for use in another fill application. The decision to send crushed concrete to a landfill is a project
decision. It is most representative of current practice to assume that removed concrete is
managed by crushing and reusing or recycling in some manner other than landfilling.
174 Screeds are used to level poured concrete surfaces.
221
-------
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0LCA Software. 2005. The Netherlands.
Nisbet, M., et al. "Environmental Life Cycle Inventory of Portland Cement Concrete." PCA
R&D Serial No. 2137a, (Skokie, IL: Portland Cement Association, 2002).
Industry Contacts
Colin Lobo, Ph.D., P.E, Vice President of Engineering, National Ready Mixed Concrete
Association, September-October 2005.
3.16.2 Asphalt with GSB88 Seal-Bind Maintenance
The design of an asphalt parking lot pavement is dependent on the projected weight of traffic,
the soil conditions at the site, and environmental conditions. Common asphalt parking lots
consist of between 5 cm and 10 cm (2 in and 4 in) thick Hot-Mix Asphalt (HMA), which
contains, on average, 15 % Recycled Asphalt Pavement (RAP). RAP is obtained from the
millings of HMA surface lots or roadways and is typically hauled back to the HMA plant for
reuse. The HMA pavement material is typically placed over a 15 cm (6 in) crushed aggregate
base. In colder climates, additional fill material that insulates against frost-susceptible soils may
be added below the base aggregate. The maintenance product assessed for this BEES paving
alternative is GSB88 Emulsified Sealer-Binder produced by Asphalt Systems, Inc. of Salt Lake
City, Utah. GSB88 Emulsified Sealer-Binder is a high-resin-content emulsifier made from
naturally occurring asphalt and is applied to base asphalt every four years to prevent oxidation
and cracking.
For the BEES asphalt parking lot model, a 0.09 m2 (1 ft2) surface with 8 cm (3 in) thick paving is
studied. The amount of material used is 16.4 kg (36.2 Ib) of HMA, 30.6 kg (67.5 Ib) of crushed
stone, and 12 installments of the GSB88 sealer-binder, at 0.374 kg (0.82 Ib) each, over 50 years.
The detailed environmental performance data for this product system may be viewed by opening
the file G2022D.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product system as it
is currently modeled for BEES.
222
-------
Asphalt Paving with GSB88 Emulsion Maintenance
Figure 3.52: Asphalt Paving with GSB88 Emulsified Sealer-Binder Maintenance System
Boundaries
Raw Materials
The composition of asphalt paving is shown in the Table below, and the production of its raw
materials is based on data from both the U.S. LCI Database and the SimaPro database. The 15 %
RAP in HMA reduces virgin asphalt binder requirements (by approximately 1 %) and reduces
crushed stone (aggregate) amounts by approximately 14 %. The emulsifier is composed of
asphalt with water and a small amount of surfactant.
Table 3.118: Hot Mix Asphalt Constituents
Constituent
Mass Fraction
(layer)
Mass Fraction
(components)
Hot Mix Asphalt 99.5 %
Gravel
Asphalt
binder
RAP
Tack Coat 0.5 %
Asphalt
Water
Emulsifier
HC1
81%
4%
15%
—
66%
33%
1.1%
0.2 %
223
-------
Raw materials used in the GSB88 sealer-binder include water, asphalt, sand, light fuel oil,
175
detergent, emulsifier, and hydrochloric acid (HC1). These materials, too, are based on data
from the U.S. LCI Database and the SimaPro database.
Manufacturing
Energy Requirements and Emissions. The energy requirements for HMA production are
provided in the Table below, and represent a weighted average of requirements for production in
counterflow drum (85 %) and batch mix (15 %) plants.
Table 3. 119: Energy_ Requirements for Ho£ Mix Asghal£ Production
Energy^ Carrier MJ/kg_ (BtuAb}
_____ _____ ...................
Natural Gas 0.29 (124.7)
JI<^
Emissions from the production of the upstream, or raw, materials and energy carriers are from
the U.S. LCI Database. Emissions associated with the manufacture of asphalt are based on U.S.
EPA AP-42 emission factors. The primary emissions from HMA production are particulates
(PM) and volatile organic compounds (VOC); these are averaged on a weighted basis between
counterflow drum (85 %) and batch mix (15 %) production technologies, as shown below.
Table 3. 120: Enussionsjrom Hot Mix Asghalt^ Production
Production Process PM VOC
g/kg (lb/ton) g/kg (lb/ton)
_________ ............................................ 5707(014)" 0^16(5^32)"
Batch Mix 0.0225 (0.45) 0.0041 (0.0082)
Transportation. Transport of the HMA raw materials to the production site is accomplished by
trucking, over an average distance of 48 km (30 mi).
Waste. The manufacturing process generates no waste materials as all materials are utilized in
the HMA pavement.
Transportation
Transport of HMA by heavy-duty truck to the construction site is modeled as a variable of the
BEES system.
Installation
New asphalt pavements are placed directly on graded and compacted aggregate base or
subgrade. A truck carrying HMA paving material from the plant backs up to a paver and dumps
175 Detailed information on product composition is not provided to protect manufacturer confidentiality.
224
-------
the material into a hopper or a material transfer vehicle, which agitates the asphalt mix to keep
the aggregate from segregating and to help ensure a uniform temperature. The paver lays a
smooth mat of material, then a series of compactors make the material more dense. These
compactors may include vibratory or static steel wheel rollers or rubber tire rollers. If multiple
layers are placed or the parking lot is overlaid, the pavement surface is cleaned (typically by
brooming) and then a distributor truck puts down a tack coat. The energy requirements for
installation of an asphalt parking lot are provided in the following Table, with all diesel data
based on the U.S. LCI Database.
Table 3. 121_: Energy ^ajiireinents_ifor_ Asphalt Pavetnent_ Installation
Installation Process Energy^ Carrier^ MJ/ff_
Site Preparation and Stone Base _ . . _ . n 7
_., ^ Diesel Equipment u- '
Placement
Asphalt Binder Course Installation Diesel Equipment 0.96
Asphalt Wearing Course Installation Diesel Equipment 0-48
IIIIIIII~
Use
Asphalt parking lot pavement is assumed to have a useful life of at least 50 years with
application of GSB88 sealer-binder maintenance every 4 years. The energy required for each
maintenance application is provided in the following Table.
Table_ 3.122: Energy ESM—l— ——,,£— ———, §——~
Maintenance Process_ Energy^ Carrier^
GSB88 Sealer-Binder Application Diesel Equipment 9.45 E-4
End of Life
At end of life, asphalt paving is typically overlaid rather than replaced if the land is going to
remain in use as a parking lot. The HMA is generally removed and recycled, however, if the land
is going to be used for a different purpose. For BEES, the product is removed at end of life.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel . gov/lci/database.
PRe Consultants: SimaPro 6.0 LC A Software. 2005. The Netherlands.
U.S. Environmental Protection Agency, "Hot Mix Asphalt Plants, " Volume I: Section 11.1,
AP-42: Compilation of Air Pollutant Emission Factors, (Washington, DC: U.S.
Environmental Protection Agency, April 2004). Found at:
http://www.epa.gov/ttn/chief/ap42/chl 1/fmal/cl IsOl.pdf.
Industry Contacts
Howard Marks, Director of Regulatory Affairs, National Asphalt Paving Association (2005)
Mr. Gail Porritt, Asphalt Systems, Inc. (2002)
225
-------
3.16.3 Generic Asphalt with Traditional Maintenance
The design of an asphalt parking lot pavement is dependent on the projected weight of traffic,
the soil conditions at the site, and environmental conditions. Common asphalt parking lots
consist of between 5 cm and 10 cm (2 in and 4 in) thick Hot-Mix Asphalt (HMA), which
contains, on average, 15 % Recycled Asphalt Pavement (RAP). RAP is obtained from the
millings of HMA surface lots or roadways and is typically hauled back to the HMA plant for
reuse. The HMA pavement material is typically placed over a 15 cm (6 in) crushed aggregate
base. In colder climates, additional fill material that insulates against frost-susceptible soils may
be added below the base aggregate. Maintenance of asphalt parking lots, over 50 years, typically
involves a 3.8 cm (1.5 in) HMA overlay with tack coat at year 15 followed by a 3.8 cm (1.5 in)
mill and HMA overlay with tack coat every subsequent 15 years. Each maintenance coat
contains, on average, 15 % RAP.
For the BEES asphalt parking lot model, a 0.09 m2 (1 ft2) surface with 8 cm (3 in) thick paving is
studied. The amounts of materials used are 16.4 kg (36.2 Ib) of HMA, 30.6 kg (67.5 Ib) of
crushed stone, and 3 installments of the HMA maintenance at 7.7 kg (17.0 Ib) each.
The detailed environmental performance data for this product system may be viewed by opening
the file G2022E.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product system as it
is currently modeled for BEES.
Asphalt Paving and Maintenance
Tack Coat
Asphalt
Production
Hot Mix
Asphalt
Emulsifier
Production
Asphalt
Production
Emu
Prod
sifier
jction
Figure 3.53: Asphalt Paving with Traditional Maintenance System Boundaries
226
-------
Raw Materials
The composition of asphalt paving is shown in the Table below. The production of the raw
materials required for both the pavement and its maintenance is based on data from both the U.S.
LCI Database and the SimaPro database. The 15 % RAP in HMA reduces virgin asphalt binder
use (by approximately 1 %) and reduces crushed stone (aggregate) amounts by approximately
14 %. The emulsifier is composed of asphalt with water and a small amount of surfactant.
Table 3.123_: Hot Mw Asj)halt_ Constituent^
Constituent Mass Fraction Mass Fraction
(Ial'?rl (components^
Hot Mix Asphalt 99.5 %
Gravel
Asphalt
binder
RAP
Tack Coat 0.5 %
Asphalt
Water
Emulsifier
HC1
81 %
4%
15%
—
66%
33%
1.1%
0.2 %
Manufacturing
Energy Requirements and Emissions. The energy requirements for HMA production are
provided in the Table below, and represent a weighted average of requirements for production in
counterflow drum (85 %) and batch mix (15 %) plants.
Table 3. 124: Energy Rejuir^mjznts^or Hot_ Mix Asphal
Energy^ Carrier^ MJ/kg_ (Btu/lb}
___. 0017C73)
Natural Gas 0.29 (124.7)
Emissions from the production of the upstream (raw) materials and energy carriers are from the
U.S. LCI Database. Emissions associated with the manufacture of asphalt are based on U.S. EPA
AP-42 emission factors. The primary emissions from HMA production are particulates (PM)
and volatile organic compounds (VOC); these are averaged on a weighted basis between
counterflow drum (85 %) and batch mix (15 %) production technologies, as shown below.
Table_ 3. 125: Emissions_£r£m Hot_ Mjx Asphalt ^ Production
Production "Process "PM VOC
S/kg. (tb/ton)_ g/kg_ (Vb/ton)
_________ 007(014) 0^016(0032)"
Batch Mix 0.0225 (0.45) 0.0041 (0.0082)
227
-------
Transportation. Transport of the HMA raw materials to the production site is accomplished by
trucking, over an average distance of 48 km (30 mi).
Waste. The manufacturing process generates no waste materials as all materials are utilized in
the HMA pavement.
Transportation
Transport of HMA to the construction site by heavy-duty truck is modeled as a variable of the
BEES system.
Installation
New asphalt pavements are placed directly on graded and compacted aggregate base or
subgrade. A truck carrying HMA paving material from the plant backs up to a paver and dumps
the material into a hopper or a material transfer vehicle, which agitates the asphalt mix to keep
the aggregate from segregating and to help ensure a uniform temperature. The paver lays a
smooth mat of material, then a series of compactors make the material more dense. These
compactors may include vibratory or static steel wheel rollers or rubber tire rollers. If multiple
layers are placed or the parking lot is overlaid, the pavement surface is cleaned (typically by
brooming) and then a distributor truck puts down a tack coat. The energy requirements for
installation of an asphalt parking lot are provided in the following Table, with all diesel data
based on the U.S. LCI Database.
.126: Energy Requirements for^As£halt_ Paving^ Installation
Installation Process Energy Carrier^ MJ/ff_
Site Preparation and Stone Base _ . . ^ n 7
_, Diesel equipment u- '
Placement
Asphalt Binder Course Installation Diesel equipment 0-96
Asphalt Wearing Course Installation Diesel equipment 0.48
Use
The asphalt parking lot pavement is assumed to have a useful life of greater than 50 years with
maintenance performed every 15 years. The maintenance of the parking lot with HMA is called
resurfacing. The surface is cleaned and all unnecessary debris is removed. A tack coat is then
applied by a distributor truck. Hot asphalt is then applied and compacted. The energy required
for resurfacing is provided in the following Table.
Table 3.127: Energy Rejjmn:tnentsJwAs£hal£ Resurfacing
Maintenance Process Energy Carrier^
Asphalt Resurfacing Diesel equipment O-7^
After the initial resurfacing at year 15, all subsequent resurfacings begin with removal of 3.8 cm
(1.5 in) of existing material, followed by an HMA overlay with tack coat containing, on average,
228
-------
15 % RAP. The 3.8 cm (1.5 in) of milled material is returned to the HMA manufacturing process
as RAP.
End of Life
At end of life, the product is typically overlaid rather than replaced if the land is going to remain
in use as a parking lot. However, the HMA is generally removed and recycled if the land is going
to be used for a different purpose.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
U.S. Environmental Protection Agency, "Hot Mix Asphalt Plants, " Volume I: Section 11.1,
AP-42: Compilation of Air Pollutant Emission Factors, (Washington, DC: U.S.
Environmental Protection Agency, April 2004). Found at:
http://www.epa.gov/ttn/chief/ap42/chl 1/final/cl IsOl.pdf.
Industry Contacts
Howard Marks, Director of Regulatory Affairs, National Asphalt Paving Association (2005)
3.16.4 Lafarge Cement Concrete Paving
See documentation on all BEES Lafarge concrete products under Lafarge North America
Products.
3.17 Fertilizers
3.17.1 Perdue MicroStart 60 Fertilizer
Perdue AgriRecycle's MicroStart 60™ is a slow-release nitrogen fertilizer consisting almost
entirely of chicken litter, a byproduct of the poultry industry. Its Nitrogen-Phosphorus-
Potassium (NPK) ratio is 4-2-3.
For the BEES system, the functional unit for fertilizers is applying 10 kg (22 Ib) nitrogen per
acre for a period often years. A typical application of MicroStart 60™ is 318 kg (700 Ib) per
acre. As the nitrogen in one application is released over a period of three years, fertilizer use per
acre, per year, is 106 kg (233 Ib). To achieve a 10 kg (22 Ib) nitrogen per acre requirement,
however, this amount is scaled up to 245 kg (540 Ib) of fertilizer per acre per year.176
The detailed environmental performance data for this product may be viewed by opening the file
G2060A.DBF under the File/Open menu item in the BEES software.
176 While this may not be the manufacturer's suggested rate of use for this product, an adjustment was made to
enable comparison of BEES fertilizers on a functionally equivalent performance basis.
229
-------
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
MicroStart 60 Fertilizer
Poultry litter
production
Poultry fat
production
Figure 3.54: MicroStart 60™ Fertilizer System Boundaries
Raw Materials
Microstart 60 is composed of raw poultry litter and poultry fat, in the proportions shown in the
Table below.
Table 3.128: Microstart 60 Constituents
Constituent
Mass Fraction (%)
Raw poultry litter
Poultry fat
99.9
0.1
The raw poultry litter is a byproduct of the poultry industry and would otherwise be a waste
product. Therefore, any impacts associated with its production, such as chicken farming and
poultry production, are allocated to the production of the poultry, not the litter. Wastewater
generation from poultry production processes is accounted for in the context of poultry fat
production; poultry fat accounts for 0.1 % of the inputs to these processes.177
Manufacturing
Energy Requirements and Emissions. Electricity and #2 diesel oil for a generator are among
the energy requirements for manufacturing. Steam is generated from a 74.6 kW (100 hp) boiler,
for palletizing and heating the finished product, for use of a scrubber, and for dust control.
Approximately 472 MJ (131 kWh) and 0.04 m3 (10 gal) of diesel are required to produce one ton
177 World Bank Group, "Meat Processing and Rendering," (World Bank, July 1998). Found at:
http://lnwebl8.worldbank.org/essd/essd.nsf/GlobalView/PP AH/$File/65_meat.pdf.
230
-------
(2 000 Ib) of fertilizer. Electricity is modeled using the U.S. average electric grid from the U.S.
LCI Database. Diesel fuel production data comes from the U.S. LCI Database, as does a portion
of the data used to represent its combustion in a boiler. Data for some of the diesel emissions is
provided directly by Perdue AgriRecycle, and is included in the BEES model as follows.
Table 3.129: Microstart 60 Manufacturinj*_Ernissions
Air Emission S/^KJ(ii^ion)
Nitrogen Oxides 1.24 (2.48)
Carbon Dioxide 1.61(3.21)
Sulfur Dioxide 1.61(3.21)
Particulates (unspecified) 1.23 (2.45)
mmonia
Transportation. The raw litter is transported an average of 120 km (75 mi) and the poultry fat
161 km (100 mi) to Perdue AgriRecycle 's facility.
Water Effluents. About 10 tanker loads of water effluents per week are generated from
manufacturing Microstart 60™. However, this water is beneficially applied on land for
irrigation, so is not modeled as a wastewater or as specific water effluents.
Transportation
Truck and rail are both used to ship Microstart 60™ to customers located across the United
States. The transportation distance is modeled as a variable of the BEES system, with burdens
shared equally by truck and rail.
Installation
Any burdens that may arise from on-site application of fertilizer are not accounted for in BEES.
Use
The nitrogen in the fertilizer is released over a three-year period. Microstart 60™ is fully
biodegradable.
End of Life
There are no end of life burdens for this product since it is fully consumed during use,
eliminating the need for waste management.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel . gov/lci/database.
World Bank Group, "Meat Processing and Rendering," Pollution Prevention and Abatement
Handbook (World Bank, July 1998). Found at:
http://lnweb 1 8.worldbank.org/essd/essd.nsf/GlobalView/PPAH/$File/65 meat.pdf
Industry Contacts
Joe Koch, Perdue AgriRecycle (2005)
231
-------
3.17.2 Four All Seasons Fertilizer
Four All Seasons is a fertilizer composed of corn products, soybean products, and animal by-
products with a Nitrogen-Phosphorus-Potassium (NPK) ratio of 10-1-1. According to the
manufacturer, it can be used as a substitute for certain petroleum-based fertilizers: for every two
applications of the petroleum-based product, only one application of Four All Seasons is
necessary.
For the BEES system, the functional unit for fertilizers is applying 10 kg (22 Ib) nitrogen per
acre for a period often years. A typical application of Four All Seasons is approximately 489 kg
per hectare (436 Ib per acre). Since nitrogen continues to be released in the second year,
fertilizer use per acre, per year, is 132 kg (290 Ib), assuming the application lasts 1.5 years. To
achieve a 10 kg (22 Ib) nitrogen per acre requirement, however, this amount is scaled down to
100 kg (220 Ib) of fertilizer per acre per year.178
The detailed environmental performance data for this product may be viewed by opening the file
G2060B.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
178 While this may not be the manufacturer's suggested rate of use for this product, an adjustment was made to
enable comparison of BEES fertilizers on a functionally equivalent performance basis.
232
-------
Four All Seasons Fertilizer
Truck
Transpor
sit
1
Blood meal
production
Per
proc
fc Functional Unit of
tto * ,_ ....
Fertilizer
^ L
Four All
Seasons
Production
t
1
Soybean Dried distille
meal grain
production production
t +
1
Soybean
Production
T
ilizer Agrichemicals
uction production p
Process
Energy
Raw Material
transport
r Corn syrup
production
f
1
Corn
Production
T
=ertilizer Agric
reduction pro
~l
hemicals
duction
Figure 3.55: Four All Seasons Fertilizer System Boundaries
Raw Materials
Four All Seasons is composed of several animal- and vegetable-based products and byproducts.
Animal blood meal. Production of animal blood meal is based on European data for
slaughterhouse residue production.179
Dry distiller grain. Production of this product constituent is based on the dry milling process, in
which the grain is a coproduct of ethanol. Various sources are used to generate data for the dry
milling process.180
Corn syrup. This constituent is based on wet milling processes, and modeled with data from
several sources.181
Soybean meal. Data for this product constituent is based on data from the National Renewable
179 Nielsen, H., 2.-0 LCA Consultants, July 2003. Found at: http://www.lcafood.dk.
180 Graboski, Michael S., (National Corn Growers Association, August 2002); Shapouri, H., "The 2001 Net
Energy Balance of Corn-Ethanol" (U.S. Department of Agriculture, 2004); U.S. Environmental Protection Agency,
"Grain Elevators and Processes, " Volume I: Section 9.9.1, AP-42: Compilation of Air Pollutant Emission Factors
(Washington, DC: US Environmental Protection Agency, May 2003). Found at:
http://www.epa.gov/ttn/chief/ap42/ch09/final/c9s0909-l.pdf.
181 Galitsky, C., Worrell, E., and Ruth, M., LBNL-52307 (Ernest Orlando Lawrence Berkeley National
Laboratory, July 2003); U.S. Environmental Protection Agency, "Corn Wet Milling," Volume I: Section 9.9.7, AP-
42: Compilation of Air Pollutant Emission Factors (Washington, DC: US Environmental Protection Agency,
January 1995). Found at: http://www.epa.gov/ttn/chief/ap42/ch09/final/c9s09-7.pdf.
233
-------
Energy Laboratory's (NREL's) LCA study of biodiesel use in an urban bus.182
Manufacturing
Energy Requirements and Emissions. Electricity and steam are used to produce Four All
Seasons fertilizer. Four All Seasons provided site data for the amount of each in dollars per ton
of fertilizer produced. The Table below translates this data into energy requirements for the
production process. Natural gas is assumed to produce the steam.
__Ejierjiy_Carrier_ _
Electricity183 0.065 MJ (0.018 kWh)
Stearn^ £J kg|0.21b|
Transportation. The corn products are transported approximately 16 km (10 mi) to the Four All
Seasons facility, and the soybean and blood meal products are transported approximately 97 km
(60 mi) to the facility.
Solid Waste. Any solid wastes from manufacturing are reused in the system, so no wastes need
to be modeled.
Transportation
A truck is assumed to transport the fertilizer to point of use, and the distance it travels is modeled
as a variable in the BEES system.
Installation
Any burdens that may arise from on-site application of fertilizer are not accounted for in BEES.
Use
The nitrogen in the fertilizer is assumed to be released over a 1.5 year period. Four All Seasons
fertilizer is fully biodegradable.
End of Life
There are no end of life burdens for this product since it is fully consumed during use,
eliminating the need for waste management.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
182 Sheehan, J. et al, NREL/SR-580-24089 (Washington, DC: US Department of Agriculture and US
Department of Energy, May 1998).
183 U.S. Energy Information Administration, Iowa's 2002 average price of electricity. Found at:
http://www.eia.doe.gov/cneaf/electricity. The 2002 price corresponds to the date for which the manufacturer
supplied data.
184 U.S. Energy Information Administration, Iowa's 2004 average price of industrial natural gas. Found at:
http://tonto.eia.doe.gov/dnav/ng/ng_pri_sum_a_EPGO_PIN_DMcf_a.htm. The 2004 price corresponds to the date
for which the manufacturer supplied data.
234
-------
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Graboski, Michael S., Fossil Energy Use in the Manufacture of Corn Ethanol (National Corn
Growers Association, August 2002).
Shapouri, H., "The 2001 net energy Balance of Corn-Ethanol" (U.S. Department of
Agriculture, 2004).
U.S. Environmental Protection Agency, "Grain Elevators and Processes, " Volume I: Section
9.9.1, AP-42: Compilation of Air Pollutant Emission Factors, (Washington, DC: U.S.
Environmental Protection Agency, May 2003). Found at:
http ://www. epa. gov/ttn/chief/ap42/ch09/fmal/c9s0909-1 .pdf
Galitsky, C., Worrell, E., and Ruth, M., Energy efficiency improvement and cost saving
opportunities for the corn wet milling industry, LBNL-52307 (Ernest Orlando Lawrence
Berkeley National Laboratory, July 2003).
U.S. Environmental Protection Agency, "Corn Wet Milling, " Volume I: Section 9.9.7, AP-42:
Compilation of Air Pollutant Emission Factors, (Washington, DC: U.S. Environmental
Protection Agency, January 1995). Found at:
http://www.epa.gov/ttn/chief/ap42/ch09/fmal/c9s09-7.pdf
Sheehan, J. et al., Life Cycle Inventory of Biodiesel and Petroleum Diesel for Use in an Urban
Bus, NREL/SR-5 80-24089 (Washington, DC: U.S. Department of Agriculture and U.S.
Department of Energy, May 1998).
Industry Contacts
Delayne Johnson, Four All Seasons (2005)
3.18 Transformer Oil
3.18.1 Generic Mineral Transformer Oil
Mineral oil-based transformer oil can be made from either naphtha or paraffin. Since the
naphthenic-based mineral oil carries a larger market share, it is used as the mineral oil base for
the product in BEES.185 The detailed environmental performance data for this product may be
viewed by opening the file G4010B.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The figure below shows the elements of mineral oil-based transformer oil production.
1 2001 telephone conversation with United Power Services, an independent transformer oil testing laboratory.
235
-------
Mineral Oil-Based
Transformer Oil
Figure 3.56: Mineral Oil-Based Transformer Oil System Boundaries
Raw Materials
Mineral-oil based transformer oil is composed of the materials listed in the Table below. The
density of the oil is assumed to be 0.864 kg/L ,186
Table 3.131. Mineral-Oil Based Transformer Oil Constituents
Constituent
Mass
(kg/kg oil)
Naphtha
Pour-point depressives and other additives
98%
2%
The production of naphtha requires extraction of crude oil and crude oil refining; since naphtha
is just one of many oil refinery products, only a portion of the inputs and outputs to these
processes is allocated to naphtha production. Data for these inputs and outputs is based on the
SimaPro and U.S. LCI Databases, as detailed below.
Crude Oil Extraction. This production component includes process flows associated with the
extraction of crude oil from the ground. U.S. LCI Database data used to represent extraction
from onshore and offshore wells range from the late 1990s to early 2000s.
Crude Oil Refining into Naphtha. Crude oil refining involves raw material and energy use as
well as emissions. Crude oil refining is based on an average U.S. refinery. It is assumed that the
material required by the refinery includes crude oil and other petroleum-based feedstocks,
purchased energy inputs, and process catalysts.
.From http://www.shell-lubricants.com/Electrical/diala hfx.html and
http://www.camd.lsu.edU/msds/t/transformer oil.htm.
236
-------
Crude oil refineries draw much of their energy requirements from the crude oil stream in the
form of still gas and catalyst coke as shown in the Table below. Additional energy requirements
and process needs are fulfilled by the other inputs listed in the Table.187
Table 3.132. U.S. Average Refinery Energy Use
Energy Carrier Annual Quantity
(MJ)
Still Gas 1.52E+12
Catalyst Coke 5.14E+11
Natural Gas 7.66E+11
Coal 3.27E+09
Steam 3.8E+10
Electricity 1.43E+11
Propane (C3H8, kg) 6.21E+10
Diesel Oil (kg) 3.16E+09
Heavy Fuel Oil 6.13E+10
Coke 1.77E+10
Other 8.8E+09
The emissions and energy requirements associated with the production of these fuels are
accounted for. Emissions are based on U.S. Environmental Protection Agency AP-42 emission
factors.
Allocation. Crude oil refineries produce a number of different petroleum products from crude
oil. The method for allocating total refinery energy use and total refinery emissions to the
production of naphtha is complicated by the fact that the refinery product mix is variable, both
among refineries and even with time for a given integrated refinery. The following method is
used to allocate refinery flows to naphtha production:
1. Calculate the percentage of total refinery energy use by refinery process.
2. Calculate naphtha's share of each process's energy consumption.
3. For each refinery process, multiply the corresponding results from steps 1 and 2 to get the
percentage of total refinery energy use allocated to naphtha refining
Manufacturing
Energy Requirements
After producing naphtha, pour-point depressives and other additives such as antioxidants are
added to give the transformer oil the properties it needs. The specifics for these additives can not
be reported because they are confidential, but their production data come from the SimaPro
database. The assumed energy requirement for producing the transformer oil is given in the
187 Energy Information Administration, Petroleum Supply Annual 1994, Report No. DOE/EIA-0340(94)/1, May
1995.
237
-------
Table below.188
Table 3.133. Energy Requirement for Mineral-Oil Based Transformer Oil Production
Quantity (per kg
Requirement oil)
Production Energy 1.6 MJ (0.44 kWh)
Transportation
Trucking is the mode of transport representing transportation from the transformer oil production
plant to the transformer to be filled at the point of use. The transportation distance is modeled as
a variable of the BEES system. Only trucking is modeled, and not pipeline transportation, since
transformer oil is a specialty petroleum product with a tiny market as compared to other
petroleum products. As a result, pipeline transportation burdens allocated to transformer oil are
assumed to be insignificant.
Use
The amount of oil used in a transformer depends on the size of the transformer. A relatively
small-sized (1 000 kV'A) transformer is assumed, which requires about 1.89 m3 (500 gal) of
fluid to cool. It is assumed that the use phase of the transformer oil lasts the lifetime of the
transformer, approximately 30 years. Included in the modeling is the electricity required to
recondition the oil when dissolved gas analysis tests indicate the need. Reconditioning is
assumed to occur every five years.189
End of Life
With periodic reconditioning of transformer oil during the 30-year life of the transformer, the oil
can be further reconditioned and reused in another transformer at end of life. This is assumed to
be the case; none of the product is landfilled.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
3.18.2 Generic Silicone Transfer Oil
Silicone-based transformer fluid is a synthetic transformer oil composed primarily of
dimethylsiloxane polymers, and follows a very different series of production steps than does
mineral oil-based transformer oil. The detailed environmental performance data for this product
may be viewed by opening the file G4010C.DBF under the File/Open menu item in the BEES
188 This data is based on confidential energy requirement data gathered for biobased transformer oil production
(summer 2005). It is used in the absence of more representative manufacturing energy information for this product.
189 Information on dissolved gas analysis testing can be found in the U.S. Bureau of Reclamation (USER)
website's Facilities Instructions Standards and Techniques (FIST) document,
http://www.usbr.gov/power/data/fist_pub.html. Energy information on reconditioning was provided during
telephone conversations with S.D. Myers, a transformer and transformer fluid contractor, November 2001.
238
-------
software.
Flow Diagram
The figure below shows the elements of silicone transformer fluid production.
Truck
Transport
Silicone-Bas
Transformer 1
Functional Unit
of Silicons-
Based Fluid
^ ,
Silicone
Transformer
Fluid Prod.
^ ,
Dimethyl-
siloxane
Production
^ ,
Energy
Production
ed
luid
Figure 3.57. Silicone-Based Transformer Oil System Boundaries
Raw Materials
While silicone-based fluid is produced both in the United States and abroad, the only publicly-
available data is European. European data is used to model the main component of the product,
cyclical siloxane.190
Manufacturing
The production of dimethylsiloxane starts with the production of dimethylchlorosilane using
chloromethane and silicon. Dimethylchlorosilane undergoes hydrolysis reactions to produce
dimethylsilanediol, which undergoes another series of hydrolysis reactions to condense into
cyclical siloxane. The average density of the fluid is assumed to be 0.9565 kg/L.191
Silicon production: JL Vignes, Donnees Industrielles, economiques, geographiques sur des produits
chimiques (mineraux et organiques) Metaux et Materiaux, pp. 134, ed. 1994, Union des Physiciens;
Dimethylchlorosilane production: "Silicones", Rhone-Poulenc departement silicones, Techno-Nathan edition,
Nouvelle Librairie, 1988; Dimethylsilanediol and cyclic siloxane production: Carette, Pouchol (RP Silicones),
Techniques de 1'ingenieur, vol. A 3475, p.3.
191 From http://www.clearcoproducts.com/pdf/msds/specialtv/MSDS-STO-50-Transformer-Oil.pdf and
http://www.dowcorning.com/applications/product finder/pf details.asp?ll=008&pg=00000642&prod=01496204&t
ype=PROD.
239
-------
Transportation
Trucking is the mode of transport used to represent transportation from the transformer oil
production plant to the transformer to be filled at point of use. The transportation distance is
modeled as a variable of the BEES system.
Use
The amount of oil used in a transformer depends on the size of the transformer. A relatively
small-sized (1 000 kV'A) transformer is assumed, which requires about 1.89 m3 (500 gal) of
fluid to cool. It is assumed that the use phase of the transformer oil lasts the lifetime of the
transformer, approximately 30 years. Included in the modeling is the electricity required to
recondition the oil when dissolved gas analysis tests indicate the need. Reconditioning is
assumed to occur every five years.192
End of Life
With periodic reconditioning of silicone-based transformer oil during the 30-year life of the
transformer, the oil is in good enough condition for half of it to be further reconditioned and
reused in another transformer. The other half is sent back to the manufacturer for restructuring
for production into other silicone-based products.193 End-of-life options for transformer oil do not
include waste disposal, as it is generally a well-maintained product and can be used in other
applications. Therefore, none of the product is assumed to be landfilled.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
3.18.3 Cooper Envirotemp FR3
Envirotemp FR3 Dielectric Coolant is a soy oil-based transformer fluid. A relatively small-sized
(1 000 kV'A) transformer is assumed for BEES, which requires about 1.89 m3 (500 gal) of fluid
to cool. The functional unit for Envirotemp FR3, as for all BEES transformer oils, is the use of
1.89 m3 (500 gal) of transformer fluid to cool a 1 000 kV-A transformer for a period of 30 years.
The detailed environmental performance data for this product may be viewed by opening the file
G4010D.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
192 Information on dissolved gas analysis testing can be found in the U.S. Bureau of Reclamation (USER)
website's Facilities Instructions Standards and Techniques (FIST) document,
http://www.usbr.gov/power/data/fist_pub.html. Energy information on reconditioning was provided during
telephone conversations with S.D. Myers, a transformer and transformer fluid contractor, November 2001.
193 Information from Dow Corning, http://www.dowcorning.com, "Reuse, recycle, or disposal of transformer
fluid," 2001.
240
-------
Envirotemp FR3 Dielectric Coolant
t
Degummed
soy oil
production
^
Production of
Additives
Figure 3.58: Envirotemp FR3 Dielectric Coolant System Boundaries
Raw Materials
The main constituent of Envirotemp FR3 is degummed soybean oil, and it contains small
amounts of other additives, shown in the Table below.
Table 3.134: Envirotemp FR3 Constituents
Constituent
Mass Fraction (%)
Degummed soybean oil
Additives
95
5
Data for soybean production comes from the U.S. LCI Database. Production data for soybean oil
comes from the National Renewable Energy Laboratory LCA study on biodiesel use in an urban
bus,194 in which degummed soy oil is modeled as the precursor to soy-based biodiesel. Additives
used in Envirotemp FR3 include a blend of natural esters and methacrylate resins, phenol
compounds, and coloring. These additives are not specified due to confidentiality concerns, but
they are included in the model and life cycle data for their production comes from the general
contents of the SimaPro LCA database.
194 Sheehan, J. et al, NREL/SR-580-24089 (Washington, DC: US Department of Agriculture and US
Department of Energy, May 1998).
241
-------
Manufacturing
Energy Requirements and Emissions. Steam from natural gas and electricity are used to heat
and blend a 22.71 m3 (6 000 gal) batch of Envirotemp FR3. The Table below presents the
quantities of each type of energy per gal of product (1 gal weighs 3.2 kg).
Table_3.135:
__Energ£_Carrier_ _
Electricity 0.216 MJ (0.06 kWh)
Naturaj_£_as [[[
Electricity and natural gas are modeled using the U.S. average electric grid from the U.S. LCI
Database.
Transportation. Soybean oil is assumed to be transported 322 km (200 mi) to the production
site. Transportation of additives is assumed to cover 800 km (500 mi) by truck to the
Envirotemp facility. Transportation data is based on the U.S. LCI Database.
Transportation
Heavy-duty truck transportation is used to represent transportation from the Envirotemp facility
to the transformer to be filled at the point of use. The distance traveled is modeled as a variable
of the BEES system.
Use
For BEES, Envirotemp FR3 Dielectric Fluid is used in a transformer with a capacity of 1.89 m3
(500 gal). Any type of transformer oil needs to be reconditioned or reclaimed over the life of the
transformer: transformer aging, thermal problems, or electrical problems can generate dissolved
gas, which results in deterioration or contamination of the fluid. Included in the BEES use phase
modeling is the electricity required to recondition the oil when dissolved gas analysis tests
indicate the need. Reconditioning is assumed to occur every five years.195 The transformer itself
is assumed to have a lifetime of 30 years.
End of Life
At the end of the 30-year life of the transformer, Envirotemp FR3 is modeled the same as most
all other transformer oils in BEES: at year 30, Envirotemp is assumed to be further reconditioned
and reused in another transformer. Included in the end-of-life modeling is the electricity
required to recondition the oil.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel . gov/lci/database.
195 Information on dissolved gas analysis testing can be found in the U.S. Bureau of Reclamation (USER)
website's Facilities Instructions Standards and Techniques (FIST) document,
http://www.usbr.gov/power/data/fist/fist3 -30. Energy information on reconditioning was provided during telephone
-------
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Sheehan, J. et al., Life Cycle Inventory ofBiodiesel and Petroleum Diesel for Use in an Urban
Bus, NREL/SR-5 80-24089 (Washington, DC: U.S. Department of Agriculture and U.S.
Department of Energy, May 1998).
Industry Contacts
Patrick McShane, Cooper Power Systems (February 2005)
3.18.4 ABB BIOTEMP
BIOTEMP, produced by ABB, Inc., is an insulating dielectric fluid used in transformers.
BIOTEMP is made from various raw vegetable oils, depending on the most ideal market
conditions at the time. The most common oils used in this product include sunflower, safflower,
and soybean. BIOTEMP is modeled for BEES assuming use of sunflower oil.
A relatively small-sized (1 000 kV'A) transformer is assumed for BEES, which requires about
1.89 m3 (500 gal) of fluid to cool. The functional unit for BIOTEMP, as for all BEES
transformer oils, is the use of 1.89 m3 (500 gal) of transformer fluid to cool a 1 000 kV-A
transformer for a period of 30 years.
The detailed environmental performance data for this product may be viewed by opening the file
G4010E.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
243
-------
BIOTEMP Transformer Oil
Functional Unit of
BIOTEMP
Antioxidant Additives
Production
Figure 3.59: BIOTEMP Transformer Oil System Boundaries
Raw Materials
BIOTEMP consists of a high oleic vegetable oil, for BEES a sunflower-based oil, and a small
quantity of antioxidant additives, in the proportions shown below.
Table 3.136: BIOTEMP Transformer Oil Constituents
Constituent Mass Fraction (%)
High oleic sunflower oil
Antioxidant additives
98.4
1.6
244
-------
Data on high oleic sunflower oil covers both sunflower production and production of the oil from
sunflower seeds. Sunflower production is modeled as a U.S. average using data aggregated from
various sources.196
Production of oil from sunflower seeds is modeled based on soybean crushing and crude oil
production data, adjusted using mass balance information pertaining to sunflowers.197
The specific antioxidants are phenol- and amine- based, and are not further specified to protect
manufacturer confidentiality. These are modeled, though, and the life cycle data for the
production of phenol and amine as base materials in the additives comes from the general
contents of the SimaPro LCA database.
Manufacturing
Energy Requirements and Emissions. At manufacturing, energy is used to heat and filter the
raw vegetable oil, blend in the antioxidants, and run the blended compound through a vacuum
process. The electricity required for these processes amounts to 1.8 MJ (0.5 kWh) per kilogram
of product. Electricity is modeled using the U.S. average electric grid from the U.S. LCI
Database.
Transportation. Truck transportation to the BIOTEMP facility for sunflower oil is assumed to
cover 5 230 km (3 250 mi), and for the additives is assumed to cover 1 127 km (700 mi).
Waste. Manufacturing waste includes spent filter cartridges. Approximately 0.003 kg (0.007 Ib)
of spent cartridges result from 1 kg of BIOTEMP production; this is sent to a landfill.
Transportation
Heavy-duty trucking is used to represent transportation from the BIOTEMP production facility
to the transformer to be filled at the point of use. The transportation distance is modeled as a
variable of the BEES system.
Use
For BEES, BIOTEMP transformer oil is used in a transformer with a capacity of 1.89 m3 (500
gal). Any type of transformer oil needs to be reconditioned or reclaimed over the life of the
transformer: transformer aging, thermal problems, or electrical problems can generate dissolved
gas, which results in deterioration or contamination of the fluid. Included in the BEES use phase
modeling is the electricity required to recondition the oil when dissolved gas analysis tests
indicate the need. Reconditioning is assumed to occur every five years.198 The transformer itself
196 Schmierer, J. et al, SF-SV-04 (Sacramento Valley: University of California Cooperative Extension, 2004).
Found at: http://www.agecon.ucdavis.edu/uploads/cost return articles/sunflowersv2004.pdf: National Sunflower
Association, 2005. Found at: http://www.sunflowernsa.com/growers/default.asp?contentID=72: Thomas Jefferson
Agricultural Institute, Columbia, MO, 2005. Found at:
http://www.jeffersoninstitute.org/pubs/sunflower.shtml#Fertilitv: U.S. Geological Survey, "National Totals By Crop
and Compound: Sunflower," . Found at: http://ca.water.usgs.gov/pnsp/crop/sunflower.html: Ontario Ministry of
Agriculture, Food, and Rural Affairs, "Herbicide recommendations for sunflower," (November 2002). Found at:
http://www.omafra.gov.on.ca/english/crops/pub75/12sunflo.htm.
197 Sheehan, J. et al, NREL/SR-580-24089 (Washington, DC: US Department of Agriculture and US
Department of Energy, May 1998).
198 Information on dissolved gas analysis testing can be found in the U.S. Bureau of Reclamation (USER)
245
-------
is assumed to have a lifetime of 30 years.
End of Life
At the end of the 30-year life of the transformer, BIOTEMP is modeled the same as most other
transformer oils in BEES: at year 30, BIOTEMP is assumed to be further reconditioned and
reused in another transformer, with reconditioning electricity included in the end-of-life
modeling. BIOTEMP is 97 % to 99 % biodegradable.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Schmierer, J. et al., Sample Costs to Produce Sunflowers for Seed in the Sacramento Valley,
SF-SV-04 (Sacramento Valley: University of California Cooperative Extension, 2004).
Found at: http://www.agecon.ucdavis.edu/uploads/cost_return_articles/sunflowersv2004.pdf
National Sunflower Association, 2005. Found at:
http://www.sunf! owernsa.com/growers/default. asp? contentID=72.
Thomas Jefferson Agricultural Institute, Columbia, MO, 2005. Found at:
http://www.ieffersoninstitute.org/pubs/sunflower.shtmltfFertility.
U.S. Geological Survey, "National Totals By Crop and Compound: Sunflower," National
Water Quality Assessment Pesticide National Synthesis Project. Found at:
http://ca.water.usgs.gov/pnsp/crop/sunflower.html.
Ontario Ministry of Agriculture, Food, and Rural Affairs, "Herbicide recommendations for
sunflower," Other Field Crops: Sunflowers: Introduction (November 2002). Found at:
http://www.omafra.gov.on.ca/english/crops/pub75/12sunflo.htm.
Sheehan, J. et al., Life Cycle Inventory of Biodiesel and Petroleum Diesel for Use in an Urban
Bus, NREL/SR-5 80-24089 (Washington, DC: U.S. Department of Agriculture and U.S.
Department of Energy, May 1998).
Industry Contacts
Don Cherry, ABB, Inc. (March 2005)
3.18.5 Generic Biobased Transformer Oil
Biobased transformer oil is relatively new to the market. Results of independent tests on the
performance of biobased transformer oil are comparable to results for other transformer oils,
such as the mineral-based and silicone-based fluids in BEES.
Biobased transformer oil is produced from vegetable oil feedstock. The detailed environmental
performance data for this product may be viewed by opening the file G4010F.DBF under the
File/Open menu item in the BEES software.
website's Facilities Instructions Standards and Techniques (FIST) document,
http://www.usbr.gov/power/data/fist/fist3-30. Energy information on reconditioning was provided during telephone
conversations with S.D. Myers, a transformer and transformer fluid contractor, November 2001.
246
-------
Flow Diagram
The flow diagram in the figure below shows the elements of biobased transformer oil production,
as it is currently modeled in BEES.
Biobased Transformer Fluid
Truck
Transport
Functional unit of biobased
fluid
Production of
manufacturing
energy
End-of-Life
Biobased
Transformer
Fluid Prod.
Biobased oil and additives
production (including energy
and materials)
Figure 3.60: Generic Biobased Transformer Oil System Boundaries
Raw Materials
Generic biobased transformer oil is composed of the materials listed in the Table below.
Table 3.137. Generic Biobased Transformer Oil Constituents
Mass
Constituent (kg/kg oil)
Biobased oil (soybean and/or other vegetable
oils)
Antioxidants and other additives
96.5 %
3.5%
Production data for converting soybeans to oil199 is updated with more recent U.S. LCI Database
data on soybean growing and harvesting. While fertilizer and agrichemical use, and some energy
use for farming equipment, are similar in amount to the older data, electricity use is different
(slightly higher), as is natural gas use. There are also additional inputs represented by the new
data, including lime.
Manufacturing
After producing biobased oil, antioxidants and other additives are added as enhancements. These
199 Sheehan, J. et al, NREL/SR-580-24089 (Washington, DC: US Department of Agriculture and US
Department of Energy, May 1998).
247
-------
additives are confidential so could not be reported, but their production data come from the
SimaPro database. The energy requirement for producing transformer oil is listed in the Table
below.200
Table 3.138. Biobased Transformer Oil Manufacturing Energy
Requirement Quantity (per kg oil)
Production Energy 1.6 MJ (0.44 kWh)
Transportation
Trucking is the mode of transport used to represent shipment of the product from the transformer
oil production plant to the transformer to be filled at the point of use. The transportation distance
is modeled as a variable of the BEES system.
Use
For BEES, generic biobased transformer oil is used in a transformer with a capacity of 1.89 m3
(500 gal). Any type of transformer oil needs to be reconditioned or reclaimed over the life of the
transformer: transformer aging, thermal problems, or electrical problems can generate dissolved
gas, which results in deterioration or contamination of the fluid. Included in the BEES use phase
modeling is the electricity required to recondition the oil when dissolved gas analysis tests
indicate the need. Reconditioning is assumed to occur every five years.201 The transformer itself
is assumed to have a lifetime of 30 years.
End of Life
At the end of the 30-year life of the transformer, generic biobased transformer oil is modeled the
same as most other transformer oils in BEES: at year 30, the product is assumed to be further
reconditioned and reused in another transformer, with reconditioning electricity included in the
end-of-life modeling.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
200 This data is based on confidential energy requirement data gathered from a biobased transformer oil producer
(summer 2005).
201 Information on dissolved gas analysis testing can be found in the U.S. Bureau of Reclamation (USER)
website's Facilities Instructions Standards and Techniques (FIST) document,
http://www.usbr.gov/power/data/fist/fist3-30. Energy information on reconditioning was provided during telephone
conversations with S.D. Myers, a transformer and transformer fluid contractor, November 2001.
248
-------
3.19 Carpet Cleaners
3.19.1 Racine Industries HOST Dry Carpet Cleaning System
Racine Industries' HOST Dry Carpet Cleaning System uses a Green Seal®-certified, biobased
cleaning compound. The HOST cleaning compound is a mixture of moisture, cleaning agents,
and recycled organic fibers that work as tiny sponges to absorb dirt from the carpet. The
compound is worked through the carpet with a brushing machine when working on large areas,
or with a hand brush or one's fingers when working on spots. The soiled compound is then
vacuumed, leaving a clean, dry carpet. The used product, being dry, does not require wastewater
treatment; it can be composted. HOST is used to clean commercial and residential carpets,
including those comprised of wool and other natural carpet fibers (it is also used to clean grout).
Use of this dry system reduces water use and avoids the energy and time associated with use of
dehumidifiers or air conditioners to dry carpets cleaned with wet systems. According to the
manufacturer, the HOST System also removes mold, dust mites, and allergens and is
manufactured in an EPA-registered facility (074202-WI-001).
For the BEES system, the function defined for carpet cleaning is cleaning 92.9 m2 (1 000 ft2) of
carpet, which amounts to use of 4.25 kg (9.37 Ib) of HOST.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
249
-------
Racine Industries - HOST Dry Carpet Cleaner
Trick Transport to
Use
Functional Unit
of Cleaner
Cleaning
Electricity
HOST Dry Carpet
Cleaner
Production
Pro cess Energy
Raw Material
Tra report
Processed
Recycled Fibers
Other Material
Production
Figure 3.61: HOST Dry Carpet Cleaning System Boundaries
Raw Materials
HOST is made up of the materials shown in the Table below.
Table 3.139: HOST Dry Carpet Cleaning System Constituents
Constituent Mass Fraction (%)
Water
Processed organic fiber
Other material inputs
63
31
6
Processed organic fiber. Processed organic fiber (POP) is comprised of 100 % pre-consumer
waste from industrial processing. Because this fiber would otherwise be a waste material, no
impacts from fiber production or fiber-based product production are accounted for. However,
transportation of the fiber to the Racine plant, as well as energy requirements for manufacturing
the fiber into usable material in HOST, are accounted for in BEES, as described below under
Manufacturing.
250
-------
Other material inputs
Emulsion Polymer. Production data for methyl methacrylate, used to represent the emulsion
polymer, comes from publicly available European data.202
Citrus extract. For production purposes, this extract from citrus rind is considered a coproduct
of orange production. It is assumed to comprise 0.5 % of the total mass of useful orange
products, which include orange juice, cattle peel feed, and alcohol. Orange production data
comes from a variety of sources.203'204'205
Other ingredients. Data for remaining ingredients comes from several sources, including a
United Nations publication on fertilizer production,206 elements of the U.S. LCI and SimaPro
databases, engineering calculations, and a European life-cycle inventory containing late 1990s
data on European detergent production.207 A solvent is modeled as naphtha, whose production
data comes from petroleum refining process data found in a National Renewable Energy
Laboratory LCA study on biodiesel use in an urban bus,208 in which petroleum-based diesel fuel
is compared to biodiesel.
Manufacturing
Energy Requirements and Emissions. A total of 0.022 MJ (0.06 kWh) electricity is used in
processing HOST, and covers the following processes:
• Blending the constituents
• Conveying and blending the liquid and POP
• Fill line packaging
• Lighting, controls, and ventilation associated with producing HOST
Electricity is modeled using the U.S. average grid, and data for electricity are from the U.S. LCI
Database. Natural gas is required to process the organic fiber and amounts to 1.2 MJ (0.33 kWh)
per kilogram of HOST. Data are from the U.S. LCI Database.
Processing Materials. A sanitizer is used to sanitize process equipment. Water is used to rinse
the blending tank and to clean and sanitize the POP processing and conveyance system and
filling line. Quantities of these ancillary materials are reported in the Table below.
202 Boustead, I., "Report 14: Polymethyl Methacrylate," (Association of Plastics Manufacturers of Europe,
September 1997), pp. 27-29. Found at: http://www.apme.org.
203 National Agricultural Statistics Service, 2005. Found at:
http://www.nass.usda.gov:8080/QuickStats/index2.jsp.
204 Reposa, J. Jr. and Pandit, A., "Inorganic Nitrogen, Phosphorus, and Sediment Losses from a Citrus Grove
during Stormwater Runoff (Melbourne, FL: Civil Engineering Program, Florida Institute of Technology). Found
at: http://www.stormwaterauthority.org/assets/023PLreposacitrus.pdf.
205 Extrapolation of data on agricultural production in the U.S. LCI Database.
206 International Fertilizer Industry Association, "Part 1: the Fertilizer Industry's Manufacturing Processes and
Environmental Issues," ISBN: 92-807-1640-9 (Paris: United Nations Environment Programme, 1998).
207 Dall'Acqua, S., et al., Report #244 (St. Gallen: EMPA, 1999).
208 Sheehan, J. et al., NREL/SR-580-24089 (Washington, DC: US Department of Agriculture and US
Department of Energy, #244 (St. Gallen: EMPA, 1999).
251
-------
Material
Sanitizer 0.015 g (0.0005 oz)
Vater
Solid Waste. Some waste is generated during processing, and includes quality assurance
samples, filling line start-up waste, and plastic container waste, all of which amount to 0.003 kg
(0.008 Ib) per kg product. A portion of this waste is landfilled, while a portion is stored as
samples.
Transportation. The transportation distance for all the, constituents besides organic fiber and
sanitizer is approximately 80 km (50 mi). The fiber is transported about 563 km (350 mi) to the
facility, and sanitizer is supplied locally (within 8 km, or 5 mi). All materials are transported by
diesel truck, whose burdens are modeled based on data in the U.S. LCI Database.
Transportation
Product transport to the customer via diesel truck is a variable in BEES, and is modeled based on
the U.S. LCI Database.
Use
A total of 4.25 kg (9.37 Ib) of HOST are needed to clean 92.9 m2 (1 000 ft2) of carpet. HOST is
distributed on the floor, brushed, and then vacuumed away. Electricity use associated with
brushing the cleaner through the carpet and vacuuming is obtained by averaging the cleaning
time based on use of the following three types of vacuum cleaners, for an overall average of 12.5
min per 92.9 m2 (per 1 000 ft2):209
• Upright Vacuum (from 30 cm to 61 cm in width, or from 12 in to 24 in)
• Large Area Push-Type Vacuum (66 cm to 91 cm, or 26 in to 36 in)
• Backpack Vacuum & Orifice Carpet Tool (30 cm to 61 cm, or 12 in to 24 in)
Assuming a 1 500 W (2.012 hp) motor and taking into account the first stage of brushing and the
second stage of vacuuming, the electricity required to clean 92.9 m2 (1 000 ft2) is 135 MJ (37.6
kWh), or 32 MJ (8.8 kWh) per kilogram of HOST.210 Electricity is modeled based on the U.S.
average electric grid from the U.S. LCI Database.
End of Life
The contents of the vacuum filter bag or hopper are typically emptied into a waste bin for
landfilling. The mass of the cleaner is accounted for in the landfill modeling for this product.
While some residential and commercial consumers compost vacuum waste, this is not considered
in the BEES product model.
209 International Sanitary Supply Associations (ISSA), "Cleaning Applications and Tasks," The Official 358
Cleaning Times, 1999.
210 This assumes the brushing stage uses the same quantity of energy as the vacuuming stage.
252
-------
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Boustead, I., "Report 14: Polymethyl Methacrylate," Eco-profiles of the European Plastics
Industry (Association of Plastics Manufacturers of Europe, September 1997), pp. 27-29.
Found at: http://www.apme.org.
National Agricultural Statistics Service, 2005. Found at:
http://www.nass.usda.gov:8080/OuickStats/index2.jsp.
Reposa, J. Jr. and Pandit, A., "Inorganic nitrogen, phosphorus, and sediment losses from a
citrus grove during stormwater runoff (Melbourne, FL: Civil Engineering Program, Florida
Institute of Technology, date unknown). Found at:
http://www.stormwaterauthoritv.org/assets/023PLreposacitrus.pdf
International Fertilizer Industry Association, "Part 1: the Fertilizer Industry's Manufacturing
Processes and Environmental Issues," Mineral Fertilizer Production and the Environment,
ISBN: 92-807-1640-9 (Paris: United Nations Environment Programme, 1998).
Dall'Acqua, S., et al., Life Cycle Inventories for the Production of Detergent Ingredients,
Report #244 (St. Gallen: EMPA, 1999).
Sheehan, J. et al., Life Cycle Inventory of Biodiesel and Petroleum Diesel for Use in an Urban
Bus, NREL/SR-5 80-24089 (Washington, DC: U.S. Department of Agriculture and U.S.
Department of Energy, May 1998).
Industry Contacts
Deborah Lema (2006)
3.20 Floor Stripper
3.20.1 Nano Green Floor Stripper
Nano Green mastic remover and floor stripper are two applications in the Nano Green Sciences,
Inc. line of janitorial and sanitation products. Nano Green is biobased and biodegradable. It is
extracted and blended from U.S. Food and Drug Administration (FDA)-approved food stocks,
principally corn, grains, soybeans, and potatoes, and, according the manufacturer, its cleaning
capabilities have been shown to be as effective as those of almost any detergent, cleaner, or soap
in the marketplace today.
Nano Green falls into two BEES product categories: mastic remover and floor stripper. For the
BEES system, the function of mastic remover is removing 9.29 m2 (100 ft2) of mastic under
vinyl or similar flooring over a period of 50 years. The function of floor stripper in BEES is
removing three layers of wax and one layer of sealant from 9.29 m2 (100 ft2) of hardwood
flooring.
The detailed environmental performance data for these products may be viewed by opening the
file H1012A.DBF, for the floor stripper, and the file J1010B.DBF, for the mastic remover, under
the File/Open menu item in the BEES software.
253
-------
Flow Diagram
The flow diagram below shows the major elements of the production of Nano Green as it is
currently modeled for BEES.
Nano Green Mastic Remover and Floor Stripper
1
Potato based
chelating
agent
T
Potato
Production
t
Truck
Transport to
User
1
Functional Unit of
Nano Green
1 •
Nano Green
Production
J L
Corn-based
amino acids
Corn-based
nonionic
surfactants
T
Corn
production
T
Corn
production
— ^ End-of-life
Process
Energ
Raw mat
transpo
Tall oil fatty
acid
Wood
production
1
1
Fertilizer
production
Agrichemicals
production
•
i
srial
rt
3 rain-based
organic
alcohol
Corn
production
t
Figure 3.62: Nano Green System Boundaries
Raw Materials
The materials contained in Nano Green are listed in the Table below. Each is found on the FDA-
approved Everything Added to Food in the United States (EAFUS) list.
Table 3.141: Nano Green Product Constituents
Constituent
Mass Fraction (%)
Corn-based amino acids
Corn-based nonionic surfactants
Tetracetic acid (potato based chelating
agent)
Grain-based organic alcohol
Tall oil fatty acid
16
32
16
16
2
Corn-based amino acids. No data are available for the production of corn-based amino acids
per se; corn starch is used as a surrogate since amino acids are often produced via fermentation,
with corn starch as the raw material. Corn starch is assumed to be produced by the wet milling
254
-------
process, with ethanol and other coproducts allocated away. Data on wet milling comes from a
study by Lawrence Berkeley National Laboratory.211 Data on particulate matter emissions comes
from the U.S. Environmental Protection Agency AP-42 emissions factors.212 Corn growing and
production data comes from the U.S. LCI Database.
Corn-based nonionic surfactant. Nano Green uses a corn-based nonionic surfactant; in the
absence of available data on its production, anionic surfactants are used as a surrogate.
Specifically, production data for palm kernel oil (PKO) and coconut oil (CNO) based alkyl
polyglocosides (APG) from a European life cycle study of detergent surfactants production are
averaged.213 Since corn content is substantial, comprising 33% and 36% of the material
requirements for APG-CNO and APG-PKO, respectively, these surfactants are judged to be
viable surrogates.
Potato-based chelating agent. Potato starch is used as a surrogate for the tetracetic acid
constituent, with data for its production coming from the Danish LCA food database.214 Data for
potato production comes from the U.S. LCI Database.
Grain-based organic alcohol. Corn ethanol is assumed to be the basis for the grain-based
organic alcohol constituent. Ethanol production is modeled using an average of dry and wet
milling operations.215
Tall oil fatty acid. Data for tall oil fatty acid is based mainly on data for tall oil alkyd, found in a
Finnish LCA study on coated exterior wood cladding.216 The tall oil fatty acid is modeled as
comprising 95 % of the mass of inputs and outputs as it is a precursor to the alkyd.
Manufacturing
Energy Requirements and Emissions. Energy is used in Nano Green production primarily to
blend the product using a 0.5 hp motor. Blending 3.785 m3 (1 000 gal) for approximately four h
amounts to 0.002 hp-h/gal. Electricity is modeled using the U.S. average electric grid from the
U.S. LCI Database.
Transportation. All materials are transported by diesel truck approximately 805 km (500 mi) to
211 Galitsky, C., Worrell, E., and Ruth, M., LBNL-52307 (Ernest Orlando Lawrence Berkeley National
Laboratory, July 2003).
212 U.S. Environmental Protection Agency, "Corn Wet Milling," Volume I: Section 9.9.7, AP-42: Compilation
of Air Pollutant Emission Factors (Washington, DC: US Environmental Protection Agency, January 1995). Found
at: http://www.epa.gov/ttn/chief/ap42/ch09/final/c9s09-7.pdf.
213 Stalmans, H., et al., "European Life-Cycle Inventory for Detergent Surfactants Production," , Vol. 32, No. 2,
1995, pp. 84-109.
214 Danish LCA Food Database, found at: http://www.lcafood.dk/processes/industry/potatoflourproduction.htm.
215 Graboski, Michael S., (National Corn Growers Association, August 2002); Shapouri, H., "The 2001 Net
Energy Balance of Corn-Ethanol" (U.S. Department of Agriculture, 2004); U.S. Environmental Protection Agency,
"Grain Elevators and Processes," Volume I: Section 9.9.1,AP-42: Compilation of Air Pollutant Emission Factors
(Washington, DC: US Environmental Protection Agency, May 2003). Found at:
http://www.epa.gov/ttn/chief/ap42/ch09/final/c9s0909-l.pdf. Wet milling data sources are cited under Corn-based
Amino Acids.
216 yp,p Technical Research Centre of Finland, "Environmental Impact of Coated Exterior Wooden Cladding,"
1999.
255
-------
the manufacturing facility. Diesel trucking is modeled based on the U.S. LCI Database.
Transportation
Diesel trucking is used to transport the product from the Nano Green facility to the building site,
and is modeled based on the U.S. LCI Database. The trucking distance is a variable in BEES.
Use
When Nano Green is used as a mastic remover, approximately 0.002 m3 (0.5 gal) is needed to
remove 18.6 m2 (200 ft2) of mastic from the floor. It is assumed that Nano Green is applied twice
to remove mastic over a period of 50 years. The same amount of Nano Green is required to
remove several layers of wax and sealant from 9.29 m2 (100 ft2) of hardwood flooring, but it is
assumed that the floor is completely stripped only once over the 50 year BEES use period. Other
data on use are not available.
End of Life
The mass of Nano Green at end of life is accounted for in the landfill modeling for this product.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Galitsky, C., Worrell, E., and Ruth, M., Energy Efficiency Improvement and Cost Saving
Opportunities for the Corn Wet Milling Industry, LBNL-52307 (Ernest Orlando Lawrence
Berkeley National Laboratory, July 2003).
U.S. Environmental Protection Agency, "Corn Wet Milling, " Volume I: Section 9.9.7, AP-42:
Compilation of Air Pollutant Emission Factors., (Washington, DC: U.S. Environmental
Protection Agency, January 1995). Found at:
http://www.epa.gov/ttn/chief/ap42/ch09/final/c9s09-7.pdf
Stalmans, H., et al., "European Life-Cycle Inventory for Detergent Surfactants Production,"
Tenside, Surfactants, Detergents, Vol. 32, No. 2, 1995, pp. 84-109.
Danish LCA Food Database, found at:
http://www.lcafood.dk/processes/industrv/potatoflourproduction.htm.
Graboski, Michael S., Fossil Energy Use in the Manufacture of Corn Ethanol (National Corn
Growers Association, August 2002).
Shapouri, H., "The 2001 net energy Balance of Corn-Ethanol" (U.S. Department of
Agriculture, 2004).
U.S. Environmental Protection Agency, "Grain Elevators and Processes, " Volume I: Section
9.9.1, AP-42: Compilation of Air Pollutant Emission Factors, (Washington, DC: U.S.
Environmental Protection Agency, May 2003). Found at:
http ://www. epa. gov/ttn/chief/ap42/ch09/fmal/c9s0909-1 .pdf.
VTT Technical Research Centre of Finland, "Environmental Impact of Coated Exterior
Wooden Cladding," 1999.
Industry Contacts
Alvin Bojar, Nano Green Sciences, Inc. (2005)
256
-------
3.21 Glass Cleaner
3.21.1 Spartan Green Solutions Glass Cleaner
Spartan Chemical Company, Inc. Green Solutions Glass Cleaner is formulated to penetrate,
emulsify, and remove dirt with minimal effort. Green Solutions contains no fragrances, dyes, or
VOC. It is Green Seal-certified and it meets Green Seal's environmental standard for industrial
and institutional cleaners based on its reduced human and aquatic toxicity and reduced smog
production potential.
For the BEES system, 3.785 m3 (1 000 gal) of ready-to-use glass cleaner is studied.217 Green
Solutions is produced in concentrated form and diluted at the point of use. For 3.785 m3 (1 000
gal) of ready-to-use Green Solutions, 56 kg (120 Ib) of concentrate is used. The detailed
environmental performance data for this product may be viewed by opening the file
H1013B.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
217 While it is unrealistic to assume a need for such a large quantity at a given time, this amount is used so that
the environmental impacts for the product are large enough to be reported in the BEES results.
257
-------
Spartan Green Solutions Glass Cleaner
Truck
Transport to
Use
— *
Functional Unit of
Glass Cleaner
Dilution
water
Fertilizer
production
Agrichemicals
production
Figure 3.63: Green Solutions Glass Cleaner System Boundaries
Raw Materials
Green Solutions glass cleaner is comprised of the following materials.
Table 3.142: Green Solutions Glass Cleaner Constituents
Constituent
Mass Fraction (%)
Water
Polyethylene glycol
Alkyl polyglycoside
surfactant
Ethoxylated alcohol
Sodium carbonate
Citric acid
94
1-5
1-5
1-5
1-5
1-5
A portion of the alkyl polyglycoside surfactant is corn-based and assumed to be corn ethanol, for
which production data is based on an average of wet- and dry-milling processes. Data for
1 Some mass fractions are presented as ranges to protect confidential information.
258
-------
production of corn comes from the U.S. LCI Database. Process inputs and outputs for ethanol
from dry milling come from two ethanol studies.219'220 Wet milling data comes from a corn wet
milling study addressing energy efficiency.221 The U.S. Environmental Protection Agency AP-
42 emissions factors provide air emissions data on wet and dry milling.222'223
Polyethylene glycol is assumed to be a copolymer of ethylene oxide and propylene oxide. Data
for these substances comes from a source with late 1990s European production data224 and from
elements of the SimaPro and U.S. LCI Databases. An LCA study on detergents225 provides the
data for alcohol ethoxylate, which is used to produce the ethoxylated alcohol in the product.
The production of sodium carbonate is based on the U.S. LCI Database module for soda ash.
Citric acid is not included in the model in the absence of available data. Overall, however, the
small quantity of citric acid use is judged to contribute little to the raw materials burdens for the
product.
Manufacturing
Energy Requirements and Emissions. Product manufacturing consists of a simple chemical
blending operation requiring virtually no heat or pressure. Items in the formulation are drum or
bulk storage materials that are added to the open top mixing vessel via an air-operated drum lift
or air actuated valve. The batching water is used at ambient temperature so no heating is
required. The quantity of electricity required to blend one gal is 0.0025 MJ (0.0007 kWh).
Electricity is modeled using the U.S. average electric grid from the U.S. LCI Database.
Transportation. Materials are transported varying distances ranging from 14 km (9 mi) to 885
km (550 mi) to the plant. Materials are transported by diesel truck, which is modeled based on
the U.S. LCI Database.
Transportation
All final product shipping occurs via diesel semi-truck to approximately 450 points of
distribution around the country, averaging a distance of 1 207 km (750 mi) to the customer. This
default transportation distance may be adjusted by the BEES user. Diesel trucking is modeled
based on the U.S. LCI Database.
Use
According to user directions, two ounces of concentrated cleaner are used per gal of water, a
219 Graboski, Michael S., (National Corn Growers Association, August 2002).
220 Shapouri, H., "The 2001 Net Energy Balance of Corn-Ethanol" (U.S. Department of Agriculture, 2004).
221 Galitsky, C., Worrell, E., and Ruth, M, LBNL-52307 (Ernest Orlando Lawrence Berkeley National
Laboratory, July 2003).
222 U.S. Environmental Protection Agency, "Grain Elevators and Processes," Volume I: Section 9.9.1
(Washington, DC: US Environmental Protection Agency, May 2003). Found at:
http://www.epa.gov/ttn/chief/ap42/ch09/final/c9s0909-l.pdf.
223 U.S. Environmental Protection Agency, "Corn Wet Milling," Volume I: Section 9.9.7 (Washington, DC: US
Environmental Protection Agency, January 1995). Found at: http://www.epa.gov/ttn/chief/ap42/ch09/final/c9s09-
7.pdf.
224 European Commission, "Reference Document on Best Available Techniques in the Large Volume Organic
Chemical Industry" , February 2002.
225 Dall'Acqua, S., et al., Report #244 (St. Gallen: BMP A, 1999).
259
-------
dilution ratio of 1:64. The density of Green Solutions glass cleaner is 3.8 kg (8.4 Ib) per gal. As
a result, 0.067 m3 (17.6 gal) of water are used per kilogram of concentrate. For 3.785 m3 (1 000
gallons) of ready to use glass cleaner, 56 kg (120 Ib) of the concentrate are used. Other data on
use, such as application rates and frequencies, are neither available nor uniform among users.
End of Life
No end-of-life modeling is required, since the product is fully consumed during use.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Galitsky, C., Worrell, E., and Ruth, M., Energy efficiency improvement and cost saving
opportunities for the corn wet milling industry, LBNL-52307 (Ernest Orlando Lawrence
Berkeley National Laboratory, July 2003).
Graboski, Michael S., Fossil Energy Use in the Manufacture of Corn Ethanol (National Corn
Growers Association, August 2002).
Shapouri, H., "The 2001 net energy Balance of Corn-Ethanol" (U.S. Department of
Agriculture, 2004).
U.S. Environmental Protection Agency, "Corn Wet Milling, " Volume I: Section 9.9.7, AP-42:
Compilation of Air Pollutant Emission Factors, (Washington, DC: U.S. Environmental
Protection Agency, January 1995). Found at:
http://www.epa.gov/ttn/chief/ap42/ch09/fmal/c9s09-7.pdf
U.S. Environmental Protection Agency, "Grain Elevators and Processes, " Volume I: Section
9.9.1, AP-42: Compilation of Air Pollutant Emission Factors, (Washington, DC: U.S.
Environmental Protection Agency, May 2003). Found at:
http ://www. epa. gov/ttn/chief/ap42/ch09/fmal/c9s0909-1 .pdf
European Commission, "Reference Document on Best Available Techniques in the Large
Volume Organic Chemical Industry", Integrated Pollution Prevention and Control (IPPC),
February 2002.
Dall'Acqua, S., et al., Life Cycle Inventories for the Production of Detergent Ingredients,
Report #244 (St. Gallen: EMPA, 1999).
Industry Contacts
Bill Schalitz (2005)
260
-------
3.22 Bath and Tile Cleaner
3.22.1 Spartan Green Solutions Restroom Cleaner
Spartan Chemical Company, Inc. Green Solutions Restroom Cleaner is a natural acid toilet,
urinal, and shower room cleaner. It contains 8 % natural citric acid, a hard water scale remover
that cleans soap scum, water spots, and light rust from toilet bowls, urinals, and shower room
walls and floors. Green Solutions Restroom Cleaner is Green Seal-certified and it meets Green
Seal's environmental standard for industrial and institutional cleaners.
For the BEES system, 3.8 L (1 gal) of ready-to-use cleaner is studied. The detailed
environmental performance data for this product may be viewed by opening the file
H1014A.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
Spartan Green Solutions Restroom Cleaner
Corn
production
t
Sugar cane
production
j
Fertilizer
production
Agrichemicals
production
Fertilizer
production
Agrichemicals
production
Figure 3.64: Green Solutions Restroom Cleaner System Boundaries
Raw Materials
Green Solutions Restroom Cleaner is comprised of the following materials.
261
-------
Table 3.143: Green Solutions Res^oom^CJeaner Constituents
Constituent
Water 91
Citric acid 8
Ethoxylated alcohol 0.1 to 1
Oo
In general, citric acid may be manufactured from several renewable natural resources: citrus
fruits, pineapple waste, or crude sugars. The citric acid in this product is modeled as coming
from molasses from sugar cane. Citric acid process data comes from a plant in the United States
that produces approximately 10 million kg (22 million Ib) of crystalline citric acid per year.226
Both sugar cane production data and data representing molasses extraction from the sugar cane
come from the U.S. Department of Agriculture Economic Research Service.227'228
An LCA study on detergents229 provides the data for alcohol ethoxylate. Xanathan gum is a
thickening agent produced naturally by bacteria. For BEES, xanathan gum is assumed to be corn
sugar based, and as such, corn starch is used as the basis for the sweetener. Corn starch is
produced by the wet milling process for which data comes from a Lawrence Berkeley National
Laboratory study.230 Data on parti culate matter emissions from wet milling comes from the U.S.
Environmental Protection Agency AP-42 emissions factors.231 Corn growing and production
data comes from the U.S. LCI Database.
Manufacturing
Energy Requirements and Emissions. Product manufacturing consists of a simple chemical
blending operation with virtually no heat or pressure involved. Items in the formulation are
drum or bulk storage materials that are added to the open top mixing vessel via an air-operated
drum lift or air actuated valve. The batching water is used at ambient temperature so no heating
is required. The quantity of electricity required to blend one gal of the product is 0.0025 MJ
(0.0007 kWh). Electricity is modeled using the U.S. average electric grid from the U.S. LCI
Database.
Transportation. Materials are transported varying distances to the plant, ranging from 14 km (9
mi) for the ethoxylated alcohol to 805 km (500 mi) for the xanathan gum. Materials are
transported by diesel truck, which is modeled based on the U.S. LCI Database.
226
227
Petrides, Demetri(Intelligen, Inc.), 2001.
U.S. Department of Agriculture Economic Research Service, :
http://ers.usda.gov/Data/sdp/view.asp?f=specialty/89019/&arc=C: http://www.ers.usda.gov/briefing/sugar/data.htm.
228 Resource Economics Division of the Economic Research Service(Washington, DC: U.S. Department of
Agriculture, 1997).
229 Dall'Acqua, S., et al., Report #244 (St. Gallen: BMP A, 1999).
230 Galitsky, C., Worrell, E., and Ruth, M, LBNL-52307 (Ernest Orlando Lawrence Berkeley National
Laboratory, July 2003).
231 U.S. Environmental Protection Agency, "Corn Wet Milling," Volume I: Section 9.9.7(Washington, DC: US
Environmental Protection Agency, January 1995). Found at: http://www.epa.gov/ttn/chief/ap42/ch09/final/c9s09-
7.pdf.
262
-------
Transportation
All final product shipping occurs via diesel semi-truck to approximately 450 points of
distribution around the country, averaging a distance of 1 207 km (750 mi) to the customer. This
default transportation distance may be adjusted by the BEES user. Diesel trucking is modeled
based on the U.S. LCI Database.
Use
Green Solutions is VOC-free and can be used both "as is" and diluted. According to the
manufacturer's customer use data, most of the time it is not diluted; when it is, a 1:10 dilution
ratio is the average. For BEES, the product is assumed to be used in undiluted form. Other data
on use, such as application rates and frequencies, are neither available nor uniform among users.
End of Life
No end-of-life modeling is required since the product is fully consumed during use.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Petrides, Demetri, Bioprocess Design (Intelligen, Inc.), 2001.
U.S. Department of Agriculture Economic Research Service, Sugar and Sweetener Yearbook:
http://ers.usda.gov/Data/sdp/view.asp?f=specialty/89019/&arc=C:
http://www.ers.usda.gov/briefmg/sugar/data.htm.
Resource Economics Division of the Economic Research Service, Farm Business Economics
Report, 1996, Report # ECI-1997 (Washington, DC: U.S. Department of Agriculture, 1997).
Dall'Acqua, S., et al., Life Cycle Inventories for the Production of Detergent Ingredients,
Report #244 (St. Gallen: EMPA, 1999).
Galitsky, C., Worrell, E., and Ruth, M., Energy efficiency improvement and cost saving
opportunities for the corn wet milling industry, LBNL-52307 (Ernest Orlando Lawrence
Berkeley National Laboratory, July 2003).
U.S. Environmental Protection Agency, "Corn Wet Milling, " Volume I: Section 9.9.7, AP-42:
Compilation of Air Pollutant Emission Factors, (Washington, DC: U.S. Environmental
Protection Agency, January 1995). Found at:
http://www.epa.gov/ttn/chief/ap42/ch09/fmal/c9s09-7.pdf
Industry Contacts
Bill Schalitz, Spartan Chemical Company, Inc. (2005)
263
-------
3.23 Grease & Graffiti Remover
3.23.1 VertecBio Gold Graffiti Remover
VertecBio™ Gold is a corn and soybean derived solvent used to remove spray paint and ink
from all types of surfaces. It is a light gold liquid with low volatility that is rinsed away with
water.
For the BEES system, 3.8 L (1 gal) of VertecBio™ Gold is studied. The detailed environmental
performance data for this product may be viewed by opening the file H1015C.DBF under the
File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
VertecBio Gold Graffiti Remover
True
Transport to
Use
l~
Functional U
Graffiti Rerr
1 :
VertecBk
Gol
productio
t
Methyl soyate
production
T
Soybean
Production
t
Fertilizer
production
1
Agrichemicals
production
nit of
over
n F
1
Ethyl lactate
production
t
Cor
Production
T
Fertilizer Ag
production p
Proces
Energy
aw Material
transport
richemicals
reduction
Figure 3.65: VertecBio™ Gold System Boundaries
264
-------
Raw Materials
VertecBio™ Gold is primarily made up of the materials shown in the Table below.
Table 3.144: VertecBio™ Gold Graffiti Remover Constituents
Constituent Mass Fraction (%)
Ethyl lactate 50
Methyl soyate 50
Data for the soybean-based input, methyl soyate, is based on soybean production data from the
U.S. LCI Database. Data for both the production of soybean oil and the esterification process
used to produce methyl soyate comes from a National Renewable Energy Laboratory LCA study
on biodiesel use in an urban bus.232 Information on ethyl lactate comes from the manufacturer,233
elements of the U.S. LCI Database, a report by Lawrence Berkeley National Laboratory on corn
wet milling,234 and U,S. EPA AP-42 emissions factors.235
Manufacturing
Energy Requirements and Emissions. VertecBio™ Gold production involves mixing the
components in batches. No heating of the components is required. Energy is used for pumping
raw materials into a 3.78 m3 (1 000 gal) vessel, mixing the components, and pumping the
product out of the vessel. Actual energy requirements are not available; the pumps are assumed
to require 1.5 kW (2 hp) for a duration of 1 h and the mixer is assumed to require 15 kW (20 hp)
for a duration of 1 h, based on conversations with production facility personnel. Total energy
use per 3.785 m3 (1 000 gal) batch is calculated to be 59.1 MJ (16.4 kWh), or 0.06 MJ (0.02
kWh) per gal.
Transportation. The transportation distance for shipping the raw materials to the manufacturing
plant by diesel truck is assumed to be 402 km (250 mi). Diesel trucking burdens are modeled
based on the U.S. LCI Database.
Transportation
Product transport is assumed to cover 1 175 km (730 mi) by diesel truck, which is modeled
based on the U.S. LCI Database.
Use
One gal of VertecBio™ Gold weighs 3.56 kg (7.85 Ib), and it is fully biodegradable. No data on
effluents from rinsing the product are available.
End of Life
No end-of-life modeling is required since the product is fully consumed during the use phase.
232 Sheehan, J. et al, NREL/SR-580-24089 (Washington, DC: US Department of Agriculture and US
Department of Energy, May 1998).
233 Phone conversation with Rathin Datta, Vertec Biosolvents, September 20, 2004.
234 Galitsky, C., Worrell, E., and Ruth, M., LBNL-52307 (Ernest Orlando Lawrence Berkeley National
Laboratory, July 2003).
235 U.S. Environmental Protection Agency, "Corn Wet Milling," Volume I: Section 9.9.7, AP-42: Compilation
of Air Pollutant Emission Facfor-s^Washington, DC: US Environmental Protection Agency, January 1995). Found
at: http://www.epa.gov/ttn/chief/ap42/ch09/final/c9s09-7.pdf
265
-------
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Sheehan, J. et al., Life Cycle Inventory of Biodiesel and Petroleum Diesel for Use in an Urban
Bus, NREL/SR-5 80-24089 (Washington, DC: U.S. Department of Agriculture and U.S.
Department of Energy, May 1998).
Galitsky, C., Worrell, E., and Ruth, M., Energy efficiency improvement and cost saving
opportunities for the corn wet milling industry, LBNL-52307 (Ernest Orlando Lawrence
Berkeley National Laboratory, July 2003).
U.S. Environmental Protection Agency, "Corn Wet Milling, " Volume I: Section 9.9.7, AP-42:
Compilation of Air Pollutant Emission Factors, (Washington, DC: U.S. Environmental
Protection Agency, January 1995). Found at:
http://www.epa.gov/ttn/chief/ap42/ch09/fmal/c9s09-7.pdf
Industry Contacts
Vertec Biosolvents, Inc. (September 2004)
3.24 Adhesive and Mastic Remover
3.24.1 Frammar BEAN-e-doo Mastic Remover
BEAN-e-doo Mastic Remover is a soybean based product used to remove asbestos mastic, carpet
mastic, and ceramic tile mastic. The user pulls up the flooring, pours BEAN-e-doo onto the
surface, and after about one h, scrapes off the softened mastic. BEAN-e-doo has no odor and
rinses away with water.
For the BEES system, the function of mastic remover is removing 9.29 m2 (100 ft2) of mastic
under vinyl or similar flooring over a period of 50 years.
The detailed environmental performance data for this product may be viewed by opening the file
J1010A.DBF under the File/Open menu item in the BEES software.
Flow Diagram
The flow diagram below shows the major elements of the production of this product, as it is
currently modeled for BEES.
266
-------
BEAN-e-doo Mastic Remover
Fertilizer
production
Agrichemicals
production
Fertilizer
production
Agrichemicals
production
Figure 3.66: BEAN-e-doo Mastic Remover System Boundaries
Raw Materials
BEAN-e-doo is made up of the materials shown in the Table below.
Table 3.145: BEAN-e-doo Mastic Remover Constituents
Constituent
Mass Fraction (%)
Methyl soyate
Nonionic surfactants236
d-Limonene
85
14
1
Data for methyl soyate originates with soybean production data from the U.S. LCI Database.
Data for the production of soybean oil and its further transformation into methyl soyate comes
from a National Renewable Energy Laboratory LCA study on biodiesel use in an urban bus.237
While data for production of the nonionic surfactant compounds in the product is unavailable,
data for producing alcohol ethoxylate (AE) is used as a proxy.238 D-Limonene is the major
component of oil extracted from citrus rind; for production data purposes it is considered a
coproduct of orange production. As such, it is assumed to comprise 0.5 % of the total mass of
useful orange products, which include orange juice, cattle peel feed, and alcohol. Orange data
comes from a variety of sources.239'240'241
236 Names of surfactants not released to protect the confidentiality of company data.
237 Sheehan, J. et al, NREL/SR-580-24089 (Washington, DC: US Department of Agriculture and US
Department of Energy, May 1998).
238 Dall'Acqua, S., et al., Report #244 (St. Gallen: EMPA, 1999).
239 National Agricultural Statistics Service, 2005. Found at:
267
-------
Manufacturing
Energy Requirements and Emissions. Manufacture of BEAN-e-doo consists of pumping the
components together into a 1.14 m3 (300 gal) container, then draining the container. Production
energy is required for pumping, but no heating of the product is required. For each 3.8 L (1 gal)
of product, 0.004 MJ (0.001 kWh) is the estimated energy requirement based on the size of the
pump. Electricity is modeled using the U.S. average electric grid from the U.S. LCI Database.
Approximately 0.04 m3 (10 gal) of water is included in the model to account for rinsing the tank
between several production batches.
Transportation. Methyl soy ate is transported approximately 322 km (200 mi) to the BEAN-e-
doo facility. D-limonene is transported approximately 1931 km (1 200 mi), and the surfactants
are transported about 64 km (40 mi). All materials are assumed to be transported by diesel truck,
which is modeled based on the U.S. LCI Database.
Transportation
Diesel trucking is the mode of product transport from the BEAN-e-doo facility to the customer.
The transportation distance is, by default, 805 km (500 mi), but this distance can be adjusted by
the BEES user. Diesel trucking is modeled based on the U.S. LCI Database.
Use
According to manufacturer instructions for vinyl mastic removal, one gal of BEAN-e-doo may
be applied to up to 18.6 m2 (200 ft2) of flooring, so 0.002 m3 (0.5 gal) is modeled for removing
9.29 m2 (100 ft2) of mastic. It is assumed that BEAN-e-doo is applied twice to remove mastic
over a period of 50 years. Data on water requirements or potential effluents from rinsing the
product are not available.
End of Life
After BEAN-e-doo has been applied and mastic removed, they are both assumed to be disposed
of in a landfill. However, while they are disposed together, only the mass of the BEAN-e-doo is
accounted for at end of life.
References
Life Cycle Data
National Renewable Energy Laboratory (NREL): U.S. Life-Cycle Inventory Database. 2005.
Golden, CO. Found at: http://www.nrel.gov/lci/database.
PRe Consultants: SimaPro 6.0 LCA Software. 2005. The Netherlands.
Sheehan, J. et al., Life Cycle Inventory of Biodiesel and Petroleum Diesel for Use in an Urban
Bus, NREL/SR-5 80-24089 (Washington, DC: U.S. Department of Agriculture and U.S.
Department of Energy, May 1998).
Dall'Acqua, S., et al., Life Cycle Inventories for the Production of Detergent Ingredients,
Report #244 (St. Gallen: EMPA, 1999).
http://www.nass.usda.gov:8080/QuickStats/index2.jsp.
240 Reposa, J. Jr. and Pandit, A., "Inorganic nitrogen, phosphorus, and sediment losses from a citrus grove during
stormwater runoff (Melbourne, FL: Civil Engineering Program, Florida Institute of Technology). Found at:
http://www.stormwaterauthority.org/assets/023PLreposacitrus.pdf.
241 Extrapolation of data for agricultural products from the U.S. LCI Database.
268
-------
National Agricultural Statistics Service, 2005. Found at:
http://www.nass.usda.gov: 8080/OuickStats/index2.jsp
Reposa, J. Jr. and Pandit, A., "Inorganic nitrogen, phosphorus, and sediment losses from a
citrus grove during stormwater runoff (Melbourne, FL: Civil Engineering Program, Florida
Institute of Technology, date unknown). Found at:
http://www.stormwaterauthoritv.org/assets/023PLreposacitrus.pdf
Industry Contacts
Dan Brown, Franmar Chemical, Inc. (September 2004)
3.24.2 Nano Green Mastic Remover
See documentation on both Nano Green products under Floor Stripper.
269
-------
270
-------
4. BEES Tutorial
To select environmentally-preferred, cost-effective building products, follow three main steps:
1. Set your study parameters to customize key assumptions
2. Define the alternative building products for comparison. BEES results may be
computed once alternatives are defined.
3. View the BEES results to compare the overall, environmental, and economic
performance scores for your alternatives.
4.1 Setting Parameters
Select Analysis/Set Parameters from the BEES Main Menu to set your study parameters. A
window listing these parameters appears, as shown in Figure 4.1. Move around this window by
pressing the Tab key.
BEES uses importance weights to combine environmental and economic performance measures
into a single performance score. If you prefer not to weight the environmental and economic
performance measures, select the "no weighting" option. In this case, BEES will compute and
display only disaggregated performance results.
Assuming you have chosen to weight BEES results, you are asked to enter your relative
importance weights for environmental versus economic performance. These values must sum to
100. Enter a value between 0 and 100 for environmental performance reflecting your percentage
weighting. For example, if environmental performance is all-important, enter a value of 100. The
corresponding economic importance weight is automatically computed. Next you are asked to
select your relative importance weights for the environmental impact categories included in the
BEES environmental performance score: Global Warming, Acidification, Eutrophication, Fossil
Fuel Depletion, Indoor Air Quality, Habitat Alteration, Water Intake, Criteria Air Pollutants,
Smog, Ecological Toxicity, Ozone Depletion, and Human Health. You are presented with four
sets of alternative weights. You may choose to define your own set of weights or to select a
built-in weight set derived from an EPA Science Advisory Board study, judgments by a BEES
Stakeholder Panel, or a set of equal weights.242 Press View Weights to display the impact
category weights for all four weight sets, as shown in Figure 4.2. If you select the user-defined
weight set, you will be asked to enter weights for all impacts under analysis, as shown in Figure
4.3. These weights must sum to 100.
242 So that the set of equal weights would appropriately sum to 100, individual weights have been rounded up or
down. These arbitrary settings may be changed by using the user-defined weighting option.
271
-------
Analysis Parameters
F" No Weighting
Environmental vs. Economic Performance Weights
Environmental -
Performance [%\. H
Economic Performance
vs- m-
Environmental Impact Category Weights
C" User-Defined Set I
f~ EPA Scientific Advisory Board
T BEES Stakeholder Panel
<•" Equal Weights
View Weights About Weights
Ok
Discount Rate (%}: (Excluding
Inflation) 3.0
Cancel
Help
Figure 4.1 Setting Analysis Parameters
• Environmental Impact Category Weights [X_)
Weight Set
User-Defined
EPA Science Advisory Board-based
BEES Stakeholder Panel
Equal Weights
Globalwarm
9
16
29
9
Acidifcatn
9
5
3
9
Eutraphctn
9
5
6
9
FosFuelDep
9
5
10
9
lndoor_Air
8
11
3
8
Habit_altn
8
16
6
8
Watecjntk
8
3
8
8
Ctit_Air_P
8
6
9
8
Smog
8
6
4
8
Ecolog_To>
8
11
7
8
0:one_Depl
8
5
2
8
Human_Hlth]
8
11
13
8
Figure 4.2 Viewing Impact Category Weights
272
-------
Environmental Impact Category Weights
Weight Set [user-Defined
Global Warming
Acidification
Eutrophication
Fossil Fuel Depletion
Indoor Air Quality
Habitat Alteration
Water Intake
Criteria Air Pollutants
Smog
Ecolog Toxicity
Ozone Depletion
Human Health
SUM
Cancel
Help
Figure 4.3 Entering User-Defined Weights
Finally, enter the real (excluding inflation) discount rate for converting future building product
costs to their equivalent present value. All future costs are converted to their equivalent present
values when computing life-cycle costs. Life-cycle costs form the basis of the economic
performance scores. The higher the discount rate, the less important to you are future building
product costs such as repair and replacement costs. The maximum value allowed is 20 %. A
discount rate of 20 % would value each dollar spent 50 years hence as only $0.0001 in present
value terms. The 2006 rate mandated by the U.S. Office of Management and Budget for most
Federal projects, 3.0 %, is provided as a default value.243
243 U.S. Office of Management and Budget (OMB) Circular A-94, Guidelines and Discount Rates for Benefit-
Cost Analysis of Federal Programs, Washington, DC, October 27, 1992 and OMB Circular A-94, Appendix C,
Washington, DC, January 2007
273
-------
Building Element for Companion U
Major Group Element
Interiors
OK
Cancel
Group Element
Interior Finishes
Help
Individual Element
Floor Coverings
View Product List
Figure 4.4 Selecting Building Element for BEES Analysis
4.2 Defining Alternatives
Select Analysis/Define Alternatives from the Main Menu to choose the building products you
want to compare. A window appears as in Figure 4.4. Selecting alternatives is a two-step
process.
1. Select the specific building element for which you want to compare
alternatives. Building elements are organized using the hierarchical structure
of the ASTM standard UNIFORMAT II classification system: by Major
Group Element, Group Element, and Individual Element.244 Click on the
down arrows to display the complete lists of available choices at each level of
the hierarchy. For a listing BEES products included in each building element,
click View Product List.
BEES 4.0 contains environmental and economic performance data for over
230 products across a wide range of building elements including beams,
columns, roof sheathing, exterior wall finishes, wall insulation, framing, roof
coverings, partitions, ceiling finishes, interior wall finishes, floor coverings,
chairs, and parking lot paving. Press Ok to select the choice in view.
International, Standard Classification for Building Elements and Related Sitework— UNIFORMAT II,
ASTM Designation E1557-05, West Conshohocken, PA, 2005.
274
-------
Select Product Alternatives
Anonymous Carpet Tile Product
EPS Capri Broadloom Carpet
EPS Scan Broadloom Carpet
BPS UPC Carpet Tile
CSA ER3 Cushion Roll Goods
C&A ER3 Modular Tile
C&A Ethos Cushion Roll Goods
CSA Ethos Modular Tile
Forbo Linoleum
Forbo Linoleum/No-VQC Adhsv
Generic Ceramic Tie w/ Recvced G ass
Generic Composite Marble Tile
Generic Linoleum Flooring
Generic Nylon Carpet
Generic Terrazzo
Generic Vinyl Composition Tile
Generic Wool Carpet
IFC Entropy Carpet Tile, Climate Neutral
IFC Sabi Carpet Tile, Climate Neutral
IFC T ransformationCarpetT ile,ClimateN eut
JU Industries Certificate Brdlm Carpet
Mohawk Meritage Broadloom Carpet
Mohawk Regents Row Broadloom Carpet
Natural Cork Floating Floor Plank
Natural Cork Parquet Tile
Compute BEES Results
Cancel
Help
Figure 4.5 Selecting Building Product Alternatives
Transportation
Generic Ceramic Tile w/ Recycled Glass
Transportation Distance from Manufacture to Use:
View Product Documentation
miles (805 kilometers)
Ok
Figure 4.6 Setting Transportation Parameters
275
-------
2. Once you have selected the building element, you are presented with a
window of product alternatives available for BEES scoring, such as in Figure
4.5. Select an alternative with a mouse click. After selecting each alternative,
you will be presented with a window, such as in Figure 4.6, asking for the
distance required to transport the product from the manufacturing plant to
your building site.245 If the product is exclusively manufactured in another
country (e.g., linoleum flooring), this setting should reflect the transportation
distance from the U.S. distribution facility to your building site (transport to
the distribution facility has already been built into the BEES data).
If you have already set your study parameters, press Compute BEES Results to compute and
display the BEES environmental and economic performance results.
4.3 Viewing Results
Once you have set your study parameters, defined your product alternatives, and computed
BEES results, BEES displays the window for selecting BEES reports illustrated in Figure 4.7.
By default, the three summary graphs shown in Figures 4.8, 4.9, and 4.10 are selected for display
or printing. Press Display to view the three graphs. For all BEES graphs, the larger the value,
the worse the performance. Also, all BEES graphs are stacked bar graphs, meaning the height of
each bar represents a summary performance score consisting of contributing scores represented
as its stacked bars.
1. The Overall Performance Results graph displays the weighted environmental
and economic performance scores and their sum, the overall performance
score. If you chose not to weight, this graph is not available.
2. The Environmental Performance Results graph displays the weighted
environmental impact category scores and their sum, the environmental
performance score. Because this graph displays scores for unit quantities of
individual building products that have been normalized (i.e., placed on a
common scale) by reference to total U.S. impacts, they appear as very small
numbers. For a primer on interpreting BEES environmental performance
scores, refer to Appendix B. If you chose not to weight, this graph is not
available.
3. The Economic Performance Results graph displays the first cost, discounted
future costs and their sum, the life-cycle cost.
245 If you have chosen the wall insulation or exterior wall finish elements, you will first be asked for parameter
values so that the products' influence on heating and cooling energy use over the 50-year study period can be
properly estimated. If you have chosen roof coverings and installation will be in a U.S. Sunbelt climate, you will be
asked for parameter values that will permit accounting for 50-year heating and cooling energy use based on roof
covering color.
276
-------
Select BEES Reports
P Summary Table
S ummary G raphs
!• Overall Performance
R? Environmental Performance
P Economic Performance
D etailed G raphs
by
P
P
P
l~
P
r
f~
P
r
r~
P
Life-Cycle Stage
Environmental Performance
Global Warming
Acidification
Eutrophication
Fossil Fuel Depletion
Indoor Air Quality
Habitat Alteration
Water Intake
Criteria Air Pollutants
Ecological Toxicity
P Human Health Cancer
P Human Health Noncancer
Ozone Depletion
Smog
by Environmental Flow
P Global Warming
P Acidification
P Eutrophication
P Fossil Fuel Depletion
P Indoor Air Quality
P Habitat Alteration
P Water Intake
P Criteria Air Pollutants
P Ecological Toxicity
p P Human Health Cancer
P Human Health Noncancer
P Ozone Depletion
P Smog
Embodied Energy
P by Fuel Renewability
P Fuel Energy vs. Feedstock Energy
P All Tables in One
P Parameter Settings
Figure 4.7 Selecting BEES Reports
211
-------
CH Economic Performance
I Environmental Performance
Note: Lowei values .ire better
o
o
CO
Overall Performance
10 -
CeramicTile vu/ Glass Terrazzo Nylon Carpet Brdlm
Linoleum Nylon Carpet Tile
Alternatives
Category
Economic Perform. --50%
Environ. Perform. --50%
Sum
Tile/Glass
9.3
10.5
19.8
Linoleum
4.6
2.7
7.3
Terrazzo
22.9
4.4
27.3
NylonTile
7.5
13.5
21.0
NylonBidlin
5.8
13.9
24.7
Figure 4.8 Viewing BEES Overall Performance Results
278
-------
Environmental Performance
Note: Lowe
1 1 Acidification
• Crii Air Pollutants
1 Ecological Toxicity
1 I Eutrophication
CH Fossil Fuel Depletion
CH Global Warming
D Habitat Alteration
• Human Health
CH Indoor Air
1 Ozone Depletion
CH Smog
• water Intake
rvalues are hetter
Category
Acidification-9%
Crit. Air Pollutants-8%
Ecolog. Toxicity-8%
Eutrophication-9%
Fossil Fuel Depl.-9%
Global Warming-9%
Habitat Alteration--8%
sf
pts/unit
0.0400 -
n mnn ^
4)
9 origin - .,••'
V) '
0.0100 1
CeramioTile
Tile Glass Linoleum
0.0000 0.0000
0.0001 0.0001
0.0008 0.0007
0.0002 0.0010
0.0011 0.0006
0.0009 0.0005
0.0000 0.0000
I
i
I
^
F
L
^^
bj"
=
m
^^^m
^
_^_ ^_
\A
j \^_
vw1 Glass Terrazzo Nylon Carpet Brdlm
Linoleum Nylon Carpet Tile
Alternatives
Teiuizzo NylonTile NylonBiillm
0.0000
0.0002
0.0007
0.0007
0.0017
0.0009
0.0000
0.0000
0.0003
0.0013
0.0019
0.0035
0.0013
0.0000
0.0000
0.0003
0.0009
0.0031
0.0043
0.0021
0.0000
Press PageDown for nioie lesults...
Figure 4.9 Viewing BEES Environmental Performance Results
279
-------
Economic Performance
PV $/unit
First Cost
Future Cost
o
U
-
>
^
3>
20.00
10.00
0.00
I
I
CeramicTile i.iu' Glass Terrazzo Nylon Carpet Brdlm
Linoleum Nylon Carpei Tile
Alternatives
Ciitegoiy
First Cost
Future Cost-- 3.0%
Sum
Tile- Glass
9.55
0.00
9.55
Linoleum
3.56
1.20
4.76
Ten.izzo
23.59
0.00
23.59
NylonTile
3.5S
4.1S
7.76
NyloiiBidhn
2.13
3.81
5.94
Figure 4.10 Viewing BEES Economic Performance Results
BEES results are derived by using the BEES model to combine environmental and economic
performance data using your study parameters. The method is described in section 2. The
detailed BEES environmental and economic performance data, documented in section 3, may be
browsed by selecting File/Open from the Main Menu.
From the window for selecting BEES reports, you may choose to display a summary Table
showing the derivation of summary scores, graphs depicting results by life-cycle stage and by
contributing flow for each environmental impact category, graphs depicting embodied energy
performance, and an All Tables in One report giving all the detailed results in a single tabular
report. Figures 4.11 through 4.15 illustrate each of these options.246
Once you have displayed any BEES report, you may select additional reports for display by
selecting Tools/Select Reports from the menu.247 To compare BEES results based on different
parameter settings, either select Tools/Change Parameters from the menu, or if the Summary
Table is in focus, press the Change Parameters button. Change your parameters, and press Ok.
246 If you Set Analysis Parameters to use the BEES Stakeholder Panel weight set to interpret life-cycle impact
assessment results, then impact-based results may be viewed separately for cancerous and noncancerous health
effects. For compatibility with the other BEES 4.0 weighting schemes, however, these results are weighted and
combined into a single Human Health impact for display of BEES Environmental Performance Scores. For more
information on the BEES Stakeholder Panel weight set, see section 2.1.4.
247 This feature is not available from the menu displayed with the BEES Summary Table.
280
-------
You may now display reports based on your new parameters. Then you may find it convenient to
view reports with different parameter settings side-by-side by selecting Window/Tile from the
menu. Note that your parameter settings are displayed on the Table corresponding to each graph.
Print any BEES report from the Print menu item. Note that neither the Print to File option of the
printing setup window nor the Export menu item are functional in BEES.
Embodied Energy
While the environmental impacts from energy consumption and combustion already are
accounted for throughout the BEES results by environmental impact category, BEES reports
embodied energy results for informational purposes. BEES classifies and reports total embodied
energy in two ways: (1) by fuel and feedstock energy and (2) by fuel renewability.248
The first classification system uses the energy accounting categories of fuel energy and
feedstock energy. Feedstock energy is the energy content of fuel resources extracted from the
earth, while fuel energy is the amount of energy that is released when fuels are burned. When
fuel resources such as petroleum and natural gas are used as material inputs (e.g., as feedstocks
for the manufacture of polystyrene resin), then the energy value remains in the feedstock
category. When extracted fuel resources are transformed into fuels and burned for energy,
however, most of the feedstock energy is transformed into industrial process or transportation
energy. This moves the quantity of combustion energy from the feedstock category into the fuel
category. Because less than 100 % of the inherent energy value of extracted resources remains
after fuel converting processes and combustion, a small amount of energy remains in the
feedstock category. In general, biobased products and plastics will generate higher BEES
feedstock energy values because there is potential energy "embodied" in the system. A rubber
tire, for example, will have feedstock energy in the tire itself and fuel energy from its
production. If, after use, the tire is then sent to a cement kiln to recover its energy as a method of
"disposing" of the used tire, then that feedstock (potential) energy in the tire is converted to that
amount of fuel to the cement kiln. In that case, the feedstock energy in the tire has been
converted to fuel energy.
Total embodied energy is also classified and reported using the energy accounting categories of
renewable energy and non-renewable energy. Energy derived from fossil fuels such as
petroleum, natural gas, and coal is classified as non-renewable, while energy from all other
sources (hydropower, wind, nuclear, geothermal, biomass) is classified as renewable.
4.4 Browsing Environmental and Economic Performance Data
The BEES environmental and economic performance data may be browsed by selecting
File/Open from the Main Menu. Environmental data files are specific to products, while there is
a single economic data file, LCCOSTS.DBF, with cost data for all products. Some
environmental data files map to a product in more than one application, while the economic data
typically vary for each application. Table 4.1 lists the products by environmental data file name
(all with the .DBF extension) and by code number within the economic performance data file
LCCOSTS.DBF.
248 Embodied energy definitions documented by Four Elements, LLC.
281
-------
The environmental performance data files are similarly structured. The first column in all these
files, XPORT, shows the default transportation distance from manufacture to use (in mi). The
second column lists a number of environmental flows. Flows marked "(r)" are raw materials
inputs, "(a)" air emissions, "(ar)" radioactive air emissions, "(s)" releases to soil, "(w)" water
effluents, "(wr)" radioactive water effluents, and "E" energy usage. All quantities are expressed
in terms of the product's functional units, typically 0.09 m2 (1 ft2) of product service for 50
years.249 The column labeled "Total" is the primary data column, giving total cradle-to-grave
flow amounts. Next are columns giving flow amounts for each product component, followed by
columns giving flow amounts for each life-cycle stage. The product component columns roughly
sum to the total column, as do the life-cycle stage columns. The IAINDEX column is for internal
BEES use.
The economic performance data file LCCOSTS.DBF lists for each cost the year of occurrence
(counting from year 0) and amount (in constant 2006 dollars) per functional unit.
Warning: If you change any of the data in the environmental or economic performance data files,
you will need to reinstall BEES to restore the original BEES data.
249 The following BEES product categories have different functional units: Roof Coverings: covering 9.29 m2 (1
square, or 100 ft2) of roof surface for 50 years; Concrete Beams and Columns: 0.76 m3 (1 yd3) of product service for
50 years; Office Chairs: seating for 1 person for 50 years; Adhesive and Mastic Remover: removing 9.29 m2 (100
ft2) of mastic under vinyl or similar flooring over 50 years; Exterior Sealers and Coatings: sealing or coating 9.29
m2 (100 ft2) of exterior surface over 50 years ; Transformer Oils: cooling for one 1 000 kV-A transformer for 30
years; Fertilizer: fertilizing 0.40 ha (1 acre) for 10 years; Carpet Cleaners: cleaning 92.9 m2 (1 000 ft2) of carpet
once; Floor Stripper: removing three layers of wax and one layer of sealant from 9.29 m2 (100 ft2) of hardwood
flooring once; Roadway Dust Control: controlling dust from 92.9 m2 (1 000 ft2) of surface area once; Bath and Tile
Cleaner: using 3.8 L (1 gal) of ready-to-use cleaner once; Glass Cleaners: using 3.785 m3(l 000 gal) of ready-to-use
glass cleaner once; and Grease and Graffiti Remover: using 3.8 L (1 gal) of grease and graffiti remover once.
282
-------
Potential
Environmental
Impact
Acidification
jiteria Air Pollutants
Ecological Toxicity
Eutrophication
ossil Fuel Depletion
Global Warming
Habitat Alteration
Indoor Air Quality
Ozone Depletion
Smog
Water Intake
Human Health-All
Economic
Impact
First Cost
Future Cost
Units
Raw Result:*
Tile/Glass Linoleum Terrazzo NylonTile NylonBrdlm
1.42e-01 4.14e-01 6.47e-01 6.73e-01
8.48e+00 |738e+00 7.19e+00 l.35e+01 a69e+00
4.40e-01 |217e+00 11 46e+00 I4.13e+00 |6.55e-fOO
4.196400 |242e400 16 54etOO h.37e+01 |l.69e+01
Tile/Glass Linoleum
Pass i~a56~~
Terrazzo NylonTile NylonGrdlrn
23.59
3.58
2.13
PV$
0.00
1.20
0.00
4.18
3.81
Life-Cycle Cost
Discount Rate (%}
4.76
"23.59 f7.76~~p5.94
Note: Lower values are better
*EKpressed in given impact units per functional unit of product
Weighting
ffl
Equal
2.51e+03 J1.338+03 I2.87e+03 |5.21e+03 6.00e+03
3.70e-02 1.20e-01 O.OOe+00 6.35e+00 5.48e+01
O.OOe+DQ OOOe+00 O.OOe+00 0.00e+00 0.00e+00
1.31e+01 1 20e+01 2.03e+01 2.64e+01 3.02e+01
1.51e+01 4.46e+01 9.52e+01 2.24e+02 4.21e+02
5.05e+05 1.92e4(M 3.99e+04 3.12e+05 8.73et04
Total
Normalized Results"
Linoleum Terrazzo NylonTile
Potential Overall Impact*"
Tile/Glass Linoleum Terrazzo NylonTile NylonBrdlrn
19.8
27.3
21.0
KXExpressed in penalty points per functional unit of product
***Expfessed in dimensionless score ranging from 0 to 100 penalty points
Figure 4.11 Viewing BEES Summary Table
283
-------
Global Warming by Life-Cycle Stage
g CO2/unit
CH Raw Materials Acquisition
l Manufacturing
CH Transportation
CeramieTile w/ GI ass Terrazzo NylonCarpetBrdlm
Linoleum Nylon Carpet Tile
Alternatives
Note: Lowei values aie better
Categoiy
Tile/Glass
Linoleum
Teiuizzo
NylonTile NylonBitllrn
1. Raw Materials
1603
650
2497
4540
5568
2. Manufacturing
701
639
376
321
3. Transportation
212
43
173
232
114
4. Use
5. End of Life
Sum
2515
1331
2671
5208
6003
Figure 4.12 Viewing BEES Environmental Impact Category Performance Results by Life-
Cycle Stage
284
-------
Acidification by Flow
mmonia
D Hydrogen Chloride
L~H Hydrogen Cyanide
Hydrogen Fluoride
I Hydrogen Sulfide
D Nitrogen Oxides
I Sulfur Oxides
I SulfuricAcid
mg H+/unit
ni
1 2,000.00
|
3- 1,500.00
111
c
•^ 1,000.00
01
n
-§ 500.00
£
0.00
CeramicTile iro/ Glass Terrazzo Nylon Carpet Brdlm
Linoleum Nylon Carpet Tile
Alternatives
Note: Lower values me better
Category
Tile Glass
Linoleum
Terrazzo
NylonTile
NylonBidlm
(a) Ammonia (NH3)
0.64
58.84
0.44
55.89
36.28
(a) Hydrogen Chloride (HCI)
2.90
3.76
7.64
12.79
10.69
(a) Hydrogen Cyanide (HCN)
0.00
0.04
0.00
0.00
0.00
(a) Hydrogen Fluoride (HF)
4.31
0.73
0.89
2.42
1.31
(a) Hydrogen Sulfide (H2S)
0.00
0.24
0.08
0.19
0.12
(a) Nitrogen Oxides (NOx as N02
319.12
297.22
576.58
683.13
817.63
(a) Sulfur Oxides (SOx as S02)
634.88
246.27
665.35
1339.63
1324.83
(a) Sulfuric Acid (H2S04)
0.00
0.00
0.07
0.00
0.00
Press PageDown for more results...
Figure 4.13 Viewing BEES Environmental Impact Category Performance Results by Flow
285
-------
Embodied Energy by Fuel Usage
MJ/unit
D Feedstock Energy
Fuel Energy
c
Ul
T3
Hi
ja
E
UJ
CeramicTile IAI/ Glass
Linoleum
Terrazzo Nylon Carpet Brd I m
Nylon Carpet Tile
Alternatives
Categoiy
Tile/Glass
Linoleum
Termzzo
NylonTile
NylonBrdlm
Feedstock Energy
8.64
12.21
15.70
44.22
56.09
Fuel Energy
23.60
16.08
21.40
65.94
75.99
Sum
32.24
28.29
37.10
110.16
132.08
Figure 4.14 Viewing BEES Embodied Energy Results
Criteria Air Pollutants I
Category
(a) Nitrogen Oxides (NOx as N02
(a) Parliculates (greater than
(a) Particulates (PM 10)
(a) Parliculates (unspecified)
(a) Sulfur Oxides (SOx as S02)
t>y Flow (m
TileGkiss
0.02
0.00
0.03
0.06
0.17
icro disabi
Linoleum
0.02
0.00
0.02
0.04
0.07
lity-adjust<
Teimzzo
0.03
0.00
0.01
0.19
0.18
;d life year
NylonTile
0.04
0.00
0.01
0.23
0.37
s/unit)
NylonBi
-------
Table 4.1 BEES Products Keyed to Environmental and Economic Performance Data Codes
MAJOR ELEMENT
Group Element
SUBSTRUCTURE
Foundations
SUBSTRUCTURE
Basement Construction
SHELL
Superstructure
Individual Element
BEES Product
Environ-
mental
Data File
Name
Economic
Data Code
Slab On Grade
Generic 100 % Portland Cement
Generic 15 % Fly Ash Cement
Generic 20 % Fly Ash Cement
Generic 20 % Slag Cement
Generic 35 % Slag Cement
Generic 50 % Slag Cement
Generic 5 % Limestone Cement
Generic 10 % Limestone Cement
Generic 20 % Limestone Cement
Lafarge Silica Fume Cement
Anonymous IP Cement Product
Lafarge NewCem Slag Cement (20 %)
Lafarge NewCem Slag Cement (35 %)
Lafarge NewCem Slag Cement (50 %)
Generic 35 % Fly Ash Cement
Lafarge Portland Type I Cement
A1030A
A1030B
A1030C
A1030D
A1030E
A1030F
A1030G
A1030H
A1030I
A1030J
A1030K
A1030L
A1030M
A1030N
A1030O
A1030P
A1030,AO
A1030,BO
A1030,CO
A1030,DO
A1030,EO
A1030,FO
A1030,GO
A1030,HO
A1030,IO
A1030,JO
A1030,KO
A1030,LO
A1030,MO
A1030,NO
A1030,OO
A1030,PO
Basement Walls
Generic 100 % Portland Cement
Generic 15 % Fly Ash Cement
Generic 20 % Fly Ash Cement
Generic 20 % Slag Cement
Generic 35 % Slag Cement
Generic 50 % Slag Cement
Generic 5 % Limestone Cement
Generic 10 % Limestone Cement
Generic 20 % Limestone Cement
Lafarge Silica Fume Cement
Anonymous IP Cement Product
Lafarge NewCem Slag Cement (20 %)
Lafarge NewCem Slag Cement (35 %)
Lafarge NewCem Slag Cement (50 %)
Lafarge BlockSet
Lafarge Portland Type I Cement
A2020A
A2020B
A2020C
A2020D
A2020E
A2020F
A2020G
A2020H
A2020I
A2020J
A2020K
A2020L
A2020M
A2020N
A2020O
A2020P
A2020,AO
A2020,BO
A2020,CO
A2020,DO
A2020,EO
A2020,FO
A2020,GO
A2020,HO
A2020JO
A2020,JO
A2020,KO
A2020XO
A2020,MO
A2020,NO
A2020,OO
A2020,PO
Beams
Generic 100 % Portland Cement 4KSI
Generic 15 % Fly Ash Cement 4KSI
Generic 20 % Fly Ash Cement 4KSI
Generic 20 % Slag Cement 4KSI
Generic 35 % Slag Cement 4KSI
Generic 50 % Slag Cement 4KSI
Generic 5 % Limestone Cement 4KSI
Generic 10 % Limestone Cement 4KSI
Generic 20 % Limestone Cement 4KSI
Generic 100 % Portland Cement 5KSI
Generic 15 % Fly Ash Cement 5KSI
Generic 20 % Fly Ash Cement 5KSI
B1011A
B1011B
B1011C
B1011D
B1011E
B1011F
B1011G
B1011H
B1011I
B1011J
B1011K
B1011L
B1011,AO
B1011,BO
B1011,CO
B1011,DO
B1011,EO
B1011,FO
B1011,GO
B1011,HO
B1011JO
B1011JO
B1011,KO
B1011,LO
287
-------
SHELL
Superstructure
SHELL
Superstructure
SHELL
Exterior Enclosure
SHELL
Generic 20 % Slag Cement 5KSI
Generic 35 % Slag Cement 5KSI
Generic 50 % Slag Cement 5KSI
Generic 5 % Limestone Cement 5KSI
Generic 10 % Limestone Cement 5KSI
Generic 20 % Limestone Cement 5KSI
Lafarge Silica Fume Cement 4KSI
Anonymous 4KSI Product
Lafarge NewCem Slag Cement 4KSI (20 %)
Lafarge NewCem Slag Cement 4KSI (35 %)
Lafarge NewCem Slag Cement 4KSI (50 %)
Lafarge Silica Fume Cement 5KSI
Anonymous 5KSI Product
Lafarge NewCem Slag Cement 5KSI (20 %)
Lafarge NewCem Slag Cement 5KSI (35 %)
Lafarge NewCem Slag Cement 5KSI (50 %)
Lafarge Portland Type I Cement 4KSI
Lafarge Portland Type I Cement 5KSI
B1011M
B1011N
B1011O
B1011P
B1011Q
B1011R
B1011S
B1011T
B1011U
B1011V
B1011W
B1011X
B1011Y
B1011Z
B1011AA
B1011BB
B1011CC
B1011DD
B1011,MO
B1011,NO
B1011,OO
B1011,PO
B1011,QO
B1011,RO
B1011,SO
B1011,TO
B1011,UO
B1011,VO
B1011,WO
B1011,XO
B1011,YO
B1011,ZO
B1011,AA
B1011,BB
B1011,CC
B1011,DD
Columns
Generic 100 % Portland Cement 4KSI
Generic 15 % Fly Ash Cement 4KSI
Generic 20 % Fly Ash Cement 4KSI
Generic 20 % Slag Cement
Generic 35 % Slag Cement 4KSI
Generic 50 % Slag Cement 4KSI
Generic 5 % Limestone Cement 4KSI
Generic 10 % Limestone Cement 4KSI
Generic 20 % Limestone Cement 4KSI
Generic 100 % Portland Cement 5KSI
Generic 15 % Fly Ash Cement 5KSI
Generic 20 % Fly Ash Cement 5KSI
Generic 20 % Slag Cement 5KSI
Generic 35 % Slag Cement 5KSI
Generic 50 % Slag Cement 5KSI
Generic 5 % Limestone Cement 5KSI
Generic 10 % Limestone Cement 5KSI
Generic 20 % Limestone Cement 5KSI
Lafarge Silica Fume Cement 4KSI
Anonymous 4KSI Product
Lafarge NewCem Slag Cement 4KSI (20 %)
Lafarge NewCem Slag Cement 4KSI (35 %)
Lafarge NewCem Slag Cement 4KSI (50 %)
Lafarge Silica Fume Cement 5KSI
Anonymous 5KSI Product
Lafarge NewCem Slag Cement 5KSI (20 %)
Lafarge NewCem Slag Cement 5KSI (35 %)
Lafarge NewCem Slag Cement 5KSI (50 %)
Lafarge Portland Type I Cement 4KSI
Lafarge Portland Type I Cement 5KSI
B1012A
B1012B
B1012C
B1012D
B1012E
B1012F
B1012G
B1012H
B1012I
B1012J
B1012K
B1012L
B1012M
B1012N
B1012O
B1012P
B1012Q
B1012R
B1012S
B1012T
B1012U
B1012V
B1012W
B1012X
B1012Y
B1012Z
B1012AA
B1012BB
B1012CC
B1012DD
B1012,AO
B1012,BO
B1012,CO
B1012,DO
B1012,EO
B1012,FO
B1012,GO
B1012,HO
B1012,IO
B1012,JO
B1012,KO
B1012,LO
B1012,MO
B1012,NO
B1012,OO
B1012,PO
B1012,QO
B1012,RO
B1012,SO
B1012,TO
B1012,UO
B1012,VO
B1012,WO
B1012,XO
B1012,YO
B1012,ZO
B1012,AA
B1012,BB
B1012,CC
B1012,DD
Roof Sheathing
Generic Oriented Strand Board Sheathing
Generic Plywood Sheathing
B1020A
B1020B
B1020,AO
B1020,BO
Exterior Wall Systems
CENTRIA Formawall Insulated Composite Panel
B2010A
B2010,AO
Exterior Wall Finishes
Generic Brick & Mortar
B2011A
B2011,AO
288
-------
Exterior Enclosure
SHELL
Exterior Enclosure
SHELL
Exterior Enclosure
SHELL
Exterior Enclosure
SHELL
Exterior Enclosure
SHELL
Roofing
SHELL
Roofing
SHELL
Generic Stucco
Generic Aluminum Siding
Generic Cedar Siding
Generic Vinyl Siding
Trespa Meteon Panels
Anonymous Brick & Mortar Product 1
Headwaters Scratch & Brown Stucco Type S
Headwaters FRS
Anonymous Brick & Mortar Product 2
Headwaters Masonry Cement Type S
Dryvit EIFS Cladding Outsulation
Dryvit EIFS Cladding Outsulation Plus
B2011B
B2011C
B2011D
B2011E
B2011F
B2011G
B2011H
B2011I
B2011J
B2011K
B2011L
B2011M
B2011,BO
B2011,CO
B2011,DO
B2011,EO
B2011,FO
B2011,GO
B2011,HO
62011,10
620 11, JO
62011,KO
62011,LO
620 11, MO
Wall Insulation
Generic Blown Cellulose R-13
Generic Fiberglass Batt R-19
Generic Fiberglass Batt R-15
Generic Blown Mineral Wool R-13
Generic Fiberglass Batt R-13
Anonymous R-13 Product
Anonymous R-15 Product
Anonymous R-19 Product
B2012A
B2012B
B2012C
B2012D
B2012E
B2012F
B2012G
B2012H
B2012,AO
B2012,BO
B2012,CO
B2012,DO
B2012,EO
B2012,FO
B2012,GO
B2012,HO
Framing
Generic Steel Framing
Generic Wood Framing-Treated
Generic Wood Framing-Untreated
B2013A
B2013B
B2013C
B2013,AO
B2013,BO
B2013,CO
Wall Sheathing
Generic Oriented Strand Board Sheathing
Generic Plywood Sheathing
B1020A
B1020B
B2015,AO
B2015,BO
Exterior Sealers and Coatings
BioPreserve SoyGuard Wood Sealer
Anonymous Masonry Waterproofing Product
B2040A
B2040B
B2040,AO
B2040,BO
Roof Coverings
Generic Asphalt Shingles-Black
Generic Asphalt Shingles-Coral
Generic Asphalt Shingles~Dk Brown
Generic Asphalt Shingles~Dk Gray
Generic Asphalt Shingles-Green
Generic Asphalt Shingles— Lt Brown
Generic Asphalt Shingles~Lt Gray
Generic Asphalt Shingles-Tan
Generic Asphalt Shingles-White
Generic Asphalt Shingles
Generic Clay Tile
Generic Clay Tile-Red
Generic Fiber Cement~Lt Gray/Lt Brown
Generic Fiber Cement Shingles
Generic Fiber Cement— Dk Color
Generic Fiber Cement-Med Color
B3011A
B3011A
B3011A
B3011A
B3011A
B3011A
B3011A
B3011A
B3011A
B3011A
B3011B
B3011B
B3011C
B3011C
B3011C
B3011C
6301 1,AO
6301 1,AO
6301 1,AO
6301 1,AO
6301 1,AO
6301 1,AO
6301 1,AO
6301 1,AO
6301 1,AO
6301 1,AO
63011,60
63011,60
63011,CO
63011,CO
63011,CO
63011,CO
Ceiling Insulation
Generic Blown Cellulose R-38
Generic Fiberglass Batt R-38
Generic Blown Mineral Wool R-38
Generic Blown Fiberglass R-38
Anonymous R-38 Product
B3012A
B3012B
B3012C
B3012D
B3012E
B3012,AO
B3012,BO
B3012,CO
B3012,DO
B3012,EO
Roof Coatings
289
-------
INTERIORS
Interior Construction
INTERIORS
Interior Construction
INTERIORS
Fittings
INTERIORS
Interior Finishes
INTERIORS
Interior Finishes
Prime Coatings Utilithane
B3013A
B3013,AO
Partitions
Generic Gypsum Board
Trespa Virtuon Panels
Trespa Athlon Panels
P&M Plastics Altree Panels
Anonymous Biobased Panel Product 2
C1011A
C3030A
C3030B
C1011D
C1011E
C1011,AO
C1011,BO
C1011,CO
C1011,DO
C1011,EO
Lockers
Trespa Virtuon Panels
Trespa Athlon Panels
C3030A
C3030B
C1030,AO
C1030,BO
Fabricated Toilet Partitions
Trespa Virtuon Panels
Trespa Athlon Panels
C3030A
C3030B
C1031,AO
C1031,BO
Wall Finishes to Interior Walls
Generic Virgin Latex Paint
Generic Consolidated Latex Paint
Generic Reprocessed Latex Paint
C3012A
C3012B
C3012C
C3012,AO
C3012,BO
C3012,CO
Floor Coverings
Generic Ceramic Tile w/ Recycled Glass
Generic Linoleum Flooring
Generic Vinyl Composition Tile
Generic Composite Marble Tile
Generic Terrazzo
Generic Nylon Carpet Tile
Generic Wool Carpet Tile
Generic Nylon Carpet Tile/Low-VOC Adhesive
Generic Wool Carpet Tile/Low-VOC Adhesive
Generic Nylon Carpet Broadloom
Generic Wool Carpet Broadloom
Generic Nylon Carpet Broadloom/Low-VOC
Generic Wool Carpet Broadloom/Low-VOC
C&A ER3 Modular Tile, Climate Neutral
Forbo Linoleum
Anonymous Carpet Tile Product
C&A ER3 Cushion Roll Goods, Climate Neutral
UTT Soy Backed Nylon Broadloom
C&A Ethos Modular Tile, Climate Neutral
C&A Ethos Cushion Roll Goods, Climate Neutral
C&A ER3 Modular Tile
C&A ER3 Cushion Roll Goods
C&A Ethos Modular Tile
C&A Ethos Cushion Roll Goods
IFC Transformation Carpet Tile, Climate Neutral
J&J Industries Certificate Broadloom Carpet
Mohawk Regents Row Broadloom Carpet
Mohawk Meritage Broadloom Carpet
Natural Cork Parquet Tile
Natural Cork Floating Floor Plank
Forbo Linoleum/ No-VOC Adhesive
UTT Soy Backed Nylon Broadloom/Low-VOC
IFC Sabi Carpet Tile, Climate Neutral
EPS Capri Broadloom Carpet
EPS Capri Broadloom, Climate Neutral
EPS Scan Broadloom Carpet
EPS Scan Broadloom Carpet, Climate Neutral
C3020A
C3020B
C3020C
C3020D
C3020E
C3020F
C3020G
C3020I
C3020J
C3020L
C3020M
C3020O
C3020P
C3020Q
C3020R
C3020S
C3020T
C3020U
C3020V
C3020W
C3020X
C3020Y
C3020Z
C3020AA
C3020CC
C3020DD
C3020FF
C3020GG
C3020HH
C3020II
C3020NN
C3020PP
C3020QQ
C3020RR
C3020SS
C3020TT
C3020UU
C3020,AO
C3020,BO
C3020,CO
C3020,DO
C3020,EO
C3020,FO
C3020,GO
C3020,IO
C3020,JO
C3020,LO
C3020,MO
C3020,OO
C3020,PO
C3020,QO
C3020,RO
C3020,SO
C3020,TO
C3020,UO
C3020,VO
C3020,WO
C3020,XO
C3020,YO
C3020,ZO
C3020,AA
C3020,CC
C3020,DD
C3020,FF
C3020,GG
C3020,HH
C3020,II
C3020,NN
C3020,PP
C3020,QQ
C3020,RR
C3020,SS
C3020,TT
C3020,UU
290
-------
INTERIORS
Interior Finishes
EQUIPMENT &
FURNISHINGS
Furnishings
EQUIPMENT &
FURNISHINGS
Furnishings
EQUIPMENT &
FURNISHINGS
Furnishings
BUILDING SITEWORK
Site Improvements
BUILDING SITEWORK
Site Improvements
BUILDING SITEWORK
Site Improvements
BUILDING SITEWORK
Site Electrical Utilities
BUILDING MAINTENANCE
Cleaning Products
BUILDING MAINTENANCE
Cleaning Products
BUILDING MAINTENANCE
Cleaning Products
BUILDING MAINTENANCE
Cleaning Products
BUILDING MAINTENANCE
Cleaning Products
BUILDING REPAIR &
REMODELING
Remodeling Products
EPS UPC Carpet Tile
EPS UPC Carpet Tile, Climate Neutral
IFC Entropy Carpet Tile, Climate Neutral
C3020VV
C3020WW
C3020XX
C3020,W
C3020,WW
C3020,XX
Ceiling Finishes
Trespa Virtuon Panels
Trespa Athlon Panels
C3030A
C3030B
C3030,AO
C3030,BO
Fixed Casework
Trespa Virtuon Panels
Trespa Athlon Panels
C3030A
C3030B
E2010,AO
E2010,BO
Chairs
Herman Miller Aeron Office Chair
Herman Miller Ambi Office Chair
Generic Office Chair
E2020A
E2020B
E2020B
E2020,AO
E2020,BO
E2020,BO
Table Tops, Counter Tops, Shelving
Trespa Toplab Plus Panels
Trespa Athlon Panels
E2021A
C3030B
E2021,AO
E2021,BO
Roadway Dust Control
Anonymous Roadway Dust Control Product
Environmental Dust Control Dustlock
G2015A
G2015B
G2015,AO
G2015,BO
Parking Lot Paving
Generic 100 % Portland Cement
Generic 15 % Fly Ash Cement
Generic 20 % Fly Ash Cement
Asphalt with GSB88 Seal-Bind Maintenance
Generic Asphalt with Traditional Maintenance
Anonymous IP Cement Concrete Product
Lafarge Alpena Type I Cement
G2022A
G2022B
G2022C
G2022D
G2022E
G2022F
G2022G
G2022,AO
G2022,BO
G2022,CO
G2022,DO
G2022,EO
G2022,FO
G2022,GO
Fertilizers
Perdue Micro Start 60 Fertilizer
Four All Seasons Fertilizer
G2060A
G2060B
G2060,AO
G2060,BO
Transformer Oil
Generic Mineral Transformer Oil
Generic Silicone Transformer Oil
Cooper Envirotemp FR3
ABB BIOTEMP
Generic Biobased Transformer Oil
G4010B
G4010C
G4010D
G4010E
G4010F
G4010,BO
G4010,CO
G4010,DO
G4010,EO
G4010,FO
Carpet Cleaners
Anonymous Carpet Cleaning Product
Racine HOST Dry Carpet Cleaning System
H1011A
H1011B
H1011,AO
H1011,BO
Floor Stripper
Nano Green Floor Stripper
H1012A
H1012,AO
Glass Cleaners
Anonymous Glass Cleaning Product
Spartan Green Solutions Glass Cleaner
H1013A
H1013B
H1013,AO
H1013,BO
Bath and Tile Cleaner
Spartan Green Solutions Restroom Cleaner
H1014A
H1014,AO
Grease & Graffiti Remover
Anonymous Graffiti Remover Product 1
Anonymous Graffiti Remover Product 2
VertecBio Gold Graffiti Remover
H1015A
H1015B
H1015C
H1015,AO
H1015,BO
H1015,CO
Adhesive and Mastic Removers
Franmar BEAN-e-doo Mastic Remover
Nano Green Mastic Remover
J1010A
J1010B
J1010,AO
J1010,BO
291
-------
292
-------
5. Future Directions
Development of the BEES tool does not end with the release of version 4.0. Plans to expand and
refine BEES include releasing updates every 24 months with model and software enhancements
as well as expanded product coverage. Listed below are a number of directions for future
research that have been proposed in response to obvious needs, feedback from BEES users, and
peer review comments:250
Proposed Model Enhancements
• Combine building products to permit comparative analyses of entire building components,
assemblies, and ultimately entire buildings
• Conduct and apply research leading to the refinement of impact assessment methods for
indoor air quality, habitat alteration, and water intake
• Characterize uncertainty in the underlying environmental and cost data, and reflect this
uncertainty in BEES performance scores
• Update the BEES LCA methodology in line with future advances in the evolving LCA field
Proposed Data Enhancements
• Continue to solicit cooperation from industry to include more manufacturer-specific building
products in future versions of BEES (this effort is known as the BEES Please program)
• Refine all data to permit U.S. region-specific BEES analyses. This enhancement would yield
BEES results tailored to regional fuel mixes and labor and material markets, and would
permit more accurate assessment of local environmental impacts such as locally scarce
resources (e.g., water)
• Permit flexibility in study period length and in product specifications such as useful lives
• At least every 10 years, revisit products included in previous BEES releases for updates to
their environmental and cost data
• Evaluate biobased products using BEES to assist the Federal procurement community in
carrying out the biobased purchasing mandate, known as BioPreferred, of the 2002 Farm
Security and Rural Investment Act (Public Law 107-171)
Proposed Software Enhancements
• Make streamlined BEES results available on a web-based platform
• Add feature soliciting product quantities from the BEES user to automate the process of
comparing BEES scores across building elements
• Add feature permitting import and export of life cycle inventories
• Add feature permitting integrated sensitivity analysis so that the effect on BEES results of
changes in parameter settings may be viewed on a single graph
250 P. Hofstetter et al., User Preferences for Life-Cycle Decision Support Tools: Evaluation of a Survey of BEES
Users, NISTIR 6874, National Institute of Standards and Technology, Washington, DC, July 2002; and M.A.
Curran et al., BEES 2.0, Building for Environmental and Economic Sustainability: Peer Review Report, NISTIR
6865, National Institute of Standards and Technology, Washington, DC, 2002.
293
-------
294
-------
Appendix A. BEES Computational Algorithms
A.I Environmental Performance
BEES environmental performance scores are derived as follows.
p
EnvScorej = ^ IAScorejk , where
k=l
EnvScorej = environmental performance score for building product alternative];
p = number of environmental impact categories;
IAScorejk = characterized, normalized and weighted score for alternative j with
respect to environmental impact k:
IA, *IVwtk
IAScorelk = — 3- - -*100, where
Normk
IVwtk = impact category importance weight for impact k;
Normk = normalization value for impact k (see section 2.1.3.3);
IAjk = characterized score for alternative j with respect to impact k:
n
IAjk = Lj * lAfacton , where
n = number of inventory flows in impact category k;
lij = inventory flow quantity for alternative j with respect to inventory
flow i, from BEES environmental performance data file (See section 4.4.);
lAfactor; = impact assessment characterization factor for inventory flow i
The BEES life-cycle stage scores, LCScoreSJ, which are displayed on the environmental
performance by life-cycle stage graph, are derived as follows:
n
LCScoreSJ = ^IAScorejk *IPercent1J * LCPercentslJ , where
1=1
LCScoresj = life cycle stage score for alternative j with respect to stage s;
L * lAfactor
IPercentjj =
*IAfactor
LCPercentslJ = r S1J , where
s=l
Isij = inventory flow quantity for alternative j with respect to flow i for life
cycle stage s;
r = number of life cycle stages
295
-------
A.2 Economic Performance
BEES measures economic performance by computing the product life-cycle cost as follows:
t t , where
"
LCC = T C
LCQ = total life-cycle cost in present value dollars for alternative j ;
Ct = sum of all relevant costs, less any positive cash flows, occurring in year t;
N = number of years in the study period;
d = discount rate used to adjust cash flows to present value
A.3 Overall Performance
The overall performance scores are derived as follows:
Score j =
EnvScore, LCC,
(EnvWt * !—) + (EconWt * >—)
*1 oo, where
Scorej = overall performance score for alternative];
EnvWt, EconWt = environmental and economic performance weights, respectively
(EnvWt + EconWt = 1);
n = number of alternatives;
EnvScorej = (see section A.I);
LCQ = (see section A.2)
296
-------
Appendix B. Interpreting BEES Environmental Performance Scores: A Primer
Product ABC has a BEES Environmental Performance Score of 0.0230 and Product XYZ a score of 0.0640.
What does that mean?
Let's start from the beginning, considering just one product and one environmental impact at a time. Let's take a look, say, at the
Global Warming performance of Product ABC, and ask:
Q. How much does Product ABC contribute to Global Warming over its life cycle?
A. BEES tells me that Product ABC contributes 1,279,132 grams of carbon dioxide and other greenhouse gases over its life cycle.
Q. So what? All products contribute greenhouse gases over their life cycle. Is 1,279,132 grams a lot or a little? How can I make sense
of this number?
A. By relating the number to the total amount of greenhouse gases released every year, per person, in the United States. Let's make
this person—John Q. Public—our yardstick, and mark the spot showing Product ABC's greenhouse gases relative to his.
297
-------
30,000,000
25,000,000
| 20,000,000
o
15,000,000
John Q. Public
10,000,000
5,000
Global Warming
Environmental Impact
Q. Okay. Let's say you do that for Product ABC for all 12 environmental impacts. But then what? How can you combine all 12
yardsticks when they 're measuring different things? Wouldn 'tyou be mixing apples and oranges?
298
-------
A. Yes, you would be, unless you made a single, common yardstick for all impacts—one based on Product ABC's percentage share
of John Q. Public's impacts. That way, you could plot all impacts on the same graph. It's like a nutrition label, but instead of reporting
a product's percentages of recommended daily allowances, we're reporting its percentages of John Q. Public's environmental impacts.
Let's do this for Product ABC and Product XYZ.
Share of Annual Per
Capita Impact
DAcidification
n Criteria Air Pollutants
• Ecological Toxicity
• Eutrophication
n Fossil Fuel Depletion
• Global Warming
n Habitat Alteration
• Human Health
n Indoor Air Quality
nOzone Depletion
nSmog
n Water Intake
loon
60% •-
*)%
.20% ._
~^-
01
m
B
— >
OO
10
c&
CO
<^4
>
i
Mi
^
"""1
w
0
z
rr>
Q
m
<4*
•>
"••
I—
0
o
13
S
*<
John 0. Public
Enui ronmertal hipact
299
-------
Share of Annual Pei
Capita Impact
aAcidification
a Criteria Air Pollutants
• Ecological Toxicily
• Eutrophi cation
DFossil Fuel Depletion
• Global Warming
O Habitat Alteration
• Human Health
a Indoor Air Quality
aOzone Depletion
laSmog
DWater Intake
IMrt -, i—,
Ernjror*n*nl»i impact
confused. It looks like Product ABC scores better on Global Warming, but worse on Human Health, than Product XYZ.
How do I know which product is environmentally preferred, all things considered? Can't you just give me a simple average score?
A. I could, but that would mean all environmental impacts are of the same importance. Most experts say that's not the case, so I'll
give you a weighted average score instead, using weights from U.S. EPA experts. Then you can compare Product ABC side-by-side
with Product XYZ when you're shopping for "green" products. But always remember, it's better to have a lower BEES Environmental
Performance Score. Think of the BEES Score as a penalty score—the higher it is, the worse it is.
300
-------
0 Acidification
n Criteria Air Pollutants
• Ecological Toxicity
• Eutraphi cation
n Fossil Fuel Depletion
• Global Warming
n Habitat Alteration
• Human Health
n Indoor Air Quality
n Ozone Depletion
nSmog
0 Water Intake
Environmental Performance
Product ABC
Note: Lower values are foettei
Product XYZ
Alternatives
John Q. Public
301
-------
Q. Okay. But after all this, when I tell my colleagues that Product ABC, with a BEES Environmental Performance Score of 0.0230, is
greener than Product XYZ, with a score of 0.0640, what am I really saying?
A. You're saying that, over its life cycle, one unit of Product ABC does less damage to the environment than does one unit of Product
XYZ. If your colleague's eyes start to glaze over, quickly finish by saying that products with lower BEES scores are greener.
Otherwise, explain that Product ABC is greener because it contributes, on average, 0.0230 % of annual per capita U.S. environmental
impacts, while Product XYZ contributes a larger share, 0.0640 %.
302
-------
References
American Institute of Architects, Environmental Resource Guide, 1996.
ASTM International, Standard Classification for Building Elements and Related Sitework—
UNIFORMATII, ASTM Designation E1557-05, West Conshohocken, PA, 2005.
ASTM International, Standard Practice for Applying the Analytic Hierarchy Process to
Multiattribute Decision Analysis of Investments Related to Buildings and Building Systems,
ASTM Designation El765-02, West Conshohocken, PA, 2002.
ASTM International, Standard Practice for Measuring Life-Cycle Costs of Buildings and
Building Systems, ASTM Designation E917-05, West Conshohocken, PA, 2005.
Ash, Knoblock, and Peters, Energy Analysis of Energy from the Forest Options, ENFOR Project
P-59, 1990.
Bare, J.C., Norris, G.A., Pennington, D.W. andMcKone, T., "TRACI: The Tool for the
Reduction and Assessment of Chemical and other environmental Impacts," Journal of Industrial
Ecology, Vol. 6, No. 3-4, 2003.
Braunschweig, Ahbe S., and Muller-Wenk, R., Methodik fur Oekobilanzen auf der bases
Okologischer Optimierung, Schriftenreihn Umwelt 133, Swiss Federal Office of Environment,
Forests, and Landscape, October 1990.
Bundesamt fur Umweltschutz, Oekobilanzen von Packstoffen, Schriftenreihe Umweltschutz 24,
Bern, Switzerland, 1984.
BUWAL, Methode der okologischen, Knappheit - Okofaktoren 1997, Schriftenreihe Umwelt
Nr.297, OBU/BUWAL, Bern, Switzerland, 1998
Carter, William P., "Development of Ozone Reactivity Scales for Volatile Organic Compounds",
Journal of the Air & Waste Management Association, Vol. 44, July 1994, pp. 881-899
CML, Environmental Life Cycle Assessment of Products: Background, Leiden, The Netherlands,
October 1992.
Curran, M.A. et al., BEES 2.0, Building for Environmental and Economic Sustainability: Peer
Review Report, NISTIR 6865, National Institute of Standards and Technology, Washington, DC,
2002.
Energy Information Administration, Short-Term Energy Outlook—November 2006, U.S.
Department of Energy, Washington, DC, 2006.
303
-------
Forintek Canada Corporation, Building Materials in the Context of Sustainable Development -
Raw Material Balances, Energy Profiles and Environmental Unit Factor Estimates for
Structural Wood Products, March 1993.
Frischknecht, R. et al., "Swiss Ecological Scarcity Method: The New Version 2006," Berne,
Switzerland, 2006.
Goedkoop, M. and Spriensma, R., The Eco-indicator '99: A damage oriented method for Life
Cycle Impact Assessment, VROM Zoetermeer, Nr. 1999/36A/B, 2nd edition, April 2000.
Guinee et al., LCA -An operational guide to the ISO-standards, CML, Leiden, The Netherlands,
2001.
Habersatter K., Ecobalance of Packaging Materials - State of 1990, Swiss Federal Office of
Environment, Forests, and Landscape, Bern, Switzerland, February 1991.
Hofstetter, P. et al., User Preferences for Life-Cycle Decision Support Tools: Evaluation of a
Survey of BEES Users, NISTIR 6874, National Institute of Standards and Technology,
Washington, DC, July 2002.
Intergovernmental Panel on Climate Change (IPCQ, Climate Change 2001: IPCC Third
Assessment Report, 2001.
International Organization for Standardization (ISO), Environmental Management—Life-Cycle
Assessment—Principles and Framework, International Standard 14040, 2006.
Johnson, B.N., "Inventory of Land Management Inputs for Producing Absorbent Fiber for
Diapers: A Comparison of Cotton and Softwood Land Management," Forest Products Journal,
Vol. 44, No. 6, 1994.
Konopacki and Akbari, Simulated Impact of Roof Surface Solar Absorptance, Attic, and Duct
Insulation on Cooling and Heating Energy Use in Single-Family New Residential Buildings,
LBNL-41834, Lawrence Berkeley National Laboratory, Berkeley, CA, 1998.
Levin, Hal, "Best Sustainable Indoor Air Quality Practices in Commercial Buildings," Third
International Green Building Conference and Exposition—1996, NIST Special Publication 908,
Gaithersburg, MD, November 1996, p 148.
Life-Cycle Assessment of Flooring Materials, Jonsson Asa, Anne-Marie Tillman, & Torbjorn
Svensson, Chalmers University of Technology, Sweden, 1995.
Parker et al., "Measured and Simulated Performance of Reflective Roofing Systems in
Residential Building," ASHRAE Transactions, SF-98-6-2, Vol. 104, 1998, p. 1.
Petersen, Stephen R., Economics and Energy Conservation in the Design of New Single-Family
Housing, NBSIR 81-2380, National Bureau of Standards, Washington, D.C., 1981.
304
-------
Portland Cement Association, Concrete Products Life Cycle Inventory (LCI) Data Set for
Incorporation into the NIST BEES Model, PC A R&D Serial No. 2168, PC A Project 94-04a,
prepared by Michael Nisbet, JAN Consultants, 1998.
Potting, Jose and Blok, Kornelis, "Life-cycle Assessment of Four Types of Floor Covering,"
Journal of Cleaner Production, Vol. 3, No. 4, 1995, pp. 201-213.
Potting, Jose and Kornelis, Blok, Life-cycle Assessment of Four Types of Floor Covering,
Utrecht University, The Netherlands, 1994.
PricewaterhouseCoopers (PwC), DEAM: Data for Environmental Analysis and Management,
developed by Ecobilan (a member company of PwC), 2001.
R.S. Means Company, Inc., 2007 Building Construction Cost Data, Kingston, MA, 2006.
Research Triangle Institute. A Multimedia Waste Reduction Management System for the State of
North Carolina, Final Report. Prepared for the North Carolina Department of Health,
Environment, and Natural Resources, Pollution Prevention Program, April, 1993.
Roodman, D.M., and Lenssen, N., A Building Revolution: How Ecology and Health Concerns
are Transforming Construction, Worldwatch Paper 124, Worldwatch Institute, Washington, DC,
March 1995.
Rushing, A.S. and Fuller, S.K., Energy Price Indices and Discount Factors for Life-Cycle Cost
Analysis -April 2006, NISTIR 85-3273-21, National Institute of Standards and Technology,
Washington, DC, 2006.
Saaty, Thomas L., MultiCriteria Decision Making: The Analytic Hierarchy Process—Planning,
Priority Setting, Resource Allocation, University of Pittsburgh, 1988.
SET AC, A Conceptual Framework for Life Cycle Impact Assessment, J. Fava, et al. (eds), 1993.
SET AC, Guidelines for Life Cycle Assessment: A "Code of Practice, " F. Consoli, et al. (eds),
1993.
SETAC-Europe, Life Cycle Assessment, B. DeSmet, et al. (eds), 1992.
SETAC, Life-Cycle Impact Assessment: The State-of-the-Art, J. Owens, et al. (eds), 1997.
Sheehan, J. et al., Life Cycle Inventory of Biodiesel and Petroleum Diesel for Use in an Urban
Bus, NREL/SR-5 80-24089, prepared for USD A and U.S DOE, May 1998.
Spelter H, Wang R, and Ince P, Economic Feasibility of Products from Inland West Small-
Diameter Timber, United States Department of Agriculture, Forest Service ( May 1996).
305
-------
Steen B., A Systematic Approach to Environmental Priority Strategies in Product Development
(EPS). Version 2000, CPM Report 1999:4 and 5, CPM, Chalmers University, Goteborg 1999.
Swiss Federal Office of Environment, Forests and Landscape, Environmental Series No. 250.
United Nations Environment Programme, "Sustainable Building and Construction: Facts and
Figures," Industry and Environment: Sustainable Building and Construction, Vol. 26, No. 2-3,
April-September 2003.
U.S. Department of Agriculture, Office of the Chief Economist, Office of Energy Policy and
New Uses, "Guidelines for Designating Biobased Products for Federal Procurement," Federal
Register, 1 CFR Part 2902, Vol. 70, No. 7, January 11, 2005.
U.S. Department of Energy, National Renewable Energy Laboratory, U.S. Life-Cycle Inventory
Database, http://www.nrel.gov/lci/.
U.S. Department of Labor, Consumer Price Index: All Urban Consumers, Series
CUUROOOOSAH, Bureau of Labor Statistics, http://data.bls.gov, January 3, 2007.
U.S. Department of the Interior, Bureau of Mines, Mineral Commodity Summary, 1994.
U.S. Environmental Protection Agency. Chemical Hazard Evaluation for Management
Strategies, A Method for Ranking and Scoring Chemicals by Potential Human Health and
Environmental Impacts, EPA/600/R-94/177, Office of Research and Development, Washington,
DC., 1994.
U.S. Environmental Protection Agency. Clearinghouse for Inventories and Emission Factors,
Version 6.0, EPA 454/C-98-005, Emission Factor and Inventory Group, October 1998.
U.S. Environmental Protection Agency, Framework for Responsible Environmental
Decisionmaking (FRED): Using Life Cycle Assessment to Evaluate Preferability of Products, by
Science Applications International Corporation, Research Triangle Institute, and EcoSense, Inc,
EPA 600/R-00/095, 2000.
U.S. Environmental Protection Agency, Office of Research and Development, Life Cycle
Assessment: Inventory Guidelines and Principles, EPA/600/R-92/245, February 1993.
U.S. Environmental Protection Agency, Science Advisory Board, Toward Integrated
Environmental Decision-Making, EPA-SAB-EC-00-011, Washington, D.C., August 2000
U.S. Environmental Protection Agency, Science Advisory Board, Reducing Risk: Setting
Priorities and Strategies for Environmental Protection, SAB-EC-90-021, Washington, D.C.,
September 1990.
U.S. Environmental Protection Agency. Technical Background Document to Support
Rulemaking Pursuant to the Clean Air Act - Section 112(g), Ranking of Pollutants with Respect
306
-------
to Hazard to Human Health. EPA-450/3-92-010, Office of Air Quality Planning and Standards,
Research Triangle Park, NC, 1994.
U.S. Environmental Protection Agency, Tool for the Reduction and Assessment of Chemical and
Other Environmental Impacts (TRACl): User's Guide and System Documentation., EPA/600/R-
02/052, U.S. EPA Office of Research and Development, Cincinnati, OH, August 2002.
U.S. Environmental Protection Agency. Waste Minimization Prioritization Tool. Beta Test
Version 1.0. User's Guide and System Documentation, EPA 530-R-97-019, Draft, Office of
Solid Waste, Office of Pollution Prevention and Toxics, Washington, DC, 1997.
U.S. Office of Management and Budget Circular A-94, Guidelines and Discount Rates for
Benefit-Cost Analysis of Federal Programs., Washington, DC, October 27, 1992.
U.S. Office of Management and Budget Circular A-94, Guidelines and Discount Rates for
Benefit-Cost Analysis of Federal Programs: Appendix C, Washington, DC, January 2007.
Whitestone Research, The Whitestone Building Maintenance and Repair Cost Reference 2006-
2007, 11th Annual Edition, Santa Barbara, CA, 2006.
Wilson, Alex and Malin, Nadav, "The IAQ Challenge: Protecting the Indoor Environment,"
Environmental Building News, Vol. 5, No. 3, May/June 1996, p 15.
Wilson, Alex, "Insulation Materials: Environmental Comparisons," Environmental Building
News, Vol. 4, No. 1, January/February 1995, pp. 15-16
World Meteorological Organization (WMO), Scientific assessment of ozone depletion, 1991.
World Meteorological Organization (WMO), Scientific Assessment of Ozone Depletion: 1998,
Report 44 (Global Ozone Research and Monitoring Project).
307
------- |