THE
GREENING
CURVE
Lessons Learned in the Design of the
New EPA Campus in North Carolina
i. Environmental Protection Agency
EPA 220/K-02-001
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THE
GREENING
CURVE
Lessons Learned in the Design of the
New EPA Campus in North Carolina
November 2001
I
ACKNOWLE
MENTS
Sandra Mendler, of Hellmuth, Obata and Kassabaum, was the
principal author of the Greening Curve. Contributors and reviewers
included Wanda Allen, Tom Ashmore, Allen Atkins, Bob Barr, Jim
Doussard, Bill Gaines, Jamie Gagliarducci, Sandy Germann, Bucky Green,
Judy Kincaid, Bill Laxton, Sandra Leibowitz, Fred Livingston, Chris Long,
Gail Lindsey, Nadav Malin, Lisa McCabe, Billy Morris, Michael Overcash,
Robert Payne, Suzanne Roberts, Peter Schubert, Rhonda Sherman,
Donna Stankus, James White, Gail Whitfield, Joyce Yin and many others.
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iLE OF
TENTS
Introduction
Project Summary 11
The Process
The Importance of Common Sense
The Result
Lessons Learned 13
Background 15
Sustainability 16
What is Sustainable Development?
Green Buildings
Sustainable Design Resources
Sustainable Design for Federal Facilities
Resource Conservation
Pollution Prevention
Ecosystems Protection
Indoor Environmental Quality
Design Process Discussion
The Right Start
Making the Commitment
Defining the Challenge
Prioritizing Environmental Goals
Embedding Green Goals in Conceptual Design
Seizing Early Opportunities
Design Optimization: A Cyclical Process
Evaluating Criteria/Revising Assumptions
Identifying Performance Benchmarks
Using Models and Evaluation Tools
Researching Environmental Impact
Greening the Team
Environmental Champions on the Team
Local Sustainability Network
Integrated Team Approach
Maintaining the Commitment
Following Through on the Details
Tracking Environmental Performance
Using Green Value Engineering
Preparing for Construction
Conclusion
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Design Issues Discussion
Site Design
Minimize Site Disruption
Structured Parking
Fire Lanes
Erosion Control
Loop Road
Preservation and Enhancement of Wetland Areas
Specimen Tree Study
Water Quality
Pollution Prevention Strategies
Erosion Control
Water Pretreatment Options
Landscaping
Low-Maintenance Landscaping
Grasses and Wildflowers
Wetland Plantings
Composting
Building Envelope
Evaluation of Building Loads
Sun Control
Glass Selection
Thermally Broken Windows
Light Shelves
Insulation
Infiltration
Albedo Control
Operable Windows
Space Planning
Modular Office Design
Modular Lab Design
Building Atrium
Building Massing
Energy and Daylighting Analysis
Atrium Skylight Options
Lighting Systems
Green Lights
Daylighting
Task Lighting
Laboratory Lighting
Office Lighting
Special Spaces
Lighting Controls
Exit Signs
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Building Mechanical Systems
Energy Modeling
Central Utility Plant
High Efficiency Chillers and Boilers
Variable Air Volume
Outside Air Economizer Cycle
Variable Frequency Drives
High Efficiency Motors and Fans
Heat Reclamation for Hot Water Generation
Laboratory Fume Hoods
Heat Recovery for Laboratory Exhaust
CFC Free Refrigeration Equipment
Building Humidification
Central Direct Digital Control (DDC) System
Building Commissioning
Building Acceptance Test Manual
Summary of HVAC Systems
Water Conservation
Water Conserving Fixtures
Water Efficient Cooling Towers
Ozone Treatment for Cooling Towers
Alternative Technologies
Photovoltaics
Fuel Cells
Wind Power
Solar Hot Water
Central Hot Water vs. Point-of-Use Hot Water
Grey Water Reuse
Rain Water Catchment
Building Materials
Life Cycle of Materials and Products
Durable Materials
Recycled Content
Local Materials
Low Toxic and LowVOC Materials
Sustainably Harvested Wood
Resource Recovery
Site Materials
Government Procurement Requirements
Indoor Air Quality
Source Control, Source Isolation and Source Dilution
Designing for Indoor Air Quality
IAQ Facilities Operation Manual
Indoor Air Quality vs. Energy Efficiency
Low-Emission Materials
IAQ Testing of Materials
Construction Procedures
Risk Prevention
Electromagnetic Fields
Radon Gas
Waste Management
Efficient Building Design
Waste Reduction
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Increased Building Longevity
Building Adaptability
Collection and Handling of Recyclables
Recycling Chutes
Reuse of On-Site Materials
Construction Waste Recycling
Gypsum Grinding
Construction
Partnering for Construction
Plant Rescue
Reuse of Land Clearing Debris
Rock Crushing
On-Site Concrete Batch Plant
RotoReclaimer
Salvage of Demolition Materials for Reuse
Construction Waste Recycling
Use of Recycled Content Building Materials
Submittals Review During Construction
Constant Vigilance
Endnotes
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
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INTRODUCTION
The Greening Curve
Buildings have an enormous impact on the environment. Consuming hundreds of
tons of building materials, drawing billions of watts of electricity and burning
countless barrels of fuel during each their lifetimes, every home, school, hospital,
factory, lab or office that we build will gobble up natural resources and effect
pollution for many decades. So when the U.S. Environmental Protection Agency
started planning the largest facility in its history, environmental impacts were key
considerations.The Agency faced a haunting question-how could EPA build more
than one million square feet of labs and offices on a wooded, 132-acre site without
making sustainability a key consideration?
The answer was easy. As one of the leading environmental organizations in the
world, EPA had to lead by example. But what did this mean in practice? What,
exactly, should be done to build a "green" building? On a government project with
an average budget, how could EPA pay the price to build a campus that would serve
as a model for environmental stewardship? Finding the answers would prove to be
quite a challenge, especially since few people believed it was possible to be
ecologically smart without being economically foolish.
As EPA began designing this new campus, a revolution was quietly stirring.
Designers and builders around the globe were starting to work together to
define sustainable building practices. As success stories were shared and new
ideas caught on, the green building movement began to emerge.
As the national and international design and construction communities worked
diligently to address the issue of sustainability, so did the team that designed
the EPA campus.The steep learning curve for green buildings presented
countless questions, yet offered few easy answers. Nonetheless, a growing
number of architects, engineers, builders and facility owners sought to define
for themselves what was needed to build high-performance buildings in
environmentally-responsible ways.The project team for the new EPA Campus
at Research Triangle Park immersed itself in this dialogue-actively participating
and helping to shape many of the discussions.
Thus, the parallel paths met.The new EPA campus took root as sustainable
buildings began to grow in number and significance. "The Greening Curve"
shares lessons from this common journey in the hope that others will be able
to create even better, more environmentally-sound buildings in the future.
EPA Campus Milestones
7984-7997
7992-7995
7996-7997
7997-2007
Planning
Design
Procurement
Construction
Introduction
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Sustainable Building Milestones
7987 "Sustainability" defined by the World Commission on
Environment and Development.
7990 American Institute of Architects (AIA) Committee on the
Environment established.
7992 Green Building Case Studies start to emerge-Audubon
House (New York City), Natural Resources Building
(Olympia, Washington) and others.
Environmental Resources Guide funded by EPA and
published by AIA.
Energy Policy Act passed in the United States
7993 U.S. Green Building Council (USGBC) established.
Early Green Building Assessment Tools unveiled in Canada
(BEPAC) and Great Britain (BREEAM).
Federal Executive Orders issued on acquisition, recycling,
waste prevention and ozone-depleting substances. Other
Executive Orders followed through the year 2000, covering
energy and water conservation and environmental
management.
7995 Federal Guidelines for Buying Recycled issued by EPA
(Recovered Materials Advisory Notice).
7996 Sustainable Building Technical Manual published by EPA, U.S.
Department of Energy, USGBC and Public Technology, Inc.
7997 Green Developments case studies published by Rocky
Mountain Institute.
7998 First U.S. Green Building Assessment Tool released by
USGBC as Leadership in Energy and Environmental Design
(LEED).
First International Green Building Assessment Tool created
and tested through the Green Building Challenge (GBC)
conference in Canada.
Green Building Advisor guidelines and case studies issued by
the Center for Renewable Energy and Sustainable
Technology.
BEES Life Cycle Materials Database first released by the
National Institute of Standards and Technology (Building for
Environmental and Economic Sustainability-BEES).
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
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Learning Together
The team that created the new EPA campus involved itself in the development of
several of these nationally recognized sustainable building tools-such as LEED, the
Green Building Challenge, the Environmental Resource Guide, BEES and the Green
Building Advisor. Locally, the team also helped craft the Triangle J Regional High
Performance Building Guidelines, as well as the "WasteSpec" construction recycling
specification which has now become a national reference.
By joining forces with others who were eager to make better buildings, and by
tapping EPA's own in-house environmental experts, the design team was able
to enhance the quality of the new campus while advancing the broader
dialogue on sustainability.
The Team
EPA proved that a state-of-the-art laboratory and office complex can be a
model for environmental stewardship without costing extra.The key to this
success was a dynamic, creative team approach that involved a radical shift in
culture. From day one, the environment was placed on equal footing with cost
and performance-a new mindset that helped guide every major decision and
ultimately created a model for sustainable facilities.
Key members of the project team are as follows:
U.S. Environmental Protection Agency
As the owner, EPA was a hands-on, active participant in the project. In
addition to full-time project managers and engineers, EPA brought
researchers and regulatory program experts in as advisors on
environmental issues.
U.S. General Services Administration
GSA served as a technical consultant during design and managed the
construction phase of the new EPA campus.
Introduction
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U.S. Army Corps of Engineers
The Army Corps of Engineers was the primary design consultant to
EPA and GSA throughout design and construction.
National Institute of Environmental Health Sciences
EPA's neighbor and partner on the federal site, NIEHS operates
central campus utility services and shares responsibility for the
on-site child care center.
Designers-HOK
Hellmuth, Obata + Kassabaum (HOK) Inc. was the lead design firm,
and their newly-formed national "Green Team" leader became an
integral member of the EPA project team. Major consultants included
Roberts/Stacy Group (associated architect), R.G.Vanderweil, Inc.
(mechanical/electrical), Greenhorne and O'Mara, Inc. (civil), Weidlinger
Associates (structural), GPR Planners (lab design), and Cortell
Associates (environmental).
Construction Manager-Gilbane
As a consultant to GSA, Gilbane Building Company provided
construction administration and quality assurance services.
Construction Contractor-Clark
Clark Construction Group built the 1.1 million square foot main
facility and campus infrastructure.
Design-Build Contractor-Beers
During the construction of the main facility, Beers Construction
Company updated and redesigned EPA's National Computer Center
and built this separate, 100,000 square foot building on the campus.
The Green Bottom Line
Here's what the team has delivered-a 100-year building, 40% energy savings,
80% construction waste recovery, 100% stormwater treatment through native
plants and wetlands on site, soothing daylight in offices, clean indoor air,
flexible labs and more-all with no extra budget for building "green."
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina 10
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Project Name
US EPA Campus
Location
Research Triangle Park,
North Carolina
Completion Date
Year 2001
Square Footage
Total gross area: 1,160,000
Net program area: 625,000
Laboratory space: 270,000
Office space: 220,000
Computer center: 70,000
Building common: 50,000
« Child care center: 15,000
Examples of Materials Used
4 acres of concrete block walls
35 acres of drywall
7 acres of carpet
12 acres of ceiling tile
2,861 interior doors
19.6 miles of telcom conduit
Accomplishments
Site Design
Building fits within contours of
site, reducing need to regrade
and limiting disruption to habitats
and wetlands. Natural woodlands
and wildflower plantings minimize
water, fertilizer and pesticide use,
and reduce associated
maintenance costs.
Water Quality
Stormwater runoff is treated
naturally using bio-retention, an
innovative system that uses soil
and plants to remove
contaminants from Stormwater.
Reductions in impervious surface
for roadways and parking.
increase green space.
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PROJECT
SUMMARY
The new EPA Campus at Research Triangle Park, North Carolina is home to
one of the world's largest groups of scientists, engineers, policy makers and
administrators dedicated to understanding and solving environmental problems.
With hundreds of environmentally-friendly features, it's also a model "green
building" and proof that environmental protection can be accomplished
without raising costs.
The new campus is the largest construction project in EPA's history, and from the
start, EPA recognized it had a once-in-a-lifetime opportunity to lead by example.
EPA chose to build a home that strongly reflected the missions to be carried out
within its walls. While providing the Agency with flexible, state-of-the-art
laboratories and offices, the new campus also embodies a solid environmental
ethic in every aspect of design, construction and operation.
The 1.2 million square foot facility is located on a 133-acre site, part of a 511-acre
federal campus dedicated to environmental and public health research. It
accommodates more than 2,000 people and contains 600 laboratory modules in five
laboratory wings, three office wings and a six-story office tower with a cafeteria and
conference center. The buildings are organized along a series of atria that act together
as a "main street" to enhance communication among professional staff. Laboratory
types include chemistry and biology labs, materials testing labs, electronics labs,
automobile testing facilities, and large-scale combustion research labs.
The Process
From the beginning, the core design group focused on defining environmental
objectives and tracking progress toward meeting them. Work sessions included
participation by green advocates, architects, engineers and building users including
researchers and administrative officers. One of the most valuable benefits of the
process was the discussion between technical and non-technical people. Innovative
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solutions emerged from systematically
reviewing multiple options, and making
comparisons with a variety of functional
and environmental benchmarks. The
environmental soundness of decisions
was tested in every phase of design.
The Importance of
Common Sense
Raising questions every step of the way,
design team members maintained a
focus on their specialties while
collaborating across disciplines to
identify creative, practical solutions. By
stepping back and viewing the whole
through the lens of environmental
stewardship, large, seemingly obvious
issues were uncovered that might
otherwise have been overlooked.
For example:
Why install non-native turf grass that
requires ongoing maintenance and will use 250,000 gallons of water per month in the
summer, when we can use wildflowers, native grasses and native woodland plantings
that will be more appropriate to the natural site environment and require little care?
Why would water quality ponds that were intended to serve as a passive "natural"
technology require the destruction of acres of forestland? Wasn't there a solution that
would be less disruptive to the site?
How can we install over seven acres of carpeting into a facility without understanding
how the choice of carpeting affects the longevity of the carpet, how maintenance
impacts indoor air quality and what the recyclability is at the end of its useful life?
The Result
The facility limits environmental
impact throughout all aspects of its
design, construction and operation.
Within a fixed budget, the project
team was able to meet all functional
requirements, reduce long-term
operating costs and improve
environmental performance. The
result is a campus that reflects the values
of EPA through its stewardship of
natural resources while simultaneously
demonstrating the added value that can
be realized from a sustainable approach
to design and construction.
Energy Conservation
Compared with standard new
lab/office construction, the EPA
Campus uses 40% less energy
for a projected savings of more
than one million dollars per
year-conserving non-renewable
fossil fuels and reducing air
emissions.
Lighting
Daylighting, high-efficiency lamps
and ballasts, task lighting, and
smart controls yield savings in
electrical energy use and
improve lighting quality.
Building Materials
Building materials selected to be
durable and low maintenance,
and to minimize life-cycle
environmental impact.
Specifications ensure
compliance with environmental
requirements, such as recycled
content, sustainably-harvested
wood and chemical content
limits.
Indoor Air Quality (IAQ)
Improved ventilation criteria,
special construction
requirements and careful
selection of materials and
finishes promote superior IAQ.
A comprehensive IAQ Facility
Operations Manual was
produced to guide future
operations and maintenance.
Waste Recycling
Design accommodates recycling
during occupancy. 80% of all
construction waste recycled for
a diversion of about 10,000 tons
of material from local landfills.
Design flexibility conserves
resources by minimizing impact
of future changes.
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
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LEARNE
Green Design Is Better Design
In addition to being environmentally responsible, the green design strategies
employed for the EPA Campus project provided equal or better performance in
terms of comfort, durability and ease of maintenance. Benefits for occupants
include greater access to daylight, more fresh air, protected forest and wetland
areas and a design that feels more connected to nature.
Green Design Is Affordable
Energy and water conservation, low-impact site design, materials minimization
and other choices have clear economic benefits. Green design features with little
financial payback can be afforded by making trade-offs in other areas of a project.
Balance tough choices with easy wins.
Make the Commitment
Project leaders must make clear, consistent, and unambiguous statements about
their commitment to design and build a green building. An owner can underscore
their commitment to green design by including environmental design requirements
in the design contract.
Focus on the Process
The state-of-the-art for green design is evolving rapidly, and the best green design
solutions are highly responsive to their site and the unique requirements of their
building type. Focus on the design process to achieve your goals.
Seek out Green Partners
There is a growing community of architects, engineers and builders that are
dedicated to developing green buildings. Begin with committed partners that share
your vision and enjoy the challenge of green design.
Recruit Environmental Champions
To maintain a focus on green design goals, owners, designers and builders need to
identify green champions to lead within their ranks. Green advocates on the team
can perform ongoing design reviews and promote multi-disciplinary collaboration
to achieve the best solutions.
Identify Performance Benchmarks
Benchmarks put performance data in perspective. Seek out benchmark
information that will allow the team to understand "typical" performance as well
as the potential for "improved" green building performance.
Tap Into the Sustainability Network
Awareness and knowledge of green design is growing rapidly, and many are eager
to share their knowledge in the interest of protecting the environment. Discover
extensive resources on the internet and in print, and place a priority on local
resources. Talk to others who have been through a green building process, and visit
their facilities.
1 *J Lessons Learned
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Reconsider Assumptions
Design criteria drive performance. Great savings can come from challenging
criteria that may no longer be valid. Encourage the team to raise questions and
re-evaluate assumptions.
Make Time for Research
Even though more and more resources are being created to help design teams
understand environmental impacts, innovative design solutions will require
research to identify the best solutions. Don't rush the process unnecessarily.
Use Models and Evaluation Tools
Energy and daylighting models can help the team make choices that reduce first costs
and save energy throughout the life of the project. Green building evaluation tools
can bring a comprehensive sustainability focus to the design process, and can help
assess actual results for whole buildings and sites. Make a commitment to use energy
and daylight modeling and evaluation tools creatively to improve design performance.
Seize Early Opportunities
Make an effort to integrate green design strategies in the early phases of design.
While it is never too late to make a better choice, the cost of shifting to greener
design alternatives will increase over time.
Use Green Value Engineering
Often seen as a threat to green design because of its focus on immediate savings,
value engineering (VE) can be used as a tool for improving environmental
performance. To ensure a balanced focus on cost, function and the environment,
assign green advocates as full-time participants in the VE process.
Prepare for Construction
Take time to explain green design goals to the construction team. Because green
design strategies are still new to many contractors, sessions to educate both
management and the workers can be extremely valuable. Establish the
environment as a project goal on equal footing with traditional construction goals
of safety, quality, budget and schedule.
Follow Through During Construction
Pay close attention throughout the construction process, with a keen eye toward
specification compliance and substitutions.
Keep Talking
Make sure that environmental considerations are part of key conversations. It takes
constant reinforcement to maintain the focus.
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina 14
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BACKGROUND
In 1968, the Research Triangle Foundation deeded land to the federal government
for a "U.S. Public Health Service Research Park," setting aside 511 acres for
federal environmental research facilities. The National Institute of Environmental
Health Sciences (NIEHS) was the first to locate there in 1980. The National
Center for Air Pollution Control, later to become EPA, had recently moved to
North Carolina from Cincinnati, Ohio. Without funds for a permanent facility,
they set up temporary quarters in leased space in the Raleigh/Durham/Research
Triangle Park (RTF) area. As EPA became established in RTF, it expanded into a
collection of leased buildings which were not ideally suited to its research needs.
This dispersion of staff led to extensive amounts of time spent traveling
between buildings.
Between 1984 and 1991, several studies by EPA and GSA evaluated long-term
housing alternatives for EPA in Research Triangle Park. The studies consistently
found that EPA could not continue to conduct its research programs in the
existing leased facilities, and recommended consolidation into a new government-
owned facility on the federal site. The studies also found that consolidation would
significantly reduce operating costs-saving the government millions of dollars each
year while vastly improving laboratory conditions and employee productivity.
In considering housing alternatives, the government also evaluated the option of
renovating existing buildings to upgrade laboratories and consolidate the
workforce. Although building renovation is often viewed as environmentally
preferable to new construction, this was found to be an impractical alternative.
EPA owned none of its own facilities, and even the largest was only half the size
needed to consolidate operations. Massive investment would have been required to
upgrade structural, mechanical and electrical deficiencies and to meet current code
requirements. In late 1991, the decision was made to build a new campus when
Congress appropriated funds for design.
10 Background
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SUSTAINABILITY
What is Sustainable Development?
Sustainable development was defined by the United Nations World Commission
on Environment and Development in the 1987 Brundtland Report, as "those paths
of social economic and political progress that meet the needs of the present without
compromising the ability of future generations to meet their own needs."1 In 1993,
a year after the Earth Summit in Rio de Janeiro, the World Congress of Architects
similarly defined "sustainability" for the architectural community.
There is general agreement that environmental degradation is accelerating
worldwide, and that projected increases in rates of consumption and population
growth cannot be sustained. Solutions will require widespread efforts to increase
efficiency, reduce pollution and restore ecosystems. With a goal of building in
harmony with the natural environment, sustainable development involves a more
sophisticated understanding of natural systems than is required by conventional
development. Sustainable design solutions also require designers to expand their
awareness of the environmental impact related to industrial processes,
transportation and construction. Because the impact of buildings and construction
on the environment is significant, there is great potential for improving the
environment through better design of buildings. This requires a responsibility to act
differently than we have in the past to reduce traditional environmental impact.
Green Buildings
Roughly one-third of the environmental impact in the U.S. is reported to come
from constructing, operating and demolishing buildings. This impact is a result of
both the direct and indirect consequences of land use, natural resource depletion,
air and water pollution and waste generation.
Green buildings seek to limit adverse impact on the environment and health
throughout their entire life cycles-from the acquisition of materials,
transportation, construction, use and eventual disuse. To accomplish this,
Sustainability means
meeting our needs today
without compromising the
ability of future generations
to meet their own needs.
UIA/AIA World Congress of
Architects, June 1993
Environmental Impact of Buildings
Percentage of U.S. nationwide, annual impact
Energy Use
Atmospheric Emissions
Raw Materials
Solid Waste
Water Use
Water Effluents
Land Use
Other Releases
0%
50%
100%
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
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A Sampling of
Environmental Requirements
Mandated by Executive Orders
EO #12843: Procurement
Requirements and Policies for
Federal Agencies for Ozone-
Depleting Substances, 4/93
Requires minimizing procurement of
ozone-depleting substances per
phaseout schedules outlined in the
Clean Air Act.
EO #12873: Federal Acquisition,
Recycling, and Waste Prevention,
10/93
Requires EPA to publish federal
procurement guidelines for
recommended recovered content
in certain materials.
EO #12902: Energy Efficiency and
Water Conservation at Federal
Facilities, 3/94
Requires federal agencies to implement
conservation strategies in their buildings
as stated in EPACT.
EO #13101:Greening the
Government Through Waste
Prevention, Recycling, and Federal
Acquisition, 9/98
Requires GSA and Department of
Defense to develop sustainable design
and development principals for the siting,
design and construction of new facilities;
requires agencies to design new facilities
based on lowest life-cycle cost.
EO #13123: Greening the
Government Through Efficient
Energy Management, 6/99
Requires government to promote
sustainable building concepts and help
foster markets for emerging sustainable
technologies.
EO #13148: Greening the
Government Through Leadership
in Environmental Management,
4/00
Requires federal agencies to integrate
environmental accountability into daily
decision making and long-term planning
processes across all agency missions,
activities and functions.
designers must view the building holistically and consider environmental impact
related to site development, transportation and infrastructure, as well as the
impact related to the full life-cycle of all building materials and products that
comprise the building.
Green buildings represent important steps in the evolution of buildings and
communities toward sustainability. As such, they consider all opportunities to:
Conserve Resources
Prevent Pollution
Protect Ecosystems
Enhance Indoor Environmental Quality
Sustainable Design Resources
When EPA began planning for its new facility, the concept of "sustainable design"
was just beginning to gain momentum in the U.S. Only a handful of green case
study buildings had been completed, and the information on what to do and how
to do it was scarce. In 1990, shortly after the 20th anniversary of Earth Day, the
American Institute of Architects (AIA) established the Committee on the
Environment (COTE) to begin the process of filling the information void for the
architectural profession. In 1991, EPA entered into an agreement with the AIA to
work together to create a comprehensive environmental design resource guide
entitled the Environmental Resource Guide (ERG). The ERG was first published
in 1992 as an AIA publication, and was subsequently republished by John Wiley &
Sons in an updated format in 1996, followed by annual updates in 1997 and 1998.
Throughout the 1990s, the "green building" movement continued to evolve. In
1993, the U.S. Green Building Council was formed and began work on a green
building rating system for the U.S. In 1996, a comprehensive sustainable design
resource guide entitled the Sustainable Building Technical Manual was published
by Public Technology Inc. with the support of EPA, the Department of Energy
and the U.S. Green Building Council. In 1997, John Wiley & Sons published
Green Developments, a compendium of 100 recently completed green building
case studies written by the Rocky Mountain Institute. Since this time, additional
green design resources have emerged.
Sustainable Design for Federal Facilities
The Energy Policy Act (EPACT) of 1992 was an important milestone in the
sustainable design movement because it signaled the federal government's
recognition of its own leverage, applied through example and through unparalleled
purchasing power. EPACT was signed into law in October 1992, shortly after
design work had begun on the new EPA Campus. It provided guidance to federal
facility planners on how to improve the energy performance of their agencies, and
it set a goal of a 30% reduction in commercial building energy usage by 2005,
based on a 1985 baseline. EPACT required that all government buildings "install
in Federal Buildings owned by the United States all energy and water conservation
measures with payback periods of less than 10 years," and that these conservation
measures be evaluated using a life-cycle costing methodology.
EPACT also mandated that each federal agency that constructs at least five buildings
a year "designate at least one building, at the earliest stage of development, to be a
showcase highlighting advanced technologies and practices for energy efficiency, or
use of solar and other renewable energy." Even though EPACT and the subsequent
Executive Orders (EOs) were enacted after design had already begun on the new
17
Sustainability
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Campus, it provided additional support and validation to project team members
committed to developing the EPA Campus as a showcase facility. In June 1999, the
federal commitment to green buildings remained strong as EO #13123 was issued,
further advancing the government's pledge to green its facilities.
Resource Conservation
Resource use, which includes energy, water and materials, is fundamental to the
impact buildings have on the environment. Non-renewable resources are being
depleted and many renewable resources, such as timber and water, are being
extracted at rates that exceed their ability to be replenished. According to the
WorldWatch Institute, three billion tons of raw materials, approximately 40% of
all materials entering the global economy, are turned into foundations, walls, pipes
and panels for building construction each year.3
Green buildings seek to use environmentally-preferable building materials. This
refers to all of the products and materials that have reduced the environmental
impact over the full life-cycle of the material, as compared to other available
options. Conservation of material resources also depends on efficient use of
materials, enhanced durability and strategies to encourage re-use and recycling of
resources. Green buildings accommodate re-use and recycling so that waste
generated by building occupants can be handled properly. Construction waste,
which constitutes approximately 25% of municipal landfill content, can also be
reduced, re-used and recycled.
Energy conscious design reduces the use of energy resources through
improvements to siting, building envelope design and daylighting with energy-
efficient electric lighting. Required mechanical systems should be optimized to
maximize efficiency, and heat reclaim systems that "recycle" energy for heating,
cooling and/or humidifying the air should be investigated.
Opportunities to
Conserve Resources
Energy Use
Heating and cooling
Air circulation
Lighting
Water heating
Special equipment
Plug loads
Water Use
Landscape irrigation
Plumbing fixtures
Mechanical equipment
Appliances
Building & Site Materials
Raw material acquisition
Production processes
Packaging and shipping
Installation and finishing
Durability
Maintenance
Waste disposal and recycling
U.S. ENERGY USEWITH
AREAS AFFECTED BY ARCHITECTURE
impact of architect's
decisions on transportation
energy use not
related to construction
or operation of buildings
20%
fossil fuel
space heating, cooling
domestic hot water, misc.
11%
electricity for
building operation
electricity for
building construction
3%
fossil fuel for
building construction
Source: NCARB, 7993
NCARB
The National Council of
Architectural Registration Boards
is a non-profit federation of 55
state and territory architectural
registration boards in the
United States.
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
18
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Sources of Pollution
Energy Use
Petroleum extraction and
refinement
Oil spills
Air emissions and nuclear waste
from energy usage
Air pollution from automobiles
and other transportation
Thermal waste
Ozone-depleting substances
Water Use
Contaminated runoff
Waste water
Water treatment by-products
Materials Use
By-products from material
manufacture
Wasteful packaging
Solid and liquid waste
Hazardous waste
Environmental Impact on
Ecosystems
Displacement of habitat for
buildings, roadways and parking
Increase in impervious surface
Reduction in groundwater
recharge
Soil erosion
Contamination of water bodies
Contamination of groundwater
Use of invasive exotic plants
Use of fertilizers and pesticides
Urban heat island effect
Finally, conservation of water resources in green buildings involves strategies to use
less water for HVAC equipment and appliances, flushing fixtures, potable water
uses and irrigation. Water harvesting and water re-use strategies can reduce
demand for potable water supplies.
Pollution Prevention
Buildings and their sites contribute to the creation of waste and pollution as a
result of their use of energy, water and materials. In nature there is no waste
because all by-products of natural processes serve as "food" for other processes.
Many of the industrial processes employed in the creation of buildings, however,
release solid, liquid or gaseous by-products into the environment that serve no
useful purpose and are potentially harmful.
Green building design searches for solutions that prevent the creation of pollution
at the source. By limiting energy and water use, and making efficient use of
environmentally-preferable materials, pollution can be reduced. Integrating
environmentally-sound recycling into design solutions can further reduce pollution.
Waste treatment followed by safe disposal is required for pollution that cannot be
prevented or recycled. On-site, natural treatment options should be considered to
treat waste including bioretention, constructed wetlands and composting.
Ecosystems Protection
The impact of buildings on natural ecosystems occurs on multiple levels, including
loss of open space and habitat, intrusion on fragile ecosystems, alteration of
stormwater flows, erosion and loss of soil resources, contamination of water
resources and use of non-native and invasive species or monocultures of vegetation.
Green buildings seek to develop "low impact" solutions which work in harmony
with natural systems, and minimize disruption to plant and animal habitats.
Redevelopment of previously built sites and compact development can limit
disruption. Native, low maintenance landscapes, reductions in impervious materials
and natural filtration of stormwater can reduce the need for treatment strategies.
Indoor Environmental Quality
In the United States, it has been estimated that people spend more than 90% of
their time indoors.4 This makes the quality of the indoor environment critical.
Indoor environmental quality refers to comfort and building-related health and
productivity issues that result from the quality of interior lighting, acoustics,
thermal control and indoor air quality (IAQ).
Indoor air quality depends upon a variety of factors, including the levels of
particulates, volatile organic compounds (VOCs) and molds, bacteria or other
biological contaminants in the air stream. Indoor air contaminants can come from
building and finish materials, cleaning and maintenance products, mechanical
equipment, microbial growth in wet areas, tobacco smoke, radon gas, office
machines, exterior pollution and a variety of other sources.
EPA rates indoor air pollution among the top five environmental risks to public
health. It has been estimated that unhealthy indoor air is found in up to 30% of
new and renovated buildings. Both the long- and short-term health effects of poor
indoor air are revealing themselves at an increasing rate due to occupant
complaints, while specific IAQ problems are being discovered through testing
and monitoring.
19
Sustainability
-------
Temperature of the indoor environment is also an important factor. American
Society of Heating and Refrigeration and Air Conditioning Engineers stipulates
that the indoor comfort zone is between 68 degrees Fahrenheit and 82 degrees
Fahrenheit, and 20 to 50 percent relative humidity. If people are too hot or too
cold, the discomfort will cause inefficiency in their performance.
Equally as important is lighting. Natural lighting generally improves the
environment, uplifting people and enhancing their productivity. Electrical lighting
should be designed to simulate the effect of natural light.
Acoustics are also a critical factor in the indoor environment. In today's fast-paced
office environment, people need quiet spaces that minimize disruptive noise and
afford a sense of privacy.
Green building design solutions promote healthy environments while also seeking
improved comfort and occupant satisfaction. Recent studies have shown that
buildings with good indoor environmental quality can provide significant financial
benefits. Effective ventilation, natural lighting, indoor air quality and good
acoustics have been shown to significantly increase worker productivity.
Impact on Indoor
Environmental Quality
Site & Landscape
Daylight access
Reflectivity of exterior
materials
Views, connection to nature
Noise
Outdoor air quality
Vehicle exhaust
Radon
Pollen and other allergens
Building & Site Materials
Chemical emissions from
materials, adhesives and finishes
Microbial contamination
Respirable fibrous materials
Building Operations
Ventilation rates
Temperature control
Humidity control
Daylighting
Electric lighting levels
Glare
Acoustics
Chemical emissions from
cleaning materials
Environmental tobacco smoke
Noise
Pest control
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
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Traditional Decision Model
Green Decision Model
DISCUSSION
Green buildings challenge the norms of the design and construction industry.
Design teams must actively search for better alternatives to conventional models to
successfully reduce the environmental impact related to buildings and construction.
This search requires an improved decision model that balances cost, function and the
environment. The result is an approach that expands the traditional "cost-benefit"
decision model to one that includes environmental performance as a core value.
Early on, the design team focused on explicitly defining environmental objectives,
then tracking progress at each stage of design. To support this effort, an open,
collaborative process was established which enhanced dialogue and decision
making. The group found that design innovations led not only to the creation of a
more environmentally sound facility, but to improved quality and lower operating
costs as well.
Even though this green design process required extensive research and
investigation of design alternatives, the group found that the overall design process
gained efficiencies from the use of an inclusive approach. Guided by clear goals
and defined milestones, this approach gave a sharp focus to the design effort,
enabling more to be accomplished within the boundaries of a conventional project
schedule and budget.
The Right Start
At the beginning of every project, there is an opportunity to define goals and
objectives and establish a strategy for meeting them. First and foremost, EPA
made a commitment to design and build a green building. From there, the design
team proceeded to incorporate environmental design goals into each stage of the
planning process.
Making the Commitment
The sheer size of the EPA Campus project-over one million gross square feet of
offices and laboratories-magnified the environmental impact of each design
decision. Understanding that by its very nature, the construction of the new facility
posed a negative impact on the environment, EPA felt a strong responsibility to
explore design options that promised to minimize this environmental burden.
In one of the early design reviews, a proposal was presented to route the road
leading to the new Campus through an area that featured a 100-year-old Oak tree.
The EPA team made a decision to re-route the road rather than sacrifice the tree
even though it did require additional time and money. This decision not only sent
a message to the entire project team underscoring the commitment to the
environment, it represented the reality of moving toward a green facility.
21
Design Process Discussion: The Right Start
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When placed in the context of EPA's organizational mission, this sense of
obligation was further magnified. EPA felt that the design and construction of its
new facility presented not just an opportunity, but also an obligation to lead by
example. As the building owner, EPA would control nearly all design decisions. If
done correctly, the Agency believed that its facility could become a functional
model for the greening of other public and private sector facilities, and help
advance sustainable design and construction as an industry-wide practice.
Defining the Challenge
Before the formal design of the new facility began, EPA set the course for the
project by describing the environmental challenge both for itself and for the
professional design team it would solicit. Green design criteria were written into
the key project documents, including the solicitation for Architect/Engineer (A/E)
services, the Program of Requirements (FOR), and the contract with the chosen
A/E. By clearly and consistently presenting its environmental goals and explicitly
integrating them into the project requirements, EPA set a direction for the design
firms and established a set of procedures for tracking environmental performance
during the design process.
The solicitation for A/E services was EPA's first opportunity to present its vision for
the new facility to potential A/E contractors. Recognizing the importance of
choosing a partner that would share EPA's vision, the contract solicitation required a
"demonstrated corporate ability to design environmentally sound facilities." Because
knowledge about green buildings was not widespread in the U.S. at the time, the
responses from A/E contractors enabled EPA to gauge the level of experience,
interest and enthusiasm for the challenge of designing a green building.
Environmental Requirements in the Design Contract
General
Energy conscious design
Highly durable facility design-anticipate a 100-year lifespan
Environmentally-sensitive construction materials and products
Materials and equipment with no ozone-depleting potential
Construction materials with no recycled content
Aggressive recycling plan
Radon free
Water conserving design
Energy Conservation
Daylighting and the optimum use of energy efficient lighting
Life-cycle cost analysis of HVAC systems over a 30-year period
Building Automated System (BAS) for monitoring and control
Indoor Air Quality
Controls for outdoor and indoor sources of indoor air pollution
Detailed site evaluation to determine impact of the site on IAQ
Plan for operation and maintenance of HVAC equipment
Innovative approaches to maximize ventilation efficiency
Evaluation of building materials for potential impact on IAQ
HVAC system that minimize impact on IAQ
Evaluation for air cleaning devices
Make environmental goals for the
facility explicit in the Request for
Proposals and the Program of
Requirements.
Require that the Architect
and Engineer demonstrate both
knowledge about and commitment
to sustainable design.
"The facility shall be designed to
reflect its mission.This translates
into a facility that conserves
energy, efficiently utilizes water,
promotes effective recycling, is
radon free and provides excellent
indoor air quality to its occupants.
The architectural and engineering
design shall implement proven
methods, strategies and
technologies which respect and
protect the environment."
-EPA Program
of Requirements
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
22
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Identify specific environmental
design requirements in the
Architect/Engineer contract.
Engage all team members in
setting project goals including
environmental goals.
Encourage development of
environmental design goals that
are overarching in nature, as well
those that are specific and
measurable.
EPA Campus Project Goals
Top-Tier Goals
Functionality
Environmental design
Low life-cycle cost
Specific Goals
Maintainability
Natural light
Communication
Flexibility
Close proximity/walkability
Security
Development of the FOR for the new facility presented another important
opportunity to steer the project toward its environmental goals. A typical FOR
itemizes square footage requirements by space type and sets standards for the
performance and quality of the facility. EPA expanded this approach through the
inclusion of broad-based environmental design considerations, supported by
detailed descriptions of features to be considered during the design process.
Ultimately the entire FOR, including the environmental design requirements,
became part of the statement of work for the A/E contract.
In addition to the environmental design requirements captured in the FOR, the
A/E contract contained specific deliverables for each stage of the project that
supported the development of environmentally-preferable design options. For
example, there were stand-alone requirements for indoor air quality submittals,
energy analysis and reports, life-cycle cost studies, site surveys, specimen tree studies,
an environmental assessment and documentation of related environmental permits.
Prioritizing Environmental Goals
While EPA set forth a comprehensive list of environmental design requirements
for the A/E team to meet, it also recognized that the entire design team would
need to balance many competing considerations. Consequently, it was necessary to
integrate environmental goals into the larger matrix of goals for the facility as a
whole. The process of prioritizing would also provide an opportunity to build
consensus within the group on the relative importance of the environmental goals
for the project.
As a first step, EPA held a two-day design kickoff session for all design team
members for the purpose of goal setting and team building. During this session,
the group brainstormed a list of primary design goals for the facility. This list was
then discussed extensively to develop consensus within the group and to prioritize
goals. The process of developing goals as a group helped each of the members
develop a sense of ownership of and commitment to these goals.
Among these overarching design goals, functionality and environmental design
were identified as the most important. Cost control was not listed as a priority to
be debated because it was accepted as a given. There was a fixed budget for the
project and that budget could not be exceeded. In terms of functionality, the
facility was being built to support the activities of a diverse group of EPA
programs, and meeting the operational requirements of this work was paramount.
The focus on environmental design goals for the facility was underscored when the
entire team agreed that environmental design was also of primary importance.
With this decision, environmental performance expectations expanded, beyond
what was a collection of contract requirements for specific studies and reports
documenting environmental performance, to become a core issue.
Embedding Green Goals in Conceptual Design
Concept design marks the beginning of the design process. It was during this
phase that the design team began to identify and develop the ideas that organized
the design. There are many issues at the core of green design that need to be
addressed up front, while there is an opportunity to influence the building form
and its placement and orientation on the site. These issues included:
limit disruption to site
' protect wetland areas and existing trees
' develop orientation and massing to maximize daylight access
' develop orientation and massing to maximize energy efficiency
develop orientation to benefit fresh air flows
23
Design Process Discussion: The Right Start
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Design Option Matrix This matrix of design options represents generic
site organizing concepts on one axis and functional concepts on the other.
Schemes were systematically scored, based on how they met the functional
and environmental goals.
During this phase, the A/E created multiple concept diagrams in search of options
that were responsive to the functional requirements of the occupants, and that
held potential for meeting environmental goals. The time invested at this stage of
the design effort later proved invaluable. By systematically searching for a concept
design solution that addressed all key issues, the group avoided the need to make
disruptive changes as the design progressed.
Many of the defining characteristics of the selected scheme made it more
responsive to the environment. For example, an "informal" composition with
buildings and parking decks arranged to fit within the existing site contours was
selected. This arrangement left more of the original site intact. Important natural
amenities were preserved such as the knoll of trees at the high-point of the site,
and the wetlands along the lake edge. This decreased site preparation costs and
disruption of habitat, and reduced the need for stormwater control measures.
Many environmental design solutions provided design benefits which made the
Campus more people-friendly. For example, as visitors come up the drive, they see
the facility revealed one piece at a time. Because the knoll of trees was left intact at
the high-point of the site, only parts of the building are visible from each vantage
point. Just as the preservation of the knoll minimizes the impact on the site, the
limited view of the one-million-square-foot facility minimizes the impact on the
senses, which could have been overwhelming.
In addition to addressing immediate issues of the site, the selected scheme provided
opportunities for future daylighting integration, energy efficiency and features that
would protect indoor air quality. The central atrium which connects the office
tower, cafeteria and conference center with labs and office wings, promotes the
efficient use of daylight. The atrium contributes to energy efficiency by reducing
the overall building surface area, while increasing access to daylight. The narrow
proportion of the office buildings and the perimeter corridor in the lab buildings
also increase access to daylight. To protect indoor air quality in the finished facility,
the fresh air intake vents were located upwind of the laboratory exhaust stacks,
based on prevailing winds.
Explore and test scheme design
options against stated criteria
and goals.
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
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Verify and consolidate program
requirements to optimize facility
size and spatial arrangement.
Explore opportunities to design
with building modules that
enhance long-term flexibility.
Integrate detailed environmental
requirements in the programming
and concept design where
possible, such as elimination of
internal duct lining and planning
for recycling.
Selection of the final scheme required the core group to prioritize and to make
choices that would influence the future performance of the building. For example,
the preferred concept design left long building elevations exposed to low angle
afternoon sun from the west. After analyzing the pros and cons of all of the design
options, the design team placed a higher priority on preserving natural site features
than on providing a north-south orientation for all of the buildings. A north-south
orientation is typically preferred for daylighting because it allows for controlled
daylight to be shared in open office areas. For the EPA facility, the design team
reasoned that the need to preserve wetlands and mature habitat areas was
more important.
Seizing Early Opportunities
As the project moved into schematic design, additional opportunities emerged to
incorporate environmental features. Prior to developing a detailed design solution,
the program requirements were reviewed and verified to identify ways to reduce
space demands. For example, the team developed a system for locating conference
rooms and copy areas in standardized locations which allowed these areas to be
more easily shared. The introduction of a central library and shared support spaces
further consolidated resources and reduced overall space needs.
EPA needed a flexible organizational system that could accommodate changes in
research programs, and changes in the mix of labs and offices with a minimum of
renovation. By placing a high priority on flexibility, EPA reduced future renovation
costs, as well as associated materials use and contribution to the waste stream. The
lab buildings were designed with a designated service corridor and a "flexible zone"
of space parallel to the labs that could accommodate either offices or labs. Office
space standards limited the number of office sizes. Offices are clustered in suites
with fixed circulation patterns to enhance flexibility while ensuring the occupants
access to daylight. Office buildings were designed with approximately half of the
perimeter zone designated as open office areas so daylight can reach interior zones.
A number of fairly detailed environmental requirements needed to be considered
at this stage as well. For example, plans for recycling were developed while the
basic building organization was evolving. The conference center and cafeteria were
located near the main loading dock to enhance materials handling and recycling.
Building circulation routes were developed so that recyclables could be moved
from individual collection areas in the lab and office buildings to the central
loading dock without crossing public areas.
EPAs mandate to eliminate duct lining as a preventative measure had an impact on
the building's structural and mechanical system requirements. EPA requested that
the building be designed without duct linings because they can harbor mold and
microbial growth, becoming a site of potential contamination that is difficult to
localize and expensive to clean. Building ductwork can function well without
linings, however larger ducts are required, and mechanical room layouts must be
meticulously planned so sound can be attenuated. By incorporating this
requirement early in design, the design progressed smoothly and the impact
on cost was negligible.
25
Design Process Discussion: The Right Start
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Design Optimization: A Cyclical Process
As the project progressed into design development, the core design group worked
systematically to "optimize" the design of the new facility. This process involved
the careful evaluation of a broad range of solutions and the establishment of
environmental performance benchmarks to put performance data in perspective.
Advanced simulation tools were utilized to predict energy and daylighting
performance. As concepts were tested, the information base for decision making
expanded and some earlier decisions were revisited. As a result, the design process
was a cyclical one. The willingness of the team to reconsider and revise its initial
solutions to improve the design was important to the success of the project.
Evaluating Criteria/Revising Assumptions
The design criteria for the EPA campus were initially defined by the FOR, EPA
health and safety policies, the federal site master plan, GSA design standards, state
codes and local guidelines. These criteria comprised a set of design requirements
and standards identified at the outset of design. Typically such criteria are accepted
as a given and design options are explored within these parameters. However, the
group found that many of the most innovative solutions that reduced both cost
and environmental impact, came about by challenging and reevaluating these basic
design criteria. For example, they considered everything from the site area,
roadway and utility requirements, to the laboratory exhaust requirements, fume
hood design, office ventilation rates and lighting levels.
When the first round of concept design schemes was developed for the EPA
Campus, the design firm attempted to fit more than one million square feet of
building and 2,500 parking spaces on a 64-acre site. Three stories was the
preferred height for the building initially proposed because it allowed for extensive
use of stairways instead of elevators to enhance communication between floors.
However, evaluation indicated that all of the preliminary concepts would have
profoundly altered the existing character of the site by forcing nearly complete
clearing. To preserve the trees, the design group decided to increase the building
height of the laboratories to five stories. The National Computer Center was
relocated as a separate building on a parcel of land one-quarter of a mile north of
the main campus. With the least day-to-day interaction with other EPA programs,
the Computer Center was the logical choice for relocation. Still, the distance
between the two facilities is an easy five-minute walk.
Even with revised massing to allow for taller buildings and a reduced footprint,
much of the site area would be impacted by buildings and parking. However, the
revised design parameters provided the group sufficient flexibility to preserve
important natural features leaving the knoll of mature trees at the high-point of
the site, the site's wetland areas and major drainage swales largely intact. Decked
parking, which is rarely utilized locally, would also limit paved area.
As the site design progressed, more design features were revisited. For example, the
number of parking spaces was revised from 2,500 to 1,800, the access roadway
through the site was revised from four lanes to two, fire lanes were rerouted,
electrical ductbanks were relocated to beneath the roadway, and curbs and gutters
were eliminated in favor of grassy swales and bio-retention. Each of these decisions
required the design team to challenge components of the original design criteria.
Maintaining flexibility, within the constraints of schedule and cost, the group
proactively searched for solutions that were cost-effective, practical and
environmentally-preferable. The resulting design evolved and improved over time.
Encourage open dialogue within
the team so that members will
challenge basic assumptions as
appropriate to improve the design.
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
26
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Energy Performance
Benchmarks
The U.S. Department of
Energy documents commercial
buildings energy consumption and
expenditures in the United States
for the purpose of benchmarking
commercial building energy
performance, including office
buildings, educational buildings,
health care buildings and
laboratories. Primary energy use
characteristics examined include:
Gross energy intensity
Energy expenditures by fuel type
Rocky Mountain Institute
(RMI) in Snowmass, Colorado, also
benchmarks building energy
performance including
Gross energy intensity
Connected interior lighting load
Plug load, as used
Mechanical-cooling sizing
Whole system cooling
Air handling intensity
RMI's benchmark figures are
provided for average, good
practice and advanced practice.
American Society of Heating,
Refrigeration and Air
Conditioning Engineers
(ASHRAE)
Develops standards for
the design of HVAC systems
Develops and does research to
produce a set of reference
books for the design of heating,
refrigeration and air
conditioning systems
Organizes conventions and
meetings to review new
equipment and discuss
innovations in the industry
Is considered by most building
codes to be the standard for
design of HVAC systems
A re-evaluation of energy criteria was critical to the success of the design. Since the
laboratories represented the largest portion of overall energy use, labs were given
especially close scrutiny. Ensuring the safety of laboratory workers who must
handle hazardous substances on a daily basis was of highest priority. Ventilation
was designed to use 100% outside air and to provide 12 to 15 air changes per
hour (ACH) so that any contaminants would be quickly exhausted. After intensive
analysis, the design team was able to present alternatives to EPA safety officers that
satisfied concerns for uncomplicated, fail-safe solutions. Safe, simple and effective
energy savings were realized by linking the full closure of fume hood sashes with
room light switches. The normal exhaust ventilation rate is reduced by half when
research staff close fume hood sashes and turn off the lab lights as they leave for
the evening.
Unfortunately, some of the design criteria that made sense when considered in
isolation proved to have a ripple effect on other areas of the design that led the
group to reconsider. For example, the requirement for six ACH in the office areas
seemed to be beneficial in terms of indoor air quality, because it boosted the
supply of fresh air. However, when energy modeling predicted that the energy
consumption would be much higher than was anticipated, the group began to
re-evaluate the issue. To test the validity of the air change requirement, common
contaminants known to be emitted in office environments due to occupants and
furnishings were "modeled" using a computer program called "Exposure."7 This
study led to a reduction of air change rates to a minimum of four ACH that
maintained good indoor air quality, while improving energy efficiency.
Identifying Performance Benchmarks
During design, the design group found that identification of performance
benchmarks was key to a successful multidisciplinary design dialogue. These
benchmarks, which identify both "typical" and "improved" performance, allowed
group members to become informed participants in a discussion that would
otherwise have excluded them. For example, when architects were able to talk to
electrical or mechanical engineers about energy consumption in BTU per square
foot per year, they were better able to measure the value of proposed design
solutions. These measures gave both specialists and non-specialists some insight
into when the design was "on track," and when it could be improved.
When the design team first evaluated the energy performance of the building as
designed, members were shocked to find that the design was not only inefficient,
it was worse than the "standard" benchmark values. Although, the engineers were
using typically energy efficient components in the building, such as outside air
economizers, automated lighting controls, and high efficiency chillers, boilers, fans
and motors, the full benefits were not being realized. The use of energy efficient
equipment, without design refinements and systems integration, created a poor
result. Because the results of the energy modeling could be compared to a set of
benchmark values for typical energy performance in similar buildings, the group
was alerted to the need to refine the design. This led to a series of revisions to the
HVAC design that ultimately reduced energy consumption considerably.
The design team also searched for benchmark information to guide other aspects
of the design. For example, the key source of benchmark information for indoor
air quality was the innovative program developed for the State of Washington. By
studying the details of the Washington program and analyzing its strengths and
weaknesses, the group could build directly on earlier efforts and propose a series
of refinements.
27
Design Process Discussion: Design Optimization
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Using Models and Evaluation Tools
As the design group evaluated options, models and other tools that simulate
future performance became essential aids to decision making. Computer and
physical models were used for water quality calculations and air flow modeling in
the labs. Wind tunnel testing was used to study air dispersion from the exhaust
stacks outside the labs. These simulation models provided information that led to
numerous design refinements.
Modeling Resources
' "Trace"5 by the Trane Corporation for energy modeling
"Lumen Micro"6 and physical models for daylighting evaluation
"Exposure"7 an EPA program for indoor air quality
Modeling, however, can improve the environmental performance of a facility
only when it informs the design process. Typically design teams employ energy
modeling for sizing HVAC systems and estimating energy consumption, with little
or no effort spent on testing alternatives and optimizing performance. When the
energy model was used as a design tool to optimize performance, modifications
made to the building design and HVAC systems improved performance from
substandard, based on DOE benchmark values, to more than 40% better.
Energy design optimization began with an assessment of baseline energy loads in
the lab and office components of the building. This was important because the
load profiles, which were extremely different for the lab and office portions of the
building, would guide the group to focus on load reduction strategies which
would have the greatest impact.
As the design was further defined, the energy models required refinement. The
group reviewed all of the inputs into the energy analysis program and updated
them with the anticipated operating load profiles. These profiles incorporated
diversity factors that captured such items as areas of the building not fully occupied
at the same time, and that reflected "as-used" loads instead of "connected" loads for
lighting and power. In the office areas, the as-used loads suggested energy savings
from occupancy sensors, daylight dimming and computer "sleep modes." In the
labs, as-used loads factored in the multiple ways the labs are used, such as partial
combination of occupied and unoccupied labs and night-time airflow setback.
Search for environmental
benchmarks and performance
measures.
Begin energy modeling while
there is sufficient time for the
modeling results to inform the
design process.
Carefully review engineering design
criteria as standards have changed
over time. Oversizing and
overlighting increases energy use,
first costs and operating costs.
Do not rely on "rule of
thumb" design.
EPA CAMPUS COMPONENT PEAK LOADS
LABORATORY
Total Load 64 MillionBtu/Hr
supply fan
8%
envelope
2%
OFFICE
Total Load 18 Million Btu/Hr
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Computer modeling also was used to create a quality assurance mechanism for
indoor air quality requirements. A set of emissions thresholds was established based
on what would be both acceptable and achievable, and predictive modeling was
performed to confirm that emissions thresholds could be met. Based on that
predictive modeling, EPA was able to assure prospective contractors that if building
materials passed the emissions testing requirements, the building would also pass
baseline indoor air quality testing requirements after construction was complete.
During the evolution of the new EPA Campus project, several rating systems for
sustainable buildings emerged. Canada and Great Britain unveiled two of the
earliest whole-building assessment tools in 1993. Along with fledgling initiatives in
the U.S., the Netherlands and a handful of other countries, these early rating
systems helped spark an international effort in 1998 that created the Green
Building Challenge (GBC). Led by the Canadians, GBC aimed to establish
international comprehensive benchmarks for environmentally-responsible building
and site design from an environmental perspective. The new EPA campus was one
of 30 case studies evaluated by the 14 participating countries in the prototype
round of GBC.
In 1999, the U.S. Green Building
Council established the Leadership
in Energy and Environmental
Design (LEED) rating system.
LEED evaluates environmental
performance from a "whole
building" perspective over a
building's life-cycle.
When researching environmentally
preferable building materials,
gather specific information about
products by manufacturer, rather
than generalized information
about product types, whenever
possible.
In the United States, the U.S. Green Building Council first established its
Leadership in Energy and Environmental Design (LEED) rating system in 1999.
LEED evaluates the total environmental performance of a building during all
phases of its useful life, from construction through demolition. Although LEED
emerged too late to be of use in designing the main facility on the EPA campus, it
was applied to the redesign of the National Computer Center-a separate 100,000
square foot facility on the campus. The computer center has been designed to meet
the "gold" rating criteria under LEED.
Although the international and national green building standards offer the
advantage of benchmarking performance based on broad consensus, they do face
some challenges. For example, it has been difficult to adjust for the local effects of
climate, markets, transportation infrastructure and other locale-specific factors.
Recognizing this, a number of communities and regions have brought forward their
own systems. In the Research Triangle area, the Triangle J Council of Governments
performed a detailed adaptation of LEED to create their own "High Performance
Guidelines: Triangle Region Public Facilities" (HPG). EPAs new campus design
team helped create the HPG guidelines, which were issued in 2001. The Agency
will incorporate them, along with LEED, into the EPA/NIEHS child care center
design-build contract.
Researching Environmental Impact
The search for physical solutions to established goals and design criteria led to
supplemental research to understand the environmental impact and identify
preferred approaches. In some areas, such as energy and water use, the research
required proved to be minimal. However in other areas, such as building materials
selection and specification, extensive research was necessary to develop resources
that did not yet exist.
Civil engineers performed feasibility studies to explore cost-effective stormwater
management options to effectively cleanse runoff, while minimizing site impact.
The bioretention strategy that was ultimately selected was a relatively new
approach relying on "pocket wetlands" filled with permeable planting soil and
plantings to accelerate the natural processing of contaminants suspended in the
stormwater runoff. Since this technology had never been used in North Carolina
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Design Process Discussion: Design Optimization
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at the time, the civil engineer had to educate regulators in North Carolina about
successful bioretention systems in Maryland in order to use it on this project. This
effort helped lead North Carolina officials to adopt bioretention as a Best
Management Practice for stormwater treatment across the state.
Other site issues requiring research included native plantings such as wetland and
wildflower species, alternatives for erosion control, permeable pavement options,
performance of recycled content roadway materials and re-use of on-site materials.
Specialty consultants joined the project team to develop the wetland plantings and
wildflower specifications. Topics were investigated by the civil engineers, who
applied skepticism, logic and common sense to test the performance of each
proposed alternative material.
Environmentally preferable materials selection was a major issue requiring
extensive research. Early in schematic design, the design team determined that
although some sources of information were available to guide decision making
about environmentally preferable products, such as the AIA's Environmental
Resource Guide (ERG), manufacturer specific information regarding the
environmental performance of individual products did not yet exist in any
published form.
In response to this information void, the A/E voluntarily initiated an effort to
gather life-cycle environmental impact information about products. With input
from experts in the green building field, the A/E developed a product
questionnaire that was sent to every manufacturer considered for use in the
project. Response to the questionnaire was good, and the data proved useful in
defining which products would be the best choices for the EPA project.
The concept of "materials benchmarking" also added an important dimension to
the research effort on environmentally preferable building materials. It led the group
to explore the range of materials and products on the market, and to compare them,
by developing benchmarks for materials. The research effort eventually extended
beyond the products and materials to considerations of how the materials were
installed, when they would be installed and, due to their potential impact on indoor
air quality, how they would be maintained. This focus on IAQ led to requirements
for emission testing of selected materials, so the potential impact on indoor air
quality could be evaluated before materials were installed, rather than later, when
the cost of removing them or mitigating their effects could be prohibitive.
In addition to requiring emissions data, the group collected IAQ specifications
and related information from other projects with an indoor air focus, and
prudently reviewed them to develop uncomplicated procedures to safeguard IAQ
during construction. For example, instead of a 90-day "flush out" period which
would have required the building to remain empty while it was ventilated prior to
occupancy, the group opted for ventilation during construction. This requirement
was coupled with IAQ testing to document air quality prior to occupancy, thereby
ensuring that chemical vapors emitted during construction had been removed and
air quality in the building met the established indoor air quality standards.
Other issues, such as the potential impact of electromagnetic fields on the health
of building occupants, represented entirely new territory that required extensive
research. Local issues, such as the details of the recycling infrastructure available in
North Carolina, required research as this information is regionally specific and
changes over time.
Environmentally-preferable
building materials
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Green Team Core Members
Although the entire team was
committed to producing an
environmentally sound design,
certain team members had
especially critical roles in keeping
the green building effort focused
and on track.
EPA Project Manager
Responsible for balancing
environmental goals against the
pressures of meeting cost,
performance and schedule
requirements.
EPA Environmental Advocate
As a member of the EPA project
management team, had the special
role of questioning all design
decisions for their environmental
merits.
Environmental Scientist
As a member of the EPA research
community and the original
project officer for the
Environmental Resources Guide,
provided expert advice to the
core design group on a range of
pollution prevention and
sustainability issues.
Indoor Air
Quality Coordinator
A mechanical engineer and indoor
air quality researcher for the EPA;
oversaw the development of the
IAQ manual and reviewed the
design for indoor health impact.
Project Engineers
The EPA's lead technical staff;
directed the actual
implementation of green design
decisions.
A/E"Green Team" Leader
As part of the lead architectural
firm, had the task of assuring the
environmental soundness of the
complete range of architectural
and engineering choices made on
the project.
Greening the Team
Even though the design team understood the need to improve the environmental
performance of the facility, the design process itself involved dozens of people
working simultaneously on an assortment of tasks. Because of the complexity of the
design and the variety of demands on all team members, the project leaders worked
on greening the design team itself, to ensure that the project's environmental goals
would not get lost in the process.
Unlike most organizations, EPA is fortunate to have its own in-house experts
on pollution prevention, indoor air quality, energy conservation, recycling and
a variety of other environmental issues. EPA invited input from these in-house
experts in planning for the new facility, and the project benefited from their
insights. The ultimate success of the project, however, would be determined by
the extent to which EPA could engage all project team members in integrating
environmental design issues into the creative decision making process.
Environmental Champions on the Team
While many design team members contributed their expertise and insight
to the development of environmentally preferable solutions, EPA and the A/E
each recognized that it was extremely important to have an individual with an
understanding of the whole "champion" the environmental goals for the project.
EPA and the A/E each designated an "environmental advocate" to guide the design
internally, while also reaching out to the local sustainability network for additional
support. Environmental advocates were tasked with monitoring and supporting
environmental initiatives incorporated in the design. These advocates searched for
information that enabled the design team to assess environmental impact, raise
issues and identify strategies to consider, and facilitate the development of design
solutions requiring multidisciplinary collaboration.
Local Sustainability Network
In addition to the project team that had been assembled to design the new EPA
Campus, many others contributed throughout the process. A community of
people involved with issues relating to sustainable design and green buildings
provided crucial voluntary assistance. These independent resources in the design,
academic and nonprofit communities provided valuable input. For example,
volunteers linked the group with local recycling resources, identified successful
demonstration projects that could serve as models, and assisted the A/E with
technical information relating to emerging issues such as design for good indoor
air quality and environmentally preferable materials selection.
EPA also organized a voluntary committee from within its own ranks called the
Pollution Prevention Committee, to support the design effort. Meetings were held
early during schematic design, which led to the creation of an extensive list of
green design strategies to be considered. Some of the members of this group
remained involved as advisors to EPA to assist during design reviews. The
Pollution Prevention Committee was a great mechanism for broadening
involvement and generating ideas that spanned many disciplines.
Integrated Team Approach
Recognizing that optimal sustainable design strategies rely on synergy achieved
when one solution addresses multiple objectives, the design team collaborated by
physically working together. Work sessions and design reviews included EPA, the
A/E and its consultants. Though this collaboration required the group to spend
more time in meetings, the design process as a whole became more efficient.
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Design Process Discussion: Greening the Team
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Design integration leads to more optimal solutions, reduces backtracking and
relieves the need to spend extensive amounts of time "coordinating" the various
disciplines after the fact.
For example, architects, interior designers, mechanical/electrical/plumbing (MEP)
engineers, civil engineers and others needed to collaborate closely to create a site
plan and building massing that would balance a diverse set of functional and
environmental goals. Interior designers provided input on site orientation and
building massing based on how it would impact future interior planning and
daylight access. MEP and civil engineers integrated issues that might otherwise have
been deemed "secondary," related to site infrastructure, underground utilities and
fire lanes. The "integrated" design scheme worked within the existing site contours,
allowing large portions of the site to remain forested and preserved wetland areas.
Another benefit of the integrated approach was that non-experts included in
design discussions could offer a fresh perspective. For example, when water quality
ponds emerged as the strategy of choice for stormwater treatment because of
greater effectiveness, lower cost and use of natural methods to purify the water, the
engineers did not focus on the impact that the pond would have on the landscape.
Though the ponds were not large, the grading necessary to direct runoff toward
them would have altered much of the landscape and required tree clearing for
vast portions of the site. In one of the regularly scheduled design meetings, a
nontechnical person asked the obvious question: "Look how many trees are being
cut down to 'save the environment' isn't there a better way?" This fresh perspective
led to a reinvestigation of options and to the less disruptive "pocket wetland"
bioretention method that was adopted.
Maintaining the Commitment
The challenge for any project, regardless of the investment of energy into careful
project planning and team building, is the follow through. The effort spent
defining goals, evaluating options and performing analysis to identify the best
integrated design solution can all be lost in one misdirected value engineering
session. Likewise, for a successful project, the construction detailing and
specifications must be developed to support the environmental design strategies.
Performance tracking, green value engineering and partnering for construction
were other strategies that proved to be instrumental in maintaining a focus on
the environmental goals for the facility.
Following Through on the Details
Specifications and construction details are "conventional" by their very nature,
because design professionals protect themselves from risk by relying on methods
that have worked successfully in the past. Specifications and details are also heavily
influenced by third parties. Material suppliers can limit or revoke warranties if
manufacturers' recommendations are not followed. Equally true, however, is the
fact that specifications and construction details continuously evolve in response to
innovations and changing requirements. The challenge was to direct review toward
more sustainable solutions. Each modification to conventional practice required
extensive investigation to ensure that no element of building performance would
be compromised.
Specifications not only document choices about which materials are to be used,
but also provide information about secondary materials such as adhesives and
finishes. In some cases, options were provided and the specifier simply needed to
Identify environmental champions
on both the owner and the A/E
teams.
Identify local groups
dedicated to sustainable design
that can provide information or
design assistance.
Clearly describe performance
requirements in the specifications,
and require submittals to certify
that requirements have been met.
Review the specifications with an
eye to making environmental
performance improvements
wherever possible.
Use Division One of the
specifications to summarize
atypical environmental
performance requirements.
When developing specifications,
consider the environmental and
IAQ impact of adhesives and
finishes, as well as the specific
materials.
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32
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Track the development of
contract documents thoroughly
to ensure successful inclusion of
environmental design features.
choose the option that was environmentally-preferable. For example, nearly every
flooring manufacturer either makes a zero-VOC adhesive, or has approved one,
though they may still carry the old higher-solvent formulations. In other cases,
such as the high performance finishes required in the laboratory environment,
research was needed to identify alternatives to finishes that are standard in the
industry, but factory applied.
The team also anticipated challenges that might occur during construction.
By painstakingly defining environmental performance requirements and the
submittals required, alternate products proposed for substitution were screened
for environmental performance.
Division One of the contract specifications was developed specifically to highlight
unusual environmental requirements. Division One of the specifications contains
the project General Conditions, key non-technical requirements for the prime and
all subcontractors. By summarizing environmental requirements in this initial
section as well as in the technical provisions that follow, EPA was assured that the
contractor understood the environmental requirements from a "big picture"
perspective. A new section, Environmental Impact of Materials, was created to
diminish the possibility that either contractors or subcontractors could
misunderstand environmental requirements. Cross-referencing between this
section and the individual specification sections provided clear and consistent
documentation of environmental requirements.
Unique specification sections were developed for Division One to clarify atypical
construction procedures. At the beginning of the project manual, a section entitled
Environmental Requirements, simply describes EPAs environmental goals for the
project. The section begins with the following statement: "It is the goal of the EPA
to integrate the Agency's mission into this project as much as feasible and practical;
i.e., to construct a green building." Other Division One sections include Testing for
Indoor Air Quality, Baseline IAQ and Materials; Sequence of Installation Finishes; and
Waste Material Management and Recycling. Detailed commissioning requirements
are located in the mechanical and electrical sections to ensure that the building will
operate properly, and that energy savings will be realized.
Tracking Environmental Performance
The core design group found that mechanisms to track environmental
performance were especially essential in the later phases of the project. The
number of decisions made on a daily basis would multiply as the project moved
into the final stages of design. Tracking environmental design strategies helped
highlight the "non-standard" features requiring special attention.
The tracking process involved ongoing design review as well as periodic
reporting. A detailed report issued at the end of Design Development itemized all
environmental features incorporated into the design. The report was organized by
design topics: Site Design, Energy Conservation, Water Conservation, Building
Materials, Indoor Air Quality and Waste Management. The design strategies
suggested by EPA's Pollution Prevention Committee were tracked in the report as
well as additional issues identified along the way. The report contained an energy
budget, which predicted future energy costs through computer modeling, and a
description of all of the energy conserving features of the design. This report,
updated and reissued at key milestones, led to a series of itemized checklists that
were distributed to project team members from each discipline.
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Design Process Discussion: Maintaining the Commitment
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Summary of VE cost savings during the Design Development phase
STRATEGY
Roadways and
Utility Lines
Stormwater
Atrium Skylight
Laboratory
Exhaust Hoods
ENVIRONMENTAL
BENEFIT
Depart from federal site master plan requirements for Greatly decreased road and
4-lane roads plus utility easements; design 2-lane roads and utility footprint - preserving site
bury electrical and communication lines under the road woodlands and wetlands
Replace curb and gutter and oil-grit separators with
grassy swales, water quality ponds and bioretention
Revise from all glass to one third glass, one third
insulated translucent panels and one third solid
Install 250 specialized fume hoods and exhaust systems
that reduce total air flow demand by 50% and eliminate
dozens of fans
Improved on-site treatment
of stormwater
CONSTRUCTION
COST SAVINGS
$2 million
$500,000
Improved energy performance and indoor $500,000
environment-thermal comfort
and light quality
Prevents consumption of large
qualities of conditioned air
$1.5 million
LIFE CYCLE
COST IMPACT
Less maintenance
and repair cost
No increase or decrease
Lower energy cost
($50,000 / year)
Lower energy cost
($1 million/year)
While the checklists served as a reminder of the decisions that had been agreed
upon, design reviews were also necessary to correct misunderstandings that would
emerge. For example, at one point late in the construction documentation phase,
it was discovered that a lighting designer had introduced a large quantity of
inefficient incandescent light sources in the entry lobby of the main facility to
make the space feel "warmer." The design team had worked hard to develop a
pleasing, energy efficient, lighting scheme. When it was brought to the group's
attention, the interior designers clarified that although fluorescent lighting may
have seemed unconventional in a lobby space in the past, color rendition of
compact fluorescent lamps had improved tremendously. If necessary, the
coloration of the space would be fine-tuned by adjusting the stain on the wood
panels and the paint on the walls. As a result, the construction documents were
changed and the fluorescent lighting was maintained.
Using Green Value Engineering
Throughout the design process, the issue of cost, and particularly the cost of
green design strategies, was scrutinized judiciously. In addition to ongoing analysis
of options by the cost consultant and a member of the core design group, EPA
chose to engage in focused Value Engineering (VE) reviews. VE is often seen as
the enemy of good design in general and green design in particular. At its best
however, VE is not merely a cost-cutting exercise, but a review process to enhance
"value." EPA used the VE process to balance cost, function and environmental
performance when considering options.
The VE process became especially important when extraordinary challenges
were introduced by the political process that is unique to the design of a large
government facility. When the U.S. Senate was considering appropriations for the
new facility, they asked EPA to review the project again to see if the total cost
could be significantly reduced. This challenged VE participants to produce creative
cost reductions without compromising functionality, reducing program area or
compromising environmental goals. The core design group not only reduced the
total project cost by approximately $30 million, but the VE cost-reduction exercise
produced a greener building.
Encourage the VE process to
balance cost, function and
environmental performance.
Include designers and
environmental advocates on
theVE review team.
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
34
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Encourage the development
of VE proposals by interdisciplinary
teams to promote integrated design
solutions.
-
Educate all members of the
construction team about the
project environmental goals.
Encourage contractor to join the
project as a partner, and contribute
to development of creative,
environmental design solutions
during the construction phase.
One reason the VE sessions were so successful was that the inclusive process
allowed for informed, interdisciplinary brainstorming to occur. Led by a special
VE group of the Army Corps of Engineers, the design team, participated in the
brainstorming of VE proposals, ensuring that the finer points of the design were
not overlooked. Together, we worked to save money retain the functional needs
and keep the project green all at once.
Given the tremendous pressure to reduce the first costs of the design, it is
surprising that many of the environmental features that required a first-cost
investment remained. Fortunately, the team recognized the importance of looking
at the project and the budget as a whole, not simply line by line. While energy
and water conservation, and materials minimization would be economically
justifiable, either in terms of first costs or life-cycle costs, other environmentally
beneficial strategies would not provide an immediate dollar payback. By
considering value broadly and making design trade-offs in other areas, EPA
justified design decisions that might never have survived purely economic scrutiny,
such as the use of certified sustainably-harvested wood.
The VE modifications are interesting to study both for what they contain as well
as for what they do not contain. Difficult choices were made, and the trade-offs
reflect the values of EPA. For example, EPA replaced the slate flooring in the
public areas with ceramic tile, but chose not to delete humidification from the
office buildings, because it would contribute to occupant comfort over the long
term. Rather than delete occupancy sensors, which save energy by turning off lights
when people leave their offices, EPA decided to omit doors on suite entryways.
Rather than use wood paneling that was not from independently-certified
sustainable sources, the group chose to reduce the amount of wood paneling,
using it in small quantities in public areas. Sidelights, which bring daylight into
the interior closed offices, were also maintained by making similar tradeoffs.
One of the most important VE issues involved the decision to keep structured
parking rather than all surface parking. This decision alone represented several
million dollars that might have been spent on the facility, however, it emphasized
the undeterred commitment to value the site environment. EPA felt strongly that
use of all deck parking, which would have required the clearing of an additional
15 acres of land, disrupted wetland areas and existing drainage patterns, and
eliminated nearly all tree coverage on the site, was not acceptable. To compensate
for the cost impact of the decision, the quantity of on-site parking was reduced by
25%, and EPA made a strong commitment to create incentives for
employees to use alternative transportation.
Preparing for Construction
Recognizing the size and complexity of the new campus, EPA selected the
GSA as construction manager for the project, due to their expertise with
large-scale construction.
Unfortunately, when the construction procurement was initially advertised and
competitively bid, the bid prices exceeded the project budget. This raised the
question, "Did the bids come in higher because of the environmental
requirements?"
EPA and GSA invited the bidders to comment on what could be done to
reduce the cost of the project. It is interesting to note that only two of the many
comments received were related to environmental features of the design. One
contractor commented that the "wet sponge method" for finishing drywall, which
35
Design Process Discussion: Maintaining the Commitment
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was specified to protect construction workers and the building from silica dust
released into the air with dry sanding, added 50% to the cost of the gypsum board
installation. In the end, a conventional gypsum finishing method was permitted,
since a requirement by the contractor to seal off ductwork during gypsum
finishing, and to clean the ductwork prior to building acceptance would already
ensure dust-free ventilation systems. A phased installation sequence would also
keep carpet out of work areas until dusty wallboard work was complete.
The other comment that EPA received from the contractors related to the detailed
emissions testing of material assemblies. Originally all materials that would have a
potential impact on IAQ were to be tested. It was expected that the cost of testing,
an extremely small portion of overall cost, would be borne by manufacturers eager
to participate in the project. Faced with budget concerns, and the fear expressed
by contractors that the procedure could get lengthy and complicated, the
specification was revised on the basis of relative contribution to the office air
zones. Four assemblies which presented the greatest exposed surface areas were
tested for emission potential-wall paint, acoustical ceiling tile, spray-on
fireproofing and carpet. This change reduced the paperwork burden and much of
the perceived risk for contractors while allowing EPA to retain stringent
environmental constraints on the materials used in the project.
Though the economic analysis and information from contractors indicated
otherwise, there was tremendous temptation to remove many of the green
specifications from the project because of the concern that they were related to the
cost overrun. Fortunately the group had addressed cost issues throughout the design
process, and the research on the cost and availability of environmentally-preferable
materials was well documented. Except for the two issues previously noted, the green
specification was maintained in the next set of construction documents.
The project's actual bid price compares favorably with government industry and
academic facilities of similar scope. The design team's research efforts and practical
approach had kept the cost of the green design well within industry standards.
When GSA selected a general contractor, a new member and potential collaborator
joined the team. At this time, the A/E introduced a construction administration
team that contained some new players, though the environmental advocate roles
were maintained.
The final preparatory phase prior to construction involved a partnering session to
focus the newly formed construction team on working together to enhance safety,
quality and environmental performance. The session included a presentation of
the environmental goals for the facility and a viewing of a training video on
environmentally friendly construction practices created especially for this project.
The video was required viewing for every construction worker on the site to teach
the construction team about environmentally-sensitive practices during construction
and to explain its importance. The expectation was that construction workers and
managers, inspired by the goals of the project, would be motivated to become
willing partners in the creation of an environmentally-friendly construction site.
The signed partnering charter included a commitment by all parties to
environmental, safety and quality goals.
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina 36
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Conclusion
When EPA and its partners began the long process of designing and constructing
this project, sustainable buildings were in their infancy. Reference material for
architects, engineers and builders was extremely limited, and few green building
case studies had been documented. The design team did not let this stand in the
way of its goal.
In the absence of a full set of tools and resources, the design team recognized that
creating a sustainable campus would require a new process based on a new way of
thinking. The commitment to question, research and evaluate every possible
component of the building process was the key to making their goal a reality.
Early on, the group embraced the commitment to a sustainable process and
upheld it throughout design and construction.
The success of this project was based on the strong emphasis on environmental
quality that has traditionally been placed only on cost and functional performance.
Just as our focus on cost helps us realize better value in everyday life, the
environmental consciousness of the EPA project has yielded an improved value in
the construction of the campus. This represents a shift in thinking that is much
more significant than any individual tool or reference material.
During the past decade, there have been huge advances in sustainable building.
Through this project and others, the building industry is learning about
sustainability and incorporating it into its work. Advancements are likely and it is
EPAs challenge to stay abreast of new technologies and practices as they relate to
managing and operating the Campus. The design team recognized this need and
left room for improvements to be made. For example, heat recovery units for the
lab exhaust system were not justified by meager energy savings, but space was
accommodated in the laboratory penthouses so they could be added in the future
if costs become competitive.
EPA has continued to set aggressive goals for sustainability, seek fresh ideas, gauge
progress and make improvements. Without the momentum of construction it
might be hard to maintain this focus, so the EPA Campus team has taken a few
steps to avoid complacency. To unearth new innovations, an advisory committee
now focuses on sustainable
building and site operations. EPA
has also worked out an agreement
with the local power company to
install solar-powered street lights,
and has arranged for two local bus
systems to pick up and drop off at
the front door of the Campus.
With construction complete,
EPAs goal will be to operate the
facility in an environmentally
responsible manner.
With a dedication to continual learning and a commitment to constant improvement
throughout the life of this facility, EPA will continue to advance sustainable building
concepts and preserve the strong educational value of the campus.
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Design Process Discussion: Conclusion
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DESIGN ISSUES
DISCUSSION
Site Design
While the challenges of environmentally-sensitive site design for projects located in
urban, suburban or rural settings vary and the solutions can differ, the overall issues
are largely the same. These issues involve disruption and displacement of wildlife
habitat, increased erosion, diminished ground water recharge and threats to the
water quality of surface water bodies and aquifers.
Minimize Site Disruption
The issue for the EPA in RTF was not where to build its new facility, but how to
best build on its land. The site, an undeveloped tract of abandoned farm land, had
been deeded to the federal government in 1968 for federal environmental research
facilities. Site features include a man-made lake, a wooded knoll, a pine and
hardwood forest and wetlands. The site's elevation varies considerably and the
rolling topography creates distinct ridges and valleys that drain into the lake.
Low-lying areas and drainage swales support mature hardwoods and wetlands,
which contrast with a densely wooded knoll, sixty feet higher at the site's center.
The primary challenge of the site design for the EPA Campus was to accommodate
the needs of the building and sitework within the existing ecosystem with a
minimum of disruption. After a thorough evaluation of the site's natural features,
topography and hydrological systems, the EPA project team developed a site plan
that would reduce large scale disruptions and protect some of the site's unique
natural assets. The plan limited the size of the development footprint and controlled
other site components such as underground utility lines, and construction grading
and staging areas.
Following conceptual design, a decision was made to expand the 64-acre parcel
of land originally set aside for the project to 133 acres. This did not require the
acquisition of additional land since the original site, deeded to the government in
1968, was approximately 500 acres. Half of the land had been developed by the
National Institute of Environmental Health Sciences with the other half reserved for
EPA. At the same time, the design was changed from a three-story campus to a
series of three- to six-story buildings to minimize the total building footprint.
The final design for the EPA Campus organized laboratory and office buildings
and the accompanying site infrastructure within existing site contours. This
reduced the building's impact on forest, wetlands, wildlife habitats and drainage
patterns, by greatly reducing the need for regrading at the building perimeter. The
high point, a wooded knoll at the center of the site, was preserved intact and was
highlighted by the entry drive that encircles it. The use of structured parking
decreased the overall size of the development footprint. In addition, EPA's
commitment to carpooling and alternative means of transportation reduced the
parking requirement by hundreds of spaces. Site utilities and emergency access
lanes were carefully routed to be near the building and within areas that were
already disrupted for roadway construction.
Key Issues to Consider
Rehabilitate an existing site or
redevelop an urban infill site,
when possible
Develop compact massing to
preserve open space
Preserve natural vegetation,
water sources and topography
Preserve and enhance wildlife
habitat
Consider use of pervious paving
materials to minimize
impervious coverage of the site
Consult with site analysis
drawings and tree surveys
before beginning design
Plan to save trees during and
after construction
EPA site before construction
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
38
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Statistics
Site: 133 acres
Building: 10.05 acres
Paved Areas: 16.9 acres
100% surface parking study
Site plan of final parking design
with both structured and surface
parking
Structured Parking
Parking decks and public transportation are two approaches for preserving green
space and limiting dependence on the automobile. Two factors typically drive the
selection of structured parking: construction costs and space limitations. The unit
cost for structured parking is typically about four times the unit cost for surface
parking. In addition, land is readily available in RTF and the zoning codes permit
nearly unrestricted use for parking. Consequently, the project team's specification of
structured parking represented a departure from standard practice in the RTF area.
However, a study of an "all-surface" parking alternative revealed that the cost of
surface parking on the site would be a little higher than average because of the need
for additional grading, retaining walls and stormwater management. The all-surface
parking scheme would have covered an additional eight acres, requiring greater
forest clearing and disrupting drainage patterns and wetlands. Though the all-
surface parking scheme would save several million dollars, EPA opted for the more
compact design, which would use a mix of surface and structured parking.
To offset some of these costs, EPA reduced the overall parking requirements by
about 25 percent. To minimize the impact of reduced parking on employees,
EPA is creating incentives for carpooling and is exploring alternative means of
transportation. Easy access to public transit systems has also been provided. The
decked parking actually provided better service to employees and visitors by
bringing more parking closer to the buildings.
Fire Lanes
Fire lanes are required by code to provide fire truck access to all parts of the
Campus' buildings. While essential for safety, fire lanes have the potential to wreak
havoc on tree-preservation strategies. These access lanes generally require a clear,
level and permanently unobstructed zone that is a minimum of 36 feet wide and 10
feet away from the building. If the fire lane is not a continuous loop, turnaround
areas that are at least 100 feet in diameter must be provided.
To reduce the impact, the EPA project team worked closely with the local fire
marshal to develop a plan to meet all requirements and minimize site disruption.
39
Design Issue Discussion: Site Design
-------
The plan calls for the development of roadways on the entry side of the site for fire
truck access and a grass paving system for most of the fire lanes to the west, so that
total impervious surface on site could be minimized.
Erosion Control
Reducing the loss of valuable topsoil was particularly important on the EPA site,
not only to protect on-site streams but also the man-made lake from sedimentation.
Developed in accordance with North Carolina Sedimentation Pollution Control
requirements, EPA's erosion control plan included specifications to guide construction
and maintenance of the erosion control features. Plan measures included tree protection
devices, temporary perimeter diversions and sediment traps or basins, and silt curtains
across lake inlets. The plan also specified dust control measures and required the
stabilization of disturbed areas with temporary seeding. Topsoil removed from the site
and stockpiled for reuse was temporarily seeded.
Site planners and civil engineers worked closely with the rest of the project team to
develop an erosion control plan that is integrated with the design, and meets the
overall environmental goals for the project. When details of EPA's erosion control
plan were reviewed, it was determined that the standard list of materials approved
by the state for stabilization of temporary coverage included some materials, such
as asphaltic tackifier, that were undesirable from an environmental perspective.
The specification was revised to allow only biodegradable, nontoxic substances to
be used for soil stabilization, and to require the use of 100% recycled content
hydromulch in the seeding around all Campus buildings.
Loop Road
The 1970 U.S. Public Health Service Research Park Master Plan, that addressed the
entire 511-acre campus in RTF, specified a four-lane loop road to provide access to
all buildings. The plan also identified an underground utility loop fully accessible
for maintenance and repairs, built outside the roadways on both sides. To
implement the master plan's design would have required clearing a 235-foot wide
swath of trees about one mile long.
View of existing lake on the EPA/NIEHS site prior to construction
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
40
-------
Site plan with four-lane road
Site plan with two-lane road
The largest oak tree on site is 12 feet
in circumference.
The project team questioned the master plan requirements for the four-lane loop
road as being both extremely costly and disruptive to the natural environment.
Detailed traffic studies demonstrated that a two-lane road would be more than
adequate to handle traffic flows. Based on both the cost and negative environmental
impact of the four-lane road, the design was changed to include a two-lane road.
Electrical and communication lines were moved under the roadway, further
reducing the required clearing. Combined with land-conserving parking decks and
tight construction clearing limits, the roadway redesign required less than half the
amount of clearing, saving 25 acres of forest. The narrowed roads cost $1.6 million
less-which offset much of the cost premium for decked parking.
Preservation and Enhancement of Wetland Areas
The existing site drains into a man-made lake, with more than nine acres of wetland
areas occurring in the zone where the drainage swales meet the lake. To protect these
wetlands, a buffer zone approximately 100 feet wide was established along the lake
edge. No development was allowed in this buffer zone except for a network of
walking and jogging trails.
One exception was necessary at the site's northern edge, where the site narrows. Here,
the new loop road disturbed 0.13-acre of wetland area. To compensate for the lost
wetlands, the project team chose to enlarge a 0.024-acre wetland to almost an acre in
size. The enlargement created almost seven times more wetlands than were lost. It also
provides a "naturalist garden" for the Campus.
Specimen Tree Study
A tree survey is an important first step when designing and building on a wooded
site, however a survey alone is not sufficient. An integrated, "green" approach to
siting requires the entire project team, civil engineers as well as architects, to
consider specimen trees during the formative stages of scheme design. In this case,
the schematic design for the roadway to the EPA Campus was completed before the
tree survey was consulted, and the result was a design in which the main entry drive
for the facility would have destroyed many of the most mature trees on the site.
In the end, however, the roads were redesigned to save several large oak trees.
The preserved area now forms a natural gateway to the site and serves as a living
reminder of the homesteads that stood there in the early part of the 20th century.
The "near miss" with the oak trees had a surprising side effect, making these historic
trees a symbol to the EPA project team of the importance of designing with nature.
Water Quality
All construction sites impact their watersheds, affecting both surface and subsurface
water quality. Water contaminants from a typical building site include nutrients
from fertilizers and toxic chemicals, pesticides used on landscaped areas,
hydrocarbons from roadways and parking lots and sediment from soil erosion.
The EPA Campus has been developed to protect water quality. The man-made lake
and wetland areas on the site act as pre-existing water quality features to control
runoff and filter contaminants. These have been supplemented by a new water
quality pond and ten biofiltration sites to provide stormwater retention, sediment
collection and filtration before water is released downstream to Burden's Creek.
Even though the EPA Campus only affects a small portion of the 511-acre
watershed, the use of highly effective stormwater runoff control measures reduces
downstream impacts within the basin.
41
Design Process: Water Quality
-------
Pollution Prevention Strategies
Many of the design decisions for the new EPA Campus, contribute to improved
water quality through pollution prevention. These pollution prevention strategies
include the use of low maintenance landscaping that relies on native and adapted
species and reduces the need for fertilizers and pesticides. Incentives for carpooling
and mass transit coupled with reductions in parking will lower traffic density,
thereby reducing airborne hydrocarbon and particulate contaminants. Parking
decks, grass paving for emergency access roads, and mulch pathways for nature trails
further reduce the total amount of impervious surface and help reduce runoff. The
facility also meets all National Pollutant Discharge Elimination System (NPDES)
permitting requirements.
Erosion Control
Erosion control for the EPA Campus was designed according to North Carolina
requirements, which require measures including sediment traps and silt fences to
retain coarse sediment during construction, operations and maintenance. These
measures are essential to protect the on-site lake from sedimentation. As
enhancements to the State's mandates, additional filtration measures were added to
trap fine clay particles. During construction, an experimental gypsum treatment
process was used periodically to accelerate settling of the clay, improving the
effectiveness of the sediment ponds.
Water Pretreatment Options
Runoff from roadway and parking areas contains hydrocarbon and particulate
contaminants as well as heavy metals such as mercury. A common stormwater
treatment method is to capture these contaminants in a physical device such as an
oil-grit separator to "pre-treat" the water before it leaves the site. Oil-grit separators
were considered for the EPA Campus but ultimately not selected because other
strategies were discovered with higher contaminant removal efficiency, lower cost
and lower maintenance requirements.
The strategy preferred by the project team was one in which concentrated flows are
collected and treated in small bioretention areas. These areas are distributed around
the site in ten different locations. In the collection step, grassy swales at the edges of
paved areas are used instead of curbs and gutters to channel the water to the
bioretention areas. These swales encourage runoff to "sheet flow" over vegetated
areas, naturally filtering contaminants suspended in the runoff as the water passes
through the vegetation and percolates through the soil. Larger water quality ponds
at the northern and southern ends of the site serve as additional cleansing devices
for areas not served by bioretention ponds. These bioretention facilities and water
quality ponds were also designed as aesthetic enhancements to the site.
The realities of the site, however, required that the use of swales be balanced with
other priorities. Curbs and gutters were still used in small areas where absolutely
necessary to prevent extensive tree clearing or to control traffic.
The bioretention areas use subsurface compost and plantings to accelerate the
filtering of contaminants, while water quality ponds retain stormwater in
constructed ponds filled with wetland plantings that cleanse the water. Water quality
ponds were not selected as the primary solution because they require a larger
amount of tree clearing than the smaller bioretention areas, which can be tucked
into areas already being cleared for roadway construction. The water quality pond,
however, can accommodate a larger quantity of runoff. The pond at the south end
of the site has a storage capacity of one-half acre-feet of water (160,000 gallons).
Key Issues to Consider
Work with natural drainage
systems
Minimize the use of impervious
paved surfaces
Plan on-site stormwater
retention where natural
filtration is insufficient
Protect existing water
sources from soil erosion or
other sources of contamination
Maximize use of passive and
natural methods for treating
stormwater, such as sheet
flow across vegetated areas
and bioretention
What is an NPDES Permit?
Because sediment is recognized as
a significant pollutant that results
from construction activity, NPDES
permits are required for all
construction sites larger than
five acres in size.To comply with
permitting requirements, erosion
controls are required prior to and
during construction, and
stormwater management practices
are required after construction.
What is Non-Point Source
Water Pollution?
Any source of water pollution or
pollutants not associated with a
discrete conveyance, including
runoff from fields, forest lands,
mining, construction activity and
saltwater intrusion.
42
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
-------
Oil-Grit Separator
A three-chamber underground
structure which uses gravity to
separate the grit and oils from the
water.The grit and sediment in the
runoff settle to the bottom of the
first chamber of an oil-grit
separator. In the second chamber,
the oils rise to the top and are
trapped in the chamber by an
inverted pipe, which draws water
from the bottom of the chamber.
The third chamber then
discharges the "cleaned" runoff.
Bioretention
A depressed, heavily vegetated
area using plants and soils to
remove pollutants from
stormwater runoff.Various
physical and biological processes
including absorption, transpiration,
filtration and decomposition occur
in the root zone to improve water
quality (see Bioretention diagram).
Water Quality Pond
A permanent pool of water used
for treating stormwater runoff.
Water quality is achieved by
gravitational settling, algal settling,
wetland plant uptake and bacterial
decomposition.
JTLET STOR
FLOATING rRPm
DEBRISAND / OUTL
OILS, /
INVERTED \ r.
OUTLET \ ^
PIPE V
\- NORMAL
MAXIMUM
PONDED
WATER DEPTH
(6 INCHES)
SHEET FLOW
GROUND COVER
OR MULCH LAYER
PAVEMENT
GRASS
BUFFER
-]'_0" »
MIN.
^=!
~l
t~y
AM
6
iLMms-
- PLANTING
SOIL ^
STORM DRAIN
OUTFALL PIPE
f
1
4'-0" MIN.
1
f IN -SITU
SAND 1 -- MATERIAL-
BED . .
BIORETENTIONAREA
-I
Bioretention diagram
Landscaping
Low maintenance landscaping provides one of the most cost-effective opportunities
for sustainable design. By choosing plants tolerant of native soils, climate and water
availability, irrigation systems are simplified or eliminated and the associated
maintenance and irrigation costs are reduced.
The landscape plantings selected for the EPA Campus represent a cross section of
plants that are either native or adapted to the region, and drought tolerant. Plant health
will be maintained through the use of compost and organic mulches prepared on site.
Low-Maintenance Landscaping
The new plantings for the EPA Campus are either native species or species that can
survive the local climate, soils and water availability. This minimizes the need for
fertilizers, pesticides and irrigation. Because of this reliance on native and adapted
plantings, a "quick coupler" irrigation system has been provided as a low-cost and
appropriate alternative to a fully automatic irrigation system. The quick coupler can
be connected to hose bibs at intervals throughout the site to irrigate new plants
during their period of establishment and to assist during periods of extreme drought.
An exception to this approach was made in the main building entry plaza for
plantings in the raised planter beds. These planters provide a non-permanent
landscape that may include some "exotics." Accent plantings on the main entry
plaza will be irrigated with an automated drip irrigation system. The drip irrigation
system provides a highly water-efficient solution for these small, localized areas
which will require irrigation.
Grasses and Wildflowers
Instead of using traditional turf grass, the 15 acres of land along the road will be
planted with wildflowers and native warm season grasses. These wildflowers and
grasses are available in five palettes of color and species. A detailed wildflower
specification identifies species and quantities of seed for each palette, with a
schedule that will establish a permanent colony over a three-year period. The
specification includes seeding directions for spring and fall plantings,
environmentally acceptable herbicides and biodegradable soil retention blankets.
This low-maintenance alternative will add diversity and attract wildlife while
requiring mowing with a "bush hog" only once a year to control woody vegetation.
43
Design Process: Landscaping
-------
Wetland Plantings
A total of 0.154 acres of wetland area will be disturbed by construction: 0.13 acres
from an unavoidable road cut and 0.024 acres when wetland area is converted into a
larger wetland pond. When complete, the new pond plus the remediated wetland
areas will comprise almost an acre of new wetlands. Once the wetland pond has been
established, an underground transfer pipe will allow water to flow to the lake and
back, controlling water levels in the pond. It is anticipated that the pond will need
minimal annual maintenance to control forest succession and weedy overgrowth.
Just as the undisturbed forested knoll at the center of the entry drive creates a public
identity for the facility, the wetland pond on the lake side of the site will form a
human-scaled, private sanctuary. The small pond with a naturalist garden of wetland
plantings will underscore the value of wetland environments.
Composting
Plant health can be greatly improved by the use of compost and organic mulches.
The project team made plans to incorporate these resources throughout the life of
the facility.
The specifications stipulated that
during construction, land that required
clearing would first be logged for
valuable timber, and then the
remaining debris would be shredded
in a tub grinder to create mulch for
future use on the site. This is in
contrast to the prevailing practices in
this region, where it is typical for
landscape scrap to be piled high and
burned. Mulch stockpiled on site has
been aged for use in finish landscaping.
Some of the mulch has been mixed
Key Issues to Consider
Select plantings with minimal
irrigation, fertilization and
pesticide needs
Plant native species
Protect and enhance wildlife
habitat
Compost food waste and
landscaping debris on site
Consider alternatives to turf
grass where appropriate
Representative Plant Mix
Wildf lowers
Black-eyed Susan, Purple
Coneflower, California Ox-eye
Daisy,Yellow Cosmos, Toadflax,
Cosmos, California Poppy,
Tickseed, Moss Verbena,
Perennial Lupine
Tall Grasses
Indian Grass, Little Bluestem
Purpletop, Sideoats Grama,
Blue Grama
Wetland Plantings
Arrow Arum, Lizard Tail, Tussock
Sedge, Sweetflag, Blue Flag Iris
Wetland Meadow Plantings
Broomsedge, New York Aster,
Switch Grass, Little Blue Stem
Wildflowers attract wildlife
Wetland plants
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
44
-------
Benefits of Composting
Transportation of organic
waste from landscaping and
food preparation of the site is
eliminated or minimized
Biodegradable waste is not
stored in landfills, where it
would be mixed with
inorganic and often toxic
wastes and prevented from
biodegrading
A renewable source of
organic fertilizer for
landscaping is created on site
Plant fertilizers need not be
transported to the site
Key Issues to Consider
Optimize building insulation
Optimize building glazing
Incorporate exterior shading
and sun control
Evaluate impact of interior
sunshading
Minimize air infiltration
Provide adequate air barrier
and vapor retarder
Minimize unintentional or
uncontrolled thermal bridges
Use light-colored roofing
directly into the topsoil, where the decomposed material will aerate and amend
the soil for more productive plant growth. Cafeteria waste at the Campus is also
composted and used for landscaping on site.
Building Envelope
Improvements to the building envelope typically provide the first line of defense in
energy-efficient design strategies. Sunshading, insulation, a tight building envelope
that limits infiltration and thermal bridging, and high performance glass all reduce
unwanted heat gain or loss. "Optimizing" the design of the building envelope refers
to a process that systematically evaluates options to find the best combination of
strategies that will cost-effectively improve performance.
Evaluation of Building Loads
Before energy design strategies can be explored, an understanding of the building's
most significant energy requirements should be developed. Major components of
the EPA facility energy load were ranked by building type (see accompanying pie
charts). These components included outside air for ventilation, internal loads
generated by occupants, lights and equipment; energy for supply air fans; and
heat loss and gain through the building envelope.
These initial load profiles guided the
project team as they sought design
strategies with the greatest benefit. For the
new EPA Campus, high ventilation
requirements in the laboratories, and high
internal loads in the offices lessen the
relative impact of the building envelope on
overall energy use. The relative importance
of the building envelope in terms of overall
energy use is also much greater for the
office buildings than for the laboratory
buildings. For example, office buildings
attribute 23 percent of peak energy load to
the building envelope and the labs only
attribute 2 percent. This indicates that
improvements in the building envelope of
the office building will be more cost-
effective than improvements in the
building envelope of the lab buildings.
EPA CAMPUS COMPONENT PEAK LOADS
LABORATORY
Total Load 64 MillionBtu/Hr
supply fan
indoor
13%
77%
OFFICE
Total Load 18 Million Btu/Hr
Sun Control
A key goal of sun control is to provide
beneficial daylighting for building
occupants while blocking unwanted glare
and heat gain. The facility's facades
incorporate some architectural sunshading
through the deep profile of the precast
concrete cladding. Clusters of tall trees,
some as high as 80 feet, which were
preserved during site design, also provide
valuable shading for the west side of the
low three-story office buildings. Low-E
glazing and interior mini-blinds complete
the sun control strategy in office areas.
supply fan
envelope
23%
45
Design Process: Building Envelope
-------
Motorized shadecloth blinds are used in public areas in the central office tower.
However, the lab buildings do not require interior blinds because all of the occupied
spaces are inboard and the deep articulation of the precast concrete outer walls help
shade strong midday sun. The cafeteria and training area facades, with 12-foot-high
floor-to-ceiling glass overlooking the lake, incorporate a deep architectural trellis
planted with deciduous vines that provide maximum sunshading in summer and
partial sunshading in winter.
Glass Selection
The performance of types of glazing varies tremendously. Compared to most tinted
and reflective glazings, spectrally selective Low-E coatings provide a higher level of
daylight for a given amount of solar heat reduction. This feature is especially
important in cooling-dominated climates. The Comparison of Glazing Performance
(below) indicates that the improved Low-E double glazed insulating unit with
spectrally selective glass has the highest Coolness Index (CI) of all. This ability to
transmit light without heat is a major technological achievement. For the EPA
facility, the improved Low-E is used on southern and western exposures and the
atrium roof. Standard Low-E is a lower cost option and provides sufficient
performance for the northern and eastern exposures.
Comparison of Glazing Performance Glazing types used at EPA
Glazing Type | U-Value | Shading | Visible Light | Coolness
(winter/summer) Coefficient Transmittance Index (CI)
Comparative Performance
of Glazing Types
Heat Flow
U-value = 1.11
This is the
comparison for
other glazings ^^^^^L
Solar Heat ^^
SHGC = 0.86 I^^^J
1 4% of solar
radiation is
rejected
Daylight
VT = 0.90
10% of visible
- 86% of
^i solar
^^ radiation is
transmitted
90% of
visible light is
light is reflected >h transmitted
or absorbed
Heat Flow
U-value = 0.24
88% less heat ^f
than single-pane
clear glazing ^ ^^^m
Solar Heat ^.^
SHGC = 0.41 ^^^_
59% of solar
radiation is f^^F
rejected
Daylight
VT = 0.72
28% of visible
light is reflected
1^^ 41% of
^^fr solar
radiation is
transmitted
72% of
visible light is
transmitted
or absorbed
C' I I I It- \ _|
Single pane clear glass (top) and
Single pane clear glazing 1.09/1.03 0.94 89%
Double pane clear glazing 0.48/0.55 0.81 79%
.94
.97
double pane glass with spectrally
selective low-E coating (bottom)
Bronze tint on clear double 0.44/0.52
pane glazing
Low-E coating on clear 0.31/0.32
double pane glazing
Low-E coating on green spectrally 0.31/0.33
selective double pane glazing '
Improved Low-E coating on 0.29/0.30
green spectrally selective double
pane glazing
Heat Mirror 88 1" insulating 0.32/0.37
unit with green glazing 2i3
Heat Mirror 44 1" insulating 0.31/0.35
unit with green glazing 2i3
Super Windows
0.13
0.29
.59
0.47
0.35
0.44
0.24
0.36
18%
73%
63%
60%
61%
32%
54%
.62
1.24
1.34
1.71
1.38
1.33
1.5
1 Spectrally selective glass has different performance depending on the color.
2 Performance will vary depending on the film used, heavier films reduce light transmittance
and lower shading coefficient, but U-value remains about the same, HM88 and HM 44 are
shown to demonstrate some of the range.
3 Assumes 1" insulating unit, 1 1/2" insulating unit will have a U-value of 0.23/0.27 for HM88
and 0.21/0.24 for HM44.
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
46
-------
Building Envelope
Refers to a building's exterior skin.
Particularly important is the
extent to which it allows or
resists the passage of air, light,
heat, moisture, sound and pests
into and out of the building.
Coolness Index (Cl)
Sometimes referred to as efficacy
(ke), this is the ratio of visible light
transmittance to shading
coefficient; a higher number
indicates better admission of
daylight with less accompanying
heat gain.
Low-E
Low-emissivity, a term used by the
glass industry for microscopically
thin metal or metallic oxide layers
deposited on a window or skylight
glazing surface primarily to reduce
the U-factor by suppressing
radiative heat flow. A typical type
of low-E coating is transparent to
the solar spectrum (visible light
and short-wave infrared radiation)
and reflective of long-wave
infrared radiation.
R-Value
A measurement of the resistance
of a material to the transfer of
heat. Insulation having high R-value
is important for walls, roofing and
foundations. Windows and doors
may have improved R-values
depending upon their design.
Shading Coefficient
measures the total solar heat gain
through the glazing compared to
1/8" clear glass under the same
design conditions; the lower the
shading coefficient, the lower the
solar heat gain.
Thermally Broken Windows
The largest disadvantage of aluminum as a window frame material is in its high thermal
conductance. Unless "thermally broken," the frame readily conducts heat, greatly
raising the overall U-factor of a window unit. Moisture accumulation in the building
can also become a problem if it becomes cold enough outside to condense moisture or
frost on the inside surfaces of window frames. Consequently, all aluminum window
frames for the EPA Campus are fully thermally broken. This feature will not only
improve comfort, but it will also eliminate condensation that could lead to the growth
of molds and mildew, thus preserving good indoor air quality.
Light shelves at National Computer Center
Light Shelves
Metal light shelves that would also act as a sun screening element were explored during
design. While light shelves can enhance the use of daylight in office areas, the potential
benefits for the EPA offices were limited because of the high proportion of interior
closed offices. In addition, deep window ledges and the tall existing trees adjacent to
the building already provide some sunshading. Consequently, at a cost of approximately
$500,000, light shelves were determined not to be the most cost-effective way to
improve performance. Instead, improved low-E glazing was used on the west and south
facades for a premium of $10,000. The result was almost as good as the $500,000
solution and was much more cost-effective.
Insulation
Due to North Carolina's mild climate and the relatively small contribution of the
building envelope to overall thermal loads, super-insulation is not a cost-justifiable
strategy in the new facility. Even in the winter, the office buildings will be in cooling
mode most of the time, and the lab buildings will be minimally affected by their
insulative value. Due to the internal loads generated by people, lights and computer
equipment, offices on the interior are cooled virtually year round. In a typical office
building, the envelope is 15-20 percent of the load, whereas the lights, equipment,
people and outdoor air constitute the remainder of the load. In summer, light-colored
roofing and cladding will contribute to heat gain reduction, putting less of a burden
on the insulation to slow heat transmission. Therefore, insulation for the facility is
provided in moderate quantities: U-values of 0.05 for the roof and 0.07 for the walls.
47
Design Process: Building Envelope
-------
Infiltration
The infiltration of outdoor air can be a major source of heat transfer through a
building's envelope. It can also introduce unwanted moisture into the building's
interior. The EPA Campus used low-toxicity, high performance caulks and sealants
to minimize unwanted heat loss and heat gain, to maintain required pressurization
relationships between office and lab, and to prevent infiltration of exhaust air or
ground contaminants. Air locks are provided at all public entries.
Albedo Control
Roof and exterior wall surfaces that reflect rather than absorb light limit heat
absorption through the building envelope. The measure of light reflectivity is called
"albedo." Generally, materials with high albedo are light in color. Consequently, the
project team chose white single-ply roofing (albedo of 0.78) throughout the facility
to limit heat gain, and reduce air conditioning requirements. With an "emissivity"
of 0.90, this roofing will also shed it's absorbed heat relatively quickly. Even though
studies show that similar white roofs lose up to 25 percent of their albedo within
the first three years following installation due to dirt accumulation, the performance
stabilizes at a level of about 0.60 albedo, which is still significantly better than
typical black-roof surfaces.
The building cladding is a light beige precast concrete, with beige concrete masonry
units at the building base and cores. These light-colored surfaces will also contribute
to reduced cooling requirements for the facility.
Albedo and Emissivity of Materials
Material
Concrete
Tar paper
Bright galvanized iron
Bright aluminum
Aluminum Paint
White single ply roofing
Black EPDM roofing
Gravel
| Albedo
0.3
0.05
0.35
0.85
0.80
0.78
0.045
0.72
| Emissivity
0.94
0.93
0.13
0.04
0.27 - 0.67
0.90
0.88
0.28
Source:The Protocols of White Roofing by James I.Seeley,
published in The Concrete Specifier, November 1997
Operable Windows
Air pressure relationships within the facility control the flow of air between the lab
and the office portions of the building. These pressure relationships enhance safety
within the building by ensuring that air in laboratory areas cannot migrate into
office areas, which are under positive pressure. The pressure relationships also keep
odors and fumes from spaces such as loading areas, trash docks and print rooms out
Thermal Break
To solve the heat conduction
problem of aluminum frames, the
frame is split into interior and
exterior pieces and a less
conductive material such as plastic
is used to join them. Current
technology with standard thermal
breaks has improved aluminum
frame U-factors from roughly 2.0
to about 1.0.
U-Value
A measure of heat flow is the
inverse of R-value (R=1/U).
Albedo
A measure of the light reflectance
of a material, whether a building
material, paving, ground cover, etc.
Building materials with high
albedo (lighter colors) reflect
more light off their surface and
reduce the overall heat gain
through the building's envelope.
Emissivity
The rate at which absorbed
energy is radiated away from an
object; a desirable roofing
membrane will easily release its
absorbed heat energy and keep
the roof cooler.
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
48
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of the airstream. Operable windows would compromise the EPA's facility's pressure
balance, and could create indoor air quality problems due to the region's high
humidity and heavy mold and pollen loads.
However, to help bring fresh air inside during good weather, an outside air
economizer system has been integrated into the design. When outside temperatures
permit, and humidity is not too high, the outside air economizer system provides
cooling with up to 100% outside air, filtered to remove dust, pollen and mold spores.
Key Issues to Consider
Develop flexible space plans
using modular design that
anticipates future needs
Develop mechanical, electrical
and plumbing infrastructure
that anticipates future needs
and can accommodate change
Improve efficiency of the
building through the use of
shared spaces
Space Planning
Space planning has a significant impact on the overall environmental performance
of most facilities. Depending on how the space is designed, it will either become
obsolete after a short period of time and require complete renovation, or it will be
flexible enough to meet future needs with a minimum of effort. Consequently,
increased flexibility enhances building longevity, thereby conserving material
resources and reducing waste streams.
The new facility has been developed with a flexible organizational system to
accommodate movement of personnel, changes in research programs and changes
in the mix of labs and offices.
Modular Office Design
To minimize the demand for office alterations, the design accommodates a limited
number of office sizes. Two basic sizes are provided for closed offices, and two sizes
for open workstations. The fundamental building block for office planning is a 36-
by-50-foot "pod" with fixed demising walls that separate one pod, or suite, from the
next. While this pod can accommodate open and closed offices in several different
ways, a 20-foot-wide zone along the windows is always dedicated for open
workstations so that people in the interior zone of the office floors will have access
to natural light.
When reconfiguration is necessary, the perimeter suite walls, lights, sprinklers,
ceiling grid and electronic sensors can usually remain in place. Construction is
mostly limited to those partition walls within the pod that must be changed to
accommodate a different proportion of closed to open, or large to small offices.
Demountable partitions were considered but not chosen because the need for
reconfiguration within the office areas will not be frequent enough to justify the
additional investment.
U
n-
A Q"
^ C\
I .11. I J I
Standard office suite configuration
49
Design Process: Space Planning
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Modular Lab Design
The laboratory space is designed to provide safe and efficient layouts with easy
access to utility services and investigator offices. A service corridor provides access
to essential plumbing, exhaust risers, electrical panels and bottled gases. The
telecommunications backbone bisects each floor plate. Modular lab "building
blocks" measuring 11 feet by 23 feet are arrayed to each side of the service corridor,
and an adjacent 11-foot by 12-foot support/office block provides added flexibility
to house science or scientists. A service ledge containing all lab support utilities
provides the core element for multi-module peninsula benches or the base structure
for utility free dividing walls. Modules can be easily combined by leaving out these
wall segments (up to eight modules in width), or by extending the base module to
33 feet by using the lab support module. Conversely, adding a wall atop a peninsula
bench allows easy division of larger labs into smaller labs without disrupting
electrical or piped utilities.
Bracing
Wall or strut/shelves
Electrical
Air/Vacuum, Gases
Plumbing
Service Ledge
with Utilities
I
c
=
o °
w
o °
o
Bolt-on
Casework
Service Corridor
Typical Laboratory Plan
Utility distribution to lab benches is provided through the fixed service ledge
which supports and protects all utility piping. Services include gas, compressed
air, vacuum, water and electricity for various kinds of specialty equipment and
instrumentation. Since utility lines do not normally need to be moved when labs
are reconfigured, there is less disruption, costs are minimized and demolition waste
is drastically reduced.
Lab casework and counter tops are designed in three- or four-foot units, each with
pullout writing boards and either high or low bench heights. Kneehole spaces
feature lockable computer keyboard drawers, and wall cabinets and open-wire shelf
units are fully adjustable. This allows ready reuse of laboratory casework over the
years of occupancy. The EPA labs have been developed so that all changes, except
those that affect the size of the lab, can be made without construction. When
construction is required it is limited to gypsum partitions between labs, while the
floor, ceiling, lighting, sprinklers, diffusers and lab services all remain intact.
These conserving strategies greatly extend the service life of labs and equipment,
and reduce the quantity of lab furnishings and building materials typically hauled to
landfills. Waste from future renovations is limited to gypsum wall board and steel
framing, both of which are fully recyclable. Finally, very little research time will be
lost waiting for renovations to be completed.
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
50
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Key Issues to Consider
Minimize the building's
exterior perimeter by
connecting otherwise
separate buildings
Draw natural light into the
building interior, but avoid
over-lighting
Minimize heat gain and heat
loss through the atrium roof/
skylight
Section through the
central atrium
Building Atrium
Building atria can enhance the functionality of a building by providing large enclosed
spaces that contribute to the sense of community within a facility. The atrium for
the new EPA facility was seen as an important strategy to encourage interaction
between EPA employees, not just within work groups but across disciplines. When
properly designed, atria can also serve as energy conservation features that reduce
heat gain and loss while bringing natural light into a building. However, careful
skylight design is necessary if the potential energy benefit is going to be realized. If
designed without proper care, an atrium can trap solar heat in the summer and lose
heat through the skylight in the winter, greatly increasing energy usage.
Building Massing
The building massing of the EPA Campus has been developed to reduce exterior
surface area while addressing the desire for a predominantly low-rise facility. A series
of building atria connect laboratory and office buildings, to bring daylight into the
facility while providing a main street of circulation for the complex of buildings.
From a design perspective, the atria connect two otherwise separate buildings,
reducing the exterior perimeter by exchanging skylight area for what would
otherwise be exterior vertical walls. The connection provides savings, both in
capital costs and energy costs.
Energy and Daylighting Analysis
The goal for atrium skylighting is to meet required functional and aesthetic
requirements while balancing daylighting and energy goals. To optimize the design
of the atrium skylight, the project team used energy and daylighting analysis to
assess heat gain and loss through the atrium skylight, illumination requirements that
could be met with daylighting, and heat gain associated with electric lighting.
The original atrium design called for a top-of-the-line, all-glass skylight, with high-
performance low-E glazing. However, the project team quickly realized that this
approach was problematic. The atrium skylight would have provided too much
light. The light converts to heat energy inside the building, which impacts the
overall building cooling load. Excessive lighting also causes visual discomfort from
harsh levels of contrast. However, simply lowering the visible light transmittance of
the glass would have resulted in a gloomy, gray sky appearance, with high levels of
interior reflectance on the glass.
After adjusting model parameters for six different atrium roof options, the optimum
skylight design was selected. Using the same high performance glass for
approximately 26 percent of the surface, the remainder of the atrium surface was
comprised of translucent panels with improved insulative value, and opaque panels
filled with insulation. The revised design reduces the atrium's peak energy usage by
two-thirds compared to the all-glass skylight. The solution still provides plenty of
light, so that the perimeter of offices facing the atrium will require very little
artificial lighting.
It is difficult to calculate the net benefit of the new facility's atrium without a
detailed energy analysis of a similar scheme with no atrium. For comparison
purposes, the office portions of the adjacent central office tower next to the entry
plaza were determined to operate on the same schedules and at the same density as
the office buildings connected by the atrium. Energy calculations indicate the office
buildings fronting the atrium use 37,400 Btu/SF/Yr versus 41,000 Btu/SF/Yr for
the freestanding tower, a 10% reduction in energy consumption. This reduction is
primarily related to decreased exterior surface.
51
Design Process: Building Atrium
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Atrium Skylight Options
Multiple skylight options for the
EPA project were considered
(see diagram). A comparison of
the first cost and the energy cost
over a 20-year life cycle was
provided for each. Schemes one
and two were eliminated due to
their relatively high cost and
comparatively low energy
performance. Schemes three,
four and five had remarkably
similar cost and energy
performance.
Scheme three is a modified
version of the original skylight
that faces west. In contrast,
schemes four and five introduce
a series of clerestory windows
that face north and south, a
traditionally-preferred approach
for passive solar design that
eliminates the western exposure.
The energy analysis showed a
surprisingly small added energy
benefit for schemes four and five. Scheme three was ultimately chosen because it
would be easier to maintain, due to its single, continuous slope as opposed to
multiple peaks and valleys. Scheme three also allowed a clear view of the sky from
the interior.
Central atrium
Illllllll
Atrium skylight options
COST
$1,000,000
$900,000
$800,000
$700,000
$600,000
$500,000
$400,000
$300,000
$200,000
$100,000
$0
Total Cost
First Cost
Energy Cost
Base Scheme Scheme Scheme Scheme Scheme
Case I 2 3 4 5
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52
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Key Issues to Consider
Maximize the benefits of
natural daylight
Select high-efficiency, long-
lasting light sources and high-
efficiency fixtures
Make use of task lighting
Balance lighting efficiency with
visual comfort
Control the balance between
natural and artificial lighting
with sensors and dimmers
where appropriate
Ambient Light
The overall lighting level of a
space, including primarily daylight
and overhead lighting.
Ballast
A device used to operate
fluorescent and HID lamps. It
provides the necessary starting
voltage, while limiting and
regulating the lamp current during
operation.
Color Rendering Index (CRI)
A scale of the effect of a light
source on the color appearance of
an object compared to its color
appearance under a reference light
source (low numbers indicate
unnatural appearance; 100
indicates no color shift).
Compact Fluorescent Lamps
(CFLs)
Fluorescent lamps that are
configured to fit into a standard
incandescent socket. Many models
contain an integral ballast.
Dimming Systems
Controls that automatically turn
down the artificial lighting in areas
that receive sunlight during the
daylight hours to save electricity
and reduce the building's
cooling load.
The outcome of this rigorous analysis was the selection of an atrium skylight design
with reduced construction cost, combined with excellent daylighting and thermal
performance. In addition to the energy and cost benefits, the atrium design
contributes to the aesthetic quality, with a forest-like mix of brightness and shade,
intermingled with views of the sky.
Lighting Systems
When electricity use and the increased cooling load due to electrical lighting are
considered together, electric lighting generally represents approximately 15 percent
of the overall energy consumption in typical office buildings. Efficient lighting
requires appropriate use of daylight, an accurate assessment of required lighting
quantities, use of efficient lamps, ballasts and fixtures, and measures to reduce
unnecessary lighting during unoccupied hours. For the EPA Campus, the
combination of sensor controls and high-efficiency fixtures produced lighting that
is approximately 70% more efficient than a standard code-compliant building.
Besides the energy issues associated with electric lighting, there are quality of life
and productivity issues to consider. Excessive illumination can create visual
discomfort, glare, headaches and fatigue while increasing energy consumption and
associated pollutant emissions. Greater use of daylighting, reduced glare, good color
rendition, elimination of lamp flicker and correct lighting levels can contribute to
the productivity and well being of a building's occupants.
Green Lights
EPA's voluntary Green Lights program encourages companies to upgrade their
lighting. While the efficient lighting technologies have a higher first cost, their
payback periods are quick. Participants in the Green Lights program have found
that, on average, their lighting improvements have generated a 30 percent rate of
return. Although originally intended for existing buildings, the Green Light
principles are equally valid for new construction. Consequently, the project team for
the EPA Campus implemented the full range of measures described in the Green
Lights program, including high-efficiency lamps and ballasts, task lighting,
photoelectric dimming controls, occupancy sensors, a central lighting control system
and bulb maintenance. The combination of sensor controls and high-efficiency
fixtures produced lighting for the new Campus that is about 70% more efficient
than standard code-compliant buildings.
Daylighting
The EPA Campus design promotes the use of daylighting in a number of ways. The
building atria that connect lab and office buildings bring daylight into the building
interior. All exterior glazing has high visible light transmittance and a low shading
coefficient to provide "cool light." Interior space planning supports daylighting
through the use of light color finishes, low partition heights and a planning concept
that designates almost 50 percent of the perimeter space planning zone to be
dedicated to open office workstations. This zone keeps exterior windows
unobstructed so that light can penetrate interior office zones.
Task Lighting
Task lighting directs light onto a work surface or object that requires illumination.
This allows the general or "ambient" lighting levels to be reduced to a more
comfortable level. Ambient lighting levels for the EPA Campus were reduced in
anticipation of task lighting which will be used in all office and lab areas. The office
areas are designed to 30-40 Foot Candles (FC) ambient and 50 FC task, and the
labs are designed to 70-80 FC ambient and 100 FC task.
53
Design Process: Lighting Systems
-------
Laboratory Lighting
The laboratories for the EPA Campus are lit with direct and indirect lighting that
is complemented by task lighting on the work surface. Numerous options were
evaluated. The direct/indirect lighting scheme proved to be considerably more
efficient than a traditional scheme using down lighting alone. It also provides better
quality lighting. The indirect component enhances the spread of light while the
direct component improves overall efficiency as well as depth perception.
The direct/indirect scheme also reduces the connected watts per square foot (SF)
from 1.85 to 1.38 when compared to the direct lighting scheme alone. This is
because only one row of three-lamp fixtures is required instead of two rows of two-
lamp fixtures. This scheme also generates first cost savings. Light distribution studies
developed for the selected indirect/direct scheme demonstrate that the spread of
light in the labs will provide the desired quality.
Direct lighting
Illuminates a surface or space
directly from the light source,
whereas indirect lighting reflects
the light off other surfaces.
Downlight
A type of ceiling luminaire, usually
fully recessed, where most of the
light is directed downward.
Fluorescent
A lamp that produces visible light
by emitting electromagnetic
radiation and is much more
efficient than incandescent,
requiring only 15-30% of the
energy to produce an equivalent
amount of light.
Computer-generated radiosity study of typical laboratory
Office Lighting
In the office areas, indirect lighting proved to be less efficient and more expensive
than direct lighting. This was due to the high proportion of closed offices required
in these areas. Consequently, office areas for the EPA Campus are lit with two-foot
by four-foot recessed fluorescent downlights with compact fluorescent downlights in
the circulation zones. Even so, this scheme requires less than one connected watt per
SF. Daylight dimming and occupancy sensors in the office areas further reduce
lighting requirements, so that the anticipated energy use for lighting is only about
0.6 watts per SF.
Special Spaces
The lobby, cafeteria, conference center and breakout spaces in the atria are areas that
traditionally would receive some incandescent lighting. However, with the advent of
improved fluorescent lamps with high color rendering indexes (CRI) and no flicker,
this preference is no longer valid. The EPA Campus uses compact fluorescent
fixtures supplemented with metal halide fixtures in public areas where a stronger,
more intense source is desired.
Typical laboratory section with
direct / indirect lighting
supplemented by task lighting
Typical laboratory section with
direct lighting supplemented by
task lighting
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
54
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Occupancy Sensor
A control device that turns lights
off after the space has become
unoccupied.
Photocell
A light sensing device used to
control luminaires and dimmers in
response to detected light levels,
saving electricity when daylight is
sufficient.
Task Lighting
Any form of light that is focused
on a specific surface or object. It
is intended to provide high-quality,
flexible, lighting for a
predetermined activity.
Exit Signs
There are more than 100
million exit signs in buildings
throughout the United States,
operating 24 hours a day, 365
days a year
Cumulatively, we spend about
$1 billion per year just to
operate all the exit signs in
buildings in the U.S.
Beginning in the year 2000,
companies could save 800
million kilowatts of electricity
per year through the use of
EPA Energy Star compliant
exit signs, a total of almost
$70 million each year
A typical long-life incandescent
exit sign consumes 40 watts
and must have the lamps
replaced every eight months
A typical compact fluorescent
exit sign consumes 10 watts
and must have the lamps
replaced every 1.7 years
A typical Light Emitting Diode
(LED) exit sign consumes less
than 5 watts and has a life
expectancy of more than 80
years. (An LED is a solid state
light source with no filament)
Source: Energy Efficient Lighting
Association, 1998
Central atrium
Lighting Controls
Many types of automated control systems have been developed to reduce the
use of electric lighting when it is not needed. These systems include a variety of
photoelectric sensors for dimming in response to daylight, occupancy sensors that
shut lights off when occupants leave the room, and time clock controls that shut
lights off based on occupancy schedules. Lumen maintenance controls use dimming
to undo the overlighting that is typically employed to compensate for degradation
of lamp output over time.
The EPA Campus uses several of these systems in its lighting strategy. Photoelectric
sensors for daylight dimming control are used in the building atria, the cafeteria and
conferencing center, and in office building perimeter zones, including office areas
that face the atria. Photoelectric sensors are also used to control lighting in the
parking garages. Occupancy sensors are used to control lighting in open and closed
office areas, as well as support areas such as storage rooms, copy rooms and small
conference rooms. However, occupancy sensors will not be used in labs for safety
reasons. The Building Automated Control System also has a timeclock feature that
will switch off lights inadvertently left on during off hours.
Exit Signs
Although exit signs are a seemingly minor concern, they are plentiful in buildings
and are illuminated 24 hours a day, seven days a week. When relamping is
considered, the differences between available options are magnified. For example, a
typical long-life incandescent lamp in an exit sign must be replaced every eight
months versus 1.7 years for a compact fluorescent, and 80 years for a Light
Emitting Diode (LED) exit sign. To take advantage of the installation, operations
and maintenance dividends, the EPA Campus uses LED exit signs throughout.
Building Mechanical Systems
Building mechanical systems that provide heating, cooling and ventilation generally
account for as much as 50 percent of a typical building's total energy consumption.
The efficiency of systems, however, varies considerably-as does the potential
environmental impact. This impact can include resource depletion and habitat
55
Design Process: Building Mechanical Systems
-------
destruction from the extraction of fuel, air emissions from combustion that create
pollution and contribute to global warming, and ozone depletion from the release of
chlorofluorocarbon (CFC) and hydrochlorofluorocarbon (HCFC) refrigerants in
cooling equipment.
From both a cost and a pollution prevention perspective, investments in energy-
efficient systems should be considered after all efforts have been made to eliminate
unnecessary thermal loads. Energy conservation and energy efficiency strategies for
the EPA Campus netted more than a 40 percent reduction in energy consumption
for the overall facility, compared to average building energy performance statistics
developed by the U.S. Department of Energy.
Energy Modeling
Energy modeling is an effective tool that allowed the project team to evaluate
options and find cost-effective solutions. An energy budget was developed for the
EPA Campus, providing modeling information on peak loading and operational
energy use. While reductions in peak loading can lead to first-cost savings as systems
are downsized, operational energy use must also be evaluated as an indicator of
ultimate energy consumption. Producing an energy budget during the detailed
design phase allows for an accurate simulation because systems have already been
selected. However, it limits the ability of designers to make use of energy studies to
inform system selection and architectural scheme design. Ideally, a preliminary
energy budget should be developed in schematic design and used as a design tool,
then updated during design development and final design phases.
Central Utility Plant
The EPA Campus shares a central utility plant with the National Institute of
Environmental Health Sciences (NIEHS) facility across the lake. A separate utility
plant for the EPA facility was originally considered because the elimination of the
36" chilled water (CW) and 14" high temperature hot water (HTHW) campus loop
would have considerable first- cost savings and limit thermal transport losses.
However, the use of a central plant has the advantage of scale that favors the use of
high-efficiency equipment, shared operations, staff and equipment, redundancy and
load balancing. The shared plant was ultimately endorsed and, in the current design,
cross-connected underground pipes supply HTHW and CW to both the EPA facility
and NIEHS.
In addition to shared equipment redundancy with NIEHS that offset some of the first-
cost premium, the EPA Campus gained operational benefits associated with shared
plant personnel. This shared redundancy proved to be a major cost and environmental
savings to both EPA and NIEHS. One 3,500-ton chiller and one 40-million Btu/hour
boiler were cut from the project, which eliminated the purchase, production and
transport of enormous pieces of equipment. With less room needed for equipment, the
central plant building expansion was reduced by 5,000 square feet.
High Efficiency Chillers and Boilers
The efficiency of chillers and boilers can vary considerably. However, even with
high-efficiency equipment, chiller and boiler efficiencies are not fixed. Efficiencies
can vary according to loading with some machines reaching peak efficiency at full
load and others at partial load. Consequently, a good understanding of anticipated
actual loadings, not just peak loading, is important for design so that the full load
and the partial-load efficiencies of equipment can be evaluated and optimized
relative to demand.
Key Issues to Consider
Consider the primary fuel or
energy source to be used
Look for equipment that does
not use CFCs or HCFCs
Choose high-efficiency heating
and cooling equipment, pumps
and motors
Minimize reheating of
conditioned air
Use variable frequency drives
for fans and pumps, and
variable air volume boxes for
air handling
Explore heat reclamation.
Optimize distribution of
mechanical equipment to
minimize transport losses
Consider setting goals that
exceed federal benchmarks
for efficiency
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56
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Heat Recovery System
Any system that recovers waste
heat generated by building
operation to satisfy part of the
building's energy needs. Sources of
heat include exhaust air, machines,
lights, process energy and people.
Variable Air Volume (VAV)
A feature in a mechanical space
heating/cooling system that uses
an automatic control to adjust the
air volume flow rate rather than
adjusting the air temperature.
Variable Speed Drive
A device used to control the
speed of an alternating current-
driven motor by electronically
varying the input voltage and
motor frequency.
The chillers and the boilers specified for the NIEHS/EPA Central Utility Plant
(CUP) are highly efficient units designed to operate at multiple settings. This allows
their output efficiency to be optimized. For example, the CUP chillers consume
0.54 KW/ton at 50 to 75% loads. At 100% load, consumption increases to 0.63
KW/ton, and at only 25% load, the energy consumption is an even higher 0.77
KW/ton. In other words, extremely high or low loads are the least efficient
operating modes. Because the design is based on multiple chillers in operation with
a redundant chiller provided, 100 percent output will never be required and 25
percent loading will be minimized.
Variable Air Volume
Variable air volume (VAV) systems control temperature by varying the quantity
of supply air based on the actual cooling required. VAV boxes can be set so that
minimum outdoor air requirements are met while varying the supply air to suit the
heating or cooling load in the space. In this situation, a variable speed drive on the
air handler will slow down the fan, maintaining minimum system pressure and saving
fan energy. In addition, the lower airflow passing across the cooling coil reduces the
required heat transfer in the coil as well as the amount of chilled water used.
The EPA facility uses a non-powered VAV system in the office buildings and a dual-
setting constant volume system in the laboratories. The straight system was used
instead of a fan-powered VAV even though a fan-powered VAV can contribute to
better air movement and air mixing within the office space. The straight system was
selected because the fan-powered VAV is a high maintenance piece of equipment
that consumes fan energy. The simpler "straight" system is a low energy alternative,
and it also allowed EPA to specify an increased minimum airflow. The EPA facility
provides a minimum of 2.25 air changes per hour (ACH) of outdoor air, which
exceeds the one ACH minimum recommended by the American Society of Heating
and Refrigeration Engineers (ASHRAE) 62-89.
Outside Air Economizer Cycle
Each of the air handling units for the offices and the labs at the EPA Campus is
equipped with an outside air economizer cycle with enthalpy controllers to sense
relative humidity and protect the building from overly humid air. Outside air
economizer cycle operation (also known as "free cooling") allows the air handling unit
to operate at up to a 100 percent outdoor air mode when the outdoor temperature
and humidity allows. It is the mechanical equivalent of the open window.
Economizers become active when outdoor air temperature is at or below 55 degrees.
If the outdoor temperature continues to drop below the supply air temperature (55
degrees), the system mixes outdoor air and return air to maintain temperature.
Economizer cycles create tremendous savings in climates that are mild much of the
year and where humidity is not too high. Outdoor air economizers need to be
addressed in the early stages of design because space for larger ductwork and
shaftways is required.
Variable Frequency Drives
A variable frequency drive is a solid-state device hooked to the starter of a motor,
fan or pump to allow for the motor speed to be varied according to the demand.
This allows the system to take advantage of the slower speeds and to reduce
energy consumption.
The EPA Campus uses variable speed drives on all water pumps and air handling
units. Sensors in the piping system and the duct system monitor fluctuations in the
static pressure or the water pressure, transmitting a signal to the variable speed drives
to slow down or increase the speed of the motor depending on the conditions.
57
Design Process: Building Mechanical Systems
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High Efficiency Motors and Fans
The heart of the HVAC system is the fan that pushes the air; the fan is required
whether the process requires cooling, heating, ventilation or exhaust. Consequently,
the specification of the highest efficiency fans and motors for use in the HVAC is an
important step toward the development of efficient systems. The EPA specifications
call for 90-95 percent efficient motors, a 10-15 percent savings over the customary
80-85 percent efficient motors. The specifications also call for high efficiency
centrifugal and axial fans with variable frequency drives. By combining the highest
efficiency fan design with variable speed demand high efficiency motors, a 15-20
percent overall savings in fan energy can be realized.
Heat Reclamation for Hot Water Generation
In the EPA facility, the high temperature hot water that has been circulated through
heat exchangers to generate steam for the main building maintains sufficient heat to
make domestic hot water. Consequently, circulating the water through an additional
heat exchanger to make domestic hot water is an efficient use of the "surplus" heat.
By maximizing the overall change in temperature, heat losses are reduced in site
utility piping. This means that more of the energy per gallon of water is used and
not wasted as system losses from site distribution.
Laboratory Fume Hoods
Laboratory fume hoods are vented enclosures provided for the safe handling of
hazardous substances. They prevent the escape of contaminants to laboratory air,
thereby providing containment. In addition, they typically provide most or all of the
exhaust for the entire laboratory.
During the design of the laboratories, it was determined that there were limited options
for conserving energy conservation in the fume hood systems while still meeting
current EPA safety performance standards. The air change requirement in the standard
chemical lab is 12 air changes per hour (ACH); other specialty labs can require up to
15 ACH. The design parameters at the outset of design were for a 1,400 cubic feet per
minute (CFM) conventional fume hood, with no provision for nighttime setback. This
EPA standard was based on the need for a minimum face velocity of 100 feet per
minute (fpm) with the sash fully open.
The EPAs new standard hoods were modified to provide for an 80 percent sash stop on
all of the hoods. The sash height reduction to 80 percent provides energy savings of 20
percent without compromising safety. This requires the researcher to manually override
the sash stop for setups within the hood, placing the hood in "alarm" mode, and then
to lower the sash back to the 80 percent stop or lower while chemicals are handled
within the hood. The sash height reduction requires that operators understand the
system and not attempt to work with the hood 100 percent open.
The design of the laboratories evolved to accommodate two-position variable air
volume control for each lab module. Called a "nighttime setback," this feature allows
for energy savings in the lab module during unoccupied hours. A two-position supply
volume box is provided in each lab module. Each fume hood is connected to a riser
with a two-position exhaust volume box in the penthouse. The system has been devised
so that when the fume hood is at maximum flow, the volume boxes are positioned to
provide for a flow of 1120 CFM through the fume hood. If the lights are off and the
sash is closed on the fume hood, the volume boxes will reduce the airflow through the
lab module by approximately 50 percent. This saves energy by reducing the air
handling unit flow rate and slowing down the motor on the fans. The reduced airflow
eases cooling and reheat requirements. Fan energy is also saved when the exhaust
requirements are reduced by using variable frequency drives on the exhaust fans.
Economizer Cycle
(aka "outside air economizer") A
system whereby cool outdoor air
is used, as available, to ease the
burden on a refrigeration cycle as
it cools recirculated indoor air.
Cooling (or heating)
coils as needed
25 deg.
No
recirculated
Economizer cycle controls
the relationships between
supply and return air:
When outside air is hot (or
very cold) the economizer
cycle is inactive
As very cold outside air gets
warmer, it can be blended with
recirculated air, and neither
heating nor cooling coils are
needed
When outside air is cool, it can
completely replace recirculated
air, making mechanical cooling
inactive
Source: Stein and Reynolds,
Mechanical and Electrical
Equipment for Buildings, 1992
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
58
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Conventional Fume Hood
One of the oldest forms of
laboratory fume hood, it is
designed so that all exhaust air is
drawn in through the front face
opening.This type of hood can
suffer from excessive face velocities
and poor containment because the
air velocity at the face increases
proportionately as the sash is
lowered.
Fume Hood Energy
Conservation Strategies
Sash Height Reduction
Because fume hood exhaust air
quantities are determined by the
area of the face opening and the
need to maintain a minimum face
velocity, a reduction in the sash
height reduces the total required
air flow.
Night Set Back
A sliding sash closes the fume
hood and slows air flow during
evening or unoccupied hours.
Variable Air Volume Fume Hood
Provides a constant velocity across
the hood face opening by varying
the supply and exhaust air volume
when the sash is opened or closed.
Requires sophisticated controls
and a response time of not more
than five seconds to safeguard
against backdrafts.
Horizontally Sliding Sash
Horizontal panels reduce the face
opening decreasing the total
required air flow.
Combination Sash Fume Hood
Horizontal sashes are used in
combination with vertical sashes,
providing the opportunity to save
air flow by restricting the sash
opening either vertically or
horizontally.
Other energy conserving options, such as full VAV and combination
vertical/horizontal sash fume hoods, were considered and rejected by the EPA team.
EPA placed a high priority on low maintenance solutions that do not require
expensive operator training. Some of the newer energy conserving strategies had too
few successful installations to validate them when the design decisions were being
made for the EPA Campus.
Industry Standard 6-Foot Hood
EPA Hood: Operational Mode
Sash
100%
open
1.400CFM
All the time
Sash
80%
open
1.120CFM
20% minimum savings all the time
EPA Hood: Set-Up Mode
EPA Hood: Night Setback (Unoccupied) Mode
»
Sash
1 00%
open
ALARM
1.120CFM
20% minimum savings a!! the time
Lights
off
)
Sash
closed
660 CFM
53% total savings
Heat Recovery for Laboratory Exhaust
Heat exchangers operate in a number of different ways depending on the medium that
is being used, and the proximity of the intake and exhaust streams. Their function is to
use waste heat and waste cooling to accomplish preheating and precooling. The
potential for energy savings can be quite high, particularly for building types like
laboratories that require large volumes of conditioned air to be exhausted.
A value engineering study prepared during concept design for the EPA facility
evaluated the cost-effectiveness of installing a glycol runaround system in the
laboratory air handling equipment. The glycol system was proposed because it
avoids possible contamination between air streams, and won't freeze in the outside
air stream. In the winter, warm exhaust air transfers heat to a glycol solution, which
is then pumped to the coil in the air handling unit to preheat outdoor air. Incoming
air is warmed as it passes over the glycol loop before passing through the heating
coil, thus reducing the energy required to heat the outdoor air. This is also true in
the cooling season where cooler exhaust air cools the glycol solution, which then
precools the outdoor air.
Much to everyone's surprise, the study indicated that the glycol heat recovery system
would cost $915,000 to install and approximately $8,900 more per year to run than
the system without the runaround cycle. This cost differential was attributed to the
extremely low electric rates of the local electric power provider and the absence of
profound, long-duration extremes in North Carolina weather. The glycol system had
increased fan static pressure caused by the heat recovery coils, and additional energy
59
Design Process: building Mechanical Systems
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requirements for the glycol loop pumps. The energy to run the reheat system was
enough of an additional load to actually make heat recovery a more expensive
system to operate. As a result, EPA did not install a heat recovery system, but
provided space in the mechanical penthouse to allow installation of a system should
technology and economics make heat recovery a prudent choice in the future.
CFC Free Refrigeration Equipment
Because of the impact CFCs have on the ozone layer, CFC refrigerants have been
largely replaced by HCFC substitutes. Federal legislation has mandated strict
phaseout dates that further impact decision making. Among the common
substitutes for CFCs are HCFC-22, which has one-twentieth the ozone depleting
potential of CFC-11 and will be phased out in 2020; HCFC-123 which has less
than half the ozone depleting potential of HCFC-22 and will not be phased out
until 2030; and HFC 134a, which has no measured ozone depleting potential and
does not have a phase out date scheduled at this time. There are pros and cons to
HCFC-123 and HFC-134a, the two most viable substitute refrigerants. While
HCFC-123 is more efficient, it is scheduled to be phased out of production due to
its ozone depletion potential. HFC 134a is a safer alternative that has less ozone
depleting potential, but is a higher pressure refrigerant that is slightly less efficient
and requires slightly larger equipment and more floor area.
In the end, EPA selected HFC-134a because it is a 0-rated refrigerant for ozone
depleting potential. Gas absorption chillers were rejected as an option because the
cost was prohibitive given the extremely low electricity rates at RTF.
Building Humidification
Humidification is recommended in regions where winter conditions are particularly
dry and may adversely impact the health and well-being of occupants in office
environments. In laboratories, humidification can be essential to the success of
research projects. To provide the necessary humidification, the EPA facility uses a
water atomizing system that employs compressed air and softened water to provide a
minimum relative humidity (RH) of 35 percent in the laboratories and offices. A
value engineering study verified that energy savings made this type of system cost
effective even with its higher first cost. Steam systems require high temperature hot
water to be converted to steam with special re-boiler generators that have inherent
inefficiencies, as well as heat loss from piping. With the water atomizing system,
cooling requirements are reduced because cool vapor from the humidifier acts as an
evaporative cooling medium, giving the system a certain amount of free cooling in
the air stream. Because of these savings, the cost of the system was acceptable.
Central Direct Digital Control (DDC) System
Central control systems allow building operators to have close control of their
equipment and save energy by allowing systems to be turned down or off when they
are not needed. The typical direct digital control (DDC) system uses a central
computer and remote control panels into which the various pieces of equipment are
wired for control. The system has an electronic base and is far more accurate than
the pneumatic (compressed air control) systems of the past. Even if the main
computer console goes down, the remote panels can stand alone and continue to
control the equipment.
A central DDC system has been specified to control all of the HVAC systems and
many of the electrical components as well. The building operator will be able to
monitor multiple control parameters including temperatures, pressures, whether
lights and fans are on or off, whether filters are clogged and other aspects of air
handling units as well as pumps and cooling tower operation.
Global Warming Potential
The ratio of the warming caused
by a substance to the warming
caused by a similar mass of
carbon dioxide.
Ozone-Depletion Potential
The ratio of the impact on ozone
of a chemical compared to the
impact of a similar mass of
CFC-11.
Ozone-Depleting Substances
Those chemicals that contribute
to stratospheric ozone depletion,
including chlorofluorocarbons
(CFCs), hydrochlorofluorocarbons
(HCFCs), halons, methyl bromide,
carbon tetrachloride and methyl
chloroform.
Central DDC System
Schedules start/stop
Optimum start/stop
Duty cycling
Load shedding
Demand limiting
Enthalpy economizer
Temperature set back
Supply air settings
Water temperature settings
Chiller optimization
Chiller demand limiting
Lighting systems control
Security systems control
Critical and maintenance alarms
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
60
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Systems to be
Commissioned
Each HVAC supply air system
Each HVAC exhaust air
system
HVAC hot water system
HVAC chilled water system
HVAC HTHW system
HVAC steam system
Fuel oil system
Animal watering system
Water heaters
Fire pumps
Raceway system
Conductor system and
wiring devices
Grounding system
Lighting control system
Fire and voice alarm system
Security system
Emergency stand-by power
system
These systems can be started, stopped and otherwise controlled for maximum
efficiency. Alarms will feed back to a central console so that the condition of all
equipment can be assessed at all times. As the actual building operating characteristics
are established, the system operators will be able to make adjustments to operating set
points to optimize system performance and reduce energy usage. A telephone interface
module (TIM) allows for modem interface and touch tone overrides from any touch
tone telephone. Wall thermostats provide office and lab occupants with digital readings
of temperatures within the office suites. Occupants can request adjustments with a
phone call to the building automation system operator.
Building Commissioning
In the past, commissioning has been used primarily as a procedure to verify the
performance of HVAC equipment. It ensures that equipment is installed and
operating properly before the building is occupied. Studies have shown that
buildings that are not properly commissioned can lose as much as 20 percent of
their operational energy efficiency due to improperly operating systems.
"Full systems" commissioning is becoming increasingly common. At the EPA
facility, operators and maintenance personnel have been included in the
commissioning process to enhance their understanding of the building's systems and
their intended performance. Participants have included EPA personnel such as the
building engineers, HVAC operation and maintenance personnel and building
security personnel. A separate testing and start-up procedure was required for the
DDC system to ensure that it is working properly and building engineers know how
to operate it.
Building Acceptance Test Manual
A Building Acceptance Test Manual was developed by the project team to provide
an operations manual for the building owner to use during commissioning and
occupancy. All building systems-HVAC, electrical, fire safety, security,
communications and architectural-were itemized and appropriate testing protocols
were identified. This document serves as an important guide for ongoing
maintenance and recommissioning over time.
61
Design Process: building Mechanical Systems
-------
Summary of major heating, ventilation and air conditioning systems.
Impact on Energy Efficiency
Variable Speed Drives
VAV Boxes in Office Areas
Air Economizer Cycle
Lab Air Handling Units -
Optimum Operating
Efficiency
Pipe Sizing
Two Position VAV for
Laboratories
Building Infiltration
Controls
HVAC Control System
Air Filter Pressure
Ductwork and Pipe
Insulation
High Temperature Hot
Water/Domestic Water
Generation
Water Atomizing
Humidification
Variable speed drives have been provided for all water pumps
and air handling units. Sensors in the piping or duct system
record fluctuations in static pressure or water pressure and
transmit a signal back to the variable speed drives, which then
slow down or increase the motor speed.
A standard Variable AirVolume (VAV) System is provided for
the office spaces. A variable speed drive on the air handler will
slow down the fan, thereby maintaining minimum system
pressure and saving fan energy.
Each air handling unit for the office space is equipped with a free
cooling economizer cycle.The air handling unit will operate at
100% outdoor air mode when the outdoor air temperature is
below the space return air temperature.When the temperature
drops, the system would then mix outdoor air and return air
in order to maintain temperature.
Each of the main lab buildings contains five air handling units.
As the building load increases, the control sequences will have
the units operate at 60%, 80% and then 100% to optimize
efficiency.
Piping has been sized so that the pressure drop is below the
recommended values in Standard 90.1 Section 9.5.5.1, creating
greater energy savings than required byASHRAE or the
applicable building codes.
Two-position air flow control for the laboratories: when the fume
hood is at maximum flow, the box is fully open to provide 1120 CFM
exhaust. If the lab is unoccupied and the hood sash is closed,
the boxes will go to a 50% position, saving energy by reducing the
air handling unit flow rate.
By ensuring that pressurization exists, outside air infiltration is
minimized to reduce loading on the heating system.
A direct digital control (DDC) central building automation
system will monitor and control all equipment set points to
maximize efficiency and monitor performance.
Static pressure sensors for each filter bank in all air handling
units monitor pressure drop across filters and alert maintenance
staff as when they need to be changed, thereby improving
energy efficiency of fans.
Meets the ASHRAE Energy Conservation Standard 90.1
requirements.
High temperature hot water is circulated through heat
exchangers to generate steam and also to make domestic hot
water.This means that more of the energy per gallon of water
is utilized and not wasted as system losses in the
site distribution.
A water atomizing system for humidification has been
incorporated into the laboratories and office spaces. Also serves
as an evaporative cooling medium.
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
62
-------
United States Projected
Water Savings from
Efficiency Standards
Water Fixture Use
(Billions m3/year)
25.
20.
15.
10.
1995 2000 2010 2015 2020
Without EPACT standards
With EPACT standards
Source: WorldWatch Institute, 1996
Key Issues to Consider
Meet or exceed the EPACT
fixture requirements for
water conservation
Consider automatic shut-off
faucets in high-use areas
Consider alternative toilets
and urinals
Eliminate the use of chillers
that use "one pass" water
Explore water-efficient
cooling tower options, such as
drift eliminators and
automated blow down
Water Conservation
Building operations consume an estimated 16 percent of the fresh water in the
United States.8 The portion used for landscape irrigation can be controlled through
the use of native plantings and water reuse strategies. The water usage for
equipment will vary based on the types of systems used, with one-pass cooling and
evaporative strategies using the largest quantities of water. While water usage for
plumbing fixtures has been reduced considerably due to the mandatory water
efficiency requirements in the Energy Policy Act of 1992 (EPACT), more can be
done to promote water conservation.
Water Conserving Fixtures
The EPA Campus uses EPACT standard low flush toilets and urinals. Lavatories
used for hand washing have been demonstrated to perform quite well at 0.5 gallons
per minute, instead of the 2.5 allowed by the EPACT. Consequently, aerators and
flow restricting nozzles for faucets and showers were used to make the facility more
1992 Energy Policy Act (EPACT) Requirements
for Water Conserving Fixtures, effective 1/1/94
Shower Heads and Faucets
Fixture Type
Showerheads, any type (excluding safety showers)
Lavatory faucets
Lavatory replacement aerators
Kitchen faucets
Kitchen replacement aerators
Metering faucets
Water Closets and Urinals
Fixture Type
Gravity tank-type toilets (non commercial)
Gravity tank-type toilets (commercial)
Flushometer tank toilets
Electromechanical hydraulic toilets
Blowout toilets
Urinals (any type)
Maximum
Water Use
2.5 gallons per minute
2.5 gallons per minute
2.5 gallons per minute
2.5 gallons per minute
2.5 gallons per minute
.25 gallon per cycle
Maximum
Water Use
1.6 gallons per flush
1.6 gallons per flush
1.6 gallons per flush
1.6 gallons per flush
3.5 gallons per flush
1.0 gallons per flush
63
Design Process: Water Conservation
-------
water efficient than the EPACT standard. For the EPA Campus, manual flush
valves were used, and touchless "sensor-operated" lavatories provide for improved
sanitation and heightened water conservation. Availability of hot and cold water has
been improved by a recirculating system with automatic temperature controls.
Water Efficient Cooling Towers
Cooling towers provide an efficient complement to chilled water cooling systems,
by rejecting the waste heat from the recirculating chilled water system. These towers
maximize the surface area contact between outdoor air and the warm waste water,
creating cooling action through evaporation. They have been made more water
efficient by limiting "drift," or excessive water content, in the hot air that is rejected,
and by recirculating the condensate water. Most, but not all, cooling tower
manufacturers have incorporated drift eliminators as standard features that
decrease water consumption.
Cooling towers, however, must be protected from corrosion and contamination.
Typically, this is done with chemical additives. The type and the quantity of additive
used to treat the water varies regionally due to natural variations in the water
chemistry. Generally, these additives include corrosion inhibitors, dispersants, algae
and bacteria control agents, alkaline additives and oxygen scavengers. To determine
the correct amount of a given additive for a specific cooling tower, periodic water
tests are performed. The tests enable the development and regulation of a
maintenance program with an automated system that controls dosage and
"blowdown." Blowdown is the term for water that is discharged from the
condensate water system to control the concentration of chemicals, salts and
other impurities in the circulating water.
The EPA Campus has incorporated some innovative features to improve the water
efficiency of cooling towers, generating an estimated savings of approximately four
million gallons a year. These features include a dynamic water analysis system that allows
the quantity of blowdown to be reduced to a minimum. The system regularly monitors
water quality, allowing better control of the additive dosage and thereby reducing the
need to apply a "safety factor" in anticipation of days when the water quality may be
atypical. The dynamic sampling system increases the cycles of concentration from 6-8,
which is the industry standard, to 12-14. While the system conserves water, it also
reduces reliance on chemicals and has a two- to three-year payback.
Ozone Treatment for Cooling Towers
An ozone system was considered early on by the project team as a nearly chemical-free
option for treating condensate water in the cooling towers. The ozone system offered
an attractive option because it not only conserved water, but it also greatly reduced
reliance on chemicals for water treatment. Unfortunately, the system could not be cost
justified for this application. The first cost premium for the system was estimated at
$300,000-350,000, and the system also had higher maintenance costs.
Alternative Technologies
Alternative technologies were defined by the EPA project team as those that are not
yet common in the marketplace. Some technologies were included in this category
because they are new. Others were included even though they had not yet gained
widespread acceptance because they only proved cost effective where rates for
electricity, water or sewage treatment have become especially high. This was a
subjective judgment that is not based on the merit of the individual technologies.
Though all of the alternative technologies considered for the EPA Campus had
positive environmental characteristics, most would have come at a significant cost
Cooling tower
Cooling Towers Save Water
The EPA campus uses innovative
features that will save about 4
million gallons of water per year.
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
64
-------
Key Issues to Consider
Optimize energy and water-
efficiency of standard facility
design and systems
Determine total resulting
energy and water-use needs,
including daily and seasonal
variations
Gather data on local and
micro-climate, including solar
incidence, average monthly
temperature, wind patterns,
relative humidity and average
monthly rainfall
Research currently available
technologies for hydrogen fuel
cells, wind power, photo
voltaics, solar water heating,
point of use water heating,
grey water recycling,
rainwater catchment and
pervious paving
Determine cost effectiveness
of each alternative technology
explored
Investigate local, state and
federal financial incentive pro
grams for alternative
technologies
Photovoltaics (PV)
Solid state semiconductor devices
that convert light directly into
electricity.They are usually made of
layers of silicon or other
semiconductor material with traces
of other elements. PV cells are
housed and wired together in
"modules," which may be used
singly or grouped in an "array." PV
systems may include battery storage
or may be wired directly to the
utility line, although some systems
may use neither. Systems with
batteries need electronic devices to
control their charging or limit their
discharging of the batteries.
premium. In the interest of balancing environmental benefits with cost and
functional performance, EPA chose to use only those alternative technologies
which were most appropriate for this project.
It should be noted that the determination of cost effectiveness for some technologies
was greatly impacted by the costs of electricity in RTF. Electricity costs vary widely
across the U.S. At the current commercial rate in RTF of 4-5 cents per a kilowatt-
hour (KWH), the cost of electricity is low. For example, rates in New York City or
Boston are closer to 12-13 cents per KWH. While the low rate keeps the cost of
operations down, it proved to be a disincentive to incorporating energy-efficient
technologies that have marginal cost benefits.
Photovoltaics
Photovoltaics, or solar electric cells, convert sunlight into electricity. Many different
types of technologies are available, but the two basic types are polycrystalline and
thin film. The polycrystalline options are generally more efficient and more
expensive than thin film options.
Photovoltaics were evaluated for the EPA Campus. However, working with a limited
construction budget, the project could not bear the full first cost of photovoltaic
electric systems for the entire campus. By exploring alternative funding strategies,
the project team was able to incorporate two photovoltaic applications onto the
campus.
Aided by grant funds from the federal Department of Energy and the State of
Virginia, EPA chose to install a 100 kilowatt array on the roof of the National
Computer Center building. This solar array provides power directly to the building.
Since the building houses extensive computing systems, and has an unusually high
power demand, the building is also connected to the electrical grid.
EPA also negotiated a lease-purchase arrangement with the local power company
to install 70 photovoltaic lights along the site roadways-creating one of the largest
solar road lighting projects in the U.S. Since the lights would be owned by the
power company, prior to an optional buyout by EPA, the power company took
advantage of a 35% tax credit from the State of North Carolina for solar power
equipment purchases. The tax credit significantly reduced the cost of the solar lights
to make the system cost-justifiable for EPA. Over a 20-year life cycle, EPA expects
these solar lights to cost the same as standard street lights.
Fuel Cells
Fuel cells are highly efficient engines that convert natural gas into heat energy and
electricity. For building applications, they are most appropriately used where there is
a constant demand for electricity and heat 24 hours a day. Because of the size and
weight of fuel cells, they need to be integrated into early conceptual planning to be
accommodated successfully. In 1992-93, when the EPA Campus was in the early
stages of design, fuel cells were not a viable option and were ruled out. They were
later considered for the National Computer Center as a source for conditioned
power and a replacement for the uninterruptible power supply, but again proved
cost prohibitive. However, fuel cells have evolved rapidly over the past decade, and
should be considered as a possible cost-effective source for large constant loads.
Wind Power
Wind generators are becoming increasingly prevalent in some parts of the country.
They were determined to be inappropriate for the EPA Campus because of the
forested nature of the site, the relatively low wind velocities in the area, and the
65
Design Process: Alternative Technologies
-------
abundant low-cost electricity available on the site. Trees would have to be cleared to
make room for wind generators on the site and this would have defeated the effort
to minimize habitat disruption.
Solar Hot Water
Solar hot water technology provides an efficient application of the sun's energy to
directly heat water for use. Given the low local cost of electricity, solar hot water heating
offered the most likely cost-effective solar alternative. However, the central water system
proposed for use on the EPA Campus was also very efficient and made use of heat
recovery. Consequently, solar hot water generation was never formally evaluated.
Central Hot Water vs. Point-of-Use Hot Water
Point-of-use heaters for water can be an attractive option because heat is only
generated when it is needed and heat energy is not lost in transmission as hot water
is pumped and recirculated through the building. A study completed for the EPA
facility to evaluate the potential benefit of using a point-of-use system for water
heating made a clear case for the use of the central system. While the first cost of
the point-of-use system is slightly lower, the life cycle costs are dramatically higher,
since these systems are less efficient than a central hot water system. Heat recovery is
more easily accommodated into a central system and maintenance is simpler when
fewer pieces of equipment require servicing.
Point-of-Use versus Central Hot Water Heating
Central Hot
Water Plan
Point of Use
10Year Warranty
Point of Use
20 Year Warranty
$140,694.90
$65,400.00
$1,600.00
$13,172.78
$6,700.00
$799,468.13
$20,744.00
$109,156.00
$20,250.00
$46,147.76
$19,996.52
$2,151,799.00
$20,744.00
$148,900.00
$20,250.00
$34,802.94
$16,330.00
$1,744,534,74
Hot water piping system
Water heaters
Miscellaneous installation
Annual energy cost
Annual maintenance cost
Total 20-year cost
Grey Water Reuse
Grey water is defined as all wastewater not originating from toilets or urinals. It includes
water from lavatories, coffee sinks, showers and drinking fountains. The grey water study
for the EPA Campus considered reuse of various sources of grey water ranging from the
highly purified reverse osmosis (RO) water used in laboratories through the condensate
from air handlers, and eventually to all the possible grey water sources combined. North
Carolina codes restrict grey water use within the building, and the EPAs outdoor
irrigation requirements were minimal. An option that treated black water (water from
flushing fixtures) was also considered.
One interesting discovery from this study, however, was that there were nearly
enough relatively clean water sources to provide the entire water requirement for
flushing and irrigation without any need to introduce expensive filtration systems
for water reuse of wastewater streams that would contains soaps and other
contaminants. The water generated from condensate alone is 500-3,100 gallons per
hour during the cooling season.
Inverter
Load
Battery
Typical PV system including
battery and controller, Solarex
Fuel Cell
A fuel cell converts chemical
energy directly into electricity via a
modified oxidation process; that is,
by reversing electrolysis. By
combining hydrogen and oxygen
from an outside source, the fuel cell
makes electricity like a battery that
does not need to be recharged
because the fuel comes from
outside. The process also produces
heat, water and carbon dioxide
depending upon the fuel used.
Solar Water Heater
A system in which direct heat
from the sun is absorbed by
collectors and transferred by
pumps to a storage unit. Typically,
the heated fluid in the storage unit
conveys its heat to the building's
hot water via a heat exchanger.
Controls are needed to regulate
the operation.
Point-of-Use Water Heater
A small water heater that services
only the water to be used at one
location, such as a single lavatory
faucet, rather than storing hot
water in a central tank and
distributing it throughout the
building via pipes, from which
much of the heat will escape.
Some point-of-use water heaters
are "tankless," while others use
very small storage tanks at each
location.
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
66
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Grey Water Recycling
Any system of reusing wastewater
not originating from toilets or
urinals. In commercial buildings
this includes waste water from
lavatories, showers, drinking
fountains and janitor's sinks.
Sometimes it includes stormwater.
Grey water may be reused once
to flush a toilet before being sent
to sewage treatment or may be
diverted to an irrigation system,
depending upon its contaminants.
Grey Water Reuse Study
First Cost Premium
Annual Costs '
Annual Water Savings
Payback
Option 1
Reuse RO
reject only
$70,940
$6,500/yr
$6,380/yr
N/A
Option 2 Option 3 Option 4 Option 5
Reuse all Option 2
pure water plus clear
waste condensate
streams from air
handlers
$147,700 $409,500
Option 2
plus grey
water
Option 4
plus black
water
reuse
$744,400 $1,480,000
$7,400/yr $11,600/yr $26,800/yr $68,800/yr
$15,000/yr $23,000/yr $27,200/yr $29,100/yr
19.4 years 35.9 years 1860 years N/A
1 Annual costs refers to annual energy and maintenance costs
Rainwater Catchment
A system that gathers rain that
falls on a roof or yard and
channels it to a storage tank
(cistern).The first wash of water
on a roof is usually discarded and
the subsequent rainfall is captured
for use if the system is being used
for potable water. Alternatively, a
sand filter may be used.
With minimal need for irrigation and restrictive codes for indoor use, along with
a very high cost for dual plumbing systems, EPA opted not to include grey water
reuse in the project.
Rain Water Catchment
Rain water catchment refers to systems that collect rain water in storage tanks or
cisterns for reuse in the building or for irrigation. This was viewed as a landscape
irrigation feature, and because nearly all irrigation requirements had been eliminated
from the design, this option did not receive a formal investigation. Rain cisterns
were considered as a possibility but were quickly eliminated due to code constraints
for indoor use and little need for outdoor watering.
Key Issues to Consider
Gather data to evaluate life-
cycle impact of materials and
systems
Balance environmental
performance with cost and
durability
Dimension materials carefully
to minimize waste
Avoid the unnecessary use of
finish materials
Design for disassembly and
reuse of materials
Establish maximum volatile
organic compound (VOC)
content levels
Establish minimum recycled
content levels
Building Materials
Through their design decisions and specifications, architects and engineers directly
influence the purchase of millions of tons of materials each year. These design
decisions impact the marketplace and influence the kinds of products that industry
produces. In turn, these market decisions affect the selection of raw materials, the
use of energy and water, the depletion of non-renewable resources and the creation
of waste and pollution.
The project team for the EPA Campus considered the environmental impact of
building materials over their entire life cycle in selecting materials for the new
facility. Then, as the specifications were developed, specific performance criteria
were documented to the greatest extent possible.
Life-Cycle Impacts of Materials and Products
Most standard building materials and products have a fairly wide field of manufacturers
and, consequently, products vary. Therefore, selecting environmentally preferable
building materials and products requires a proactive approach that examines the
environmental and health impact of a product at each stage of its life cycle.
Raw Material
Composition
Production
Process
Packaging
& Shipping
Installation
&Use
Resource
Recovery
67
Design Process: Building Materials
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Raw Material Composition
Are the materials nontoxic? Renewable? Salvaged? From a sustainable source?
Do they contain recycled content?
Production Process
How much energy and water is used in the manufacturing process? How much
solid, aqueous and gaseous waste is emitted? Is manufacturing waste reused? Is
the manufacturing plant energy efficient? Does the manufacturing plant
conserve or reuse water?
Packing and Shipping
Is the product locally manufactured? Is minimal, reusable or recycled packaging
used? Are efficient shipping methods used?
Installation and Use
How durable is the product? Can it be repaired? Is the installation method
hazardous? Does the product, or related adhesives or finishes, produce chemical
emissions? Is the product low maintenance? Do maintenance procedures produce
chemical emissions?
Resource Recovery
Is the product salvageable, recyclable or biodegradable? Does the manufacturer
have a take-back program?
Durable Materials
EPAs long-term commitment to its new facility and its location in RTF is reflected
in the stated design goal to create a "100-year-building." This view is intended to
reduce long-term operating and maintenance costs. Highly durable materials have
an environmental advantage because fewer materials are used over time and less
material is disposed of. Examples of durable materials selected for the facility
include cementitious terrazzo, mud-set ceramic tiles and the precast concrete
exterior wall system. The ceramic tile will last almost forever when properly
installed, and the cladding is anchored to masonry backup walls, detailed with
stainless steel flashing, and sealed to enhance longevity and maintainability.
Recycled Content
Specification of materials with recycled content helps to conserve virgin resources
and drives the market for recycling. Therefore, the specification for the EPA facility
included detailed requirements for minimum recycled content by material type. The
EPAs Recovered Materials Advisory Notices (RMAN) provided preliminary
guidance. Then, research into market availability was performed using a detailed
questionnaire. The goal was to evaluate the cross-section of products available so a
competitive range of manufacturers could be selected.
Products specified with recycled content include rubber flooring, ceramic tiles,
asphalt paving, cast-in-place concrete, insulation, wood fiberboard, gypsum
wallboard and more. The following figure presents all of the recycled content
provisions in the final specification. The list represents minimums and many
materials have been procured that contain more than the minimum required. The
following chart summarizes the improvement that the specification represents
compared to standard practice for many of the material types.
During construction, EPA was unable to find local asphalt plants that could
produce 25% recycled content asphalt as designed. The quality of the specified
asphalt from plants unfamiliar with this production became a concern. As an
alternative, EPA accepted asphalt with slightly lower recycled content which
incorporated roofing shingle scrap-a waste that is typically difficult to recycle.
Palette of finish materials used in
the main facility
Sample of EPA
Campus Materials
4 acres of concrete block walls
2 acres of Low-E glass
35 acres of drywall
7 acres of carpet
12 acres of ceiling tile
2,861 interior doors
19 miles of telcom conduit
What is RMAN?
RMAN stands for Recovered
Materials Advisory Notice. It
provides guidance on recycled
content materials and was issued
by the EPA in May 1995.
Construction materials include:
Cement and concrete
containing fly ash (previously
issued January 28,1993 as 48
FR 4230)
Building Insulation (previously
issued February 17,1989 as
54 FR 7327)
Structural fiberboard
Laminate paperboard
Plastic pipe and fittings
Geotextiles
Cement/concrete using
ground granulated blast
furnace slag
Carpet
Floor tiles
Patio blocks
Hydromulch
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
68
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RMAN Update
An update was issued in
November 1997, that added the
following construction materials
categories:
Latex paint
Shower and toilet partitions
Parking stops
How is RMAN Enforced?
Once the EPA designates items
that are or can be made with
recycled content, RCRA section
6002 requires any procuring
agency when using appropriated
federal funds to use the highest
percentage of recovered material
practical.
Pre-Consumer Waste
(aka in-plant-scrap)
Comes from material off-cutting,
damaged material or other
manufacturing waste.
Post-Consumer Waste
Comes from products discarded
by end users (consumers).
Examples include newspapers,
magazines, beverage containers,
building materials, etc.
Renewable Materials
Are replenished at a rate equal to
or greater than their rate of
depletion.
Heavy Metals
Includes mercury, lead, cadmium,
thallium, cobalt, nickel and
aluminum. Most are very toxic and
persistent in the environment.
Recycled ioo
Content
Fiberglass Mineral wool Acoustic Rubber Structural Material
batt/board insulation/ panel floor fiberboard
insulation fire safing ceilings tiles
| Specified | Conventional
Comparison of Recycled Content Levels Specified with Conventional Materials
Minimum Required Recycled Content
Material or Product
Asphaltic concrete paving
Reinforcing steel in concrete
Reinforcing bars in precast concrete
Concrete masonry unit
Recommended Recycled Content
25% by weight '
60% recycled scrap steel'
60% recycled steel2
50% recycled content
Reinforcing bars in concrete unit masonry 60% recycled steel'
Framing steel
Fiberglass batt insulation
Fiberglass board insulation
Mineral wool insulation
Mineral wool fire safing insulation
Gypsum board
Facing paper of gypsum board
30% recycled steel2
20% recycled glass cullet3
20% recycled glass cullet3
75% recycled material (slag) 3
75% recycled material by weight (slag) 3
10% recycled or synthetic gypsum
100% recycled newsprint including post consumer waste ;
Mineral fiber sound attenuation blankets 75% recovered material by weight (slag) ;
Steel studs, runners, channels
Acoustic panel ceilings
Ceiling suspension systems
Rubber floor tiles
Hydromulch
Structural fiberboard
60% recycled steel2
60% recycled material by weight
60% recycled material
90-100% recycled materials 3
100% recovered materials 3
80-100% recycled content3
1 As per North Carolina Department of Transportation (NCDOT) recommendation.
2 60% represents the average recycled content for the U.S. steel industry. Use of U.S. manufactured
steel will meet this requirement.
3 As per EPA Comprehensive Guideline for Procurement of Products Containing Recovered
Materials (60 FR 21370, effective 5/1/95) and its corresponding Recovered Materials Advisory
Notice (RMAN), 5/1/95.
69
Design Process: Building Materials
-------
Local Materials
Many materials selected for the EPA Campus were locally manufactured including
concrete, brick pavers, concrete masonry block and precast wall panels. The
specification of local materials was a good environmental choice because, all other
things being equal, it minimized energy use and the pollutants generated during
transportation. Local materials also are generally less costly and have shorter lead
times than alternatives that need to be shipped long distances.
Consideration of local markets also affected the development of the specifications in
a more general way. As environmental specification requirements such as minimum
recycled content were being developed, the project team researched the potential for
local manufacturers to meet those requirements. The team did not want products,
especially bulky materials such as drywall, to be shipped from remote locations just to
satisfy an extreme environmental requirement. Consequently, trade-offs were made
and the final design specifications reflected those products in the local market with
better-than-average environmental performance.
Low Toxic and LowVOC Materials
Volatile organic compounds (VOCs) are carbon-based chemicals which are in a
gaseous phase at ambient temperatures. VOCs can include irritants and some
carcinogens that are commonly found in building materials. VOCs are emitted from
these materials as a result of the selection of raw materials and intermediate
chemicals used in manufacturing processes.
EPA specifications require low-VOC adhesives, finishes, sealants, joint compounds
and paints. See the following figure for a complete listing of requirements.
Certifications were also required to document that no heavy metals were present
in paints, adhesives and sealants.
For the building occupant, the concern over VOCs involves the extent to which
they are "off-gassed" into the indoor air from a specific material. VOCs for liquid-
based products can be measured in grams per liter (g/L). Grams per liter represents
the total quantity of VOCs in the material; the volatility of the material determines
how quickly they will evaporate from the material surface.
Material selection to reduce VOCs in the building interior is an excellent way to
practice pollution prevention. Many commonly used products have been
reformulated to be water-based instead of solvent-based. Simply reducing the
quantity of solvents can lead to performance problems, as was the case when the
first generation of low-VOC paints and adhesives was developed. However, many of
the reformulated products today are equal to or superior to their conventional
solvent-based counterparts. For example, a good quality, high-performance acrylic
latex paint can outperform the conventional alkyd enamel that has typically been
used for high-wear applications in all categories of performance: hardness, abrasion
resistance and washability. With the myriad of options that exist for paints and
coatings (which are constantly changing), it is extremely important to research the
available options and reference performance standards when specifying.
VOCs
(Volatile Organic Compounds)
Chemicals that are carbon-based
and evaporate from material
surfaces into indoor air at normal
room temperatures (referred to
as off-gassing).
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
70
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Performance
Standards for Paint
The durability of paints and
coatings is a critical factor of their
total life-cycle impact: low-toxic
paints that require additional coats
to cover or that must be
re-coated more often than
conventional products have lesser
overall environmental advantages.
Applicable Testing Standards
for Interior Paint
Performance
ASTM D2486-89 for
scrubbability (abrasion
resistance)
ASTM D2805-88 for hiding
power (opacity)
ASTM D3359-90 Method B for
washability (stain resistance)
Low-VOC Content Requirements
Material or Product | VOC Content
(Grams/Liter)
Form Release Agents 350
Plastic Laminate Adhesive 20
Casework and Millwork Adhesives 20
Transparent Wood Finish Systems 350
Cast Resin Countertop Silicone Sealant 20
Garage Deck Sealer 600
Water Based Joint Sealants 50
Non-Water Based Joint Sealants 350
Portland Cement Plaster 20
Gypsum Drywall Joint Compound 20
Terrazzo Sealer 250
Acoustic Panel Ceiling Finish 50
Resilient Tile Flooring Adhesive 100
Vinyl Flooring Adhesives 100
Carpet Adhesive 50
Carpet Seam Sealer 50
Water Based Paint & Multicolor Finish Coatings 150
Solvent Based Paint 380
Performance Water Based Acrylic Coatings 250
Pigmented Acrylic Sealers 250
Catalyzed Epoxy Coatings 250
High Performance Silicone 250
Casement Sealant 50
Liquid Membrane-forming Curing & Sealing Compound 350
71
Design Process: Building Materials
-------
Sustainably Harvested Wood
Wood was used in very limited quantities as an accent material in the new facility.
In addition, all finished wood millwork and paneling was specified to come from a
certified sustainable source. All of the species specified are domestic hardwoods.
Wood that was used has been mounted with clips that allow for future removal and
reuse as needed. When wood paneling was reviewed in value engineering, the team
chose to maintain the aesthetic qualities of wood in the design, but opted to use
half as much as originally intended.
Resource Recovery
The impact of resource recovery was addressed throughout the material selection
and detailing process. The objective was to enhance the potential for future
recyclability, reuse or salvage. If these options proved impractical, then the potential
for enhanced biodegradability was considered. Use of metals without alloys,
mechanical fastening of wood panels and specification of certified recyclable
carpeting are examples of ways that recycling was encouraged. With a facility that
will use more than seven acres of carpet, the team believed it was very important to
be certain that the material could be returned for recycling at the end of its life.
Site Materials
When working on a 133-acre site with a building footprint of more than 10 acres,
the quantities of material generated during site clearing, excavation, roadwork and
landscaping can become significant. Consequently, every effort was made to consider
the site when thinking about environmentally preferable materials. Reuse of on-site
material proved to be an especially sound environmental initiative because it
conserved resources and eliminated waste at the same time. All land-clearing debris
was shredded for use as landscaping mulch or as a soil amendment. Excavated rock
was crushed for use as fill material. The project team also found opportunities to use
large quantities of recycled materials. For example, concrete aggregate and recycled
asphalt are used in the roadwork, and the hydromulch is a 100 percent recycled
cellulosic or wood product.
Government Procurement Requirements
Government procurement rules require that a minimum of three products be
capable of meeting the specification to ensure a competitive bid. While it is good
practice to ensure competitive bidding on all projects-not just for government
contracts-it can limit the use of some emerging new "green" products. Although
this proved to be a challenge for the EPA Campus project, designers were able to
identify competitive sources for all materials specified.
Indoor Air Quality
The quality of indoor air delivered to the breathing zone can influence the health,
comfort and workplace productivity of a building's occupants and visitors. To
ensure that indoor air quality (IAQ) concerns were integrated throughout the design
process, EPA made design for good IAQ a prominent issue in its request for
proposals and in its design contract with the A/E. All significant program
requirements, design criteria and design features were documented in an Indoor Air
Quality Facility Operations Manual developed by the A/E team, which will provide
guidance for the IAQ program in the occupied facility.
Source Control, Source Isolation and Source Dilution
Traditional methods of ensuring good indoor air quality rely almost exclusively on
ventilation strategies. In these instances, fresh air is introduced into the space to
Certifying Sustainably
Harvested Wood
The Forest Stewardship Council
accredits agencies to certify
forestry operations and chain-of-
custody wood products
distributors.Two major FSC-
accredited agencies include
Scientific Certification Systems
and the Rainforest Alliance's
Smartwood Program, which has
a growing number of regional
affiliates across the United States.
CERTIFIED
WnJkniil.JI-.ic
it! I OKI IT tfiMtlRVJIMM MOM AM
Key Issues to Consider
Designate building a non-
smoking facility
Test for radon
Require full-systems
commissioning
Adopt ASHRAE 55-1992
Adopt ASH RAE 62-1989
Locate intakes and
exhaust to avoid
re-entrainment
Limit use of fibrous material
exposed to the airstream,
including duct liner
Select "low-emission" materials
Develop IAQ management plan
for construction
Designate an IAQ manager.
Ventilate, but don't "bake out"
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
72
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WhatisaVOC?
Volatile Organic Compounds
(VOCs) are carbon-based
chemicals that contain carbon
molecules are volatile enough to
evaporate or "off-gas" from
materials surfaces into indoor air
at normal room temperatures.
VOCs include Methane, Ethane,
Methylene Chloride,
1,1,1-Trichloroethane, CFCs,
HCFCs, MFCs, Formaldehyde and
other chemical compounds.
Source Control
Eliminates potential contaminants
at the source, preventing their
entry into the building.
Source Isolation
Physically separates potential
sources of contamination from the
airstream.
Source Dilution and Removal
Utilizes ventilation and filtration to
dilute and remove contaminants in
the airstream.
dilute contaminants that accumulate over time. A more proactive and cost-effective
strategy involves a life cycle approach to indoor air quality. The EPA campus
approach employs source control, source isolation, and source dilution for design
and construction, together with an integrated IAQ management plan for the
operations and maintenance phase.
Source control strategies eliminate possible sources of contamination before they are
introduced into the building. Examples include designating a building as non-
smoking, limiting the use of exposed friable fibrous materials which can become
airborne, and avoiding possible sites of microbial growth. The judicious selection of
building materials can minimize emissions of VOCs, toxic chemicals and other
irritating substances.
Source isolation strategies control sources of contamination that cannot be
completely eliminated. Office buildings, for example, will contain copy machines,
food preparation areas, loading docks and toilet rooms. In addition to these sources,
the EPA Campus has chemical and biological laboratories that could pose significant
risk to the air supply in the case of an accidental spill or release. All of these areas are
separately ventilated to the outside so that exhaust air is not recirculated into the
buildings. Building pressurization and appropriate location of building openings
further reinforces source isolation. To ensure proper isolation of laboratory exhaust
stacks from air intake vents, EPA built a scale model and ran a wind tunnel study to
test worst-case atmospheric conditions. As a result of the study, the exhaust risers were
extended 10 feet higher into the air.
Source dilution, the final method in the hierarchy of IAQ control strategies, refers to
ventilation and filtration of building indoor air. Flexible design combined with
commissioning at the end of construction ensures ventilation effectiveness. Temporary
ventilation is used to purge the building of contaminants during construction. By
ensuring ventilation effectiveness, indoor air quality is enhanced and energy
efficiency is improved.
Designing for Indoor Air Quality
Factors that impact IAQ include outdoor air quality, site conditions, building and
HVAC design, interior design, materials selection and construction procedures. Design
for IAQ requires a strong dialogue between all members of the team. An IAQ advocate
should be identified to champion IAQ issues in project team work sessions. An IAQ
manager also should be identified on the owners team to track issues as design and
construction progress, and to help manage the IAQ program in the completed facility.
IAQ Facilities Operation Manual
The EPA project team created the Indoor Air Quality Facilities Operation Manual to
document design decisions that will impact IAQ throughout the life of the facility, so
future building renovations will not undermine those features. This manual also
describes lAQ-related construction provisions including IAQ testing of materials,
sequence of finish installation, temporary ventilation, baseline IAQ testing and
commissioning. Preprinted forms, including HVAC Equipment Inspection Forms and
an IAQ Management Checklist were developed to guide building operators throughout
the occupancy phase.
Indoor Air Quality vs. Energy Efficiency
The design team took great care to balance energy efficiency with good indoor air
quality. While an abundant supply of fresh air with frequent air circulation will help
promote good IAQ, it can be energy-intensive. The challenge for the EPA campus
project was to strike a balance-optimizing IAQ performance without creating an
excessive energy demand.
73
Design Process: Indoor Air Quality
-------
Fortunately, some strategies promote good IAQ while at the same time saving
energy. For example, outside air economizers provide EPA's offices with "free
cooling" when weather conditions are right. These economizers are digitally
controlled and filter the outdoor air to remove mold spores, pollen and other
contaminants while bringing in increased quantities of fresh air."
EPA's offices are conditioned with a simple, low-cost "straight" VAV system. This
was deemed to be a better choice than a fan-powered VAV system, which uses more
energy and demands more maintenance. Using indoor air modeling based on this
system, the design team calculated the air circulation rates that would be required to
meet ASHRAE recommendations for fresh air supply. In order to achieve
ASHRAE's recommended minimum of 20 CFM outdoor air per person, the system
could be set as low as only one air change per hour (ACFi). But since air movement
is just as important as fresh air in achieving good IAQ, the VAV system was set to a
minimum of 2.25 air changes per hour (ACH)-about twice the minimum indicated
by using the ASHRAE standard alone.
The office heating and air conditioning system has also been designed to constantly
supply a minimum of 25% outdoor air. Based on actual demand, however, this
percentage can be increased. Carbon dioxide monitors continually sample the air in
return plenums to detect CO2 buildup in offices and meeting spaces. If levels are
high, indicating increased human activity in the space and a higher demand for fresh
air, the ventilation system will respond by bringing in more outside air. By preventing
the excessive use of outdoor air and supplying more fresh air when needed, the CO2
monitoring approach will save energy while promoting healthy IAQ.
Low-Emission Materials
Chemicals present in building materials and products can lead to the off-gassing of
substances that are irritants and, in some cases, even health hazards in the interior
environment. Off-gassing is measured in emission rates or emission factors, which
can vary significantly for similar materials by different manufacturers. Without
testing, emission factors are difficult to ascertain. The EPA project team sought
published reports of previous studies and some material manufacturers were willing
to share testing data, however the information was still scarce.
In the absence of testing data, one of the few resources for evaluating chemical
content is the Material Safety Data Sheet (MSDS) on which the manufacturer is
required to list all chemical constituents making up at least one percent of the
material, and not deemed "proprietary." For liquid-based materials such as paint and
adhesives, the total concentration of VOCs is listed in grams per liter. However, the
MSDS is limited in that the manufacturers may omit chemicals that they consider
trade secrets, and the MSDS does not list compounds that result from reactions
among the constituent chemicals.
IAQ Testing of Materials
IAQ testing and modeling gave the team an indication of what air quality would
ultimately be like in the building. The purpose was to determine the composition
and the rate of chemical emissions. The testing is typically conducted in either a
large or a small-scale environmental chamber that has been carefully designed and
instrumented. Using a predictive modeling tool developed by EPA staff called
EXPOSURE, the emissions testing results were then used to predict the ultimate
concentration of indoor air contaminants that would result over time, based on the
anticipated ventilation rates.
Factors That
Impact Indoor Air Quality
Outdoor Air Quality
Building exhaust from adjacent
buildings
Vehicle exhaust from adjacent
roadways
Releases from adjacent
industrial and agricultural sites
Soil gas (radon)
Site Conditions
Vehicle exhaust
Pesticides and fertilizers
Sporulating plants
Building and HVAC Design
Location of fresh air intakes
and exhaust
Interior pollutant-generating
sources, e.g., print rooms,
loading docks
Air and moisture flows through
the exterior wall
Fibrous insulation exposed to
the airstream, e.g., internal
duct liner
Ventilation and filtration
standards
Interior Design
Air circulation
Location of copy machines
Housekeeping equipment and
product storage
Materials Selection
Fibrous materials
Microbial contamination
Emissions of VOCs
Toxic components
Construction Procedures
Proper installation and
balancing of equipment
The sink effect
IAQ Materials Testing
Paint on gypsum board
Carpet and adhesive
Ceiling tile
Fireproof ing
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
74
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The team established thresholds for the maximum allowable concentrations of
contaminants in the indoor air, based on health effects research and an
understanding of what is possible to achieve in a new building with materials
commonly available in the market. These thresholds were used to screen selected
finishes and as testing criteria for overall indoor air quality in the finished facility. At
the end of construction, ambient air sampling and testing were required to be
performed at 16 locations throughout the office areas of the new EPA facility.
Maximum Indoor Air Concentration Standards
Natural Resource Building,
Olympia, Washington
The Natural Resources Building
(NRB) is a 300,000-square-foot,
six-story office building completed
in Washington state in 1992.
During its design, construction and
commissioning, three steps were
taken to promote good IAQ:
The HVAC system was designed
to the requirements of ASHRAE
62-89
To avoid potential high-emitting
materials in the building, major
materials used in the
construction, finishing and
furnishing of the building were
required to be tested in an
emission test chamber
To allow all materials emissions
to decay, the empty building was
flushed out with 100% outside
air for 90 days prior to
occupancy
Indoor Contaminants
Carbon Monoxide (CO)
Carbon Dioxide (CO2)
Airborne Mold and Mildew
Formaldehyde
Total Volatile Organic Compounds (TVOC)
4 Phenylocyclohexene (4-PC)*"
Total Particulates (PM)
Regulated Pollutants
Other Pollutants
Allowable Air Concentration Levels*
< 9 ppm
< 800 ppm
Simultaneous indoor & outdoor readings
< 20 |lg/m3"
< 200 |lg/m3"
< 3 |lg/m3
< 20 |lg/m3
< NAAQS
<5%ofTLV-TWA""
All levels must be achieved prior to acceptance of building.The levels do not account
for contributions from office furniture, occupants and occupant activity.
Above outside air concentrations.
4-PC is an odorous contaminant constituent in carpets with styrene-butadiene-latex rubber (SBR).
TLV -TWA = Threshold Limit Value -Time Weight Average.
The project team originally specified that all materials used in large quantities with
potential to impact indoor air quality be chamber-tested by the contractor, with
results to be used by EPA to model predicted concentrations of chemicals. Based on
concerns about the cost of this extensive testing program, however, the requirements
were revised to focus on the four materials most commonly exposed to the air in the
building. These four materials were required to be tested as they would be assembled
in the building-paint applied to gypsum wallboard, carpet adhered to concrete,
fireproofing spray on steel, and acoustical ceiling tile.
Construction Procedures
EPA specifications require many of the same lAQ-related construction procedures
that were employed by the Natural Resources Building in Olympia, Washington.
Some changes were made, however, based on the lessons learned in construction of
the Washington project.
Prior to construction, the contractor for the EPA Campus was required to
submit a schedule that described the sequence of material and finish installation.
Construction sequencing recommended that "wet" materials that release indoor air
contaminants as they cure, be applied before the installation of "fuzzy" materials
that absorb airborne contaminants and re-emit them over time. Temporary
ventilation during construction further protected the building from absorbing
contaminants during the construction process. From the time the building was
75
Design Process: Indoor Air Quality
-------
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Generic Schedule Sequence of Finishes
substantially enclosed until occupancy, the building was required to be ventilated
with 100 percent outside air. Any ductwork used during construction was required
to be cleaned prior to occupancy.
The EPA project team used an alternative to the extended 90-day
post-construction flush-out period that was employed by the Natural Resources
Building. Specifications for the EPA Campus required the contractor to ventilate
during construction and perform baseline indoor air quality testing prior to
acceptance to determine whether indoor air concentrations comply with maximum
allowable limits (see chart below). If materials are installed as specified and
What is the "Sink Effect"?
The sink effect refers to the
absorption of chemicals by a
surface, which slowly releases
them into the building atmosphere
over time. Finishes with the
highest accessible surface area
(e.g., "fuzzy" materials such as
carpet, upholstery and ceiling tiles)
per unit mass tend to have the
highest sink effect.
Sequences of
Finish Installation
Wet "off-gassing" materials must
be installed before dry or fuzzy
"sink" materials to the greatest
extent possible.
"Wet" materials include, but are
not limited to: adhesives, sealants,
glazing compounds, particle board
and paint.
"Dry" or fuzzy materials include,
but are not limited to: carpet and
padding, ceiling tiles and fabric-
wrapped acoustical panels.
Predicted TVOC Concentration During 30-Day Flush-Out
1.8.
1.6
DAY 2
10 12 14 16 18 20 22 24 26 28 30
EXPOSURE Model
Modeling courtesy of Jason M. Cortell & Associates
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
What is "Flush-Out"?
Flush-out refers to increased
ventilation to remove, or "flush-
out" contaminants from the
building. Flush-out is best
performed with 100% outside air
that is exhausted directly to the
outside and not recirculated.
Scheduling of flush-outs during
construction, pre-occupancy and
before start-up after the systems
have been down will enhance
indoor air quality.
Why Not "Bake Out"
Running building at high
temperatures post-construction to
"bake" chemicals out could
possibly cause unusual chemical or
biological conditions, and is not
recommended.
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Indoor Air Quality Facility
Operations Manual
Offers guidance for provision
and maintenance of IAQ for the
new EPA Campus during
construction, pre-occupancy and
post-occupancy
Documents the design criteria
employed and major design
decisions made
Describes lAQ-related
construction provisions
including IAQ emissions testing
of materials, sequence of finish
installation, temporary
ventilation, base-line IAQ testing
and commissioning
Contains HVAC equipment
inspection forms, IAQ
management checklist and other
forms
Design Decisions Matrix
Siting of Building
Location of Parking Garages
Laboratory Exhaust Stacks
Radon
Delivery/Loading Zone
Landscaping
Laboratory Fume Hoods
Locate exhaust downwind from
outside air intakes and separate
by more than 100 feet.
Maximize separation between
parking areas and air intakes.
Locate parking structure away
from the building.
Stack height increase to 30' based
on wind tunnel testing.
Site specific testing confirmed
low levels of radon.
Maintain negative pressure in
loading area, positive pressure
in building.
Low maintenance and
non-sporulating plants selected.
Plants used as a barrier for
vehicle exhaust.
Install flow guages and alarms.
Acoustical Insulation of Ducts Ductwork increased in size to
eliminate need for acoustical
insulation. In select areas, mylar
coated silencers are used as
ductwork transitions out of
equipment rooms.
Install drain pans pitched toward
drain pipe.
Moisture Accumulation
Humidity Control
Corrosion Inhibitors
Fireproofing Spray
No moisture carry-over into
system.
Inhibitors do not contain
volatile amines.
Cementitious mix specified for
return air plenum.
Impact on IAQ
Minimizes reentrainment of
laboratory exhaust at air
intakes.
Reduces potential vehicular
exhaust entering the
building.
Reduces the potential for
vehicular exhaust entering
the building
Minimizes reentrainment of
laboratory exhausts into
air intakes.
Confirmed that radon levels
are safe.
Eliminates entrainment of
delivery vehicle exhaust.
Intake of spores, fertilizer or
chemicals entering the
building is reduced.
Minimizes entrainment of
vehicular exhaust.
Provides warning of air
contaminants present in
laboratory areas due to loss
of air flow.
Minimizes potential for release of
fibers into the airstream and
possible contamination of
the HVAC system (duct liners
are difficult to monitor and clean
and can be sites of microbial
contamination).
Reduces moisture, which
could result in introduction
of bacterial contamination
into HVAC system.
Minimizes moisture in HVAC
system and resultant
bacterial contaminants.
Eliminates exposure to
certain air contaminants.
Helps minimize potential for
airborne fibers.
ventilation is provided during construction, the building should pass the test shortly
after the building construction is complete. See the EXPOSURE modeling on the
following page for results of a study indicating the building VOC levels should fall
within the acceptable range about 12 to 14 days after construction is complete. If
limits were not met, the contractor would be required to ventilate the building until
it met the required limits and bear the expense of retesting.
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Design Process: Risk Prevention
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This EXPOSURE model predicted the
concentration of VOC in the indoor air
over a 30-day flush out period beginning after
construction is complete. Furniture was
projected to be installed on the 6th day after
flush-out began, and VOCs reached acceptable
levels by the 14 day. Although this analysis
considered "typical" furniture available from the
marketplace, EPA further extended its IAQ
protections into furniture procurement. The
products in EPAs new offices were, like the
products used during construction, required to
have low VOC and formaldehyde
emissions.The IAQ Facility Operations Manual,
developed by the EPA project team, includes a
design decisions matrix outlining exterior and
interior design components of the new campus
and the impact these decisions had on IAQ.
I '
Key Issues to Consider
Adopt a philosophy of
avoidance toward all risks to
human health and well-being
Predict EMF levels at different
locations in the building;
identify major sources
Increase occupant distance
from major sources of EMF
Modify floor plan to buffer
spaces of regular long-term use
from major EMF sources
Have soils tested for radon if
building is located in a region
where radon occurs
If necessary, incorporate a
radon mitigation system into
the building design
Risk Prevention
Building-related health risks are often difficult to recognize prior to the scientific
discoveries that provide a verifiable link to health effects. However, the high cost of
asbestos and lead remediation has building owners, operators and occupants
thinking carefully about how to avoid exposing themselves to similar financial risk
from other building-related problems in the future. Consequently, the team for the
EPA Campus carefully considered the potential risk associated with electromagnetic
fields (EMFs) and radon gas.
Electromagnetic Fields
The team reviewed available literature on EMFs and their threat to health and
determined that while EMF radiation could be measured, its threat to humans had
not yet been proven or disproved. Nevertheless, the team recommended adopting a
philosophy of prudent avoidance toward EMF risks and undertook modifications of
the building design to reduce occupant exposure.
EMF radiation can be mitigated by distance and by shielding. Distance offers
maximum protection and is "low-tech," while the costs associated with shielding are
high and the results are difficult to measure. Consequently, the design team chose to
create "buffer zones" to reduce prolonged exposures in portions of the building that
are occupied for long periods of time, such as the laboratories and offices.
The largest sources of EMF were identified as the building's transformers, the
electrical rooms with their many cables, and the electrical conduit that was routed
under the building atria. As a first step circulation and utility spaces were used to
maximize the separation between a source and any potential receptors. An analysis
revealed that the conduit under the floor of the atrium would not be problematic
because the time for possible exposure in that circulation space is minimal. However,
the electrical rooms had to be relocated next to restrooms and utility spaces and away
from occupied areas such as offices, laboratories or meeting spaces.
Because EMF radiation diminishes geometrically over distance, the floor of the
main electrical room was lowered so that a separation of at least six feet could be
made between the electrical transformers and building occupants on the office floor
above. Research has shown that EMF exposures are minimal beyond a distance of
six feet from the source.
Electromagnetic Fields (EMFs)
Electric and magnetic fields may
occur alone or in combination and
are a form of non-ionizing
radiation. Electricity flowing in a
wire or being used in an appliance
creates electric and magnetic
fields around them, as do power
lines and electrical equipment
used in commercial buildings.
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
78
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Radon Prevention
Measures Commonly
Used in Commercial
Buildings
Active soil depressurization
Pressurization of the building
using the HVAC system
Sealing all major radon entry
routes
Key Issues
Design in modules to minimize
construction waste
Develop construction waste
recycling plan, including salvage
of existing construction
materials
Mulch landscape debris and
other organic waste on site,
both during construction and
occupancy
Develop hazardous materials
management plan for both
construction and occupancy
Develop a recyclable materials
collection system for building
users
Minimize the amount of
building to be built
Consider renovation and reuse
as alternatives to new
construction
Focus on adaptability of
structures
Radon Gas
Radon is a colorless, odorless radioactive gas produced by the radioactive decay of
radium-226, an element found in varying concentrations in many soils and bedrock.
As a gas, radon can easily move through small spaces between particles of soil and thus
enter a building, reaching levels many times higher than outdoor levels.
Radon levels are usually measured in picocuries per liter of air (pCi/L). It is
currently recommended that radon levels be reduced to less than 4 pCi/L, if not as
close to ambient levels as feasible (0.4 pCi/L). The radiation released by the decay of
radon isotopes can damage lung tissue and can increase one's risk of developing lung
cancer. The health risk depends upon both the levels and the length of exposure to
radon decay products.
Radon typically enters a building from the soil through pressure-driven transport,
where the conditions in the building draw air up and into an opening. Radon can
also enter a building through diffusion, well water and construction materials.
While radon mitigation is an issue that most people associate with residential
construction, the risks for commercial building occupants are real. Because radon
gas is naturally occurring in the soils of some portions of North Carolina, EPA
believed that it was prudent to have its site tested for radon gas. While EPA was
prepared to take action if necessary, the tests proved that radon was not present on
the site and that no mitigation was needed.
Waste Management
The EPA Campus is designed to optimize waste management opportunities during
design, construction and operation. Waste management occurs on many levels,
beginning with efficient use of resources, a design approach that maximizes building
longevity, and a thorough and systematic approach to reuse, recycling and
responsible disposal of waste materials.
Efficient Building Design
Efficient building design conserves resources and reduces waste through design
efficiencies. This issue is important when considering space planning efficiencies as
well as volume, which standard net-to-gross calculations often overlook. For
example, "interstitial" planning is a common strategy for providing services to
laboratory areas. This approach requires extra ceiling height above the lab space
through which services are routed. The overall effect is that the floor-to-floor height
is boosted by as much as five to six feet in all lab areas, as well as in office areas that
fall within the laboratory block in order to accommodate the necessary services.
After reviewing the options, the EPA project team chose to make use of a service
corridor to deliver utilities and accommodate future changes. As a result, the overall
height of the building and total building volume was reduced, material
consumption was lowered and access to the utilities was enhanced.
Waste Reduction
Modular design that is coordinated with standard building material dimensions can
greatly reduce waste from trimming. Consequently, standard-size building materials
were used wherever possible in the design and detailing of the EPA facility to
minimize waste in manufacture and installation. Use of standard slopes for tapered
roof insulation, for example, decreases waste by as much as 50 percent.
Increased Building Longevity
While it is common in the design and construction industry to design for a 30-year
life cycle with cost paybacks limited to a three-five year time frame, EPA has a long-
79
Design Process: Waste Management
-------
term interest in this facility. In addition, the project team recognized that the actual
use of a building often exceeds the projected design timeframes requiring extensive
refurbishments and maintenance. To address these issues within the context of
sustainability, the new facility was conceived as a "100-year" building and designed
accordingly. Key elements like the facility's structure, the cladding, the flashing and
the fireproofing are intended to survive with minimum repair for the projected life.
The overall consequences of the extended design are a reduction in materials usage
and the increased adaptability over the life cycle of the building.
Building Adaptability
Designing for adaptability is important because even if a building's physical
structure is long-lived, overly specific building designs that cannot adapt to
changing needs can become obsolete before their time. Ample ceiling height, a
generous column bay and good access to daylight make the EPA facility an easily
adaptable structure. Provisions have been made to accommodate growth of
laboratory programs within the laboratory block itself. Approximately 20 percent of
the space in the laboratory buildings is occupied by offices. This office space is
convenient for lab workers but also serves as a built-in buffer for growth. If office
space needs grow and lab needs shrink, more offices can be accommodated in the
lab building. This "swing space" was important to creating a flexible facility design.
Collection and Handling of Recyclables
The EPA Campus has been designed to accommodate the recycling of paper, glass,
aluminum, plastic and cardboard. Convenient collection locations have been
provided near areas that generate large quantities of recyclable waste (such as copy
rooms and galleys). These areas are located near elevators to aid collection.
Consequently, collection areas were located in copy rooms and building break
rooms where the majority of recyclables will be generated. In addition, the break
rooms were located directly adjacent to the service elevator lobby, and the copy
rooms were less than 50 feet away. The service elevator is used by janitorial staff to
transport the recyclables to the loading dock via an underground service tunnel that
moves material on electric carts. This means that recyclables can be transported to
the staging area at the loading dock without having to pass through any public
areas. The loading dock has been designed with ample room for staging of
recyclables before pickup, and a compactor for cardboard has been provided.
Recycling and waste reduction is well integrated into the cafeteria design as well.
Reusable china and flatware will be used in the cafeteria. Recycling collection areas
will be built into the tray drop area in the cafeteria, and the vending areas. An
organic waste recycler will be used for pre- and post-consumer compostables from
food service.
Recycling Chutes
Recycling chutes are vertical shaftways that allow recyclables to be dropped to a
collection area below. Chutes were initially evaluated for the EPA facility, with the
service corridor acting as a lower-level zone to manage collection. Unfortunately,
recycling chutes are most efficient in predominantly vertical buildings where
relatively closely spaced chutes can accommodate occupants. However, in the five-
story, approximately quarter-mile long floor plan of the EPA facility, recycling
chutes were a costly and redundant vertical transport system that would have
become a maintenance burden. Recycling chutes can also become maintenance
problems if the wrong wastes are sent through. For example, sticky residue from soft
drinks can attract pests or promote the growth of bacteria and mold. Instead,
recycling containers were located near elevators, and the underground service tunnel
was used to provide direct access to the loading dock.
Flexible Laboratory
Plan of typical floor circulation flow
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
80
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Cover of WasteSpec,
published 1995
Reuse of On-Site Materials
All material generated on the site from land-clearing activity and excavation is
reused on site. Land-clearing debris remaining after the valuable materials have been
sold as timber is shredded for use as mulch. The excess material is composted with
topsoil as a soil amendment. Excavated topsoil is being stockpiled for reuse and
excavated rock is crushed for use as structural fill.
Construction Waste Recvclino
Construction waste occupies about 25 percent of the space at municipal landfills in
the United States. To reduce the demand on landfills, construction and demolition
waste landfills were created to offer a lower cost alternative to municipal landfilling
for the construction industry. Debris that is essentially clean and inert can be
dumped for a lesser fee than municipal waste because the landfill does not
require a liner.
Three basic types of construction waste recycling are on-site separation,
phase-based sorting by hauler and off-site sorting of mixed waste. Before developing
a specification, research should include landfill and recycling tipping fees and the
availability of recycling companies that will accept recyclable material. WasteSpec is
a model waste specification that was created by the Triangle J Council of
Governments in Research Triangle Park. The information applies to all parts of the
country and a resource list in the appendix provides names and contact phone
numbers for recycling coordinators for all 50 states, the Canadian provinces,
Washington, D.C. and Puerto Rico.
CONSTRUCTION WASTE MATERIALS
SPECIFIED FOR RECYCLING
1 Land clearing debris: Solid waste generated solely from land
clearing operations, such as stumps and trees
2 Concrete, masonry and other inert fill material: Concrete,
brick, rock, clean soil not intended for other on-site use, broken
asphalt pavement containing no ABC stone, clay concrete, and other
inert material
3 Metals: Metal scrap including iron, steel, copper, brass and aluminum.
4 Untreated wood: Unpainted, untreated dimensional lumber,
plywood, oriented strand board, masonite, particleboard and wood
shipping pallets
5 Gypsum wallboard scrap: Excess drywall construction materials
including cuttings, other scrap and excess material
6 Salvaged Materials: Reusable lumber, fixtures and building supplies
7 Cardboard: Clean, corrugated cardboard such as used for
packaging, etc.
8 Paper: Discarded office refuse such as unwanted files,
correspondence, etc.
9 Plastic buckets: Containers for various liquid and semi-solid or
viscous construction materials and compounds
10 Beverage containers: Aluminum, glass and plastic containers
81
Design Process: Waste Management
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The EPA project team chose to use on-site separation because clean separated
recyclables have the highest value and many haulers will collect the separated
material in the RTF area. The EPA Construction Waste specification lists materials
recycled and requires the contractor to develop a construction waste management
plan to be approved prior to the start of construction.
Gypsum Grinding
Gypsum can be problematic in landfills because it forms hydrogen sulfide gas under
anaerobic conditions. The best way to solve the problem is through recycling and
keeping the gypsum out of landfills. North Carolina's RTF area is one of the few
regions in the country with an active gypsum recycling industry. The recycled
material is not being reformed into gypsum at this time, but it is being made into
chemical absorbents such as those used in cat litter. Gypsum also makes an excellent
soil amendment if it is ground finely and used in the proper quantities.
The EPA Construction Waste specification gives the contractor the option of
recycling gypsum or grinding it for use on the site. For on-site application as a soil
amendment, 50 pounds per 1,000 square feet, or approximately one ton per acre, of
material ground to a fine particle size can be incorporated into the soil surface. This
quantity can be increased if a soil analysis is reviewed by and approval granted from
the Solid Waste section of the North Carolina Department of Environment and
Natural Resources.
Construction
Most construction processes impact the building site and beyond through
excavation and related soil erosion, disruption of vegetation, wildlife habitat and
topography, compaction of the soil from transportation onto the site, drainage into
nearby water bodies, and even contamination of the site by hazardous materials
when not properly controlled. Other environmental issues include construction
waste, energy used during the construction processes and the effects of material
installation on building indoor air quality.
The impact of these construction processes can be minimized through the creation
and implementation of effective construction management plans, including rigorous
employee education. Just as important, the general contractor should join the team
as a partner with a stake in meeting the environmental goals of the project.
Groundbreaking ceremony, October 1997
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina 82
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Plant rescue
Plant rescue
Partnering for Construction
Prior to construction, EPA and the General Services Administration (GSA) held a
partnering session with the general contractor and AYE representatives involved in
construction administration. Typical partnering focuses on safety, quality, schedule
and budget. For the EPA project, the environment was placed on equal footing. The
environmental goals for the project were discussed and a training video on
environmentally friendly construction practices was shown. This training video,
produced in both English and Spanish, became required viewing for every
construction worker on site.
The video describes the broad range of environmental initiatives included in the
project, including environmentally preferable material specifications, tree protection,
top soil preservation, construction practices to limit potential for contamination of
future indoor air quality, and waste separation and recycling. Site workers and
managers learned not just what is expected of them but why it is important, in the
hope of enlisting each of them as willing partners in the creation of an
environmentally friendly construction site. During clearing, grading and concrete
production, no material left the site as waste, signaling successful reduction and
reuse of materials.
Plant Rescue
While every effort was made to minimize the amount of land that had to be cleared
for the project, EPA utilized plant rescues to help limit the impact of clearing by
physically relocating plant material away from the construction limits before it was
destroyed. A plant rescue involves volunteers entering an area slated for clearing, in
this case the project site, to remove plants that otherwise will be bulldozed during
the construction.
A delay in project start-up from winter 1996 to early summer 1997 afforded the
perfect window of opportunity for a plant rescue operation, as spring is the ideal
time to transplant native plants to maximize their chances for survival. Together
with their neighbors, the National Institutes for Environmental Health Sciences
(NIEHS), with help from the North Carolina Botanical Gardens at Chapel Hill,
EPA saved more than 3,500 plants during several weekends in April and May 1997.
Many plants were transplanted to the NIEHS Campus by volunteer employees to
enrich the wooded understory in front of the NIEHS main building. The rest of the
plants were donated to the Botanical Gardens and relocated by volunteers to public
and private gardens in the area.
Reuse of Land-Clearing Debris
Land clearing generates enormous quantities of biodegradable and potentially useful
organic material, none of which need be lost to landfills. During the clearing of the
EPA site, the contractor successfully salvaged all cleared timber for either sawlogs or
pulpwood, highlighting the usefulness of precious wood resources. The remaining
woody debris was ground into mulch. Often the topsoil and mulch were mixed to
facilitate composting of the mulch and amending the topsoil for future use on the site.
Limbs, stumps and other debris resulting from the site clearing operation was
stacked up ready to be ground into mulch by portable tub grinders. With
conventional construction, piles like these would be burned on the site, and the
stumps would be hauled to a local landfill. On the EPA project, none of the clearing
and grubbing wastes were disposed of off site, and no burning was allowed.
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Design Process: CONSTRUCTION
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Land-clearing debris
Rock Crushing
In addition to the reuse of plant material from the construction site, reuse of
excavated soil and rock from excavation debris reduces both material waste and
transportation from hauling off-site. The contractor has used portable rock
crushers on site to process rock from site excavations as well as scrap concrete, later
in construction. There are two machines: the first is the actual crusher, which
takes rocks up to 24" diameter and discharges material smaller than 3". The
second machine is the sieve and screen, which takes the crusher product and
separates the unwanted gradations and fractions to produce specific aggregates.
Although the excavated rock and weathered rock may not be durable enough to
use as road aggregate, the contractor has used the product in his structural fills and
backfill throughout the site. The aggregate material produced on site has been
used for temporary haul roads and access during inclement weather. To date, the
contractor has not hauled any rock waste from the project.
Debris grinding with tub grinder
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
84
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Rock crusher
On-Site Concrete Batch Plant
The construction contract offered the contractor the option to erect an on-site
plant, provided it would require no additional clearing. An on-site plant was
chosen due to economics and control over the supply. A portable concrete batch
plant was erected on the site, in the south surface lot for the National Computer
Center. One of the contractor's first activities was to rough grade this parking lot,
the largest surface lot in the project, to prepare it for the batch plant.
Tremendous environmental benefits are realized by this decision, including the
elimination of an estimated 75,000 highway miles of concrete transit truck traffic
and a savings of 10,000 gallons of fuel.
On-site concrete batch plant
RotoReclaimer
The RotoReclaimer is a device installed at the concrete batch plant to eliminate
concrete delivery truck washout wastes. The system is a prefabricated unit consisting
of a rotating drum, conveyors and settling tanks. The entire process is self contained
and generates no wastes. Like the batch plant itself, this device was not required by
the contract but was something the contractor chose to employ. The environmental
benefits of the decision, however, are apparent regardless of the motive.
Design Process: Construction
-------
The RotoReclaimer collects wastewater from the concrete mixer to wash and
separate aggregate.
When an empty concrete transit mixer returns to the plant from the placement, its
ramp is backed up to the stand pipe to be washed out. The RotoReclaimer pumps
the reclaimed water into the truck mixer drum to clean it out. The waste slurry is
then dumped into the center of the rotating drum of the RotoReclaimer, where it
is washed and the fine and coarse aggregates are separated. The cleaned aggregates
exit the device on two conveyors and are collected in stockpiles for reuse in the
batching operation. The wash water is pumped into a series of three holding tanks
where it settles to allow the cement to settle out. Clean water is recovered from the
final tank and returned to the system to wash the next truck. Periodically, the
settling tanks are allowed to dry and the solids are cleaned out to be processed
through the rock crusher with the site rock and then reused.
Salvage of Demolition Materials for Reuse
New construction rarely addresses the reuse of salvaged materials, an important
waste-reduction strategy. At the central utility plant, the existing precast concrete
panels on the south walls had to be removed to make room for the plant
expansion. The contractor removed the panels intact, loaded them directly to a
Dismantling precast concrete panels for reuse in plant expansion
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
86
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waiting flatbed truck and stored them on the site to reinstall, where possible, on
the expanded plant. This action saves materials, fabrication, delivery, and disposal
costs compared with traditional demolition and replacement.
Construction Waste Recycling
Using aggressive programs to separate wastes at their sources, the contractors
recovered 80% of the waste generated on site. Including site preparation wastes,
this amounted to about 20 million pounds of resource material that would
normally have been sent as "waste" to landfills. Separate waste hoppers were
provided for drywall, metal, cardboard, wood and other wastes in the buildings
and special crews hauled the hoppers to specially-marked dumpsters. Routine
visual checks ensured that recycling haulers would leave the site with
uncontaminated loads
Use of Recycled Content Building Materials
While minimum recycled content requirements were specified for many
construction materials, good partnering for construction has led to materials with
even better recycled content than originally specified. Recognizing the
environmental goals of the project, the general contractor has searched for and
found some materials with higher recycled content than the minimums required
in the specification. For example, all rebar is made from a mill that uses the
electric arc process, a process that utilizes 100 percent recycled scrap steel.
Another instance in which the general contractor volunteered additional use of
recycled content was for the roadway base course. The use of a minimum of 20
percent recycled concrete aggregate was originally specified for the roadway base
course, however the requirement was one of a few environmental specifications
deleted when the project went out for rebid. Zero aggregate base course was used
due to the unavailability of local waste materials of acceptable quality and
gradation. Now that the project is under construction, however, the general
contractor has volunteered to use 100 percent crushed concrete scrap for the base
course when salvaged material is available.
Submittals Review During Construction
Review of submittals is a particularly important step in the construction process.
Submittal packets were compiled by the various subcontractors and sent to the
project team by the general contractor, often including substitutions to the
products specified. Environmental and other specifications must be tracked by the
architects to avoid getting lost in the process and defeating the team's efforts in the
final stages of the project.
In the EPA Campus, for example, the main building's specifications clearly listed
volatile organic compound (VOC) limits for paint products as well as prohibited
hazardous substances, for which certification of compliance was required. Yet in
the various paint submittal packets received, many of the substitutions included
clearly non-compliant products. Midway it was discovered that the paint
subcontractor did not have a copy of the environmental criteria. Individual
substitutions were rejected based upon noncompliance with these criteria until full
compliance, with little exception, was achieved-a process that took over six
months. This illustrates the importance of maintaining a consistent level of
attention to the integrity of the specifications, particularly for environmental
criteria which are less familiar to many of the parties involved.
o / Design Process: Construction
-------
Constant Vigilance
Through close attention to detail at every step of the process, the project team
has seen most of the environmental design goals of the new EPA campus come to
fruition. And for every small detail that has not ultimately materialized, there have
been new, unexpected environmental gains such as the voluntary concrete
recycling program offered by the contractor. The key to this success has been the
commitment by all parties to the common goals of high quality, cost-effectiveness,
and environmental stewardship.
As the chapters of design and construction draw to a close, and operations begin,
EPA continues its commitment to make this a model, sustainable campus-still
climbing the greening curve.
The Greening Curve: Lessons Learned in the Design of the New EPA Campus in North Carolina
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EN )TES
Our Common Future: The World Commission on Environment and
Development, Chaired by Gro Harlem Brundtland of Norway,
Oxford University Press, New York, 1987.
David Malin Roodman and Nicholas Lenssen, A Building Revolution: How
Ecology and Health Concerns are Transforming Construction, WorldWatch
Paper 124, WorldWatch Institute, Washington, DC, March 1995; and the
U.S. EPA solid waste program.
Lester R. Brown et. al., State of the World, Making Better Buildings,
page 95. (chapter by Nicholas Lenssen and David Malin Roodman)
WW Norton & Company, New York, NY, 1995.
Report to Congress on Indoor Air Quality, Volume II:Assessment and Control of
Indoor Air Pollution, U.S. Environmental Protection Agency (EPA), Office of
Air and Radiation (OAR), (Washington, DC, 1989).
The Trane Company, Trane Air Conditioning Economics (TRACE), an
analytical tool enabling building system designers to optimize the
building, system and equipment designs on the basis of energy utilization
and life cycle cost.
Lumen Micro, Lighting Technologies Inc., software that provides tools to
create, simulate and analyze lighting layouts for both indoor and outdoor
applications.
Sparks, L.E.; Exposure Version 2:A Computer Model for Analyzing the
Effects of Indoor Air Pollutant Sources on Individual Exposure,
EPA-600/8-91-013 (NTIS PB91-507764). Air Pollution Prevention and
Control Division, Research Triangle Park, NC, April 1991.
Note:The Exposure model has been replaced with a new model called RISK.
David Malin Roodman and Nicholas Lenssen,^ Building Revolution:
How Ecology and Health Concerns Are Tranforming Construction,
WorldWatch paper 124, page 23. (Washington, DC: WorldWatch Institute,
March 1995. Library of Congress number 95-060295).
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To obtain a copy of "The Greening Curve" contact:
U.S. Environmental Protection Agency
Office of Administration and Resources Mgmt.
MD-C-604-05
Research Triangle Park, NC 27711
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