Using Recycled Industrial
Materials in Buildings
Greening the built environment. THIS information
sheet discusses the use of recycled industrial materials in buildings as an
alternative to virgin materials and building products. Industrial materials are the
byproducts of industrial processes. Each year in the United States, industries
produce over half a billion tons of residuals that are potentially usable materials,
such as coal combustion products (CCPs), construction and demolition (C&D)
materials, spent foundry sand, used tires, and slags. Many of these materials
have chemical and physical properties that make them valuable resources when
recycled or beneficially reused, but they are often disposed of as waste. The
U.S. Environmental Protection Agency (EPA) is committed to increasing the
recycling of industrial materials as part of its Resource Conservation Challenge,
a national effort to conserve energy and other resources and reduce greenhouse
gas emissions by managing materials more efficiently. Industrial materials
recycling (IMR) helps accomplish these goals by conserving natural resources and
decreasing energy use and greenhouse gas emissions.
www.epa.gov/industrialmaterials
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Why Use Industrial
Materials in Buildings?
Environmental Benefits
An Overview:
Since many industrial materials are used to replace non-renewable
virgin materials that must be mined and processed for use, IMR
conserves natural resources and reduces the energy use and pollution
associated with these activities. For example, substituting coal fly ash
(an industrial material) for portland cement in concrete saves the energy
and greenhouse gas emissions associated with producing cement. The
beneficial use of industrial materials results in less material being sent
to disposal facilities, which saves landfill space and further reduces
greenhouse gas emissions and other pollutants.
Economic Benefits
Industrial materials are often less expensive than virgin materials,
so they make good economic sense for builders and project owners.
Further, reusing or recycling C&D materials onsite can reduce material
hauling and disposal costs. These savings, applied to the total project
cost, make it possible to do more work with the same budget. In
addition, C&D recyclers will often charge less to accept recyclable
materials that have already been separated from non-recyclable
materials-a practice that can be encouraged at the building site by
using separate containers for various materials.
Performance Benefits
Some industrial materials, such as fly ash and slag
cement used as supplementary cementitious material
in concrete, offer significant performance benefits
over virgin materials. Other industrial materials, such as
foundry sand, perform just as well as—and in some cases
better than—virgin materials in building applications. Coal
bottom ash used as bedding material for green roofs is lighter-
weight than alternatives, an important quality in this application.
Tire shreds can not only provide more effective drainage around
building foundations due to a greater gap structure relative to gravel and
dirt alternatives, but also put less pressure on building foundation walls
compared to the denser and heavier materials that are sometimes used.
Green Building
Green, or sustainable, building is the practice of creating and using
healthier and more resource-efficient methods of construction,
renovation, operation, maintenance, and demolition. Designing with
industrial materials and recycling C&D materials generated from projects
leads to more sustainable buildings. Most green building certifications
give points for these practices, two of the best-known certification
systems are the U.S. Green Building Council's Leadership in Energy and
Environmental Design (LEED)® green building rating system and the
Green Building Initiative's Green Globes™ green building rating system.
Building Applications
for Industrial Materials
This diagram illustrates a variety of common building applications
for industrial materials. Note that the availability of specific
industrial materials can vary regionally. The websites in the
"Resources for More Information" section of this document may
provide information on identifying suppliers of industrial materials
in your region as well as local C&D materials recyclers.
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1 ) ( 2 ) Green Roofs & Landscaping
Green roofs are roofs covered with plants, they
reduce storm runoff and provide insulation.
Scrap tires can be used to make rubber tile
for walkways. Bottom ash can be used as
bedding material. Clean wood, recycled gypsum
wallboard, and cardboard can be ground and
used as soil amendments in both green roofs and
landscaping applications.
Landscape Furniture
Benches can be made with plastic lumber
containing fly ash or with recycled C&D wood.
Building Facing Material
Manufactured stone, which is concrete mixed
with aggregates, is commonly used as building
facing material. Fly ash can be used in the
production of manufactured stone.
$) Sidewalks
Industrial materials can be used to make concrete
sidewalks, and used tires can be recycled to
create rubberized sidewalks. Asphalt concrete
sidewalks can be made with recycled asphalt
pavement and recycled asphalt shingles.
fiJ Ceiling Tile
Ceiling tile can contain flue gas desulfurization
(FGD) gypsum (a material resulting from burning
coal to produce electricity), fly ash, recycled
gypsum wallboard, or air-cooled blast furnace slag.
Flooring
Industrial materials can be used in various
flooring applications.
(7a) Carpet backing: Used tires, fly ash, or
recycled carpet.
Wood flooring: Salvaged lumber or
recycled wood.
Tc Flooring tile: Fly ash, blast furnace slag.
7d Tile underlayment: Fly ash
Backfill (Foundation Support)
Backfill surrounds the building foundation,
supporting it and providing drainage. Scrap
tires provide superior drainage, insulation, and
wall pressure relief. Blast furnace slag and
recycled concrete also can be used
for drainage.
sure to consult state and local environmental
agencies to determine approved uses of
industrial materials.
(SJ Foundation Structural Fill
Structural fill is an engineered fill that is
constructed in layers and compacted to a desired
density. Coal fly ash, bottom ash, slag, and
spent foundry sand can all be used as structural
fill. Concrete can be crushed and used onsite as
structural fill.
HIM Poured Concrete Foundation
Concrete, which is composed of cement,
aggregate, and water, is used in a wide array of
building applications. Industrial materials can be
recycled in cement and concrete in many ways.
Here are a few examples:
• Fly ash and ground granulated blast
furnace slag can be used as partial cement
replacements. Using these materials can
produce stronger, longer-lasting concrete.
« Portland cement itself can be made with fly
ash, FGD gypsum, foundry sand, recycled
gypsum wallboard, blast furnace, and steel slag.
• Concrete aggregates can include bottom ash,
foundry sand, crushed concrete, and blast
furnace slag.
rrn Insulation
Air-cooled blast furnace slag can be used to
produce mineral or rock wool insulation (also
known as slag wool insulation).
(u) Drywall/Wallboard
FGD gypsum and recycled gypsum wall board can
be used to manufacture drywall.
m) Mortars, Grouts, Stucco
Mortars, grouts, and stucco contain aggregate
(sand), binder, and water. Fly ash, foundry sand,
silica fume, and slag cement can all be used as
partial cement replacements.
M4y Masonry Blocks
Masonry blocks are made from cement and
aggregate. Slag cement, fly ash, or silica fume can
substitute partially for cement. Bottom ash, blast
furnace slag, and recycled concrete aggregate can
substitute for newly mined materials.
Msn Base Material
Spent foundry sand can be used in place of
natural soil as base material for the building site.
In cold weather climates, this strategy can extend
the construction season because foundry sands
do not freeze as readily as most soils. Becycled
concrete is also commonly used as base material.
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Case Stud
EPA Potomac Yards
Buildings Maximize the
Use of Recyclable Materials
The EPA buildings at One and Two Potomac Yard, located in Arlington,
Virginia, are prime examples of how buildings can be constructed with
resource management in mind. The buildings are U.S. Green Building Council
LEED® Gold certified and contain, on average, 27% recycled content (as per
LEED® calculations). Environmentally preferable products used in the buildings
include slag concrete aggregate, fly ash, certified hardwood and softwood
building products, recycled-content ceiling panels, carpet tile, and gypsum
wallboard. Portions of the below-grade, poured-in-place concrete structure
used 35% recycled-content concrete. This concrete contained approximately
670,000 pounds of slag for aggregate. Further, fly ash was used in concrete
masonry unit blocks.
Prior to construction, the project team developed a C&D materials
management plan. This included tracking the amount of C&D materials
diverted from landfill disposal once construction commenced. The major
groups of recycled materials were wood, steel, concrete, asphalt, and
concrete masonry units, cardboard and paper, and dry wall. An estimated
71 % (about 2,000 tons) of the C&D materials generated during the
construction of One and Two Potomac Yard was diverted from landfills. The
majority of these materials were separated in material-specific dumpsters at
the jobsite, which were then taken to C&D recyclers.
The project won several awards for its green design, including the 2007
White House Closing the Circle Award, a 2007 award for best environmentally
responsible building from the Northern Virginia Chapter of the National
Association of Industrial and Office Properties, a 2005 Green ABBIE Award
from the Arlington Economic Development Commission and Arlington Chamber
of Commerce, and the U.S. General Services Administration (GSA) Lease
Project of the Year Award (2004).
Did You Know?
The American Society for Testing
Materials (ASTM) has studied and
evaluated the benefits of using industrial
materials in civil engineering applications.
ASTM C 150, ASTM C 311, ASTM C
595, ASTM C 618, and ASTM C 989
are standard specifications for using
fly ash and ground granulated blast
furnace slag in cement and concrete
in buildings. ASTM D6270-98 provides
design guidelines for using scrap tires in
civil engineering applications. Be sure to
contact your state and local environmental
agencies for more information about
approved uses of industrial materials. See
the ASTM website at: www.astm.org
Resources for More Information
EPA's Industrial Materials Recycling Homepage:
Provides an overview of industrial materials, their
benefits, and opportunities for reuse and recycling:
www.epa.gov/industrialmaterials
EPA's Comprehensive Procurement Guidelines
(CPG): Offers information about construction,
landscaping, and other products containing
recycled content. Though designed for
procuring agencies using federal funds, these
guidelines are also useful for the private sector:
www.epa.gov/cpg
Construction Industry Compliance Assistance
(CICA) Center: Contains a C&D materials
State Besource Locator, where you can
find state environmental agency Web sites:
www.cicacenter.org
U.S. Environmental Protection Agency
EPA530-F-08-022
www.epa.gov
October 2008
^ Recycled/Recyclable —Printed on paper that contains at least 50% post consumer fiber.
Industrial Resources Council (IRC): The IBC
is composed of industry trade associations
representing coal combustion products, foundry
sands, iron and steel slag, wood and pulp
materials, rubber materials, and C&D materials.
This Web site contains information about
industrial materials and their applications:
www.industrialresourcescouncil.org
The University of North Dakota's "Buyer's
Guide for Coal Ash-containing Products":
Provides links to suppliers of building materials
containing coal combustion products:
www.undeerc.org/carrc/BuyersGuide
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