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					Green Building Materials & Products

           Lecture 4
    Green Building Materials

 Materials-related impacts
 “Green” building materials
 No perfect material
 Decision-making criteria
 Examples of “green” materials
 Issues related to “green” materials
 Future of “green” materials
          Environmental Risks (US EPA)

         HIGH                    MEDIUM                        LOW

Habitat                   Herbicides/pesticides   Oil spills
alteration/destruction

Species extinction/loss   Toxics/nutrients/BOD/tu Groundwater pollution
of biodiversity           rbidity in surface waters

Stratospheric ozone       Acid deposition         Acid runoff to surface
depletion                                         waters

Global climate change     Airborne toxics         Thermal pollution
Building Materials
Waste Quantities


     Construction
    and Demolition        Other Waste
        Waste                 66%
         34%

   136 Million
      tons


                     259 Million
                        tons
 Waste Quantities

                                         N ew
                                    C o ns t ruc t io n
                                           8%




              Construction
                   and
Other Waste    Demolition                                 Demoliton
                 Waste                                      48%
   66%
                             Renovation
259 million       34%
                                44%
   tons        136 million
                  tons
            Waste Quantities
Construction and Demolition
Waste

                      New
                   Construction
                       8%




                                  Demoliton                 Residential
                                    48%
                                                               30%
      Renovation
         44%




                                                 Non
                                              Residential
                                                 70%
                                                Residential
Waste Quantities                                Demolition
                       Roofing
             Insulation Waste
                4%       4%
       Drywall
         4%
                                                      National
                                                      Case
   Wood
    5%

                                     Concrete
                                       29%
                                                      study
 Plywood
    8%                                                average


    Dimensional
      Lumber
       17%
                                 Metal
                                 29%
                                                      Commercial
    Waste Quantities                                  Demolition

               Wood 16%

                          Landfill Debris 9%



                                 Scrap Iron 5%

                                   Asphalt 2%
                                   Brick 1%
                                   Roofing 1%




Concrete 66%
                              Sample Composition of Commercial Demolition Debris (19
                              projects in the Pacific Northwest, R.W. Rhine, Inc., Tacoma,
                              Washington (Franklin Associates, 1998)).
   Demolition Waste Generation Rates


                              Waste Produced
Construction Type
                              ( lbs / SF )

Non Residential Demolition    38 - 358

Residential Demolition        50 – 115

Residential Renovation        3.31 – 72.10

            Vary depending on construction type
                  Waste Quantities
Construction and Demolition
Waste



      Demoliton            Renovation
        48%                   44%

                                           Non
                                        Residential
               New
                                           47%
            Construction
                8%
                                                      Residential
                                                         53%
                                                      Residential
       Waste Quantities                               Renovation


                    Dryw all 21%



Roofing 28%


                                   Miscellaneous 6%

                                   Metals 1%




              Wood 44%
                              Sample Composition of Residential Renovation Debris (Average
                              of two sites, METRO Portland, Oregon, (Franklin Associates,
                              1998)).
Waste Quantities


      Renovation
         44%


                       New
                    Construction
                        8%




       Demolition
         48%
    Waste from Construction

   Material                Tons            Percent of total
   Wood                    3.40            46
   Gypsum / drywall        1.88            25
   Mixed debris            1.13            15
   Cardboard               0.40              5
   Metals                  0.44              6
   Masonry                 0.18              2
   Total                           7.43
   Waste generated              7.2lbs/SF
   Construction Waste from a 2,060 sq. ft. Single Family
    Home
    World Wastes, June, 1994.
Embodied Energy of Materials

   Material                Btu/Lb
   Gravel, stone           7-9
   Lumber                  250
   Concrete                667
   Paint                   4,288 - 6,514
   Glass                   8,852 - 9,743
   Steel, lead             10,188 - 18,730
   Polyethylene, plastic   37,323 - 68,840
   Aluminum                82,368 - 100,235
      Intensity of Materials Use
     CO2 Emissions          Air Pollution        Embodied Energy
1.    4” brick veneer        16g alum            4” brick veneer
2.    24g porcelain steel    18g alum            4” conc 5,000 psi
3.    22g steel deck         22g steel deck      8” CMU wall
4.    18g alum               6” 20g std/24” oc   6” 22g std/16”oc
5.    ¼” clear glass         ¼” clear glass      6” 22g std/24”oc
6.    ½” gypsum bd           ½” gypsum bd         Acrylic stucco (2)
7.    6” fiberglass           6” fiberglass       EPS 1”
8.    2x6/16” oc              2x6/16” oc          ½” gypsum board
9.    2x6/24” oc              2x6/24” oc          6” fiberglass
Relative impacts: per SF- highest to lowest
       Issues and Conflicts

   Which is worse: a product that pollutes the
    air by consuming energy from coal-fired
    power plants or one that disrupts
    ecosystems by consuming energy from
    massive hydroelectric dam projects?
     Characteristics of Green Materials

 Minimize negative impact on future generations
 Non-toxic, does no harm to occupants and environment
 Local
 Natural
 Low tech
    Concrete

 Cement, water, and aggregate
 Stone aggregate 48%
 Sand 34%
 Portland cement 12%
 Water 6%
     Cement
 Cement - lime, silica, iron and alumina + gypsum
 Lime 60-66%
 Silica, 19-25%
 Alumina 3-8%
 Magnesia 0-5%
 Ferric oxide 1-5%
 0.64 to 1.25 lb. of CO2 per lb. of cement
 Strip mining - bauxite ore, sand, aggregate
       Green Concrete - Fly-Ash
   Substitute 15%-25% of cement
   Maximum 40%-50% of cement
   Improves workability, reduces water requirements,
    increases the strength, reduces permeability and
    corrosion
   Fly-ash SO2 possible toxicity for interior
   Curing time 72 vs. 28 days
   Increased strength 10-15%
   Less cement per unit volume and less concrete per
    load per square inch
         QUESTION?
   Steel Stud                      Wood Stud
•Steel Most recycled             •Wood can be recycled or
material                         downcycled
•NON RENEWABLE                   •Potentially Renewable
RESOURCE                         Resource
                                 •Learning curve for
•Potential yield strength        installation complete
problems in fires
                                 •Material grading and
•Thermal Transfer                behavior established

      Environmental Issues often difficult to Quantify
          Forest Issues - General
   55% of wood is used for fuel, remainder for lumber, paper,
    other industrial products
   Legal forest products; $142 billion/yr
   Consumption per capita 12x greater in industrial countries
    compared to developing countries
   Wood production is now more efficient (23% 1945-1990)
   Wood consumption per capita in US declined by 52% since
    1990
   New products: OSB, particleboard, I-joists use less wood
    and more efficiently
         Wood in Construction
   US: 40% of roundwood used in construction
   10% of world’s wood supply used in US construction
   Home area per capita in US increased 79% in last three
    decades
   During construction 10% of wood ends up as waste in the US
   New framing methods (Optimum Value Engineering) can
    reduce wood use and waste by 20%
   Salvaged wood can be very valuable
   Certified wood: Smartwood (Forestry Stewardship Council)
    protects forests
         Needed Changes
   Use certified wood or salvaged lumber
   End subsidies to forestry industry
       Recreation: 2.6 million jobs $97.8 billion
       Logging: 76,000 jobs $3.5 billion
       Subsidies enforce bad practices, artificially lower prices

   Alternative materials: steel for framing, cork for
    flooring, kenaf for paper, other sources of fiber
    (sisel, jute, hemp, kenaf)
    Material Selection Intent
    Select materials with lowest possible
            environmental impact
   Renewable Resources
   Sustainable managed and harvested lumber
   Awareness of manufacturing impact on
    environment
   Durability and future recyclability
                                  Cost
     Market Drivers               Considerations


   Green materials introduction into
    marketplace   (Home Depot tax refund add)


   Increased advertisement and availability of
    green materials

   Rainforest destruction a continuing concern
    Key Solutions


   Select recycled content materials
   Use renewable resources
   Purchase local materials
   Advanced engineered products
Recycled Content - Plastic
Recycled Plastic Lumber
Reclaimed Lumber
Sustainably Harvested Lumber
Recycled and Low-Toxicity Paints
Rapidly Renewable Fibers
Natural Materials - Cork
Natural Materials - Fibers
Recycled Content - Glass
Recycled–Glass Aggregate
Rammed Earth
Steel Framing
Structure as Finish
Strawbale
Strawbale (2)
Summer House at KBG
Depot Kiosk
Autonomous House
         Materials Decision Matrix
   First Cost
   Availability (materials/labor)
   Performance (Code/function)
   Aesthetics
   Environmental attributes
   Local goods
   Life-cycle costs
     Performance-Based Analysis
 Structural strength
 Fire resistance
 Insect resistance
 Durability and expected life-time
 Necessary coatings and maintenance
 Labor and skill requirements
 assembly/installation
            Environmental-Based Analysis
 Life-cycle costs – ex. high R- value insulation - wear resistant materials -
   recycled, recyclable, salvage or disposal costs or benefits – high-quality and
   hand-crafted materials acquire value
 Environmental alternatives – based on building /Owner objectives
 Code acceptance - environmental alternatives can be problematic if not
   understood locally
 Availability - trade-offs from obtaining materials that are not locally
   available but have environmental attributes
 Producer’s qualification / criteria - Material Safety Data Sheet for
   certification of environmental qualities, especially third party certifications
   and test data
      Selection of Materials
Driven by:
•   Funding Agency / Owner
•   Existing Structures
•   Surrounding Neighborhoods
•   Cost
•   Architect
•   Climate
                                     Often
      Selection of Materials         Ignores

•   Operation expenses                Ignored
                                     because of
•   Maintenance costs
                                   Budget
                                   Breakdown
•   Longevity / Durability
                                   Time
•   Energy Efficiency              Unfamiliarity
•   Environmental Consideration    Perceived
                                   High Cost
•   Indoor environmental quality
      Selecting Green Materials
•   Ignoring these factors impedes change

•   Considering these factors provides an base for
    sustainable decision making

•   Open the design process to include the selection of
    Green materials
•   Educate the owners, designers, facility managers to
    the benefits of Greening

				
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