Chapter 21 Flashcards
Enviromental Impacts on Buildings
- 30 to 40 percent of world’s energy use and associated greenhouse gasses
- One-third of U.S. energy use
- Two-thirds of U.S. electricity consumption
- 30 percent of U.S. raw materials consumption, 25 percent of its harvested wood, and 12 percent of its fresh water
- Nearly one-half of U.S. greenhouse gas emissions
Sustainable Building Construction
- Reduce the depletion of fossil fuels
- Minimize the use of valuable, productive land
- Minimize materials consumption and waste
- Protect forests and forest ecosystems
- Protect water resources
- Minimize air pollution
- Maximize the healthfulness of the interior building environment
The Building Life Cycle
Sustainable building construction must address all phases of the life of a building material, that is, from cradle to grave.
- Origin, manufacturing, and transportation
- Construction
- Use and maintenance
- Demolition, and reuse or disposal
USGBC
U.S. Green Building Council
LEED
Leadership in Energy and Enviromental Design
-Existing Buildings LEED-EB
-Commercial Interiors LEED-CI
-Building core and shell construction LEED-CS
-Homes LEED-H
also Schools, Retail, Healthcare, Neighborhood Development
LEED-NC
LEED for New Construction and Major Renovations projects LEED-NC
- Sustainable Sites
- Water Efficiency
- Energy & Atmosphere
- Materials & Resources
- Indoor Environmental Quality
- Innovation & Design Process
- Regional Priority Credits
LEED Classification
Platinum: 80+ points
Gold: 60-79 points
Silver: 50-59 points
Certified: 40-49 points
Other Green Building Assesment Programs
- Green Building Initiative Green Globes
- National Association of Home Builders (NAHB)Green Home Building Guidelines
- NAHB and International Code Council National Green Building Standard
Energy Conservation Programs
- American Society of Heating, Refrigeration and Air-Conditioning: Advanced Energy Design Guides
- U.S. Environmental Protection Agency: Energy Star
Product Certificaton
- green Seal
- Greenguard
- Scientific Certification Systems
- ISO 14000
Green Seal
- American Society of Heating, Refrigeration and Air-Conditioning: Advanced Energy Design Guides
- U.S. Environmental Protection Agency: Energy Star
Greenguard
Tests indoor products for acceptable Indoor Air Quality (IAQ) guidelines & standards
Scientific Certification Systems
Tests biodegradability and recycled content; also certifies forests under Forest Certification Program
ISO 14000
Collection of standards & guidelines covering performance, product standards, labeling, environmental management, and life-cycle assessment
Life cycle Assessment
- Definition of goals/scope of study
- Inventory analysis
- Impact assessment
- Improvement analysis or interpretation
Criteria for Evaluating Building Materials
- Embodied Energy
- Renewable Materials
- Recycled Content
- Energy Efficiency
- Use of Local Materials
- Durability
- Low Volatile Organic Compound (VOC) Content
- Low Toxicity
- Moisture Resistance
- Water Conservation
- Maintainability
- Potential for Recycling
- Potential for Reuse
Philosophy on Salvaged Material
- Salvaged materials should be used as much as possible.
- Doors & windows
- Cabinetry, furnishings, and equipment
- May be extra costs involved with preparation for reuse, but cost savings may occur relative to new construction
Metals
- Large amounts of embodied energy, but highly recyclable
- Steel with 30% recycled content, aluminum with 20% readily available
- Electroplating very toxic; use powdercoating or allow natural weathering when possible
Reclaimed Wood
Wood salvaged from old buildings and prepared for new use
Ecologically sound, unique visual character
Sustainable or Alternative Materials
- Engineered wood products – laminated ‘I’ joists, laminated veneer lumber
- Particleboard & formaldehyde-free MDF
- Straw particleboard – made from wheat straw, rice straw, & sugar cane
Certified Wood Products
- Products that use wood from sustainable forest management practices
- Forest Stewardship Council (FSC) best known in North America
Plastic
Plastics used in interior projects should be marked for recycling.
- Compostable plastics specified if possible
- PET from soft-drink containers used to make carpet
- Bioplastics, like PLA made from corn, used in carpet
- Newer plastics, like metallocene polyolefins can replace PVC
Adhesives
Adhesives are a major cause of VOC contamination – low VOC adhesives:
- Dry adhesives containing resins activated by pressure
- Water-based adhesives containing latex or PVA
- Natural plant resin/water based adhesives
Carpet
Carpet – three major considerations for sustainability
- Raw material use – PET & Wool
- Raw material disposal – recycling difficult; some carpet tile manufacturers have recycling programs
- Indoor air quality – fusion bonding, needlepunch process
- Carpet Research Institute Green Label
Vinyl Flooring
Durable, easy cleaning, low cost
High levels of PVC; look for low-PVC content
Rubber Flooring
- Made from recycled tires; durable, slip-resistant
- Can give off pollutants
Linoleum
- Made from natural, renewable products
- Does not generate static electricity
- Use low-VOC adhesives to maintain good IAQ
Cork Flooring
- Highly renewable
- Imported from S. Europe
- Excellent sound absorber
Wood Flooring
- Specify FSC-Certified wood
- Veneered/laminated products available
- Use prefinished material when possible to avoid IAQ issues
Bamboo and Palm Wood Flooring
- Renewable materials; bamboo matures in 3-5 years
- Palm wood is byproduct of coconut farming
Ceramic Tile
- High embodied energy due to production/transportation
- Natural materials, very durable, no emissions, low maintenance
- Avoid epoxy-modified grout, plastic adhesives, use low-VOC sealers
Gyp Wall Board
- 100% recycled paper covering
- 7% of gypsum is synthetic; major source is power plant emission reduction processes
- Disposal problematic; not easily recycled
Sisal Wallcovering
- Natural material
- Fairly rough, not suitable for wet areas
- Must use low-VOC adhesives; allow for expansion/contraction
Paints and Coatings
- Major source of VOC’s, IAQ problems in buildings
- EPA sets maximum VOC content, CA has stricter standards
- LEED credit for compliance with Green Seal Standard GS-11; only 20% of VOC standard allowable by EPA
Ceilings
- Can be made from recycled materials; content can be 95%
- Cheaper to recycle than sending to landfill in many cases
- Grid is recyclable
Furnishing
- Reused/refurbished furniture
- Select furniture made from highly recyclable materials (steel, solid wood, glass)
- Specify reclaimed/FSC-certified wood construction
- Specify formaldehyde-free MDF or strawboard
- Specify PET or natural fibers, organic cotton fabric for cushions, workstations
- Specify biodegradable/nontoxic dyes
- Specify low-VOC finishes
- Specify powdercoating or naturally-finished metals
- Require cushions to be foamed with CO2-injected foam
Building Commissioning
- Process of inspecting, testing, starting up, and adjusting of building sysems & verifying proper operation
- Necessary for LEED credit; cannot done by members of design team to receive LEED certification
Mechanical Systems
- Specify conformance with ASHRAE/IESNA Standard 90.1; required for LEED
- Specify mechanical system must not use CFC refrigerants; required for LEED
- Specify displacement ventilation (uses underfloor air supply/ceiling return) if possible
Electricty Use
- Reduce power use by ambient/task lighting, use daylighting strategies
- Specify automatic lighting/timers, submetering equipment when appropriate
- Specify daylight-responsive controls, energy-efficient appliances
- Specify high light reflectance finishes to improve daylighting
Plumbing
Specify low-flow fixtures & water use reduction strategies
IAQ
Indoor Air Quality
Two Types of Contaminents
- Chemical
- Biological
Chemical Contaminants
- Volatile Organic Compounds (VOC’s)
- Chemicals containing carbon, hydrogen, vaporize at room temperature
- Major sources of VOC’s are Paints, stains, adhesives, sealants, water repellants, particle board, furniture, upholstery, carpeting
- Formaldehyde – colorless gas with pungent odor; probable carcinogen found in resins & adhesives found in particleboard, wall paneling, MDF, furniture, carpet adhesives
- California Proposition 65 lists 76 chemicals that must be disclosed on products containing these compounds
- Greenguard Environmental Institute produces a list of products, chemicals, and maximum emission levels in order to be certified.
Biological Contaminents
- Mold, mildew, bacteria, viruses, mites, pollen, animal dander, dust, insects
- Mold & Mildew major causes of biological IAQ problems; only effective prevention is preventing/controlling moisture, limiting use of materials that provide nutrients
Causes of Poor Indoor Air Quality
- Chemical contaminants from indoor and outdoor sources
- Biological contaminants
- Poor ventilation
Symptoms of Poor Indoor Air Quality
- Sick Building Syndrome: symptoms disappear when occupants leave building
- Building-Related Illness: symptoms do not disappear after occupants leave bldg.
- Multiple Chemical Sensitivity: acute, long-term sensitivity to chemical exposure
Strategies for Maintaining Good Indoor Air Quality
- Eliminate/reduce pollution sources
- Control ventilation
- Establish good maintenance procedures
- Control occupant activity
Asbestos
- Naturally-occurring fibrous mineral
- Causes lung cancer, asbetosis, mesothelioma
- Exposure by friable (crumbled) or disturbed installation
- Must be tested/removed by certified, licensed contractors during demolition/renovation
Vermiculite
- Naturally-occurring mineral that resembles mica
- Expands by heating during processing; used as pour-in insulation, acoustic finishes, fire protection, sound-deadening compounds
- Some older installations may be contaminated with asbestos
Lead
- Highly toxic metal
- Used in paint prior to 1978, must be removed by certified, licensed contractor
- Most exterior uses phased out due to soil contamination; flashings, gutters, downspouts
Radon
- Colorless, odorless, tasteless radioactive gas
- Causes lung cancer; exposure by seepage through foundations
PCB’s
- Mixtures of synthetic organic chemicals
- Carcinogens; most uses banned under Toxic Substances Control Act of 1976
- Once used in building transformers, fluorescent light transformers, paints, coatings, plastic/rubber products
Adaptive Reuse
- Reusing as much of existing building stock as possible
- LEED credit for maintaining 75% of existing structure/shell, excluding windows & nonstructural roofing
- Additional credit for maintaining 50% of non-shell areas
- At smaller scale, components such as heavy timbers, doors, bricks, etc.; LEED credit for using 5% and 10% of total building materials
Recycled Materials
- Recyclability: previously used material’s capability for use as resource in manufacture of a new product
- Difficult in many cases due to need to separate substances, often by hand
Building Disposal
- If old products and materials cannot be reused or recycled, they must be burned or placed in landfills.
- Biodegradable materials break down quickly & return to earth
- Aluminum, plastics, and steel do not decompose quickly
- LEED credit for diverting 50% of construction, demolition, and land-clearing debris to recycling or donation to charitable organizations
- Biobased products can be used to minimize disposal problems; adhesives, composite panels, gypsum wallboard substitutes, ceiling tiles, carpet backing are available
- LEED credit for rapidly renewable materials (made from plants harvested on 10-yr. cycle or less) if they compose 5% of total building materials
