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“Lively Somerville” Promoting Green Building and Renovation. Green Building elements and Somerville’s focus on toxic materials. What is toxics use reduction? Why are the hazardous substances in building materials a concern? What are the alternatives? What can you do?.
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“Lively Somerville” Promoting Green Building and Renovation • Green Building elements and Somerville’s focus on toxic materials. • What is toxics use reduction? • Why are the hazardous substances in building materials a concern? • What are the alternatives? • What can you do?
Building Materials with Hazardous Components • Wood Products • Pressure Treated Wood • Composite Wood Products • Flooring • Insulation • Concrete • Paints and Finishes • Caulk and Adhesives
Product impacts through lifecycle Storage and transport Use Use Extraction and Production Disposal
Building Impacts USGBC estimates U.S. commercial and residential building create or consume: • 65.2% of total energy consumption • 30% of total greenhouse gas emissions • 136 million tons of construction and demolition waste (approx, 2.8 lbs/person/day) • 12% of potable water • 40% (3 billion tons annually) of raw materials us globally
When are the hazardous building materials a human health concern? • Production • Use • Installation • Occupant Use • Maintenance • Disposal Workers Exposure Occupant Exposure Workers and Occupant Exposure
Why Are Building Materialsa Concern for the Builder? • Some very common building products are known to cause: • reproductive disorders • cancer • nervous system disorders • asthma and allergies • Builders receive both short-term and long-term exposures to these chemical hazards: • Off-gassing VOCs - solvent based products and cleaners • Particulates - saw-dust and dusts from construction materials.
Outdoors 10% Indoors 90% Why Are Hazardous Building Materials a Concern for the Homeowner? The average person spends more than 90% of their time indoors. Air in new homes can be 10 times more polluted than outdoor air. (EPA)
Why Are Hazardous Building Materials a Concern for the Homeowner? • Over 500 pollutants have been identified in building materials. • Focus on tighter house construction for energy efficiency, means less ventilation of harmful vapors. • Exposure to chemicals in the indoor environment can cause short and long term health problems: • Short term - Lung irritation • Long-term – Asthma and allergies.
Why are children more affected by hazardous products than adults? Children breathe more air in proportion to their body weight than do adults. Thus, they breathe in more of the chemicals. Children’s immune systems are not fully developed. They can not detoxify the hazardous materials as well as adults. Children also play close to the ground and have more hand-to mouth activity.
Toxics in Building Products • Formaldehyde • probable human carcinogen when inhaled or ingested • Volatile Organic Compounds (VOCs) • Petroleum –base solvents
What is Formaldehyde? • It is a major ingredient used in industrial products as an adhesive, antiseptic*, germicide*, fungicide* and preservative. • It is a strong-smelling, colorless gas that ischemically unstable. • It will off-gas for a long time.
What is off-gasing? • When solid materials evaporate at room temperature. • Chemically unstable materials slowly release contaminants, including some additives such as dyes, solvents, and softeners. • Time – some emissions decrease slowly over a long-period, while others cure immediately. • Humidity can slow down the curing process and increase length of time material off-gases. • VOCs are absorbed by some materials and re-released into the air. Materials that absorb VOCs include; plaster, rugs, and fabric.
Formaldehyde:Off-Gassing • Formaldehyde is combined in the factory with other chemicals (urea or phenol) to form resins. • When formaldehyde products are exposed to increased temperature and humidity, they start a chemical reaction which breaks apart the resin, and releases the formaldehyde. • Urea formaldehyde is more reactive to moisture and off-gasses more than phenol formaldehyde.
Formaldehyde: Products • MILDEW • WATERPROOFING • ANTI-STATIC AGENTS • PRESERVATIVES • ACRYLIC MATERIALS • WOOL FIBERS • NYLON FIBERS • RAYON • CARPET BACKING • FIBERBOARD • GLUES • FLAKE AND WAFER BOARD • PARTICLEBOARD • PLYWOOD PANELING • INTERIOR & EXTERIOR GRADE PLYWOOD • FIBERGLASS & MINERAL WOOL INSULATION • BINDERS • FORMICA • PLUMBING FIXTURES • COUNTER & TABLE TOPS • RESINS & OIL-BASED PAINTS • PAINT & WOOD FINISHES
Formaldehyde:Off-Gassing Does the Formaldehyde ever go away? • The off-gassing process can continue as long as the material is exposed to sufficient moisture levels. • Gradually, the "off-gassing" declines, but never goes to zero. • It always returns when it is exposed to elevated temperature and humidity.
Formaldehyde: Exposure Rates • Indoor air commonly measures 0.03 - 2.5 PPM (higher rates exist where off-gassing occurs) • Most people will first react to formaldehyde when the levels are in the range of 0.1 to 1.1 parts per million.
Formaldehyde: Health AffectsExposure Levels • No effects 0 - 0.05 PPM • Odor threshold 0.05 - 1.0 PPM • Neurophysiological effects 0.05 - 1.05 PPM • Eye irritation 0.05 - 2.0 PPM • Upper respiratory irritation 0.10 - 25 PPM • Lower airway and pulmonary effects 5.0 - 30 PPM • Pulmonary edema, pneumonia 50 - 100 PPM • Death 100 PPM
Product Formaldehyde Emissions (µg/m²/hr) Fiber Glass Insulation (R-19) 32 Permanent press shirt (unwashed) 107 Permanent press shirts (washed once) 45 Permanent press draperies 215 ½” Hardwood plywood 103 ¾” Industrial Particleboard 170 ¼” Prefinished plywood wall paneling 181 20 mil Cabinet decorative laminate 51 Floor finish (base coat, after 22 hours) 10,800 Formaldehyde: Product Emission Rates
Off-Gassing: Volatile Organic Compounds (VOC) • Definition of VOCs • Organic solvents that form vapors at room temperatures and easily evaporate into the air. • VOCs can be toxic, harmful to the environment, flammable. • Sources of VOCs • Oil Based Paints • Plastics • Adhesives and Glues • Solvents • Carpet backing • Asphalt compounds • Plastic foams • Vinyl flooring
Health Impacts of SolventsReproductive and Developmental Toxicity • Reproductive: • Infertility • Early miscarriage • Sperm toxicity • Developmental: Toluene - “Fetal Solvent Syndrome” • Birth defects • Growth and developmental delays, IQ deficits, hyperactivity, attention deficits
Health Impacts of SolventsNervous System • Peripheral Nervous System (arms, legs) • Motor: weakness, uncoordinated, fatigue, tremor • Sensory: numbness, tingling, visual or hearing problems • Central Nervous System (brain) • Thought Processes: memory loss, confusion • Emotional State: nervousness, irritableness, depression, apathy, mood swings
Overview: Green Building Goals People • Minimize exposure to workers • Create healthy spaces for occupants • Use low maintenance, durable materials Environment • Use resources, water and energy efficiently • Avoid limited, nonrenewable resources • Minimize environmental impacts
Design and Construction Opportunities to Create Healthy Homes • Building materials are only one aspect of healthy building • Landscaping • Foundation • Radon control • Building envelope • Air tight construction • Ventilation and filtration • Heating and air conditioning • Moisture control
What is Toxics Use Reduction (TUR)? TUR examines the use of chemicals in a system, process or product, and asks: • Why is this chemical being used? • Is there another method or product that does not require the use of a hazardous chemical? • If the activity truly requires chemical use, is there a safer chemical alternative? • If no alternatives exist, is the chemical being used safely and efficiently?
Building Materials with Hazardous Components • Wood Products • Composite Wood Products • Pressure Treated Wood • Flooring • Insulation • Concrete • Paints and Finishes • Caulk and Adhesives
Composite Wood Products:Plywood Conventional plywood is made of thin veneers of wood, bonded together with formaldehyde resins. • Hardwood Plywood – interior grade • Is used indoors for cabinetry and paneling • Uses urea-formaldehyde (UF) glue as an adhesive to bind a core layer to a facing of higher quality woods. • Softwood Plywood - exterior grade • Is used for exterior and interior structural applications - walls, roofs, subfloors (resilient, wood and laminate flooring and ceramic tile) • Uses phenol formaldehyde resin as an adhesive, which is a water-resistant glue. It off-gasses at a slower rate than urea formaldehyde glues.
Composite Wood Products: Particleboard • Is used for substrates in counter tops, shelving, stair treads,cabinets, door cores and manufactured home decking. • It is used for subflooring under carpet, and laminate and resilient flooring. • It is not as structurally sound as plywood and is vulnerable to moisture. Particleboard is smooth, knot-free, and hard. It has great impact resistance. • Is made from wood chips bonded with urea formaldehyde resins under heat and pressure.
Composite Wood Products:Medium Density Fiberboard (MDF) • Is used indoors for underlayment of countertops, cabinet walls and shelves, millwork, molding, door parts, paneling, and laminate flooring. • It is often painted, laminated or sealed. • Is made from wood chips and sawdust bonded with urea formaldehyde resins under heat and pressure. • EPA notes that Medium density fiberboard contains a higher resin-to-wood ratio than any other UF pressed wood product and is generally recognized as being the highest formaldehyde-emitting pressed wood product.
Composite Wood Products:Oriented Strand Board (OSB) • Is used for sheathing. • Is made from wood chips bonded with phenol formaldehyde resins. • OSB was introduced as an attempt to compete with plywood as a structural material while using a low quality resource.* • OSB is three times as strong as particle boards of the same density and resin content.
Alternatives to Formaldehyde Wood Composite: Bio-BasedWood Composites forSub-Flooring • Bio-based building materials are produced from plant fibers including: agricultural and forestry by-products such as soy, wheat, corn, kenaf, jute, sunflower seeds, hemp, bamboo, wood and paper waste. • They can be used for for interior walls, ceilings, flooring, movable partitions, cabinets, furniture, shelving, etc.
Alternatives to Formaldehyde Wood Composite: Bio-BasedWood Composites forSub-Flooring • They are ground up or heat/moisture treated, mixed with PMDI – a non-formaldehyde binder, and molded into building products. • Although they are comparable in price to plywood, they are not available locally and transportation costs are not economical. • They PMDI is made from benzene and contains diisocyanate which is a known occupational asthmagen. We have not found any studies that data confirming that confirm that MDI does not off-gas after it has cured. Green industry people feel that it is less hazardous than formaldehyde.
Hierarchy of Alternatives: NontoxicSubflooring Formaldehyde Free Plywood or Particleboard with PMDI binder • It is not cost effective when shipping is included for affordable housing. Fiber/Cementboard • This is a thin, high-density underlayment used in situations where floor height and moisture is a concern. • It can be used with carpeting, laminate flooring, resilient flooring and ceramic tile. Cementboard • Cementboard is used with ceramic tile installations. • It is completely stable, even when wet, as it has a concrete core and is faced with fiberglass. • Cementboard is more expensive than a plywood installation.
http://www.greenguide.com Formaldehyde- free laminated sheathing formaldehyde free particleboard made from recycled money formaldehyde-free sustainable yield veneer panels
Hierarchy of Alternatives: Less ToxicSubflooring Exterior Grade Plywood with Phenol Formaldehyde • Has a water-resistant glue • Air well • Off-gasses at a slower rate than urea formaldehyde • Seal with sealer product
Cabinets and Countertops: Problems Uses Urea Formaldehyde wood products: • Interior grade plywood with Formica • Melamine or Formica with particleboard core Extent of Exposure • On average, 15 sheets of wood products are used to build cabinets.* • Gases can build-up in cabinet and be released when opened.
Cabinets: Hierarchy ofAlternatives Alternative Cabinets in order of preference - • Solid Wood, Metal, or Glass • Veneers with plywood or MDF substrates with phenol formaldehyde or PMDI (both hard to find) Alternative Cabinet Materials • Factory applied finishes • Water-based glues
Cabinets: Hierarchy ofAlternatives • Sealed Masonite has fewer volatile organic chemicals than particle board • Look for low-emission plywood and particleboard products with the following seals; • European E1 (higher standard than U.S. HUD) • U.S. HUD Label There is no HUD label for MDF board.
Pressure Treated Woods: Issues • Hazardous Types • CCA – Chromated Copper Arsenate • ACA – Ammoniacal Copper Arsenate • Hazards - contain heavy metals including arsenic salts and chromium compounds which can leach out of wood on-site: • Toxic to humans and can affect target organs (liver, kidneys, etc.). • Toxic to the environment and can build up in the soil. • By Jan. 2004, EPA will not allow CCA products for any of these residential uses: • Play-structures, decks, picnic tables, etc. • Landscaping timbers, residential fencing, patios and walkways/boardwalks.
Pressure Treated Woods: Alternatives • Recycled plastic or plastic composite lumber (structural issues)** • 100% recycled plastic • Wood fiber and recycled HDPE plastic • Fiberglass reinforced HDPE plastic • FSC-Certified untreated, naturally rot-resistant, heartwood – caution, these can be naturally toxic (check local codes)** • Cypress, Elm, Western Cedar, IPE and Black Locust • Redwood and teak are mentioned but have other environmental issues • Where sill plate is 18” above grade, a metal termite shield can be used instead of a treated sill plate, (check local codes).*
Pressure Treated Woods: Alternatives ACQ – Alkaline Copper Quat Although, ACQ is considered less toxic than CCA and ACA, it is not nontoxic. • It can be used in any application that requires pressure treated lumber. • Quaternary compounds are an asthmagen. • The copper may be toxic to insects and aquatic life.*
Pressure Treated Woods: Alternatives • Boron based woods – limited to aboveground, covered use • Any wood - engineered, sheathing, dimensional - can be treated by this method. • Eliminates need for termite treatments and maintenance calls. • Penetrates heartwood (CCA does not). • Non-toxic for handling, cutting, and disposal. • Does not need to be site-treated on cut ends (CCA does). • Borate pressure-treated material adds about $2,500 to the costs of an average sized frame house. • Metal – steel coated with baked enamel
Cement: Additives & Alternatives These products are mostly an issue for people who have chemical sensitivities
Siding Alternative: Fiber Cement Siding • Fiber-cement composites offer an extremely durable, attractive and fire-proof alternative to wood. • Can be textured to exhibit a wood-grain appearance or smooth in a stucco-type finish. • Is available in panel, plank and shake styles. • Some fiber-cement siding requires painting before use and some comes primed. • Cutting the siding produces a great deal of dust. Shears, rather than saws, are best used to cut the material.
Materials Selection: Setting Priorities • Short and long term exposures for workers and homeowners. • Quantity – how much of the material will be exposed in the house? • Carpet and floor tile large areas • Location – how close is a the material to the occupant or air handling systems? • Duct materials are in contact with the ventilation system • Vinyl tile maybe out in the unventilated mudroom • Maintenance Requirements – what products are necessary to maintain a material? • Insecticides to prevent insect infestations in wool rugs • Biocides to stop mold in carpets • Solvent based finishes on vinyl tile floors
Materials Selection: Setting Priorities • Emissions and Durability – what gases and particulates will be emitted during installation and use? • Fiberglass particulates are released during installation and use if not properly encapsulated. • Soft plastics, carpets, and formaldehyde in products will break down. • Plastics and solvent based-finishes emit VOCs. • Metals, glass, ceramics and some woods do not off-gas and break-down over time. • Duration of off-gassing – how long will the material off-gas? • Paint finishes cure in a short time under the proper conditions. • Formaldehyde products and plastics off-gas for long periods of time.
Summary of Alternative Products • Minimize use of formaldehyde based wood composite products. Use phenol formaldehyde or PMDI instead of urea formaldehyde as the binder. • Avoid products with Polyvinyl chloride (PVC). • Use water-based finishes and adhesives. • Eliminate wall to wall carpet, or use low or non-emission carpet and carpet components.
Off-Gassing - Sealing in the Gasses What is a sealer? It is a type of coating that is typically used to coat a porous surface to prevent stains and water damage. How can a sealer affect the formaldehyde? Sealers and finishes trap the formaldehyde gasses, slowing or preventing the product off-gassing.