Improving indoor air quality continues to be a priority in green homebuilding.
Americans spend as much as 90 percent of their time indoors, yet the air in homes can be 10 times more polluted than outdoor air, according to the U.S. Environmental Protection Agency.
A common source of indoor air pollution is the off-gassing of chemicals or volatile organic compounds (VOC) found in many building materials. Off-gassing is the evaporation of volatile chemicals in non-metallic materials at normal atmospheric pressure. This means building materials can release chemicals into the air through evaporation. This evaporation can continue for years after the products are initially installed, which means you continue to breathe these chemicals in your home.
Children are particularly vulnerable when it comes to air pollution. A report in the New England Journal of Medicine states that 40 percent of children will develop respiratory disease, in part because of the chemicals in their homes. Common health problems include eye, nose and throat irritation and the worsening of asthma symptoms. Headaches, dizziness, nausea and vomiting are also common side effects from exposure to off-gassing of VOCs.
The Triad Green Building Council and its members are dedicated to building homes with materials that have low or no volatile organic compounds. Although many people like that “new house smell,” it’s a likely indication that there are harmful chemicals in the indoor environment. Many building products we have in our homes release, or “off-gas,” VOCs. Some examples of sources of these compounds are:• Carpet, vinyl flooring and adhesives. • Cabinetry and countertops.• Paints, varnishes, stains and floor finishes.• Caulks and adhesives.• Plywood and particleboard.• Insulation.
Don’t be fooled into thinking that only building materials off-gas VOCs. Many homes have elevated levels of VOCs that are brought into the home. Possible outside sources of VOCs include:• Ready-to-assemble furniture or shelving.• Air fresheners or air cleaners.• Dry-cleaned clothing,• Cleaning and disinfecting chemicals.• Gasoline or petroleum products.• Lawn chemicals and pesticides.• Vehicle emissions in garages.
Fortunately, the building products industry is responding to these indoor pollution problems by developing safer products, including low-VOC paints and adhesives and formaldehyde-free insulation, plywood and flooring products. The best health protection measure is to limit your exposure to products and materials that contain VOCs when possible.
If you think you may be having health problems caused by VOCs, try reducing levels in your home. Increasing ventilation and limiting potential sources of VOCs is the most effective strategy. Increase ventilation by opening doors and windows, use fans and maximize air brought in from outside. Additionally, keep both the temperature and relative humidity as low as possible or comfortable. Chemicals will off-gas more under warmer conditions with high humidity. Conduct an inspection of your home for the common sources of VOCs. Once you determine the probable sources of VOCs, steps can be taken to reduce your exposure. If you are unable to determine probable sources, a professional indoor air quality investigator can be consulted.
Ultimately, the most effective way to limit VOCs indoors is to limit the potential sources of VOCs. Take time to read and understand product labels, seek out products that contain low or no volatile organic compounds, and increase the amount of outdoor “fresh air” into a home to dilute and reduce the levels of these compounds.
Scott Allred is chairman of the Triad Green Building Council and the owner of Precept Construction. He can be reached at scott@preceptconstruction.com or 286-6811. For additional resources on green building, visit www.triadgreenbuilding.org or www.preceptconstruction.com.
