THE INSIDE SCOOP
GREEN BUILDER RECOMMENDS
Taking control of the air in your home is a key aspect of going green. To do so, you’ll first have to reduce some common sources of indoor pollution. That may mean removing or replacing certain carpets, cabinets, and getting rid of perfumes, scented cosmetics, and household cleaners. Next, test for leaks with a blower door, and use housewrap, insulation, and/or caulking to seal the gaps. Finally, install a central vacuum that removes particles from living areas, and an HRV or ERV that continuously replaces stale air without wasting excessive energy. Many building codes also require bath and kitchen ventilation.
An ERV transfers heat and moisture in hot climates. It dries incoming moist outdoor air and transfers some of that unwanted heat into the exhaust air stream that’s leaving the home.
ENERGY AND HEAT RECOVERY VENTILATORS KEY COMPONEN
You may have heard of energy recovery ventilator (ERVs) and their northern cousins, heat recovery ventilators (HRVs). This heat transfer technology is a key component of any modern “tight” house. Without them, modern houses would probably not be worth the foam, tape, and caulking they’re sealed with. These mechanical wonders take hot, unconditioned fresh air from outside, pass it over a heat collecting medium, where it gets a partial cooldown before entering the home. A recent study by John Bower www.healthyhouseinstitute. com found that using a heat recovery ventilator with continuous ventilation cost a Minnesota homeowner just $86 a year. It cost $188 to do the same ventilation without an HRV.
WHAT MAKES ONE CARPET GREENER THAN ANOTHER?
The EPA offers a few guidelines.
> Low or no volatile organic compounds (VOCs)
> No toxic dye
> Recycled content
> Reduced energy use (during manufacturing)
> Reduced or improved air emissions (during manufacturing)
> Minimum 10-year warranty
Recent EPA research found that carpet tiles can be a more sustainable alternative than wall-to-wall products. If you stain a section, for example, you can remove and replace it. Also, you can “rotate” tiles from heavy use areas to light use areas. The EPA’s test building used Milliken 36”x36” tile carpet and low-VOC adhesives to test these principles.
DUPONT TYVEK HOMEWRAP
Tyvek’s approach to housewrap is to focus on how the product contributes to overall HVAC performance by reducing air infiltration. The company says that by keeping insulation in the walls it protects future R-value performance. www.tyvek.com
MOHAWK SMARTSTRAND CARPET
One of the few large carpet companies to make major steps toward sustainability, Mohawk developed SmartStrand in a joint effort with DuPont to add renewably sourced polymers (from corn sugar and other sources) to a synthetic weave. The product has integral stain resistance, eliminating the need for toxic chemical treatments. www.mohawkflooring.com