Ventilation for Energy Efficient Homes
How to protect your family from radon poisoning when you seal your home to make it energy efficient
Q: I'm told that sealing our house tight to save energy can make me and my family sick, and maybe even lead to cancer from radon. Is this true?
A: It's true that creating the tight building envelope required for energy efficiency can increase levels of indoor air pollution in your home, but most of these risks can be easily managed. Proper whole-house ventilation reduces the buildup of indoor air pollutants, and special systems called heat-recovery ventilators help contain energy losses as inside air is exchanged for fresh air from outside.
The issue of radon is more complex. Radon is a colorless and odorless radioactive gas that occurs naturally through the breakdown of uranium in soil. Under the right conditions, it can seep into basements, crawl spaces, or living areas, where it sometimes becomes concentrated. The U.S. Environmental Protection Agency has recognized radon as a carcinogen and established a protocol for testing and reducing levels within buildings.
For about $30 and up (including lab fees), you can buy do-it-yourself radon test kits online or at hardware stores and home centers. For $100 and up, you can hire a local radon-abatement contractor to perform a test for you. Virtually every home will have some radon, but a test reading of level 4 or higher (in pCi/L, or picoCuries per liter of air) indicates the need for correction.
Circumstances and solutions can vary, but typically the fix involves sealing any entry points in the foundation or slab, then installing a fan and duct to vent the gas up and out through the roof. According to the EPA, the costs for this can range from $800 to $2,500, with an average of about $1,200. Go to www.epa.gov/radon for information.