If you have not tested your home for the presence of cancer-causing radon gas in the past several years, do it this month.
Radon is the leading cause of lung cancer among non-smokers and the second highest cause of the disease among smokers. What’s more, effective January 2014, Minnesota homeowners will be legally required to disclose radon test findings to potential buyers. Fortunately, most radon problems can be corrected with a combination of basement sealing and ventilation.
According to the Minnesota Department of Health, about 80 percent of Minnesota counties are rated as high radon zones. Some 40 percent of the state’s homes built before 2010 are suspected of having unhealthy radon levels. With improved construction practices, the threat falls to 20 percent for homes built since 2010. But because concentrations can vary from house to house, the only way to know for sure that your home is safe is to test it.
Radon tests range from short-term do-it-yourself kits to long-term test to continuous monitoring devices. The longer the test, the more reliable the results. For an initial screening, choose a quick kit from any home center or hardware store or order one online. Place the open containers in your basement as directed for the prescribed time (usually three days) and mail them to the lab (About $40 for the test kit and analysis). A couple of weeks later watch for an email or letter with the test results. If the level is 4 pCi/L or higher, you’ll want to lower it to safeguard your family’s health and avoid future real estate problems.
How does radon enter the home?
The colorless, odorless radioactive radon gas naturally occurs in the ground and can enter homes several ways. As any gas, radon moves toward areas of lower pressure. It’s harmless when it rises to the surface and gets diluted in the air. But it can be deadly when it builds up in a home. The cumulative effects are greatest if the home has a basement bedroom or recreational spaces where family members spend many hours day after day.
Radon can enter a home through cracks in concrete slabs and poured foundations, uncapped hollow block foundations, pores and cracks in concrete block, floor-wall joints, mortar joints, unsealed sump pump covers and dirt crawl spaces. The risk is greater if the basement air pressure is lower because of inadequate fresh air for water heaters, furnaces and fireplaces or from the stack effect of warm air rising. Also, if the ground is frozen or saturated with surface water as it is in winter and spring, dangerous soil gases are even more likely to seep into basements because they can’t escape into the atmosphere.
After sealing blatant radon sources such as open sump pump pits, cracks and dirt crawl spaces, conduct a second test. If the radon level is still too high, a sub-slab depressurization system should be installed. It’s simply a PVC pipe with an energy-efficient in-line fan that draws radon gas from the sump and the perimeter drain tile under the slab and releases it into the air at the roof or out a wall with no windows nearby.
If you are planning to remodel your basement or replace your roof, contact Hoffman Weber so dangerous radon issues can be resolved before the projects begin. For more information on radon, read the Minnesota Department of Health’s radon brochure.