One of the inspections home buyers usually schedule in central Ohio is a test for radon. Radon is a naturally occurring radioactive gas produced by the breakdown of uranium in soil, rock and water. The test is done during the inspection phase of the Purchase Contract. The test will cost the buyer between $110 to $150, depending upon the company the buyer hires to do the test.
The inspector will place a small testing device (silver box in photo) in the basement for a 48-hour period. The device will periodically sample the air. At the end of the test, it will produce a graph of the readings, then average them for each of the two 24-hours periods. The overall average is then used to determine whether mitigation is recommended. The EPA suggests that people not have long-term exposure to radon readings at or above 4.0pCi/L. (non-scientific people shorten this to “4 pico curies”.)
If the reading suggests mitigation, then a company is hired that does such work. Costs vary according to the layout and size of the basement and the subsequent amount of materials required. The least expensive that I’ve seen a mitigation cost is around $1000.
In doing the mitigation, the company will seal the sump pump with a special cover, cover any crawl space with heavy plastic and perhaps, caulk cracks in the concrete floor. As shown in this photo, a plastic pipe will run from the pump to an exterior wall, then be extended to the exterior.
On the outside a fan will be installed that will be sucking out the air from the spaces that are likely to be contributing to radon entering the home. This is primarily the sump pump but a pipe may also be installed under the plastic in the crawl space.
The outside fan and piping is usually installed in a somewhat hidden location if possible. Sometimes there are options on placement of this equipment, so you want to discuss with the mitigation company what the location options are. Keep in mind that this fan runs all the time. While it’s not much louder than the fan on your furnace, you may not want to listen to it if it’s near your deck.
I’ve not included any of the scientific information on radon in this post. You can read to your heart’s content on this EPA page where there are many detailed articles. You can also view a U.S. map or an Ohio map (scroll down the page to see Ohio map) of radon concentrations.