These days it’s common for a potential home buyer to request a radon test before the purchase. If the test result is at or above the maximum recommended level of radon – 4 picocuries per liter (pCi/L) or higher – mitigation is recommended. If you’re selling a home, get ready to spend between $1,000 and $1,500 for the mitigation. If you’re not selling your home but need radon mitigation anyway, you’ll spend between $1,000 and $1,500. Testing is done on the lowest lived-in level of the home.
I had our house in Warsaw tested for radon as soon as we decided to sell, knowing that most prospective buyers usually stipulate the test before purchase. A licensed tester came to the house, set up the radon sensing device, and returned in several days to pick it up. A day or so later, we were given the results. The radon level on the first floor of the house was above the safe level established by the feds. I figured that we might as well have the work done even before a potential buyer inspected the house because we’d probably have to do it anyway. I found myself wishing that I had checked the radon level when we built the home. But it seems that most people don’t bother with this until they are pushed to do so by a prospective buyer.
After mitigation was installed, the radon level was tested again and found to be 1.0 pCi/L, well below a dangerous level.
After moving into our present home, I found myself wondering about the radon level here. This house has a full basement and a sump pump. If radon is in the soil under the house, I felt sure that we would find radon in the air. Late last year, I ordered an Accustar radon test kit. The kits contain either one or two testing modules. I ordered one module at a cost of $25. Two modules are $50. I received a small testing device inside a plastic housing in the mail. The instructions explained how to set up the test and how long to test. There were no visible electronics and no electrical connections. I simply had to find a good place, put the device there, and leave it alone for at least 90 days. The instructions recommended that it be left in place for a full year. I didn’t want to wait that long, so I kept it in place for the minimum period of 90 days. At the end of the testing period, I wrote down the testing dates on a form and mailed the testing device back to the testing facility in a special envelope. Test results were returned to me in a week or so. Our radon level was reported to be at or higher than 4 pCi/L.
Not completely satisfied with the test results, I decided to spend another $125 and have a short-term test done by a local testing agency. This test involved the setting up of electronic equipment in our basement by a professional tester. The test equipment was mounted on a tripod and placed in a corner of a commonly used room. The test ran for several days and the equipment was picked up by the tester. Test results were provided to me a few days later, along with a letter and an invoice. The test report can be found here. The radon level was measured at 5.5 pCi/L, high enough to scare me into mitigation.
I called Three Rivers Environmental, a local radon mitigation company. A representative showed up a few days later and developed a preliminary plan for the mitigation process. Price: $1,000. I agreed to the price and scheduled the work.
A few days later, two men showed up at a prearranged time. They explained exactly what they had to do to make sure we removed most of the radon from the air in the house. The basic idea behind mitigation begins with a recognition that radon exists underground naturally and, through various means, can find its way into homes. In my case, our basement was constructed with a drainage system of tile that follows the perimeter of the basement. The drain tile is beneath the floor of the basement. The tiles are constructed to carry water into a sump pit, where excess water is removed via a sump pump. Radon gas collects under the basement and finds its way into the house through the drain tiles and the sump pit.
I took photos after the project was complete (see below).
The first photo was taken in the basement. A hole was drilled in the floor of our utility room above the drain tile. After the hole was drilled, dirt was removed from beneath the floor to make an open area or pocket. A vertical 4 inch PVC pipe was inserted into the hole, with its end projecting slightly into the open air pocket. A sealant was placed on the floor around the base of the pipe. A 90 degree bend was installed at the top of the pipe and a short section of straight pipe was installed to extend the pipe into the garage.
In the garage, a bend was placed on the stub pipe extended from the basement. A vertical pipe was attached to the bend and extended through the ceiling.
An air flow indicator was installed on the pipe in the garage. If the red liquid is at the “zero” level on both sides, there is a problem and the installer must be notified. A problem could arise if the water level below the basement rises high enough to cause water to be sucked into the mitigation piping. You do not want this to happen.
In the attic, an exhaust fan was installed on the PVC pipe. An existing electrical circuit was tapped into and an outlet placed near the fan. The PVC was extended through the roof above the fan.
Finally, a cover was installed over the top of the sump pit in the basement. The cover was caulked around its edge with silicone. The fan was plugged into the outlet in the attic and the air flow started.
Test equipment was left in the basement by the installation crew.
A technician came to remove the equipment several days later. He read the test results before leaving, and the radon level was measured at 1.1 pCi/L. The mitigation procedure was a success.
Now we can breathe a bit easier.