Here in Colorado, about half our homes have elevated levels of radon, a naturally occurring gas created by the decay of radioactive radium in our soils. It is the leading cause of lung cancer in non-smokers. Here’s a link for an excellent YouTube video explaining radon and how it’s mitigated.
Most real estate professionals, including the agents at Golden Real Estate, are well aware of this issue and will always advise the buyers we represent to have the home they are buying tested for the level of radon gas as part of the home inspection process.
Notice that I didn’t say to test for the presence of radon gas, but rather the level of radon gas. That’s because radon gas is present even in “fresh” air. But it can concentrate when it seeps into your basement, crawl space and even your above-grade living areas.
Since a high level of this gas is considered a “health and safety” issue, a seller is essentially obligated to accept responsibility for having the radon level mitigated or to compensate the buyer for doing it after closing.
At Golden Real Estate, we have a hand-held device smaller than a TV remote which we can lend to sellers prior to listing their home so they’ll know in advance what level of radon a buyer’s inspector is likely to discover. Ace Hardware has this same device for sale for $199.
There are less expensive mail-in radon tests that you can purchase at Home Depot or Lowe’s, but they’re also free at multiple locations — including from our office at 17695 S. Golden Road in Golden. These DIY kits should not be considered adequate for use in a real estate transaction.
During the home sale, it’s best to have a certified radon measurement contactor do the official test. You can find a list at www.ColoradoRadon.info. The test utilizes an electronic device which samples the air every hour over a 48-hour period. It can detect whether the device has been disturbed and whether there have been changes in atmospheric conditions which might suggest that windows or doors have been opened to allow fresh air into the house. Inspectors charge between $100 and $150 for this test, but it’s well worth the expense, especially if the results of the test show that the level of radon gas exceeds the EPA action level of of 4 picocuries per liter of air. If the test shows a level greater than that, the buyer can demand that the seller have radon mitigated. That typically costs about $1,000, so the testing is well worth the additional inspection cost.
Below is a diagram showing how radon is mitigated use sub-slab depressurization: