Home Buyer’s and Seller’s Guide to Radon
Check NACHI (https://www.nachi.org/radon.htm) for more information.
Radon has been found in homes all over the U.S.
- Radon is a cancer-causing, radioactive gas. You cannot see, smell or taste and has been found in homes all over the United States. It comes from the natural breakdown of uranium in soil, rock and water, and gets into the air you breathe. Radon typically moves up through the ground to the air above, and into your home through cracks and other holes in the foundation. Radon can also enter your home through well water. Your home can trap radon inside.
- Any home can have a radon problem, including new and old homes, well-sealed and drafty homes, and homes with or without basements. In fact, you and your family are most likely to get your greatest radiation exposure at home. That is where you spend most of your time.
- Nearly one out of every 15 homes in the United States is estimated to have an elevated radon level (4 pCi/L or more).
- Testing is the only way to know if you and your family are at risk from radon. The EPA and the Surgeon General recommend testing all homes below the third floor for radon.
- You cannot predict radon levels based on state, local, or neighborhood radon measurements. Do not rely on radon test results taken in other homes in the neighborhood to estimate the radon level in your home. Homes which are next to each other can have different radon levels. Testing is the only way to find out what your home’s radon level is.
U.S. Surgeon General’s Health Advisory
“Indoor radon gas is the second-leading cause of lung cancer in the United States, and breathing it over prolonged periods can present a significant health risk to families all over the country. It’s important to know that this threat is completely preventable. Radon can be detected with a simple test, and fixed through well-established venting techniques.”
If you are thinking of buying a home, you may decide to accept an earlier test result from the seller, or ask the seller for a new test to be conducted by a qualified radon tester. Before you accept the seller’s test, you should determine the results of previous testing by finding out:
- Who conducted the previous test (the homeowner, a radon professional, or some other person);
- Where in the home the previous test was taken, especially if you may plan to live in a lower level of the home. For example, the test may have been taken on the first floor. However, if you want to use the basement as living space, test there, too;
- What, if any, structural changes, alterations, or changes in the heating, ventilation, and air conditioning (HVAC) system have been made to the house since the test was done. Such changes may affect radon levels.
- If you accept the seller’s test, make sure that the test followed the Radon Testing Checklist.
- If you decide that a new test is needed, discuss it with the seller as soon as possible.
If the home has not yet been tested for radon…
- Make sure that a radon test is done as soon as possible.
- Make sure that the test is done in the lowest level of the home suitable for occupancy. This means the lowest level that you are going to use as living space which is finished or does not require renovations prior to use. A state or local radon official or qualified radon tester can help you make some of these decisions. If you decide to finish or renovate an unfinished area of the home in the future, a radon test should be taken before starting the project, and after the project is finished. Generally, it is less expensive to install a radon-reduction system before (or during) renovations rather than afterward.
If you are thinking of selling your home and you have already tested your home for radon, please provide your test results to the buyer.
No matter what kind of test you took, a potential buyer may ask for a new test, especially if:
- The last test is not recent, (e.g., within two years)
- You have renovated or altered your home since you tested
- The buyer plans to live in a lower level of the house than was tested, such as a basement suitable for occupancy but not currently lived in.
- A buyer may also ask for a new test if your state or local government requires disclosure of radon information to buyers.
If your home has not yet been tested for radon…
- Have a test taken as soon as possible. If you can, test your home before putting it on the market. You should test in the lowest level of the home which is suitable for occupancy. This means testing in the lowest level that you currently live in or a lower level not currently used, but which a buyer could use for living space without renovations.
- The radon test result is important information about your home’s radon level. Some states require radon measurement testers to follow a specific testing protocol. If you do the test yourself, you should carefully follow the testing protocol for your area or the EPA’s Radon Testing Checklist. If you hire a contractor to test your residence, protect yourself by hiring a qualified individual or company.
There are two general ways to test your home for radon. Because radon levels vary from day to day and from season to season, a short-term test is less likely than a long-term test to tell you your year-round average radon level. However, if you need results quickly, a short-term test may be used to decide whether to fix the home.
Long-term tests remain in your home for more than 90 days. Alpha-track and electret ion chamber detectors are commonly used for this type of testing. A long-term test will give you a reading that is more likely to tell you your home’s year-round average radon level than a short-term test. If time permits, long-term tests (more than 90 days) can be used to confirm initial short-term results. When long-term test results are 4 pCi/L or higher, the EPA recommends mitigating the home.
The quickest way to test is with short-term tests. Short-term tests usually remain in your home for a minimum of 48 hours. A longer period of testing is required for some devices. Usually, the testing device should be placed on an elevated surface in the middle of basement to get the most reliable result.
If you are testing in a real estate transaction and you need results quickly, any of the following three options for short-term tests are acceptable in determining whether the home should be fixed. Any real estate test for radon should include steps to prevent or detect interference with the testing device.
Using testing devices properly for reliable results.
- When you are taking a short-term test, close windows and doors and keep them closed, except for normal entry and exit. If you are taking a short-term test lasting less than four days, be sure to:
- Close your windows and outside doors at least 12 hours before beginning the test.
- Do not conduct short-term tests lasting less than four days during severe storms or periods of high winds.
- Follow the testing instructions and record the start time and date.
- Place the test device at least 20 inches above the floor in a location where it will not be disturbed and where it will be away from drafts, high heat, high humidity, and exterior walls.
- Leave the test kit in place for as long as the test instructions say.
- Once you have finished the test, record the stop time and date, re-seal the package, and return it immediately to the lab specified on the package for analysis.
- You should receive your test results within a few weeks. If you need results quickly, you should find out how long results will take and, if necessary, request expedited service.
During a radon test:
- Maintain closed-house conditions during the entire time of a short-term test, especially for tests shorter than one week.
- Operate the home’s heating and cooling systems normally during the test. For tests lasting less than one week, operate only air-conditioning units which re-circulate interior air.
- Do not disturb the test device at any time during the test.
- If a radon-reduction system is in place, make sure the system is working properly and will be in operation during the entire radon test.
After a radon test:
If an elevated level is found, fix the home. Contact a qualified radon-reduction contractor about lowering the radon level. The EPA recommends that you fix the home when the radon level is 4 pCi/L or more.
What should I do if the radon level is high?
High radon levels can be reduced. The EPA recommends that you take action to reduce your home’s indoor radon levels if your radon test result is 4 pCi/L or higher. It is better to correct a radon problem before placing your home on the market because then you will have more time to address a radon problem.
If elevated levels are found during the real estate transaction, the buyer and seller should discuss the timing and costs of the radon reduction. The cost of making repairs to reduce radon levels depends on how your home was built and other factors. Most homes can be fixed for about the same cost as other common home repairs, such as painting or having a new hot water heater installed. The average cost for a contractor to lower radon levels in a home can range from $800 to about $2,500.
How to Lower The Radon Level in Your Home
A variety of methods can be used to reduce radon in homes. Sealing cracks and other openings in the foundation is a basic part of most approaches to radon reduction. The EPA does not recommend the use of sealing alone to limit radon entry as it has not been shown to lower radon levels significantly or consistently.
In most cases, a system with a vent pipe and fan is used to reduce radon. These “sub-slab depressurization” systems do not require major changes to your home. Similar systems can also be installed in homes with crawlspaces. These systems prevent radon gas from entering the home from below the concrete floor and from outside the foundation. Radon mitigation contractors may use other methods that may also work in your home. The right system depends on the design of your home and other factors.