Should You Test for Radon When Buying a Home in Alabama?

Last updated: September 2026. Written by Byron Bennett, The Williams Group at Keller Williams Realty.

Radon is a colorless, odorless radioactive gas that forms when uranium breaks down in soil and rock. It seeps into houses through the foundation. The EPA estimates radon causes about 21,000 lung cancer deaths a year in the U.S. and calls it the number one cause of lung cancer among non-smokers. You cannot see it or smell it, and a standard home inspection does not measure it. That is why The Williams Group at Keller Williams Realty tells buyers in both of our markets to treat radon as its own line item, like the termite letter.

Is radon a problem in Alabama?

It depends on where you are, and even more on the individual house. ADPH names 15 counties with the highest radon potential in the state: Calhoun, Clay, Cleburne, Colbert, Coosa, Franklin, Jackson, Jefferson, Lauderdale, Lawrence, Limestone, Madison, Morgan, Shelby and Talladega. Most are in north and east Alabama, and ADPH notes that karst (limestone) areas, especially in north Alabama, show extremely variable readings. ADPH says radon levels “can vary greatly from home to home,” even next door, and recommends testing all homes.

For our two markets, that means Greater Birmingham buyers in Jefferson and Shelby counties are in a higher-potential area, and West Alabama buyers in Tuscaloosa County are in a lower-potential area. Lower potential is not zero. The only number that matters is the one from the house you are buying.

What do local radon test results look like by ZIP code?

ADPH keeps a public Radon Measurement Lookup that reports the number of homeowner tests returned since 2002 and their average for each ZIP code. We pulled the numbers for the areas we serve in September 2026. ADPH notes these are results from homes that chose to test, not scientific sampling, so treat them as a rough local picture, not a prediction for any one house.

Tuscaloosa, Northport and West Alabama

Greater Birmingham suburbs

Three things stand out. Every average is under the EPA’s 4 pCi/L action level. Several Birmingham-area averages (McCalla, Trussville, the U.S. 280 corridor, Mountain Brook and Vestavia Hills) sit in the 2 to 4 pCi/L range, where the EPA says to consider fixing. And an average of 2.57 across 191 homes very likely includes some homes above 4. West Alabama sample sizes are small, so a low Tuscaloosa average is not a reason to skip the test.

When should a buyer test for radon?

Order the test during your inspection or due diligence window in the purchase contract, at the same time as the home inspection. That timing leaves room to negotiate if the result comes back high. Many inspectors offer radon testing as an add-on; otherwise hire a certified radon measurement professional. ADPH points consumers to the National Radon Proficiency Program (NRPP) and National Radon Safety Board (NRSB) directories to find certified providers.

Waiting until after closing is the expensive way to learn the answer, because once you own the house the repair is yours.

How does a radon test work during a home sale?

The EPA’s Home Buyer’s and Seller’s Guide to Radon (revised March 2024) lays out two acceptable short-term options for real estate deals:

Either way, the home must be kept under closed-house conditions for at least 12 hours before and during the test: windows shut, doors used only for normal coming and going, and no fans that pull in outside air. The EPA says to fix the home if the result averages 4 pCi/L or more. Sellers should leave the device where the tester put it and keep the house closed until pickup.

What happens if the radon result is high?

High radon is a fixable problem, not automatically a reason to walk away from a house you love. The most common fix is sub-slab depressurization: a vent pipe and fan that pull radon from under the foundation and send it outside above the roofline. Your options usually look like this:

Get a written bid from a certified mitigator before you negotiate, so the number on the table is real. Your agent can help you frame the request so it keeps the deal together.

Does an Alabama seller have to tell me about radon?

Do not count on it. Alabama resale transactions generally follow caveat emptor (“buyer beware”), which puts the burden on the buyer to investigate. We explain the rules and the exceptions in our Alabama seller disclosure guide. The practical takeaway is simple: if you want to know the radon level, you order the test.

Sellers have a choice too. Testing before listing lets you fix a problem on your own schedule and hand buyers a clean report. If you already have a mitigation system, keep the installer paperwork and the post-mitigation test result ready for buyers.

What about new construction?

The EPA publishes a separate guide, Radon Protection: Buying a Newly Built Home. Ask your builder whether the home includes radon-resistant construction features, such as a vent pipe from under the slab that can be fitted with a fan later, and test after you move in either way. If you are shopping new builds, see our new construction buyer guide.

Can I get a free radon test kit in Alabama?

Sometimes. ADPH has offered one free radon test kit per Alabama household, most recently announced in January 2026, with the household paying only return shipping. Supplies run out: as of September 2026, ADPH’s testing page lists the free kits as currently unavailable and says the link will return when new kits arrive. Hardware-store and lab kits work for homeowners checking their own house, but for a purchase use the EPA sale protocol above.

Radon is only one line on a buyer’s checklist. On older or rural properties you may also want a septic and well inspection, and first-time buyers can start with our Complete Guide for first-time home buyers.

Local TWG perspective: how radon plays out in our markets

Radon rarely sinks a deal when buyers test early and put the fix in writing. The trouble comes when nobody tests, and the next buyer’s inspector finds it years later when you go to sell. In the Birmingham suburbs, and especially in homes with basements over the mountain and out U.S. 280, a radon test should be standard. In Tuscaloosa and Northport, where the county is lower-potential and many homes are built on slabs or crawl spaces, we still recommend it, because the cost of a test is small next to the cost of guessing.

Frequently asked questions

Whether you are buying over the mountain or north of the river, The Williams Group can point you to inspection and radon providers and help you negotiate a fair fix if a test comes back high.

Sources

EPA: Health Risk of Radon
EPA: Radon Resources for the Real Estate Community (Home Buyer’s and Seller’s Guide to Radon, 2024)
ADPH: Radon in Alabama
ADPH: Radon Testing
ADPH: Radon Measurement Lookup by ZIP code
ADPH news release: Free radon test kits (January 2026)