Is radon a problem in Utah homes?
Yes, radon is a common problem in Utah homes. The Utah Department of Environmental Quality says about one in three tested homes is above the EPA's 4 pCi/L action level, and the only way to know about a specific house is to test it. In a purchase, that means a short-term test during due diligence and, if it comes back high, a mitigation system.
Yes, radon is a real problem in Utah homes. The Utah Department of Environmental Quality says about one in three Utah homes has elevated radon (Utah DEQ Radon Program, checked October 2026).
That figure comes from homes that were tested, not a random sample, and it does not tell you anything about one particular house. Two houses on the same street can test very differently. The practical answer is the same everywhere in the state: test the house you are buying, and fix it if the number is high. Both steps are routine.
What radon is, and why the state cares
Radon is a radioactive gas that comes from uranium in soil and rock. It has no color, smell or taste, and it moves up through the ground into buildings, collecting in the lowest levels.
The neighborhoods where the housing age makes this most worth testing: Quail Hollow and Bell Canyon in Sandy, Oquirrh Shadows in West Jordan and White City on the east side.
The health case comes from federal and state agencies, not from the testing industry. The EPA says radon is the second leading cause of lung cancer overall and the leading cause among people who have never smoked, and estimates it is responsible for about 21,000 lung cancer deaths a year in the United States (EPA, Health Risk of Radon, checked October 2026). The Utah Geological Survey has written that the vast majority of geologic hazard deaths in Utah to date have come from radon exposure (Utah Geological Survey, Survey Notes, September 2016).
The number that matters: 4 pCi/L
Radon is measured in picocuries per liter of air, written pCi/L. The EPA’s action level is 4 pCi/L: at or above it, the EPA recommends fixing the home, and it suggests considering a fix between 2 and 4 (EPA, checked October 2026).
The Utah DEQ uses the same line. Its guidance is to consider mitigation above 4 pCi/L, consider a long-term test between 4 and 6 if you want a year-round picture, and retest every two to five years if the result is below 4 (Utah DEQ Radon Program, checked October 2026).
| Result | What Utah DEQ and EPA guidance suggests |
|---|---|
| Below 2 pCi/L | No fix needed; DEQ suggests retesting every two to five years |
| 2 to 4 pCi/L | EPA suggests considering a fix |
| 4 pCi/L or higher | Mitigate the home |
| After mitigation | Retest, no sooner than 24 hours after the system starts running |
Is there a radon map for Utah?
Yes, two kinds, and they answer different questions.
The DEQ ZIP code search. The Utah DEQ Radon Program offers a ZIP code search at radon.utah.gov showing median test results by area. This is measured data from homes that tested.
The Utah Geological Survey hazard potential maps. The UGS has mapped indoor radon hazard potential based on geology, including a 1996 map of the western Salt Lake Valley and a 2014 hazard map set covering parts of Herriman, West Jordan and South Jordan. These show where the ground favors radon, not what any house measured.
Both are useful for understanding an area. Neither replaces a test. The state’s own data notes that housing structure, age and condition are major drivers of radon levels, which is why neighboring homes can differ (Utah Environmental Public Health Tracking, radon data notes, checked October 2026). A low-risk ZIP code does not clear a house, and a high-risk one does not condemn it.
How radon testing works in a Utah home purchase
Radon testing is not required in a Utah home sale. A past president of the Utah Association of Realtors told KSL in January 2026 that it is not mandatory (KSL, January 20, 2026). It is still one of the most common add-ons to an inspection, and it has to happen inside the due diligence period so that you can act on the result. What due diligence means in a Utah contract covers how that deadline works.
The Utah DEQ’s real estate guidance sets out how a transaction test should be done (Utah DEQ, Radon and Real Estate Transactions in Utah, checked October 2026):
- Where: the lowest level of the home suitable for occupancy, chosen with the buyer’s future use in mind. Not a crawl space, and not a bathroom or kitchen.
- How high: at least 20 inches above the floor, where it will not be disturbed.
- How long: a minimum of 48 hours.
- Conditions: closed-house conditions for at least 12 hours before and during the test, meaning windows and outside doors kept shut.
- Who: preferably an independent tester listed with the National Environmental Health Association’s radon proficiency program, with their ID number on the report.
The EPA’s buyer and seller guidance describes three acceptable short-term approaches for a sale: two passive tests side by side, two passive tests back to back, or one continuous electronic monitor, each for at least 48 hours, and says any real estate test should include steps to prevent or detect tampering (EPA, Home Buyer’s and Seller’s Guide to Radon). A continuous monitor has one practical advantage in a transaction: it records hour by hour, so a tester can see whether the readings were steady or disturbed.
If the house has an unfinished basement you plan to finish, test that level. Buying a house with an unfinished basement explains why to test again after you finish it, since finishing changes how air moves.
What the seller has to tell you
The Utah seller’s property condition disclosure asks about hazardous conditions, including radon gas in the house or well, and the seller answers yes, no or do not know (Utah DEQ, checked October 2026). A “no” usually means the seller never tested, not that the house is clean. If the seller has a past result, ask for the full report, check where and when it was done, and test again if the house has been remodeled since.
What mitigation involves
If the test comes back at 4 pCi/L or higher, the fix is well established. The Utah DEQ calls active soil depressurization the most effective and cost-efficient method: holes are cut through the slab, and a pipe connects to a fan that creates a vacuum beneath the house, pulling radon from under the slab and venting it outside. The DEQ notes the fans use about 60 watts (Utah DEQ, checked October 2026).
On cost, the DEQ’s real estate page says mitigation systems in Utah average $1,800, depending mainly on the type of foundation and the size of the home (Utah DEQ, checked October 2026). Treat that as a guide, not a quote, and get a written bid from a nationally certified mitigator. The DEQ links to the NRPP and NRSB directories of certified professionals.
In a transaction, the parties decide who pays and when. The DEQ notes that escrow arrangements or contingencies tied to an acceptable radon result can be used. In practice it usually becomes part of the inspection response, alongside everything else on the report. Do I have to fix everything on the inspection report in Utah covers how sellers tend to respond.
New construction is not automatically radon resistant
This surprises a lot of buyers. The Utah DEQ states that there are currently no statewide regulations in Utah requiring radon resistant construction; the state encourages builders to use it voluntarily (Utah DEQ, checked October 2026).
Some builders install a passive system anyway: gravel or perforated pipe under plastic sheeting beneath the slab, with a vent pipe routed up through a warm part of the house so it draws without a fan. The DEQ’s guidance notes that if a builder plans for it, a fan can be added later if a test shows the passive system is not enough. On a new build, ask the builder directly whether a passive system is included, and test after you move in either way. A brand-new house can test high.
What I tell clients
I tell clients to add radon to the inspection on any Utah house with a basement, and on most without one. In my experience the test is the easy part. The mistake is skipping it because the seller says they have never had a problem, or because the house is new.
What happens during a home inspection in Utah covers the general inspection, and radon sits alongside it as a separate test. I am Kelsey Earl, a Realtor with Keller Williams South Valley, and if you want help lining up testing inside your deadline, get in touch.
Note: This is general information drawn from EPA and Utah DEQ guidance, not medical, legal or engineering advice. For health questions, talk to a doctor. For a specific house, rely on a certified radon professional and your actual purchase contract.
Let's talk it through.
Call or text me at 801-419-8917, or email [email protected]. I look forward to chatting with you.
Get in touch Kelsey Earl, Realtor®
Keller Williams South Valley
801-419-8917
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[email protected]