Radon Testing in Metro Detroit
Continuous-monitor radon testing with written results. About 1 in 4 Michigan homes test above the EPA action level — the only way to know yours is to test.
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Home › Radon Testing
What It Is
What radon testing covers.
Radon is a colorless, odorless radioactive gas that seeps up from the soil into homes. It's the second-leading cause of lung cancer in the United States and the leading cause among non-smokers — and you cannot see, smell, or taste it. The only way to know a home's level is to test.
How much radon to expect depends on where the house sits. Statewide, the Michigan Department of Environment, Great Lakes, and Energy (EGLE) estimates about 1 in 4 homes test above the EPA action level of 4.0 pCi/L, and elevated readings have turned up in all 83 counties. Locally the picture splits. Oakland County is EPA Radon Zone 2, and EGLE data shows roughly 30% of homes tested there come back high. Macomb and Wayne counties are Zone 3, the lowest category, with roughly 5–10% of Macomb County homes testing above the action level.
| Area | EPA radon zone | Homes above 4.0 pCi/L |
|---|---|---|
| Michigan statewide | Mixed | About 1 in 4 |
| Oakland County | Zone 2 | Roughly 30% of tested homes |
| Macomb County | Zone 3 | Roughly 5–10% |
| Wayne County | Zone 3 | Below the state average; elevated homes still found |
Sources: EGLE Indoor Radon Program and EGLE county estimates as reported by the Oakland and Macomb County health departments. EPA zones are county averages, not predictions for any one house.
Those are county averages. A home on one street can read safe while its neighbor reads high — it comes down to soil, construction, and the foundation. The county number tells you the odds. Only a test tells you the answer.
PreFlight uses a continuous radon monitor (CRM) placed in the lowest livable level of the home for a minimum 48-hour test under EPA protocol. Unlike a passive charcoal kit, a CRM records hourly readings, resists tampering, and produces a defensible, documented result you can act on during your inspection contingency.
You receive a clear written report with the average reading and a straightforward recommendation. If the home tests high, radon mitigation systems are effective and reasonably priced — and knowing before you close means it becomes part of the negotiation, not a surprise you inherit.
If you're buying in Oakland County — Rochester Hills, Troy, Royal Oak, Lake Orion, Auburn Hills, Oakland Township, Rochester — treat the radon test as part of the inspection, not an extra. In Macomb County the odds are lower and I'll tell you that plainly; the test is still the only way to know, and it's the one number about the house the seller can't disclose because they don't know it either.
Radon testing can be added to any home inspection or booked on its own: $175 with an inspection, $225 standalone.
Buying a home? Add this to your Complete Inspection — buyer inspection, radon, and sewer scope in one visit and one report, $749 (save $74).
Scope
What's included
Questions
Radon testing questions.
How much does a radon test cost in Metro Detroit?
$175 when it's added to a home inspection, $225 as a standalone test. That covers a continuous radon monitor placed for a minimum of 48 hours under EPA protocol, hourly data logging, and a written report with the average reading and a plain recommendation. It is also part of the $749 Complete Inspection with the buyer inspection and sewer scope.
How long does a radon test take?
A minimum of 48 hours with the monitor in place, under closed-house conditions: windows shut, exterior doors used only for coming and going. The monitor goes in at the start of the home inspection when possible and I collect it two days later. The report follows the same day I pick it up, so the whole thing fits inside a normal inspection contingency.
What is the EPA radon action level?
4.0 picocuries per liter (pCi/L). At or above 4.0 the EPA recommends mitigation. Between 2.0 and 4.0 it recommends considering it. No level is zero-risk, but 4.0 is the number lenders, buyers, and mitigation contractors all work from, and it is the number the report is written around.
Can you test for radon in the winter?
Yes, and winter is arguably the best time. Houses are closed up, the furnace is running, and the stack effect pulls more soil gas into the basement, so a winter test reflects the conditions you will actually live in. Spring and fall tests are fine too; the closed-house protocol matters more than the month.
What happens if the radon level is high?
You negotiate a mitigation system, not a walk-away. A sub-slab depressurization system, installed by a licensed radon mitigation contractor, typically brings a house well under 4.0 pCi/L, and in this area the installed cost commonly runs in the range of $800 to $1,500, though every house is different. I do not sell or install mitigation systems; I give you the number and the report and you take it to the seller.
Do new-construction homes need a radon test?
Yes. New homes are built tighter than old ones, which means soil gas that gets in has fewer places to go. Some Michigan builders install passive radon-ready piping; a passive system without a fan is not a guarantee of a low reading. A 48-hour test before your final walkthrough tells you whether the fan needs to go in while the builder is still on the hook.
Service Area
Available across Southeast Michigan
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