A radon test gives you a number in picocuries per liter (pCi/L). What that number means for your home, and when to spend money on a fix, is the question this guide answers. It draws on the EPA's published advice and then shows what the work costs in the EstiCube radon calculator.
This is general information, not medical or professional advice. Your state radon office or a qualified radon professional can help with a specific reading.
What a radon reading means
The EPA describes radon as a naturally occurring radioactive gas that can cause lung cancer. You cannot see or smell it, so testing is the only way to know your level of exposure, and the EPA says all homes should be tested.
Radon is reported in pCi/L, and the EPA uses 4 pCi/L as its action level. The EPA says there is no known safe level of exposure to radon, which is why it does not treat 4 as a line between safe and unsafe.
What the EPA recommends at each level
Two bands matter in the EPA's advice. The calculator prices the same default job across both, so you can see the cost of each choice:
The table shows the calculator's default job at each level, not a tailored design. The EPA treats 4 pCi/L as the point at which to fix and the 2 to 4 band as a judgment call, so the choice in the middle band comes down to your household and how you weigh the risk. A qualified professional can talk it through with you.
| Radon level | EPA recommendation | Default job in the calculator |
|---|---|---|
| 2 to 4 pCi/L | Consider fixing the home | $1,475 |
| 4 pCi/L or higher | Fix the home | $1,475 |
| Above 20 pCi/L | Fix the home | $1,850 (adds a suction point) |
Confirm the reading first
Before you commit to a system, make sure the number is one you trust. A single result can be hard to interpret, so ask your testing professional how to confirm a first reading, especially if it falls near 4 pCi/L. That is general guidance rather than an EPA instruction.
Your state radon office is a sensible place to ask about a confusing reading or about local contractor certification. The EPA's radon pages also link to a way to find a radon test kit or a measurement and mitigation professional.
What the level does to the cost
In the calculator the reading barely changes the price. A 2,000 square foot basement home with an exterior pipe run, crack and sump sealing and a post-mitigation test is $1,475 at 3 pCi/L and at 8 pCi/L, because the system is sized by foundation and footprint. Only a reading above 20 pCi/L adds a suction point, which raises the default job to $1,850.
That matters if you are on the fence in the 2 to 4 band. Fixing at 3 pCi/L is not a cheaper, smaller system in this calculator. Real installers design from tests of the house, so use the number as a planning guide only. The system also has a running cost: about $92 a year in fan electricity at the calculator's 70-watt, $0.15 per kilowatt-hour assumptions.
After the system is installed
A test after installation is the way to confirm the level has come down, and it is usually done soon after the system is running. Ask your installer when they recommend it and whether an independent tester should do it. The calculator's $175 post-mitigation test line covers a retest like this. Some installers suggest retesting every couple of years to make sure levels stay low.
A fix is not a one-time result: the system has to keep running. Ask your installer how you can tell the fan is working, for example through a gauge or an alarm, and check it from time to time.
For a household that fixes a 2,000 square foot basement at the calculator defaults, the one-time cost is $1,475 and the fan adds about $92 a year, or roughly $920 over ten years. Fan electricity is a small running cost next to the install price, but it continues for as long as the system runs.
Choosing a professional
It is sensible to look for a certified or qualified radon mitigation contractor, get more than one estimate and contact references. NRPP, which describes itself as recognized by the EPA, credentials radon measurement and mitigation professionals and offers a search for certified professionals. Ask for proof of the credential and check what each quote includes:
- The number of suction points and why.
- Whether sealing, an electrical circuit and a post-mitigation test are included.
- The pipe route and fan location.
- How the system shows that it is running.
Run your numbers with the Radon Mitigation Cost Calculator
Change any unit price to match your quote and see every line item add up. It is free, needs no sign-up and works on your phone.
Open the Radon calculatorFrequently asked questions
At what radon level should I fix my home?
The EPA recommends fixing a home when the radon level is 4 pCi/L or higher, and says to consider fixing between 2 and 4 pCi/L. It also says there is no known safe level of exposure to radon, so talk to a qualified professional about your reading.
Does the mitigation system cost more at a higher level?
In this calculator, only above 20 pCi/L, where it adds a $375 suction point and the default job becomes $1,850. Between 2 and 20 pCi/L the default job is $1,475. Real installers design from tests of the house.
Do I need to retest after mitigation?
Yes. Testing again after the fix is how you confirm the level has come down. Ask your installer when they recommend it, and consider retesting every couple of years afterward.
How do I find a qualified radon contractor?
Look for a certified or qualified radon mitigation contractor. NRPP credentials radon professionals and has a search page. Ask for proof of credentials and get more than one estimate.
Is sealing cracks a fix on its own?
Sealing is generally treated as a supplement to a mitigation system, not a replacement. It is a $250 line in the calculator alongside the system, so ask your installer what it is expected to do.
Sources
- Radon — U.S. Environmental Protection Agency
- What is EPA's Action Level for Radon and What Does it Mean? — U.S. Environmental Protection Agency
- National Radon Proficiency Program — NRPP
More guides
