Verified Radon Mitigators
For Every Transaction
When a radon contingency threatens your deal, you need a certified mitigator fast — not a guess. RadonBase lists only NRPP and NRSB verified professionals across all 50 states.
The problems agents face with radon
Deals falling through on radon contingencies
A buyer gets test results above 4 pCi/L. You need a certified mitigator booked within days — not someone who might be certified.
Proving mitigation quality to buyers
Buyers' agents want NRPP or NRSB certification numbers. RadonBase listings show the certification body, number, and expiry date — shareable in seconds.
Recommending someone you trust
Referring an unlicensed contractor creates liability. Every mitigator on RadonBase is pre-verified against official certification databases.
How RadonBase helps agents close deals
Every listing is cross-referenced against NRPP and NRSB databases before publishing. You can verify any contractor in two clicks.
Mitigators only — no testers mixed in
Other directories list radon testers under "radon professionals." A tester can measure radon but cannot install a mitigation system. RadonBase lists only certified mitigators.
Certification body, number, and expiry visible
Each listing shows whether they're NRPP, NRSB, or both certified — with their certification number and expiration date. Forward this to a buyer's agent in seconds.
All 50 states, 3,052+ verified professionals
Whether your listing is in Iowa (highest radon in the country) or coastal Florida, certified mitigators are listed for every state.
Free for agents and homeowners to search
No account required. No lead auction where 6 contractors call your client. Just find a verified mitigator and move on.
High-Risk States for Real Estate
If your listing is in these states, expect radon to come up
Iowa, Pennsylvania, Colorado, Minnesota, Ohio, Illinois, Montana, North Dakota, South Dakota, and Wyoming consistently see average indoor radon levels above the EPA action level. In these markets, radon disclosure and testing is standard practice — and buyers expect it.
Radon in real estate — common questions
What radon level requires mitigation in a real estate transaction?
The EPA action level is 4 pCi/L. Most buyers' agents and lenders treat any result at or above 4 pCi/L as requiring mitigation before or shortly after closing. Some buyers negotiate mitigation at levels above 2 pCi/L in high-radon markets.
How fast can a mitigator be scheduled?
In most markets, certified mitigators can schedule within 1–2 weeks. In high-radon states like Iowa, Pennsylvania, Colorado, and Minnesota, experienced contractors are used to real estate timelines and often offer expedited scheduling.
What documentation should buyers receive after mitigation?
A legitimate mitigator provides: a written system description, the manufacturer spec sheet for the fan installed, a manometer reading confirming negative pressure, and a post-installation radon test result (typically 48–96 hours after installation). This documentation should transfer with the home.
Does radon mitigation affect home value?
In radon-aware markets (Colorado, Ohio, Minnesota, Pennsylvania), an existing certified mitigation system is a positive selling point. Buyers in these markets often look specifically for homes with existing systems. A mitigated home is more marketable than one with an untested basement.
Who pays for radon mitigation — buyer or seller?
It's negotiable, but sellers typically pay for pre-listing mitigation. In contingency situations, the cost is often split or seller-paid as a condition of closing. Average cost is $800–$2,500 for a slab/basement job — a small number relative to a typical transaction.
Find a certified mitigator in any state
Bookmark RadonBase for your next radon contingency. 3,052+ verified mitigators, all 50 states.
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