You failed a radon test. Here’s exactly what to do — and what not to.
First, the reframe: “failed” just means a number crossed a recommendation line. Radon is one of the most fixable problems a house can have — a licensed contractor, one working day, and a verification test. This page walks the decision in order.
Step 1 — Read your number without flinching
EPA recommends action at 4 pCi/L and above and suggests considering action between 2 and 4. Radon risk is cumulative over years of exposure — EPA identifies radon as the leading cause of lung cancer among people who have never smoked — which is precisely why the right response is planned action, not same-day panic. A 6 is not a 60, and even a 60 is an engineering problem with a known solution.
Step 2 — Decide whether a second test earns its delay
Short-term tests are snapshots, and radon fluctuates with weather and season. So when does confirming make sense?
- No deadline, result between 2 and 8: a second short-term test (average the two) or a long-term test is reasonable diligence before spending money.
- Result well above 8: confirmation rarely changes the answer. Most households move straight to quotes.
- Inside a transaction: the contract clock usually decides for you — a written mitigation quote resolves negotiations faster than a retest standoff, and the test that matters was likely performed by a licensed measurement professional already.
Step 3 — If you’re in a deal: the 72-hour playbook
- Share the report, not adjectives. Send the actual result to your agent and attorney the day it lands; Illinois transactions run on short inspection and attorney-review windows.
- Get a real quote fast. A written quote converts “radon problem” into a line item — typically low four figures — that parties can split, credit, or absorb.
- Negotiate one of three outcomes: seller installs before closing (with a verification retest), seller credits the quoted amount, or buyer accepts and handles it after closing. All three are legitimate; Illinois requires disclosure of known results, and leaves the remedy to the parties.
Step 4 — Understand the fix you’re buying
The standard system — active sub-slab depressurization — pulls soil gas from beneath the foundation and vents it above the roof, powered by a quiet in-line fan that runs continuously. Installation is usually one day. The system is verified two ways: a manometer on the pipe showing constant draw, and a post-mitigation radon test proving the indoor number actually dropped. Details: how mitigation systems work and what they cost.
Step 5 — Hire licensed, verify independently
Illinois requires radon mitigation professionals to hold an IEMA-OHS license. Whoever you hire — through us or anywhere else — ask for the license number and check it against the state’s listings. Then compare quotes on design (suction points, routing, fan, warranty, included retest), not just the bottom line. Our licensing guide shows exactly what to verify.
Common questions
How urgent is this, really?
Radon risk accrues over years of exposure, not days — EPA frames it as a long-term lung-cancer risk, which is why its guidance is to fix elevated levels promptly but calmly. Acting within weeks is genuinely responsive. What the timeline does NOT support is ignoring a confirmed elevated result for years, or letting urgency stampede you past comparing quotes.
Can I just open basement windows or seal the cracks instead?
Ventilation dilutes radon only while windows are open — impractical in a Chicago winter — and EPA’s consumer guidance treats sealing alone as a supplement, not a reliable standalone fix, because you can never find every entry path. Active sub-slab depressurization remains the standard because it addresses the pressure physics that drive radon in.
My neighbor tested low. Could my result be wrong?
Neighboring homes routinely differ — soil gas, slab condition, and house pressure are hyper-local. If the test was conducted properly under closed-house conditions (and transaction tests by licensed measurement pros generally are), treat it as real. If you doubt the conditions, a confirming test is cheap; just don’t retest serially until you get a number you like.
Will a radon system hurt my resale value?
In this region it typically reads as a feature: a mitigated home with a documented post-installation test removes a common inspection surprise from your future sale. Illinois disclosure covers known radon information either way — a system with a good retest number is the strongest version of that disclosure.
Sources
- U.S. EPA — A Citizen’s Guide to Radon
- U.S. EPA — Health Risk of Radon
- U.S. EPA — Consumer’s Guide to Radon Reduction
- U.S. EPA — Home Buyer’s and Seller’s Guide to Radon
- IEMA-OHS — Illinois Emergency Management Agency and Office of Homeland Security — Radon Program
- Illinois General Assembly — Illinois Radon Awareness Act (420 ILCS 46)
Get the number that ends the worrying
Free quotes from up to three independent, IEMA-licensed mitigation contractors. Two minutes to request, no obligation.