The inspection radon test came back at 4.2 pCi/L. Is that a failed test?

There is no pass or fail in the legal sense, only the EPA action level of 4.0 pCi/L. At or above it, the EPA recommends fixing the home, and most radon contingencies treat it as the trigger for a remedy. A result just over the line is treated the same way as a higher one by most contracts: the remedy is a mitigation system, and the system is the same either way.

Can I make the seller fix the radon before closing?

Only if your contract gives you that lever. A radon or inspection contingency typically lets you request a remedy, and the seller can agree, counter with a credit, or refuse. Because a system commonly costs $1,000 to $2,000 and installs in about a day, sellers usually negotiate rather than risk the deal. Your agent can tell you what is customary in your market, and your attorney can read the contingency language.

Should I walk away from a house with high radon?

High radon is one of the most fixable problems an inspection can find. A mitigation system with a documented low retest resolves it, usually within days and for $1,000 to $2,000 per WI DHS estimates. Walking away over radon alone is rare. The more useful questions are who pays for the system and whether the install and retest fit your closing timeline.

Who pays for mitigation when the buyer's test comes back high?

Wisconsin has no rule assigning the cost. It is negotiated inside the contingency: the seller installs before closing, the seller offers a credit or price reduction and the buyer handles it after closing, or the buyer absorbs it in exchange for other terms. The dollar amounts are modest next to a home price, which is why radon is usually settled rather than fought over.

Is one short-term test enough to act on?

For general homeowner testing, the EPA suggests a follow-up test to confirm a high result before spending on a system. In a transaction, the test that counts is a minimum 48-hour test under closed-building conditions, and the parties usually act on that result because the contingency clock does not leave room for a second long test. If you want certainty after closing, retest once the system is in. A post-mitigation test is standard practice anyway.

Failed a Radon Test During a Home Inspection in Wisconsin? Here Is What Happens Next

The inspection report is back on the house you are buying, and the radon line reads at or above 4.0 pCi/L. You have a contingency window measured in days, a seller on the other side of the table, and a number you may never have thought about before this week. This guide is written for exactly that moment, from the buyer's side. Badger State Radon is a free referral service, not a contractor. We connect Wisconsin buyers, sellers, and agents with independent local radon professionals, and on a deal timeline the quote is usually the step that decides whether the fix fits before closing. If you just need a professional now, skip to the form or call (608) 567-4439.

What a "failed" radon test actually means

There is no legal pass or fail. The number that matters is the EPA action level of 4.0 pCi/L: at or above it, the EPA recommends fixing the home, and between 2 to 4 pCi/L it recommends considering a fix, since no level is risk-free. Radon is worth taking seriously. It is the leading cause of lung cancer among people who do not smoke, according to the EPA and the U.S. Surgeon General. It is also worth keeping in proportion: a high reading is a task with a known price and a short timeline, not a verdict on the house. In Wisconsin it is a common task. about one in 10 homes statewide tests above the action level, 26 of the 72 counties in Wisconsin are EPA Radon Zone 1, and in some areas of Waukesha, Washington, and Dodge counties, WI DHS estimates as many as 60% of homes could have main-floor radon above EPA guidelines, per WI DHS. Buyers and agents here see radon on inspection reports all the time, and the market has settled ways of resolving it.

One thing to check before negotiating: how the test was run. For a transaction, the result that counts comes from a minimum 48-hour test under closed-building conditions, with the house closed at least 12 hours before the test starts and kept closed throughout. Home inspectors typically follow that protocol. If the test was run with windows open or ran shorter than 48 hours, the number is arguable, and your agent may want it redone. Our radon test results guide covers how to read the number itself.

The contingency clock you are on

In most Wisconsin purchases, radon is tested inside the inspection contingency, the window your offer gives you to investigate the home and raise issues. That window is the deadline that shapes everything. A high result typically leaves days, not weeks, to notify the seller, agree on a remedy, and in many cases get the work done and retested before the closing date. The EPA's Home Buyer's and Seller's Guide to Radon walks through how radon fits a transaction timeline. The practical translation: do not spend the first three days of a 10-day window searching for a contractor. Line up the professional first, then negotiate with a real quote and a real install date in hand.

Your options as the buyer

There is no Wisconsin rule that assigns the cost of mitigation. Everything is negotiated inside the contingency, and the outcomes cluster into four patterns:

Seller fixes it before closing. The seller hires a radon professional, the system goes in, and a follow-up test documents the level dropped below 4.0 pCi/L. Cleanest for you, because you close on a mitigated house with a number to prove it.
Credit or price reduction. The seller offsets the cost and you arrange the work after closing. WI DHS estimates a contractor-installed system typically runs $1,000 to $2,000, so the credit math is straightforward. You control the contractor choice; you also carry the follow-up.
Escrow holdback. Funds are held at closing for the work when the calendar is too tight for install plus retest. Whether a lender allows it depends on the loan, so ask early.
You absorb it. In a competitive market some buyers accept the reading as-is and budget the fix themselves. That is a market decision, not a radon decision, and it works because the fix is reliable.

Which pattern fits depends on your market, the size of the reading, and how your offer was written. Your agent knows what is customary; your attorney reads the contingency. If you are on the other side of this deal, the seller's version of this situation is covered in selling a house with high radon in Wisconsin.

The fix is faster than the negotiation

The fact that makes all four options workable: the standard fix, an active sub-slab depressurization system, is frequently a one-day install, and it works. A sealed suction pipe and an inline fan pull soil gas from beneath the foundation and vent it above the roofline. After the install, a follow-up test confirms the level dropped, and that retest is the document most buyers and lenders want to see. Details are on the radon mitigation page, the deal-specific timing on radon mitigation at a home sale, and the cost drivers in the Wisconsin radon mitigation cost guide.

After you get the keys

If a system went in before closing, keep the retest result with your closing documents. It answers the question for your own records and again whenever you sell. If you took a credit instead, schedule the install soon after moving in rather than letting it drift; the system costs the same either way, and the level does not improve on its own. Either way, the EPA suggests retesting every two years and after major renovations. Wisconsin's 17 Radon Information Centers sell low-cost test kits, reachable at 1-888-LOW-RADON (1-888-569-7236). Kit prices change, so check that page for current details.

Getting your quote inside the window

When the contingency is running, the bottleneck is almost never the work. It is finding a professional who can quote, install, and retest inside the window. That is the part Badger State Radon compresses. Tell us the city or county, the closing date, and the test result, and we connect you with an independent local radon professional, usually the same day. We do not perform the work, hold no radon certification, and never vouch for a credential we cannot confirm. You compare the quote and the plan yourself, and there is never a cost to you or an obligation to hire anyone we introduce. Agents and inspectors who handle this weekly can use the same channel: see for real estate agents and home inspectors.