What does Iowa law say about radon disclosure when selling a home?

Iowa law requires sellers to disclose known radon test results as part of the state's mandatory real estate disclosure process. In plain terms, if a seller has ever tested the home and knows the result, that result must be shared with buyers; a seller cannot quietly shelve a bad radon number. What the law does not do is require testing: an Iowa seller who has never tested has nothing to disclose, and no Iowa law requires a home inspection before a sale (the one mandatory time-of-transfer inspection covers private septic systems), so nothing forces the issue. In the state with the largest percentage of homes above the EPA action level, where Iowa HHS puts that figure at 71.6 percent, that gap means many homes change hands with radon status simply unknown. For buyers, the practical takeaway is to read the seller disclosure carefully, ask directly whether the home or any mitigation system has been tested, and then order your own 48-hour test during the inspection period regardless of the answer, since radon levels can change and old results go stale. For sellers, testing before listing can be a genuine advantage: a passing result reassures buyers, and if the number is high, installing mitigation on your own timeline is easier than negotiating it under contract deadlines. Radon measurement is available as an add-on across Iowa, with every result documented in writing, ready to hand to either side of the transaction.