Radon and Basement Waterproofing in Iowa: One Plan, Not Two

Iowa HHS reports that the Iowa Radon Survey found 71.6% of homes above the EPA action level of 4 pCi/L, the largest share of any state, and EPA designates all of Iowa as radon zone 1. In a Des Moines basement, the same openings let in water and soil gas: cracks, the joint between wall and floor, and an open sump pit.

Test first. A short-term kit costs about $10 to $50 and a professional test $125 to $400 (HomeGuide, 2026). See radon testing. Test in the lowest lived-in level with windows closed.

Plan the order. If you need drain tile and the radon test is high, tell both providers, or use one that does both. A drain loop under the floor can serve as the suction path for a radon fan, and a sealed, gasketed sump lid is needed either way.

Ask about the pipe route. A radon system vents above the roof. Inside routes run through a closet or the garage; outside routes run up an exterior wall. Ask where it will go, how loud the fan is, and where the manometer will be mounted.

Retest. After the basement work and the radon system are finished, test again. Keep the results: under Iowa law, a seller must disclose known radon tests (Iowa HHS).

Credentials. Iowa HHS runs credentialing for radon testers and mitigation specialists. Ask for the credential before you sign.