Radon Mitigation in Janesville, WI
Janesville anchors Rock County in south-central Wisconsin, where the Rock River runs past a downtown lined with older homes and where newer subdivisions have spread toward the edges of the city. The EPA places Rock County in Radon Zone 1, the higher of the two EPA categories that apply in Wisconsin (predicted average indoor level at or above 4 pCi/L). Whether you are relocating into the area, listing a house, or just settling in after a move, Badger State Radon connects Janesville homeowners with independent local radon professionals. We are a free matching service, not a contractor, and this page lays out what radon looks like here and what to do about a reading.
Radon in Janesville and Rock County
Rock County is EPA Radon Zone 1, the higher of the two EPA categories that apply in Wisconsin (predicted average indoor level at or above 4 pCi/L), cited to the EPA Map of Radon Zones. The local housing stock is a range of older near-downtown homes and newer subdivisions along the Rock River, and older and newer homes alike can test high because radon is driven by the soil beneath the foundation, not the age of the house. Zone 1 is a county-wide screening prediction, so your street and even your next-door neighbor can differ. Statewide, WI DHS reports that about one in 10 Wisconsin homes tests above the action level, and readings vary widely from address to address. Rather than lean on any single county figure, check how homes near you have actually tested on the WI DHS radon results map, which breaks reported results down to the ZIP level. The reliable move is still to test your own home.
Testing your Janesville home
For Janesville and the surrounding area, the regional Radon Information Center serves Rock County, and statewide 17 Radon Information Centers offer kits for about $15 including lab analysis. A short-term charcoal test takes just a few days, which suits a pending sale, while a long-term test gives a better year-round average. Winter is peak testing season here, since closed-up homes let radon build. If a short-term test comes back at or above 4.0 pCi/L, the EPA recommends confirming with a follow-up test. You can also reach the state radon line at 1-888-LOW-RADON (1-888-569-7236). See radon testing for the full rundown on kits, timing, and closed-building conditions.
Mitigation and cost
If your level is high, the common fix is active sub-slab depressurization: a pipe and a continuously running fan that draws radon from under the slab and vents it above the roofline. Sealing cracks alone is not a complete fix. Wisconsin DHS estimates a contractor-installed system typically costs $1,000 to $2,000, and Janesville homes fall in that range depending on foundation type and system design, with ongoing cost mainly the a few dollars a month fan electricity. Learn how systems work on the radon mitigation page, and see the Wisconsin cost guide for the breakdown. The independent professionals we match you with can hold the voluntary NRPP or NRSB credentials; we do not perform the work or hold any certification ourselves.
Radon and a Janesville home sale
Janesville is a common relocation and home-sale market, and in a Rock County transaction radon is usually tested during the inspection contingency. A high result moves fast: it tends to leave days, not weeks, before closing, systems often install within a few days, and who pays is negotiable between buyer and seller. Our page on radon mitigation at a home sale covers the Wisconsin disclosure and how the timing usually plays out. For the statewide picture, from action levels to county zones, the Wisconsin radon guide ties it all together. If a test just came back high or a deadline is bearing down, a quick match with a local professional is the fastest way forward.