Most homebuyers in the Milwaukee area spend a lot of mental energy thinking about visible problems: a roof that needs replacing, an aging furnace, a basement with water stains. Radon rarely makes the list, because you can’t see it, smell it, or taste it. That invisibility is exactly what makes it one of the more serious risks in residential real estate, and why radon testing deserves a place in every home inspection conversation in southeastern Wisconsin.
What Radon Is and Where It Comes From
Radon is a naturally occurring radioactive gas that forms when uranium in soil and rock breaks down over time. It seeps upward through the ground and enters buildings through cracks in foundations, gaps around service pipes, construction joints, and other entry points. Once inside, it can accumulate to levels that pose a real health risk over time.
The U.S. Environmental Protection Agency identifies radon as the second leading cause of lung cancer in the country, responsible for an estimated 21,000 deaths annually. The risk is directly tied to concentration and duration of exposure, meaning a home with elevated radon levels becomes more of a concern the longer someone lives in it. For buyers planning to stay in a home for years or decades, knowing the radon level at purchase is important information.
Why Wisconsin Has Elevated Radon Potential
Wisconsin’s geology makes radon a legitimate concern across much of the state. The soils and underlying geology in many parts of southeastern Wisconsin, including areas of Waukesha County and communities south and west of Milwaukee, contain uranium deposits that generate radon gas. The Wisconsin Department of Health Services has identified a significant portion of the state as being in EPA Zone 1 or Zone 2, indicating moderate to high radon potential.
The region’s cold climate compounds the issue. During Wisconsin’s long winters, homes are sealed tightly against the cold, which reduces natural ventilation and allows radon to concentrate indoors. Homes that might show acceptable radon levels in warmer months can register higher readings during the heating season when windows and doors stay closed for weeks at a time.
Basements and Lower Levels
Because radon enters from the ground up, lower levels of a home tend to accumulate higher concentrations. In the Greater Milwaukee area, where finished and unfinished basements are extremely common, this matters considerably. A basement that’s used as a bedroom, home office, playroom, or living space represents a higher exposure risk than an unoccupied utility basement, simply because people are spending hours there each day.
Homes with crawlspaces present their own radon considerations. The soil beneath a crawlspace can be a significant radon source, and without proper sealing and ventilation, that gas migrates into the living areas above.
How Radon Testing Works
A radon test is straightforward and non-invasive. A test device is placed in the lowest livable area of the home, typically the basement, and left in place for the duration of the testing period. Short-term tests run for 48 to 96 hours and are the most common option during a real estate transaction. Long-term tests, which run for 90 days or more, provide a more accurate average but are less practical in a time-sensitive purchase situation.
The EPA action level for radon is 4 picocuries per liter (pCi/L). Homes testing at or above that threshold are candidates for mitigation, and the EPA recommends considering mitigation for homes testing between 2 and 4 pCi/L as well.
What Happens If Radon Levels Are High
A high radon result is not a reason to walk away from a home. Radon mitigation is a well-established process, typically involving the installation of a sub-slab depressurization system that vents radon from beneath the foundation to the exterior. In most homes, this can reduce radon levels significantly, often bringing them well below the EPA action threshold. The work is typically completed in a single day, and mitigation systems are reliable and low-maintenance.
When radon is found during a purchase inspection, buyers can negotiate with sellers to have mitigation completed before closing, request a price reduction to cover the cost, or handle the work themselves after taking ownership. Any of these paths leads to a safe outcome as long as the issue is identified.
Exploring the Greater Milwaukee Area
If you’re new to the area and going through the home buying process, the Milwaukee Art Museum on the city’s lakefront is worth a visit. The museum’s Quadracci Pavilion, designed by Santiago Calatrava, features a movable sunscreen that opens and closes like a pair of wings and has become one of the most recognizable architectural landmarks in the Midwest. It’s a striking introduction to a city that tends to surprise people who come in with modest expectations.
Frequently Asked Questions
Is radon testing required when buying a home in Wisconsin?
Radon testing is not legally required in Wisconsin real estate transactions, but it is strongly recommended. The state has significant radon potential in many areas, and buyers who skip the test have no way of knowing whether the home they’re purchasing has elevated radon levels.
How much does radon testing cost?
Radon testing added to a home inspection is a relatively modest expense compared to the overall cost of a home purchase. Contact Forever Home Inspections for current pricing for the Greater Milwaukee area.
Can a seller’s previous radon test be used instead of ordering a new one?
Generally, it’s best to conduct an independent test rather than relying on a previous result. Radon levels can vary based on season, building changes, and testing conditions. A fresh test conducted under closed-house conditions gives the most relevant snapshot of current conditions.
If a home passes a radon test, does that mean it will always be safe?
Radon levels can change over time as soil conditions shift or building modifications are made. A passing test at the time of purchase is a good sign, but periodic retesting every few years, or after major renovations, is a reasonable precaution.
Ready to schedule your home inspection and radon test in the Greater Milwaukee area? Book online with Forever Home Inspections today.