Colby, WI Radon Mitigation and Testing

Q: What EPA Radon Zone is Colby in?

Colby is in Marathon County, EPA Zone 1.

Q: How much does radon mitigation cost in Colby?

Radon mitigation typically costs between $800 and $2,000. Most standard systems fall in the $1,000-$1,500 range.

Marathon County

EPA Zone 1

Nestled in central Wisconsin's Marathon County, Colby sits within EPA Zone 1 where glacial deposits over Precambrian bedrock create conditions highly favorable for radon accumulation. The community's housing includes older farmhouses and modern residential construction around 54421, most featuring basement foundations typical of Wisconsin homes. With limited local testing data available, homeowners should conduct radon assessments to determine if levels exceed EPA action thresholds common throughout this geological region.

Colby, WI Radon Mitigation

Professional radon mitigation is the most effective way to permanently lower radon levels and protect your household.

Colby, WI Radon Testing

Finding qualified radon testing professionals is the first step toward protecting your home.

Colby Radon Facts

Key details about the radon risk profile for Colby and the 54421 zip code area.

EPA Radon Zone

Zone 1 — High Risk

County

Marathon County, WI

Zip Code

54421

Predicted Screening Level

> 4.0 pCi/L (Zone 1)

Colby and the 54421 zip code are located in Marathon County, which has an EPA assigned Radon Zone of 1. A radon zone of 1 predicts an average indoor radon screening level greater than 4 pCi/L. The EPA recommends testing every home regardless of zone classification.

Radon FAQ for Colby, WI

What EPA Radon Zone is Colby in?

Colby and the 54421 zip code are in Marathon County, which has an EPA assigned Radon Zone of 1. A zone of 1 predicts an average indoor radon screening level greater than 4 pCi/L.

How much does radon mitigation cost in Colby?

Radon mitigation in Colby typically costs between $800 and $2,000. Most homes with standard basements can be mitigated with a sub-slab depressurization system in the $1,000–$1,500 range. Factors that can increase cost include complex foundations, crawl spaces, or very high radon levels.

Should I test for radon if I'm buying a home in Colby?

Yes. Radon testing should be part of every home purchase. A short-term radon test is typically included as part of the home inspection process and costs $150–$250. If elevated levels are found, you can negotiate mitigation as part of the sale.

Most Active Radon Markets in Wisconsin

Cities with the most user-submitted radon test data in the state.

City	Avg User Radon Level	Submissions
Milwaukee	10.00 pCi/L	3
Prairie Du Chien	10.00 pCi/L	2
Stevens Point	5.50 pCi/L	2
Menomonie	10.00 pCi/L	1
Delavan	6.00 pCi/L	1
Shawano	No submissions	0
Sturgeon Bay	No submissions	0