Griswold, IA Radon Levels

Q: What is the average radon level in Griswold, IA?

Based on 1 user-submitted tests, the average radon level is 20.00 pCi/L.

Q: What EPA Radon Zone is Griswold in?

Griswold is in Cass County, EPA Zone 1.

Q: How much does radon mitigation cost in Griswold?

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

Check local Griswold radon levels and find certified testing and mitigation professionals to keep your home safe

Griswold, IA Radon Facts

EPA Radon Zone Zone 1 — High Risk > 4.0 pCi/L (Zone 1)

County Cass County, IA

Zip Code 51535

Avg. User Level 20.00 pCi/L

User Tests 1

Griswold sits in Cass County within Iowa's Omaha Metro area, where glacial soils and underlying bedrock geology contribute to significant radon potential. Current testing data shows an average radon level of 20.0 pCi/L, which substantially exceeds the EPA's 4.0 pCi/L action level and indicates immediate mitigation is strongly recommended. The community's housing stock, typical of rural Iowa with many homes featuring full basements, provides enclosed spaces where radon can concentrate to dangerous levels in zip code 51535.

20.00

pCi/L average

Above EPA Action Level

Based on 1 user-submitted radon test for homes in Griswold, IA. The EPA recommends taking action at or above 4.0 pCi/L.

4.0 EPA

10+

Griswold, IA Radon Mitigation

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

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Griswold, Iowa Radon Levels

User-submitted radon test readings from homes in the Griswold area.

Radon Level	City	Home Age	Foundation	Submitted
20 pCi/L	Griswold, IA	0-20 Years	Full Basement	Mar 2025

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Radon FAQ for Griswold, IA

What is the average radon level in Griswold, IA?

Based on 1 user-submitted test, the average radon level in Griswold is 20.00 pCi/L. This exceeds the EPA's recommended action level of 4.0 pCi/L, and radon testing is recommended for all homes in the area.

What EPA Radon Zone is Griswold in?

Griswold and the 51535 zip code are in Cass 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 Griswold?

Radon mitigation in Griswold 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 Griswold?

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 Iowa

Cities in Iowa with the most user-submitted radon test data, ranked by number of submissions.

City	Avg User Radon Level	Submissions
Waterloo	8.50 pCi/L	4
Ames	9.67 pCi/L	3
Fairfield	14.00 pCi/L	2
Mount Pleasant	12.00 pCi/L	2
Ottumwa	5.50 pCi/L	2
Iowa City	7.00 pCi/L	1
Muscatine	No submissions	0