Darien, CT Radon Mitigation and Testing

Q: What EPA Radon Zone is Darien in?

Darien is in Fairfield County, EPA Zone 1.

Q: How much does radon mitigation cost in Darien?

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

Fairfield County

EPA Zone 1

Affluent Fairfield County coastal community sits on glacial deposits and bedrock that place this area in EPA Zone 1 for highest radon potential despite its shoreline location. The town's housing stock includes many older homes with basements, along with newer construction that may include radon-resistant features. With testing data for zip code 06820 currently unavailable, residents should conduct professional radon testing to assess their individual risk levels given the area's geological characteristics.

Darien, CT Radon Mitigation

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

Darien, CT Radon Testing

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

Darien Radon Facts

Key details about the radon risk profile for Darien and the 06820 zip code area.

EPA Radon Zone

Zone 1 — High Risk

County

Fairfield County, CT

Zip Code

06820

Predicted Screening Level

> 4.0 pCi/L (Zone 1)

Darien and the 06820 zip code are located in Fairfield 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 Darien, CT

What EPA Radon Zone is Darien in?

Darien and the 06820 zip code are in Fairfield 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 Darien?

Radon mitigation in Darien 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 Darien?

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 Connecticut

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

City	Avg User Radon Level	Submissions
Hamden	4.75 pCi/L	4
West Hartford	4.25 pCi/L	4
Greenwich	7.67 pCi/L	3
Norwalk	7.00 pCi/L	1
Stamford	5.00 pCi/L	1
Middletown	4.00 pCi/L	1
Guilford	No submissions	0
Ridgefield	No submissions	0