Radon Testing & Mitigation in Chesterfield, MO

Chesterfield, MO homeowners call Air Sense Environmental for four things: radon testing, radon mitigation, indoor air quality testing and crawl space encapsulation. The NRPP-certified, IEMA-licensed (#RNM20232346) team serves St. Louis County from Edwardsville, Illinois, and designs every radon system to bring the home below the EPA action level of 4.0 pCi/L.

Is radon a problem in Chesterfield, MO?

Yes. St. Louis County is in EPA Radon Zone 2, where the predicted average indoor radon level is 2 to 4 pCi/L, and individual Chesterfield homes routinely test well above the 4.0 pCi/L action level. Missouri’s Department of Health and Senior Services reports that roughly one in three homes tested through its statewide program between 2003 and 2023 came back at or above 4.0 pCi/L. Chesterfield splits into two very different foundations: the Chesterfield Valley, the Missouri River floodplain once called Gumbo Flats, with deep silty soil, and the hills above it where 1970s to 1990s subdivisions sit on clay over bedrock.

Because radon depends on the ground under a single lot and the openings in a single foundation, Chesterfield results change from address to address. Testing the specific house is the only way to know where it stands.

Radon testing in Chesterfield, MO

For radon testing in Chesterfield, Air Sense Environmental places a continuous monitor on the lowest livable level for 48 hours and delivers a documented report against the 4.0 pCi/L action level. Radon testing in Chesterfield covers how the test works, and the radon testing cost guide holds current pricing.

Radon mitigation in Chesterfield, MO

A Chesterfield radon mitigation system pulls soil gas from beneath the slab or crawl space membrane and vents it above the roofline; every install ends with a verification test. See radon mitigation in Chesterfield for the process, documented results and warranty.

Indoor air quality testing in Chesterfield, MO

For indoor air quality in Chesterfield, a continuous monitor tracks particulates, VOCs, carbon dioxide, carbon monoxide and humidity, and the report shows which readings sit outside healthy ranges. Details are on indoor air quality in Chesterfield.

Crawl space encapsulation in Chesterfield, MO

A sealed, conditioned crawl space keeps ground moisture and soil gas from rising into a Chesterfield home; Air Sense Environmental installs the barrier, seals the vents and sizes the dehumidifier. Read more on the St. Louis crawl space encapsulation page.

Which Chesterfield homes does Air Sense Environmental work on?

The Chesterfield homes the team sees most often:

• Two-story and walkout-basement homes in the subdivisions off Clarkson Road and Olive Boulevard
• Homes in the older parts of Chesterfield built before the city incorporated in 1988
• Slab-on-grade and newer homes in and around the Chesterfield Valley
• Homes with finished basements used as bedrooms or offices, where the lowest occupied level is where people spend their time

What should Chesterfield homeowners expect?

1. Test first. A 48-hour continuous monitor test gives the number everything else depends on.
2. Read the report together. You get the hourly data and a plain explanation of what it means for the house.
3. Design the fix. If the reading is at or above 4.0 pCi/L, the system is designed around your foundation during a free in-home estimate.
4. Install and verify. Most systems go in within a single day, and a post-mitigation test confirms the result.

About Chesterfield, MO

Chesterfield is a city in St. Louis County, Missouri, United States, and a western suburb of St. Louis. As of the 2010 census, the population was 47,484, making it the state’s fourteenth-largest city. The broader valley of Chesterfield was originally referred to as “Gumbo Flats”, derived from its soil, which though very rich and silty, became like a gumbo when wet.

Chesterfield neighborhoods and nearby communities

Air Sense Environmental works across Chesterfield, MO, including Chesterfield Valley, the Clarkson Road corridor and the neighborhoods above Faust Park, in ZIP codes 63005 and 63017. Nearby communities with their own service pages:

• Radon testing and mitigation in Ballwin, MO
• Radon testing and mitigation in Maryland Heights, MO
• Radon testing and mitigation in Wildwood, MO
• Radon testing and mitigation in Creve Coeur, MO
• All Air Sense Environmental service areas

From Our Work