Radon Testing & Mitigation in Weldon Spring, MO

Air Sense Environmental provides radon testing, radon mitigation, indoor air quality testing and crawl space encapsulation in Weldon Spring, MO. The company is IEMA-licensed (#RNM20232346) and NRPP-certified, works across St. Charles County from its Edwardsville, Illinois headquarters, and measures every radon job against the EPA action level of 4.0 pCi/L.

Is radon a problem in Weldon Spring, MO?

Yes. St. Charles County is in EPA Radon Zone 2, where the predicted average indoor radon level is 2 to 4 pCi/L, and individual Weldon Spring 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. Weldon Spring is a small St. Charles County city of newer, larger homes on rolling ground next to the August A. Busch Memorial Conservation Area.

Radon varies house by house rather than neighborhood by neighborhood. Two homes on the same Weldon Spring street, built the same year by the same builder, can test at 1 pCi/L and 12 pCi/L because of what sits under each lot and how each foundation was sealed.

Radon testing in Weldon Spring, MO

Radon testing in Weldon Spring uses a calibrated continuous radon monitor for a 48-hour closed-house test, with hourly readings and tamper detection that hold up in a real estate transaction. The St. Louis radon testing page covers how the test works, and the radon testing cost guide holds current pricing.

Radon mitigation in Weldon Spring, MO

Radon mitigation in Weldon Spring means a sub-slab depressurization system designed around the specific foundation, with the fan outside the living space and a post-mitigation test to prove the result. See the St. Louis radon mitigation services page for the process, documented results and warranty.

Indoor air quality testing in Weldon Spring, MO

Indoor air quality testing in Weldon Spring measures particulates, VOCs, carbon dioxide, carbon monoxide, temperature and humidity over at least 48 hours, with radon as an optional add-on, and ends in a written report. Details are on the St. Louis indoor air quality testing page.

Crawl space encapsulation in Weldon Spring, MO

Crawl space encapsulation in Weldon Spring seals the floor and walls with a reinforced vapor barrier, closes the vents and controls humidity with a dehumidifier, which also cuts off a common radon pathway. Read more on the St. Louis crawl space encapsulation page.

Which Weldon Spring homes does Air Sense Environmental work on?

The Weldon Spring homes the team sees most often:

• 1990s to 2010s homes on poured basements, many with finished lower levels
• Walkout-basement homes on sloped lots
• Homes on larger lots with private wells
• New construction, which should get a baseline test even with a passive radon pipe

What should Weldon Spring 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.

Weldon Spring neighborhoods and nearby communities

Air Sense Environmental works across Weldon Spring, MO, including the Highway 94 corridor and the subdivisions near the August A. Busch Memorial Conservation Area, in ZIP code 63304. Nearby communities with their own service pages:

• Radon testing and mitigation in O’Fallon, MO
• Radon testing and mitigation in St. Charles, MO
• Radon testing and mitigation in St. Peters, MO
• Radon testing and mitigation in Chesterfield, MO
• All Air Sense Environmental service areas

From Our Work