Radon Mitigation in Webster Groves, MO

A radon mitigation system in Webster Groves, MO is a sealed pipe and a continuously running fan that pull radon from under the house and release it outdoors, bringing the home below the EPA action level of 4.0 pCi/L. Air Sense Environmental, IEMA-licensed (#RNM20232346) and NRPP-certified, designs each Webster Groves system around the foundation in front of it.

Does a Webster Groves home need radon mitigation?

The trigger is the test result: at or above 4.0 pCi/L the EPA recommends fixing a Webster Groves home, and between 2 and 4 pCi/L it suggests considering it. St. Louis County is in EPA Radon Zone 2, where the predicted average indoor radon level is 2 to 4 pCi/L, and individual Webster Groves 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.

Webster Groves is one of the oldest suburbs in St. Louis County, where 1890s to 1930s homes around Old Webster sit on stone and early poured foundations with cellars and partial basements. If the home has not been tested yet, start with the St. Louis radon testing page.

Which radon mitigation system fits a Webster Groves home?

The system follows the foundation:

• Basement slab: sub-slab depressurization, the most common system in Webster Groves
• Crawl space: sub-membrane depressurization under a sealed vapor barrier
• Sump pit: a sealed sump lid tied into the system, covered in the sump pump radon mitigation guide
• Slab-on-grade: a suction point routed through a garage, closet or exterior wall
• Mixed foundations: multiple suction points balanced on one fan

The Webster Groves homes Air Sense Environmental mitigates most often:

• 1890s to 1930s homes near Old Webster with stone foundations
• 1920s bungalows with partial basements and crawl spaces
• Mid-century ranches with finished basements
• Additions built over crawl spaces on older homes

How is a radon mitigation system installed in Webster Groves?

1. Assessment and diagnostics. The foundation, sump, cracks and pipe route are checked during a free in-home estimate.
2. Suction point. A core hole through the slab, or a sealed membrane in a crawl space, gives the fan something to pull from.
3. Pipe and fan. PVC pipe runs to a fan mounted outside the living space, in the attic, garage or on an exterior wall, and vents above the roofline.
4. Sealing. Cracks, the sump lid and other openings are sealed so the fan can hold suction.
5. Manometer and verification. A U-tube manometer shows the system is running, and a post-mitigation test proves the result.

Most Webster Groves installations are completed in a single day. The full walk-through is on the radon mitigation system installation page.

How much does radon mitigation cost in Webster Groves, MO?

Foundation type, suction points and fan size set the price of a Webster Groves system, which is why quotes follow a free in-home assessment. The St. Louis radon mitigation cost guide lists the current ranges by system type.

How do you know the radon mitigation system worked?

A post-mitigation radon test is the only proof. Air Sense Environmental includes it, designs Webster Groves systems to a target well below the 4.0 pCi/L action level, and recommends retesting every two years. When a fan eventually wears out, radon fan replacement restores the system.

Webster Groves neighborhoods and nearby communities

Air Sense Environmental works across Webster Groves, MO, including Old Webster, Old Orchard and the neighborhoods around Webster University, in ZIP code 63119. Nearby communities with their own service pages:

• Radon mitigation and testing in Kirkwood, MO
• Radon mitigation and testing in Rock Hill, MO
• Radon mitigation and testing in Maplewood, MO
• Radon mitigation and testing in Affton, MO
• All Air Sense Environmental service areas