Radon Mitigation in O’Fallon, IL

A radon mitigation system in O’Fallon, IL 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 O’Fallon system around the foundation in front of it.

Does a O’Fallon home need radon mitigation?

The trigger is the test result: at or above 4.0 pCi/L the EPA recommends fixing a O’Fallon home, and between 2 and 4 pCi/L it suggests considering it. St. Clair County is in EPA Radon Zone 2, where the predicted average indoor radon level is 2 to 4 pCi/L, and individual O’Fallon homes routinely test well above the 4.0 pCi/L action level. The Illinois Department of Public Health reports that about 41 percent of Illinois homes tested have come back at or above 4.0 pCi/L, and Illinois requires radon professionals to hold an IEMA license.

O’Fallon, Illinois grew quickly from the 1990s onward around Scott Air Force Base, so most of its housing is newer subdivision construction, which does not exempt it: tight, energy-efficient homes hold radon indoors longer than drafty older ones. If the home has not been tested yet, start with radon testing in O’Fallon.

Which radon mitigation system fits a O’Fallon home?

The system follows the foundation:

• Basement slab: sub-slab depressurization, the most common system in O’Fallon
• 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 O’Fallon homes Air Sense Environmental mitigates most often:

• 1990s and 2000s two-story homes on poured basements in the subdivisions off Highway 50 and Green Mount Road
• Homes bought and sold on military timelines near Scott Air Force Base, where real estate testing is routine
• Ranch homes in the older core near downtown O’Fallon
• Slab-on-grade villas and townhomes, where the slab itself is the radon pathway

How is a radon mitigation system installed in O’Fallon?

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 O’Fallon 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 O’Fallon, IL?

Foundation type, suction points and fan size set the price of a O’Fallon 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 O’Fallon 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.

O’Fallon neighborhoods and nearby communities

Air Sense Environmental works across O’Fallon, IL, including downtown O’Fallon, the Highway 50 corridor and the subdivisions between O’Fallon and Scott Air Force Base, in ZIP code 62269. Nearby communities with their own service pages:

• Radon mitigation and testing in Belleville, IL
• Radon mitigation and testing in Fairview Heights, IL
• Radon mitigation and testing in Swansea, IL
• Radon mitigation and testing in Troy, IL
• All Air Sense Environmental service areas

From Our Work