Got a High Radon Result? Here's How We Fix It.

Radon Mitigation in Eau Claire County

Radon is a naturally occurring radioactive gas that seeps up out of the soil and into homes through the foundation. You can't see it or smell it, and the only way to know your level is to test — but once a test comes back high, the fix is well-established and highly effective. The U.S. EPA recommends taking action to reduce radon at 4.0 pCi/L (picocuries per liter) or higher, and suggests considering a fix between 2.0 and 4.0. A properly designed mitigation system reliably brings most homes well below that action level.

How radon gets into a home

Radon comes from the natural breakdown of uranium in soil and rock. The gas moves up through the ground and, because a heated house is slightly lower in pressure than the soil around it, the home actually draws that soil gas in — through cracks in the slab, floor-wall joints, sump pits, crawlspaces, and around plumbing penetrations. That's why radon collects in the lowest levels of a house, and why the fix focuses on the foundation.

Active sub-slab depressurization — the proven method

The most common and effective mitigation method is active sub-slab depressurization (ASD). The idea is straightforward: instead of letting the house pull radon in, we create a zone of lower pressure under the slab so the gas is drawn away before it ever enters the living space. A typical system involves:

• A suction point — a hole cored through the slab into the crushed rock or soil beneath, sometimes with a small pit excavated to improve airflow.
• Sealing — visible cracks, the floor-wall joint, and any open sump are sealed so the system pulls from under the slab rather than short-circuiting through gaps in the floor.
• Vent piping — PVC pipe routed from the suction point up through the house (or along the exterior) and terminating above the roofline, away from windows, so the gas disperses safely outdoors.
• An inline radon fan — mounted in an attic or outside (never in the living space, per standards) — runs continuously and quietly, maintaining the suction.
• A manometer — a simple U-tube pressure gauge on the pipe that lets you see at a glance that the fan is doing its job.

Foundation type changes the design

Not every home takes the same system. A poured basement slab is the textbook case for sub-slab depressurization. A crawlspace is usually handled with sub-membrane depressurization — a sealed heavy plastic membrane laid over the soil with suction drawn beneath it. Homes with multiple foundation types (a slab addition off a basement, say) sometimes need more than one suction point or more than one system. Part of the job is looking at your specific foundation and designing the system that will actually pull the level down.

What drives the cost

There's no single price because no two homes are identical. The factors that move the number: foundation type (a simple basement slab is the low end; crawlspaces and mixed foundations cost more), how far the vent pipe has to travel to reach above the roofline, how many suction points the home needs to hit the target level, and whether the routing is interior (through closets/garage) or exterior. We look at the home and give you a real number before any work begins.