Eau Claire Radon Mitigation: Radon Mitigation Services in Eau Claire, Wisconsin

In a large commercial building, suction has to reach across a big footprint, well beyond one mechanical room or slab section. We design multi-point active soil depressurization systems with several balanced suction points and a commercial-grade radon fan. A pressure-field extension test then confirms that each point draws across its assigned area. To prevent pressure conflicts, we coordinate the system with the building's HVAC and make-up air. The vent stacks discharge above the roofline, and the build follows the ANSI/AARST mitigation standard for schools and large buildings (SGM-MFLB).

Apartments and condominiums need a per-building plan because they have shared foundations and separate living spaces. We test each unit, focusing on ground-contact units and common areas. When slab sections are connected, they can share one sub-slab system, while a zoned layout provides separate control where foundations differ. Fans and piping route away from tenant space. HUD radon requirements set testing and mitigation duties for HUD-backed properties, and after the system is installed, a per-unit retest confirms the result in each unit.

Exposed soil in a crawl space has to be sealed before a fan can pull radon effectively. We lay a continuous 6-mil polyethylene vapor barrier, or a heavier sheet where storage and foot traffic call for it. We tape the seams and seal the edges to the foundation, which also encapsulates the crawl space and cuts soil moisture. A sub-membrane system then draws radon from beneath the barrier. Before we finish, we confirm that the barrier is holding suction.

Sub-slab depressurization is the core active method for a concrete floor, drawing radon from beneath the slab. We cut a suction pit through the slab to reach the gravel layer (aggregate) below. We then seal the penetrations, joints, and sump cover so basement air does not weaken the draw. A continuous radon fan, which many homeowners call a radon pump, drives the radon vent system by pulling soil gas up a PVC stack to a discharge above the roofline. A manometer shows that the system is holding suction. Added suction points cover a larger or divided slab.

A basement that tests high is the most common radon problem we solve. We fit a sub-slab system, seal the paths radon takes into the finished space, and retest to confirm the drop. Radon can reach your basement through foundation cracks and control joints, the slab-wall edge, utility penetrations, and an unsealed sump. Closing those routes supports the suction under the slab. In a finished basement, we plan the pipe route to keep the visible run tidy. Most homes are finished in a day, and you get a quiet fan, a manometer, and a documented result.

A full installation gives you a complete, tested radon reduction system designed for your specific house. We size the system from the radon reading and the foundation, then choose interior or exterior routing that fits the layout and the look of the house. As part of the build, we seal the openings, label the system, and mount a monitor. The fan itself mounts in an attic, a garage, or outdoors, never in or below living space, so any leak on its pressure side — the piping after the fan — stays outside the rooms you live in. We follow ANSI/AARST guidance for discharge placement so exhaust clears windows and living space. After installation, a test documents the reduction on paper.

Adding radon control during a build is far cheaper while the foundation is still open. Radon-resistant new construction begins with a layer of gas-permeable aggregate under the slab and a vapor retarder above it, while penetrations are sealed as the work goes in. A capped vent stack runs from that layer up through the house, and the entire system is built to current code. If post-occupancy testing later finds elevated radon, a fan can be added to activate the system.

Owners and lenders need a clear picture of radon throughout a large building, and one test in a single room cannot provide it. We lay out a device placement grid according to the floor area, ground contact, and how each space is used. The ANSI/AARST measurement protocol for large buildings sets the device density. Continuous radon monitors record readings over the measurement period under closed-building conditions, with doors and windows kept shut. Every reading maps back to its area, ready for mitigation planning, a property review, or follow-up testing.

Some homes already have a passive stack, which is a vent pipe running from under the slab to the roof without a fan. To find out whether it can be activated, we confirm that the stack reaches a proper discharge and seal any gaps left around it. We then add an in-line radon fan sized to the pipe. The fan changes the stack’s natural airflow into steady mechanical suction, while a monitor lets the homeowner see that the system is working. Afterward, a test shows how far the activated system reduced the home’s radon.

A worn-out fan, a cracked or separated pipe joint, or a leaking sump cover can cause an older system to lose suction. We first read the manometer to see whether the system still holds the right pressure difference. A failed or noisy fan gets replaced, cracked fittings are resealed, and a loose sump cover is closed up. Because radon fans typically last about ten years of continuous running, replacement is normal maintenance. Once suction is restored, a retest confirms that the repair worked.

During a property transaction, buyers, sellers, and inspectors need a prompt result they can document. We run a 48-hour continuous-monitor test for real estate transactions, recording readings throughout the measurement period and flagging any device movement. The monitor runs under closed-house conditions to provide a defensible result, and we schedule placement and pickup around the transaction timeline and inspection deadline. The completed report identifies the test location, measurement period, average concentration, and monitor data for the sale file.

The right radon test depends on how soon you need an answer and how much seasonal variation you want the result to capture. A charcoal canister test provides a quick screening result. An alpha-track detector runs a 91-day long-term test and can stay in place for up to a year, averaging radon levels across seasons. When you need the fastest logged reading, a continuous radon monitor records hourly data. We compare the result with the 4.0 pCi/L action level and confirm an elevated short-term reading before recommending a mitigation system.