Radon Mitigation Systems in Columbus

A radon system turns the pressure difference around. A heated house sits at slightly lower pressure than the soil beneath it, most of all through a long zone 5A winter, so soil gas drifts in through whatever openings the foundation offers. A sub-slab system cores a small suction pit through the floor, connects it to sealed pipe, and runs a fan that keeps the soil under the slab at lower pressure than the room above. The gas takes the pipe instead of the floor and leaves above the roofline.

The EPA's Consumer's Guide to Radon Reduction puts active sub-slab suction at 50 to 99 percent reduction, which is why it is the default for basements and slabs. Crawl spaces get the same idea beneath a sealed membrane. Sealing plays a supporting role: Ohio's standards require the floor-wall joint, cracks, and utility openings to be closed so the fan draws from the soil rather than from the basement, and the EPA treats sealing on its own as a partial measure.

The difference between a system that holds its number and one that drifts is usually decided before the first hole is cut. Ohio requires a visual inspection recorded on a floor plan drawing, and a communication test wherever the material under the slab is unknown, which on Central Ohio clay till and patched older floors is most of the time. Our pricing guide by foundation type shows how those findings turn into scope.

Ohio regulates this trade directly. The Ohio Department of Health licenses the company as a mitigation contractor and the person who designs and supervises the job as a mitigation specialist, and the appendix to OAC 3701-69-08 sets the installation rules. Several are easy for a homeowner to check.

The fan lives in an attic, in a garage that is not under living space, or outside, never in a basement or a lived-in room, and it sits in a vertical run on removable couplings. The discharge ends above the highest eave, at least 12 inches above the roof surface, at least 10 feet above the ground, and at least 10 feet from any window or door less than 2 feet below it and from openings into a neighboring building. No rain cap. The main pipe is at least 3 inches across. An exterior fan is hard-wired with a disconnect within sight and within 4 feet of it.

Every active system carries a monitor or gauge, and a manometer is marked with its reading at start-up. RADON REDUCTION SYSTEM labels go on exposed pipe on each floor, on the exterior fan, and on the breaker. A covered sump must be airtight, fitted with a view port, strong enough to stand on, and sealed with silicone so the pump can still be serviced. Where natural-draft gas appliances share the basement, a backdraft test follows activation. The standard itself says compliance does not guarantee a particular number; what it does guarantee is a system the next inspector can read.

The geology sets the odds and the house sets the design. The Ohio Shale, which the USGS describes as the largest uranium source in the state, runs in a north-south band beneath Franklin and Delaware counties, and Franklin County's 16,142 pre-mitigation tests from 2008 to 2017 had an estimated mean of 9.5 pCi/L in an American Lung Association analysis of CDC data. Nearly every foundation type in the region sees elevated results.

Older neighborhoods bring the hard cases. Brick houses in German Village and Victorian Village and the 1910s to 1940s streets of Clintonville often have stone or block walls, floors poured in sections, and years of patches, so they need more sealing and sometimes a second suction point. Tight lots make the 10-foot rule around neighbors' openings a real routing constraint. Postwar ranches in Whitehall and Reynoldsburg mix slabs, crawls, and partial basements, and Ohio's testing protocol calls for measuring each foundation type.

Newer subdivisions in Dublin, Hilliard, Powell, Lewis Center, New Albany, and around the Intel site near Johnstown usually have poured basements or slabs that are straightforward to mitigate, and some already have a builder's passive pipe that only needs a fan. Rural lots in Delaware, Union, and Licking counties add a second question: whether the private well contributes radon too.

Most Central Ohio basement and slab systems fall between $1,200 and $2,400; crawl spaces with a sealed membrane run $1,800 to $3,500. Under Ohio's standards, nothing is installed until you sign a written proposal, and that proposal has to list the Ohio license numbers of the specialist and the contractor, the scope and estimated completion date, any chemical hazards, a statement of compliance with the Ohio standards, the maintenance you are responsible for, the installed price, an estimate of annual operating cost, and either a guarantee to bring the average below 4 pCi/L with its conditions or an explanation of why no guarantee is offered.

If the same company tested your house, the contract must say so and must point out the value of long-term testing and a second opinion. When the job is finished, the closeout package should hold the floor plan drawing, pre- and post-mitigation results, contracts and warranties, a description of the system and how it works, instructions for when the alarm trips, and the installer's name, phone, and license number.

The post-mitigation test belongs between 24 hours and 30 days after the fan starts, run by the installing specialist or an independent Ohio-licensed tester, and Ohio installers must advise retesting at least every two years. See what an Ohio proposal must include or use the calculator for a starting range.