Radon gas mitigation: Simple strategies
If radon test results indicate that levels in your home are only slightly elevated—less than 4 pCi/L (picocuries per liter of air):
- Caulk cracks or gaps in the slab, foundation, or framing—wherever your home contacts soil—to inhibit radon gas infiltration. This step also improves the success of other radon reduction strategies.
- Open exterior crawl space vents to increase air flow and dilute radon buildup.
- Install a heat recovery ventilator (HRV). An HVR introduces fresh, air-conditioned air into homes that are otherwise tightly sealed.
Reducing radon from unsafe levels
If radon levels inside your home test at 4 pCi/L or higher, enlist the services of a professional contractor who is trained in radon mitigation strategies. Contact your state radon office for a list of contractors in your area who are trained and certified in radon reduction techniques. Obtain several bids.
Professional radon mitigation options
Some of the systems used for reducing radon are:
- Soil suction. A special vent fan draws radon from soil beneath your home through pipes that dispel gas into the open. Negative pressure created by the suction further inhibits the buildup of gas. Fans run 24/7, and are usually guaranteed for up to 10 years of continual operation.
- Sub-membrane suction. Considered the most effective strategy for homes with crawl spaces, sub-membrane suction employs a high-density plastic sheet atop the soil. A fan draws radon gas out through vent pipes located beneath the plastic.
- Passive and active ventilation. Ventilating a crawl space or adding additional vents may also reduce radon gas. Opening vents is passive ventilation; adding a fan is active. When employing either of these methods in a colder climate, you may need to add insulation in a crawl space to prevent pipes from freezing.
Costs for radon mitigation
Prices for radon mitigation vary depending on the extent of the work being done, but range between $800 and $2,500. The average cost nationally is $1,200 to $1,400.
As a rule, a house built on a slab or with a basement requires less labor, resulting in the lowest costs for radon reduction. Radon reduction in a house over a crawl space tends to be most expensive since a vapor barrier may be required.
Homes with any combination of slab, crawl space, and/or a basement fall in the middle range for costs.
Another budget consideration: As you ventilate radon gas from your home, energy costs increase—either from releasing air that’s been heated or cooled, or from you operating a fan full-time. Using an HRV to ventilate helps reduce waste.