There are two basic approaches for reducing the level of radon in houses: (1) prevent radon from entering the house; and, (2) dilute radon concentrations present in the house.

No two homes have identical radon problems, so there's no single method that can reduce elevated radon levels in every home. However, there are several reduction techniques that, singly or in combination, have consistently proved effective. Homeowners should consult with a certified radon mitigation contractor about the best methods for reducing radon levels in their homes. The most frequently used remediation techniques are:

1. SUB-SLAB VENTILATION reduces the amount of radon that typically accumulates underneath a building's foundation. Pipes are inserted into holes drilled through the basement floor. The pipes are connected to an exhaust fan, which draws radon outdoors.
2. BLOCK-WALL VENTILATION is effective in cases where radon gas enters through hollow concrete walls. This ventilation method either removes radon from walls by way of an exhaust fan or prevents radon from entering walls by forcing air into the hollow spaces. Sealing cracks in basement walls will increase the effectiveness of this method.
3. SEALING OPENINGS AND CRACKS reduces the possible entry points for radon gas. Openings around utility pipes, gaps between floors and walls in basement, and large cracks in basement floors are easily identified, but there may be smaller cracks not so easily detected. This method is best when done in conjunction with other mitigation procedures.
4. COVERING EXPOSED EARTH in basements and crawl spaces with concrete or some impermeable material can help to reduce radon entry.
5. DRAIN-TILE SUCTION involves the use of a continuous loop of perforated tiles along the perimeter of a house. Either an existing drain tile system or a new system installed for this purpose will suffice. An exhaust fan is hooked to the network of tiles. The suction created by the fan pulls radon away from the surrounding soil and prevents radon from entering the house.
6. PROVIDING REPLACEMENT AIR for large home combustion appliances, such as furnaces, clothes dryers and even fireplaces, can lessen the effect of lowered air pressure typically caused by these appliances. This can reduce the amount of radon entering a home.
7. FORCED VENTILATION uses fans to increase a home's natural air exchange by drawing air into the house. As the existing indoor air leaves the house through vents or open windows, it takes the radon with it. Heat loss can be a problem during cold weather months, so ventilation techniques should be considered very carefully.
8. HEAT RECOVERY VENTILATION is a form of forced ventilation that reduces heat loss.

For all remediation work, whether done by a certified contractor or a homeowner, a post remediation test should be performed to determine if radon levels have been sufficiently lowered. A retest should be performed to determine if radon levels have been sufficiently lowered. A retest should be performed every two years to ensure that the mitigation system is still working properly.

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