Why Should You Build Homes with Radon Resistant Techniques?

New Homes can be Built with Radon-Resistant Features

Radon-resistant construction techniques can be effective in preventing radon from entering a site. When they are installed properly and completely, these simple and inexpensive techniques can help reduce indoor radon levels in homes. Also, installing them at the time of construction makes it easier and much less expensive to reduce radon levels further if these passive techniques do not reduce radon levels to below 4 pCi/L. Even if it was built radon-resistant, every new home should be tested after occupancy. If radon levels stay in excess of 4 pCi/L, the passive system should be activated by having a qualified mitigator to install a vent fan.

What are Radon-resistant Construction Techniques?

The methods vary for differing foundations and site requirements, but the basic elements are:

  1. Gas Permeable Layer
    This layer is placed under the slab or flooring system to permit the soil gas to move freely below the house. In many cases, a 4-inch layer of clean gravel is the material used.
  2. Plastic Sheeting
    Plastic sheeting is set on top of the gas permeable layer and beneath the slab to help prevent the soil gas from coming into the home. In crawlspaces, the sheeting is then placed over the crawlspace floor.
  3. Sealing and Caulking
    All openings in the concrete foundation of the floor are sealed to reduce the soil gas entry into the home.
  4. Vent Pipe
    A 3 or 4 inch gas-tight or PVC pipe runs from the gas permeable layer through the house to the roof, to safely vent the radon and other soil gasses above the home.
  5. Junction Box
    In case an electric venting fan is needed later, an electrical junction box is installed.