Radon
Resistant New Construction
Radon Resistant New Construction means two things:
- Measures are taken to avoid or reduce radon entry and
- Measures are installed to make radon removal easier and less costly if needed.
There are five steps to Radon Resistant New Construction, some of which are probably already included in house plans for other purposes. And the more expensive measures are the ones probably already included. The remaining items may cost less than expected. It makes sense to consider these preliminary techniques during construction. After the home is completed and occupied, it should be tested for radon and removal steps taken only if elevated levels of radon are found.
Checking the site prior to construction will not indicate whether the home will have elevated levels of radon. High or low levels in neighboring homes won't answer the question either. Testing after occupancy is the only way to know, and preliminary measures taken during construction make the solution simpler.
Radon Resistant New Construction is required by some regional codes and by some state or local ordinances.
For drawings and details of suggested radon resistant new construction measures click here.
A. Gas Permeable Layer
This layer is placed beneath the slab or flooring system to allow the
soil gas
to move freely underneath the house. In many cases, the material used is
a 4-inch layer of clean gravel.
B. Plastic Sheeting
Plastic sheeting is placed on top of the gas permeable layer and under the slab
to help prevent the soil gas from entering the home. In crawlspaces, the
sheeting is placed over the crawlspace floor.
C. Sealing and Caulking
All openings in the concrete foundation floor are sealed to reduce soil gas entry
into the home.
D. Vent Pipe
A 3- or 4-inch gas-tight or PVC pipe (commonly used for plumbing) runs from the
gas permeable layer through the house to the roof to safely vent radon and
other soil gases above the house.
E. Junction Box
An electrical junction box is installed in case an electric venting fan is needed
later.