ResourcesGlossary: fixing
Radon-resistant new construction
Short answer
Radon-resistant new construction, RRNC for short, is a set of features built into a new home to keep radon out and to make a later fix simple: a gas-permeable layer under the slab, plastic sheeting, sealing and caulking, a vent pipe, and a junction box for a fan.
What radon-resistant new construction means
EPA says more than 1.5 million new homes have been constructed since 1990 with radon-resistant features, and recommends building new homes with them in high radon potential areas, which its map calls
The pipe on its own is a passive system. EPA's builder guide says such a system effectively reduces radon levels by an average of about 50 percent.
The builder's dimensions, in metric
EPA gives the sizes in inches. Each row converts one to centimeters.
| Feature | EPA's size | In centimeters |
|---|---|---|
| Layer of clean, coarse gravel under the slab | 4 inches | 10.2 |
| Vent pipe, the smaller size | 3 inches | 7.6 |
| Vent pipe, the size EPA's builder guide prefers | 4 inches | 10.2 |
What it means for your home
Built-in features are a head start, not a test result. EPA says every new home should be tested for radon as soon as possible after occupancy, even if it was built to be radon-resistant.
If you are buying or renting a new home, EPA's advice is to ask the owner or builder if it has radon-resistant features.
Where to go next
- Radon fan running cost calculator. See what a fan would cost to run if the passive pipe needs one.
- Radon-resistant new construction: the features and the codes. What builders install, what it costs and which states require it.