New Construction Radon-Resistant Systems in Idaho Falls, ID

The cheapest and easiest time to handle radon is before the home is finished. Radon-resistant new construction (RRNC) builds the key protective components into the structure during the build, so the home is protected from day one, and if an active mitigation system is ever needed later, the pipe rough-in is already there.

For builders and homeowners planning new homes in Idaho Falls, Ammon, and the growing subdivisions expanding across Bonneville County, this is genuinely good practice. The Snake River Plain's geology means every new home site here has elevated radon potential. Building radon-ready is inexpensive during construction and expensive to retrofit later.

A passive radon-resistant system installed during construction includes several coordinated components. A gas-permeable layer of clean aggregate or a permeable mat is placed beneath the slab before the concrete pour. A polyethylene vapor barrier goes over the aggregate, sealed at all penetrations and edges. All foundation openings, plumbing penetrations, sump pit lids, expansion joints, are sealed. A 3- or 4-inch PVC vent pipe is run from the sub-slab area up through the interior of the home and exits above the roofline. The system relies on natural airflow, the stack effect of warm air rising through the vent pipe, to move radon out of the sub-slab area continuously. In many homes, a well-designed passive system reduces indoor radon levels enough on its own that no fan is ever needed.

Once the home is finished and lived in for a season, a radon test tells you whether the passive system alone is sufficient. If levels stay below 4.0 pCi/L, no further action is needed, the passive system is doing its job. If levels come back at or above 4.0, activating the system is quick and inexpensive: an inline radon fan is added to the existing vent pipe, typically in the attic where the pipe passes through. This turns the passive system into an active one without any retrofitting of the foundation. The whole activation is usually a half-day job and costs a few hundred dollars rather than the $1,000 to $2,000 a full retrofit mitigation would cost on a finished home.

Idaho Falls sits in one of the higher-radon regions in the country. Every new home built in Bonneville County is being built on soil that produces radon. Building radon-ready during construction adds a modest cost to the overall build, typically a few hundred to just over a thousand dollars for a single-family home, while a full retrofit mitigation later can cost $1,500 to $3,000+ and involves cutting into a finished foundation. For custom-home builders and buyers of new construction in Idaho Falls-area subdivisions, radon-ready construction is also a resale advantage. Health-conscious buyers increasingly ask about radon during purchase, and a home built with a passive system rough-in is easier to test, mitigate, and market than an older home with no radon planning.