Do New Homes in Ohio Need Radon Mitigation?
Why radon matters in Ohio, and why a passive system during construction is the cheap answer.
Radon is a genuine consideration in Ohio, and the practical answer for a new build is to install a passive radon system during construction. It costs a fraction of retrofitting one later, and it can be activated with a fan if testing shows you need it.
What radon is
Radon is a naturally occurring radioactive gas produced by the breakdown of uranium in soil and rock. It enters homes through the foundation, and because it's colorless and odorless the only way to know your level is to test. The EPA identifies radon as a leading cause of lung cancer among non-smokers.
Why Ohio
Ohio's geology produces radon in many areas, and levels vary substantially from one property to the next, sometimes between neighboring houses. Because our homes are relatively tight and heated for a long season, indoor concentrations can build. There's no way to predict your level from your neighbor's, which is why testing rather than assuming is the rule.
Radon-resistant new construction
Building the system in during construction is dramatically cheaper than adding it afterward. A passive system typically includes:
- A gas-permeable layer of aggregate beneath the slab, which you're placing anyway
- A sealed vapor barrier over that layer
- Sealing and caulking of foundation joints, penetrations and the sump lid
- A vent pipe running from beneath the slab up through the house and out the roof
- An electrical junction box in the attic, so a fan can be added later without opening walls
Most of that is either already happening or nearly free while the slab is open. The vent pipe routing is the part that must be planned early, because running it through the house later means opening finished walls.
Testing
Test after you move in, ideally during a heating season with the house closed up normally, since that's when levels are highest. Test the lowest livable level. If results come back elevated, a fan is added to the existing passive stack, which turns it into an active system. That's a small job when the pipe already exists.
What to ask us
Whether a passive system is included as standard or offered as an option on your plan, and how the vent stack will be routed. This is worth settling during design rather than at framing. See our process and basement decisions.
General information only. For current guidance and testing resources, see the Ohio Department of Health's radon program and the U.S. EPA.