Radon mitigation in the Helena Valley
Radon testing and systems for the unincorporated neighborhoods spread across the valley floor north and east of Helena.
A large share of the Helena area lives outside city limits, in census-designated places named for their part of the valley. Helena Valley Southeast, along Canyon Ferry Road between Helena and East Helena, had 9,168 residents in 2020. Helena Valley West Central, just north of the city with Interstate 15 on its east side and the Scratchgravel Hills to the west, had 8,670. Helena Valley Northeast lies to the north of the southeast section, and other parts of the valley fill in around them.
Does building on the valley floor change radon risk?
There's no rule you can apply from a map. Radon depends on the soil and fill directly under each house and on how tightly the foundation is sealed. Two houses on the same valley road can test very differently, so each one needs its own test.
Private wells and radon
If your valley home is on a private well, keep in mind that Montana DEQ notes that radon in well water is released into the air when you shower, wash dishes or cook, adding roughly 1 pCi/L to indoor air for every 10,000 pCi/L in the water. Test the air first, since that's where most exposure comes from, and ask a certified lab about testing your well water too. DEQ lists aeration and granular activated carbon as treatment options.
Typical radon jobs in the valley
- Sub-slab systems in newer houses with full basements
- Activating a passive radon pipe in a newer build by adding a fan
- Exterior pipe runs designed for open, windy lots and cold nights
- Testing for buyers and sellers in new subdivisions
Common questions
Do radon companies come out to the valley?
Yes. The companies we work with serve the Helena Valley. Call with your address and we'll connect you.
My new house has a radon pipe. Is that enough?
Not always. A passive pipe without a fan may not bring levels low enough, which is why DEQ recommends testing a new home in its first year.
Services in the Helena Valley
- Radon testingShort-term and long-term tests, continuous monitors, confirming a high kit result and post-mitigation checks.
- Radon mitigation systemsSub-slab depressurization: a sealed suction point, a radon fan and a pipe that vents soil gas above the roof.
- Crawl space and mixed foundationsSealed-membrane systems for dirt crawl spaces, plus slab sections, additions and older stone or brick foundations.
- Radon for buyers and sellersTesting inside the inspection window, handling a high result before closing, and checking an existing system.
- Radon fan replacement and repairQuiet or noisy fans, level manometers, iced or damaged pipe, system alarms and retesting older systems.
Nearby areas
Radon result came back over 4 pCi/L?
Call and get connected with a Helena-area radon company that can look at your foundation and design a system.