Radon mitigation in Helena, Montana
Radon testing and systems for houses across Montana's capital, from the historic core to the newer neighborhoods at the edges of town.
Helena had 32,091 residents at the 2020 census and is the seat of Lewis and Clark County as well as the state capital. It began as a gold camp after the 1864 strike in Last Chance Gulch, and the wealth from that era left a stock of Victorian houses and brick and stone buildings, including the tenements of Reeder's Alley built between 1872 and 1884. The city sits at about 4,000 feet, with Mount Helena City Park close by.
Do older Helena houses have more radon?
Not necessarily, but they're often harder to fix. Homes from the 1800s and early 1900s can have stone or rubble foundations, partial dirt-floor cellars and lots of small openings to the soil. A system for one of those may combine a membrane over exposed soil with a suction point through any concrete floor, plus more sealing than a modern basement needs.
Earthquakes and foundation cracks
Helena sits in the northern part of the Intermountain Seismic Belt. In October 1935 a magnitude 6.2 earthquake and a magnitude 6.0 aftershock hit the city, destroying more than 200 chimneys and badly damaging Helena High School. If you notice new cracks in a basement slab or foundation wall after ground shaking, retest; cracks give soil gas a new way in.
Typical radon jobs in town
- Sub-slab systems in ranch and split-level houses with full or partial basements
- Combination systems in older homes with cellars and crawl sections
- Interior pipe routes through garages to keep piping out of the winter cold
- Testing on real estate deadlines
Common questions
Do radon companies cover all of Helena?
Yes. Call with your address and you'll be connected with a company that works in your neighborhood.
Where can I get a test kit in Helena?
Hardware stores carry kits, and Montana DEQ's Radon Control Program has offered discounted mail-in kits. Its hotline is 1-800-546-0483.
Services in Helena
- 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.