Common questions about radon
- Can asbestos block radon that’s outside? It is in my basement floor
- Can radon levels of 100 be mitigated effectively, and if so how much?
- Did you have radon mitigation done in your home? What things should you know first?
- Do ceiling fans reduce radon?
- Do radon mitigation systems decrease the value of your house?
- Does it matter if I test for radon in the summer or the winter
Exeter radon mitigation — local context
Radon is a real concern in Exeter. The NH Department of Health and Human Services (Aug 2023 data brief) found that half of all tested homes in Exeter's Rockingham County measured 7.9 pCi/L or higher — nearly double the EPA 4.0 action level — making it one of the three NH counties with the most elevated-radon homes. The EPA's Map of Radon Zones places Rockingham in Zone 2 (moderate, 2–4 pCi/L predicted). Exeter was settled in 1638 at the falls where the Exeter River meets the tidal Squamscott River, so much of the town center is colonial-era housing with fieldstone foundations and dirt crawl spaces — exactly the harder radon-entry cases we specialize in. The USGS notes NH's granite bedrock and the private wells drilled into it (≈40% of residents) drive that risk. For dirt crawl spaces we install sub-membrane depressurization. Our radon mitigation runs $900–$6,000 (most jobs $1,950–$2,250); a radon test is $50, credited toward the job if you proceed. Cert RMS-113966.
What a recent customer said
Most importantly, our radon level dropped within 24 hours from 11.3 pCi/L to 0.48 pCi/L!
Frequently asked questions
How high are radon levels around Exeter, NH?
Exeter is in Rockingham County, where NH DHHS (August 2023) found half of all tested homes measured 7.9 pCi/L or higher — nearly double the EPA 4.0 pCi/L action level. The EPA's Map of Radon Zones rates Rockingham as Zone 2 (moderate, 2–4 pCi/L predicted). The only way to know your home's level is to test it.
Why are Exeter's older homes harder to mitigate for radon?
Exeter was settled in 1638 along the Exeter River and tidal Squamscott River, so its core housing stock is colonial-era — often built on fieldstone or rubble foundations with dirt crawl spaces. Those are the harder radon-entry cases. In a dirt crawl space we install sub-membrane depressurization to seal and vent the soil gas, which is our specialty in old and historic New England homes.
Where does the radon in Exeter homes come from?
Per the USGS, radon in New Hampshire comes from uranium breaking down in the state's granite bedrock and the private wells drilled into it — about 40% of NH residents rely on private wells. That granite-and-well geology underlies Exeter's river-valley setting, which is why testing matters here even though Rockingham is rated EPA Zone 2 rather than Zone 1.
Radon Mitigation in nearby New England towns
More 603 services in Exeter
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- Crawl Space Encapsulation in Exeter, NH
- Foundation Crack Repair in Exeter, NH