What should you do if you find radon in your home?

If your radon test reads 4.0 pCi/L or higher, the EPA says to fix it with a mitigation system, and the most common fix is active sub-slab depressurization that pulls the gas out from under your slab and vents it above the roof. Radon mitigation runs $900 to $6,000, and most homes land around $1,950 to $2,250. If your number lands between 2.0 and 4.0 pCi/L, the EPA says to consider fixing it. Below 2.0, you are fine for now.

Radon is a gas. You cannot see it or smell it. It seeps up through the soil and into the lowest level of your house, usually the basement or crawl space. The number on your test tells you how much is in the air you breathe down there. The EPA action level is 4.0 pCi/L. That is the line.

So you got a number. Here is what to do.

First, do not panic. A high reading is common in New England. Our granite-heavy ground gives off radon all over New Hampshire, Maine, and Massachusetts. A high number does not mean your house is broken. It means the gas has a path in, and that path can be closed.

Second, confirm the level. One short test can swing. If you used a quick charcoal kit, a longer-term test or a follow-up gives you a steadier read before you spend money. NH DHHS keeps guidance on testing and certified pros. We can run a test too. A radon test with us is $50, credited toward the job if you move ahead.

Third, get it mitigated. This is the real fix. A mitigation system is mostly a sealed pipe and a quiet fan. The fan creates suction under your slab. The gas gets pulled up the pipe and out above your roofline before it ever reaches your lungs. On a poured slab, that is sub-slab depressurization. If you have a dirt or fieldstone crawl space, the fix is sub-membrane depressurization, where we lay a sealed membrane over the dirt and pull the gas out from under it. We install both.

What drives the cost? Mostly the layout. A simple basement with one slab and an easy run for the pipe sits at the lower end. A house with multiple slabs, an addition, or a crawl space needs more pipe, sometimes a second suction point, and more labor. That is why we look first and quote second. Radon mitigation is $900 to $6,000, and most homes land around $1,950 to $2,250, and we put the number in writing after we see the space.

Here is the part worth knowing. You may not need anything fancy. If your number is borderline, sealing some cracks and adding airflow can help while you decide. But if you are over 4.0, a fan-driven system is the fix that actually holds. We have seen homeowners chase fixes that do not move the number. A real mitigation system moves it.

Branden runs our radon work. The crew calls him B-Radon. He is certified, and our state radon cert is RMS-113966. We are OSHA-certified, licensed, and insured. Our radon mitigation carries a 10-year warranty. We do not guarantee a specific radon level unless it is written into your agreement, because the gas load in the ground is out of our hands. The system is what we stand behind.

One more thing. After the system is in, you retest to confirm the drop. That retest is your job, not ours, and any certified tester can do it. We point you to it so you are not guessing.

If radon turns up while you are already dealing with a wet basement or a damp crawl, it often makes sense to handle both at once. A wet space and a radon path frequently share the same opening in the floor. See our basement waterproofing and crawl space services pages. The mitigation details live on our radon mitigation page, and what we promise on every job is on the 603 guarantee page.

Found radon? Call us at 603-610-1770 or book your free inspection. We will look at your space, talk you through your number, and give you a written quote within 24 hours. Free inspection, free estimate, no pressure.

Related questions

What radon level is dangerous? The EPA sets the action level at 4.0 pCi/L. At or above that, fix it. Between 2.0 and 4.0, the EPA says consider fixing it. Below 2.0, you are good for now. See epa.gov/radon.

Does radon mitigation work in a dirt crawl space? Yes. We use sub-membrane depressurization. We lay a sealed membrane over the dirt and pull the gas out from under it with a fan, the same idea as a slab system. See our crawl space services page.

How much does radon mitigation cost? Radon mitigation is $900 to $6,000, and most homes land around $1,950 to $2,250, and a radon test with us is $50, credited toward the job if you move ahead. The final number depends on your layout, so we quote after we see the space. Book your free inspection.

Is radon worse in New Hampshire? Our granite-rich ground gives off radon across NH, ME, and MA, so high readings are common here. That is why testing matters. NH DHHS keeps state radon guidance.