The radon test at the home we are buying came back high (6.8). Is it a dealbreaker, and can it be fixed?

A radon result of 6.8 pCi/L is above the EPA action level of 4.0 pCi/L, so it does call for a fix, but it is not a dealbreaker. Radon is one of the most fixable problems a home inspection turns up. An active mitigation system pulls the gas from under the slab and vents it above the roof, and it typically runs $900 to $6,000, and most homes land around $1,950 to $2,250 in New Hampshire. Most buyers keep the deal and either ask the seller to pay for the system or split it at closing.

A high number does not mean the house is bad. It means the soil gives off radon, true of a lot of New England ground. Granite bedrock is common here, and granite is a big radon source, so plenty of fine homes test high. What matters is whether it gets fixed.

What 6.8 actually means

The EPA sets the action level at 4.0 pCi/L. At or above that, they say fix it; between 2.0 and 4.0 they say consider fixing it. Your 6.8 is in the fix-it range. (Source: EPA, epa.gov/radon.) New Hampshire DHHS echoes the same guidance.

Radon is a gas you cannot see or smell. It seeps up through the slab, the floor wall joint, and any crack or gap in the foundation. The fix does not seal those one by one. It changes the pressure under the house so the gas is drawn away before it enters.

How a mitigation system works

The common fix is active sub-slab depressurization. We cut a small hole in the slab, run a sealed pipe into the stone or soil beneath it, and put an inline fan on it. The fan creates suction under the whole floor, so radon gets pulled in and vented above the roofline.

If the home has a dirt or fieldstone crawl space instead of a poured slab, we lay a sealed membrane over the dirt and depressurize under it. Same idea, different floor, and we install both. Our radon guy is Branden, who the crew calls B-Radon, and we hold the state radon cert (RMS-113966).

The system runs quiet and runs all the time. A little gauge tells you the fan is pulling. That is it, no maintenance.

Is it a dealbreaker in the sale?

No. A 6.8 is a normal thing to negotiate, not a reason to walk. Radon comes up in home sales here all the time, and you have a few clean paths: ask the seller to install a system before closing, ask for a credit so you install it after, or split the cost. A mitigation system in NH runs about $900 to $6,000, and most homes land around $1,950 to $2,250, small next to the price of the house. The deal holds.

A finished system protects the home for good and adds a feature the next buyer wants.

What drives the cost

Most homes need one fan and one pipe run, which is the $900 to $6,000, and most homes land around $1,950 to $2,250 range. A few things push it up: a long or awkward pipe route to the roof, a dirt crawl that needs a membrane, or more than one foundation zone, like an addition on its own slab. We inspect free and quote within 24 hours, so you are not guessing during a tight closing.

If you want a fresh test before you commit, a radon test runs $50, credited toward the job if you move ahead. You do not need it for the buy decision, since you already have a number high enough to act on.

What you actually need here

A 6.8 is a standard active system, nothing exotic. If a contractor tries to sell you a giant package for one radon reading, slow down. The job is a pipe, a fan, and a clean vent. If your basement is also wet or the foundation has cracks, those are separate issues with their own fixes, and we will tell you which apply.

Our radon mitigation carries a 10-year warranty. We do not promise a specific post-install number unless we put it in writing, because soil and weather vary. We promise a properly built, sealed, vented system that does its job.

Get a straight quote before you close

Call us at 603-610-1770 or book your free inspection. We will look at the foundation, tell you exactly what your home needs, and quote within 24 hours so radon does not stall your closing.

Helpful pages: radon mitigation, basement waterproofing, crawl space services, structural and foundation repair, and the 603 guarantee.

Outside reading: EPA radon guidance, NH DHHS radon program, and the Insurance Information Institute (iii.org) on home-buying issues.

Related questions

Does a high radon reading lower the home’s value? Not in any lasting way. Once a system is installed, the home is on equal footing with any other. A mitigated home can even appeal to the next buyer, since the work is already done and warrantied.

Who pays for radon mitigation, buyer or seller? It is negotiable. Buyers commonly ask the seller to install a system or give a closing credit toward one. A system runs about $900 to $6,000, and most homes land around $1,950 to $2,250 in NH, so it rarely breaks a deal.

How fast can a system go in before closing? Most single-zone homes are a one-day install once scheduled. We do a free inspection, quote within 24 hours, and work with your timeline so the closing date holds.

Will the system make my basement radon level safe to finish later? A working mitigation system keeps the radon pulled out, which is the foundation for any later finishing. If you do finish the space down the road, we will check that the system still covers the new layout.