What Radon Mitigation Costs in New Hampshire, and What Drives the Price
If a radon test in your home came back at or above 4 picocuries per liter (pCi/L), the level at which the U.S. Environmental Protection Agency recommends fixing a home, the next question is almost always the same: what is this going to cost?
The short answer: most New Hampshire homes with a basement fall into a predictable range, and a handful of things about your house move the price up or down. Here's what we see on jobs across southern, central and coastal New Hampshire, what a good quote should include, and what to expect once the system is running.
What Most New Hampshire Homeowners Pay
For a typical single-family home with a poured or block basement, a professionally installed radon mitigation system from Advanced Radon Mitigation usually costs $1,395 to $2,995, with more complex homes, such as historic foundations and multi-slab layouts, running toward the top of that range or above. Every quote is a flat-rate price for the complete system: certified installation, diagnostics, the fan, piping, sealing, a pressure gauge and a follow-up test to confirm the result.
The only way to get a firm number for your home is an on-site assessment. The sections below explain what we look at when we price a job, so the number on your quote makes sense.
What Changes the Price
Almost every system we install uses the method the EPA recommends for homes with a slab or basement: sub-slab depressurization, also called active soil depressurization. A pipe is placed through the basement floor, and a small fan pulls radon from the soil beneath the house and vents it above the roofline before it can enter your living space. The equipment is similar from house to house. What varies is the work needed to install it well.
What's under your basement floor
Gravel or crushed stone under the slab lets air move freely, so one suction point often covers the whole house. Dense soil, clay or ledge, all common with New Hampshire's granite, can limit airflow and may call for a second suction point or a larger fan.
Additions and multiple slabs
Many New Hampshire homes have been added onto over the years: a basement under the original house, a slab-on-grade family room, a garage conversion. Each section can sit on its own slab, and each may need its own suction point tied into the system. Multi-slab work is something we do regularly, and it's one of the most common reasons a job lands toward the upper end of the range. If part of your home is a dirt-floor cellar or crawl space, we'll assess it and advise on the right approach.
Where the pipe can run
The cleanest installations route the pipe through a garage or an interior closet up to the attic. When that isn't possible, the pipe runs up the outside of the house. Long runs, finished spaces and roofline details all affect the labor involved.
Sump pits, cracks and openings
An open sump pit is one of the easiest ways for radon to get in, so it needs an airtight cover. Large foundation cracks and gaps around pipes are sealed as part of the job.
Electrical work
The fan runs around the clock and needs a dedicated, outdoor-rated electrical connection. If there's no convenient circuit nearby, electrical work adds to the cost.
Finished basements
Carpet, framing and drywall don't prevent mitigation, but they can make the work take longer and limit where the pipe can go.
Radon in Water Is a Separate System
Many New Hampshire homes on private wells also have radon in their water. When you run a shower or a dishwasher, some of that radon is released into the air you breathe. Treating radon in water uses a different system, usually aeration, which starts at around $6,500 and is priced separately from air mitigation. If you're on a well, it's worth having both checked. Our Water Treatments page explains the options.
What a Good Radon Mitigation Quote Includes
When you compare quotes, check that each one includes:
- A contractor certified by the National Radon Proficiency Program (NRPP). Ask for proof of certification.
- Diagnostics done with a real radon fan during installation. The fan sized for your soil type is run under the slab to measure actual airflow. A shop vacuum pulls far more suction than a radon fan and can overstate how well a system will perform.
- The fan, piping, sealing of the sump and major cracks, and a labeled system
- A manometer (pressure gauge) so you can see at a glance that the fan is working
- A post-mitigation radon test, analyzed by an independent lab, to confirm the level has come down
- A written warranty on the installation and the fan
A low price that leaves out the follow-up test, or that comes from an uncertified installer, can cost more in the long run.
Who Pays When a Home Is Being Sold
In a home sale, radon is often handled through the inspection contingency. Sometimes the seller installs a system before closing, sometimes the price is adjusted, and sometimes the buyer takes it on after closing. It depends on what the buyer and seller negotiate. Our guide to radon testing and mitigation during an NH home sale walks through the options for buyers, sellers and agents. We prioritize real-estate transactions, but installations could sometimes be a couple of weeks out. If you’re selling, or thinking about selling, test as soon as possible to avoid any delay in closing.
What It Costs to Run a Radon System
Once installed, a mitigation system is inexpensive to live with. The fan draws a small, steady amount of electricity. Fans do wear out eventually, and a replacement is a much smaller job than the original installation. The EPA recommends retesting your home every two years, and after any major renovation, to make sure the level stays low.
Is Radon Mitigation Worth the Cost?
The EPA identifies radon as the leading cause of lung cancer among non-smokers and the second leading cause overall. A properly installed system is designed to keep levels low for many years, and it's the fix the EPA recommends when a home tests at or above 4 pCi/L. For most families it's a one-time project with a clear result you can measure with a follow-up test.
Frequently Asked Questions
How much does radon mitigation cost in New Hampshire?
Most single-family homes with a basement fall between $1,395 and $2,995. Historic foundations and multi-slab homes typically land toward the upper end or above. Soil under the slab, pipe routing and electrical work also move the price.
How long does installation take?
Most radon air systems are installed in a single day. Historic-home and multi-slab installs occasionally need a second visit. Scheduling timelines can vary, so if you’re working toward a closing date, call as early as you can.
Does radon mitigation actually work?
Sub-slab depressurization is the method the EPA recommends, and a post-mitigation test confirms the result in your home. That's why a follow-up test should always be part of the quote.
Can I lower radon myself?
Sealing cracks helps, but the EPA notes that sealing alone hasn't been shown to lower radon significantly or consistently. A fan-driven system installed by a certified professional is the reliable fix.
Do you also treat radon in well water?
Yes. Radon in water is treated with a separate system, usually aeration for high levels or carbon filtration for moderate levels. We collect a water sample for a state-accredited lab to analyze before recommending a system.
Get an On-Site Estimate
Advanced Radon Mitigation & Water Treatment is a New Hampshire-only contractor with more than 25 years of experience and AARST/NRPP-certified technicians on every job.
Call 603-644-1207. Talk directly to a certified technician.
Request a quote: use the form at /contact/. We respond within one business day.