Radon Mitigation Companies Near Me: How to Choose
Colorado sits on uranium-rich geology that pushes radon levels well above the national average, so a search for “radon mitigation companies near me” is one many Front Range homeowners run after a test comes back at or above the EPA action level of 4 picocuries per liter (pCi/L). Choosing the right contractor matters because a mitigation system is a permanent fixture that should reliably lower radon for decades. This guide summarizes EPA and Colorado guidance current as of 2026 and is informational only — it is not a substitute for a certified radon professional, and anyone concerned about radon’s health effects should consult their physician. Below is a structured way to verify credentials, compare bids, and avoid the common mistakes that lead to underperforming systems.
How do you choose a radon mitigation company near you?
Lead with certification. A qualified radon mitigation contractor should hold a national certification through the National Radon Proficiency Program (NRPP) or the National Radon Safety Board (NRSB). These programs require training, exams, and continuing education, and they are the clearest signal that a company knows the building science behind sub-slab depressurization. After certification, compare each company on system design, warranty, post-mitigation testing, and price — in that order, with price last rather than first.
Colorado is a high-radon state, which means there is steady demand and, unfortunately, some operators who cut corners. Verifying credentials and getting multiple detailed bids separates the careful firms from the rest. The full framework for understanding radon and your options lives in our radon testing guide for Front Range homeowners, which is worth reading before you start collecting quotes.
Verify certification and insurance
Ask every company for its NRPP or NRSB certification number and verify it through the certifying body’s online directory. Certification means the installer was trained in proper diagnostics, fan sizing, and sealing — the difference between a system that hits below 2 pCi/L and one that barely moves the needle. Colorado does not run its own contractor license for radon mitigation, so national certification is the main competency credential available to homeowners here.
Insurance is the second checkpoint. A reputable company carries general liability coverage, and you should confirm it before any drilling begins. Mitigation involves cutting into the slab and routing pipe and electrical work, so an uninsured contractor leaves you exposed if something goes wrong. A professional firm provides certification and insurance details without resistance. If a company dodges these questions, move on.
Experience with Front Range homes
Ask how many systems the company installs each year and whether it has worked on homes like yours — a finished basement, a crawl space, a slab-on-grade, or a home with multiple foundation types. Front Range housing includes all of these, and each calls for a different mitigation approach. A company that installs systems weekly across Douglas, Jefferson, and El Paso counties has seen the local soil and construction patterns that drive radon entry. Experience with your specific foundation type is more telling than years in business alone.
Understand how mitigation works before you compare bids
The most common and effective method is active sub-slab depressurization (ASD). The installer cuts a hole in the foundation slab, inserts a pipe into the soil or gravel beneath, and connects an in-line fan that draws radon-laden air from under the home and vents it above the roofline. Done correctly, ASD reverses the pressure that pulls radon indoors and typically drops levels well below the action threshold. Knowing this baseline lets you judge whether a bid’s design makes sense. Our explainer on how to get rid of radon covers the method in plain language.
Good design accounts for the home’s specifics: the suction point location, the fan size matched to the sub-slab conditions, sealing of slab cracks and the sump pit, and a manometer (a simple pressure gauge) so you can confirm the fan is running. A bid that ignores sealing, places the suction point poorly, or specifies an undersized fan will underperform. Crawl spaces usually require a sealed vapor barrier connected to the suction system rather than slab penetration, so confirm the contractor proposes the right approach for your foundation.
How to compare radon mitigation bids
Collect at least three written bids and read them for substance, not just the bottom line. A complete bid specifies the method (ASD, sub-membrane for crawl spaces, etc.), the suction point location, the fan model and size, the routing of the vent pipe (interior through the roof versus exterior up the wall), sealing work included, the manometer, and post-installation testing. It should also state the guaranteed result — reputable companies guarantee they will bring radon below 4 pCi/L, and the best aim well below 2 pCi/L.
Watch for what bids leave out. A low quote that omits post-mitigation testing, skips sealing, or routes pipe in a way that fails local code is not a bargain. Ask each company the same questions and tabulate the answers so you can compare equivalent scopes. Pricing context is detailed in our cost of radon mitigation guide, which helps you spot bids that are suspiciously low or high.
What radon mitigation costs on the Front Range
A typical residential ASD system in the Denver metro and along the Front Range commonly runs $1,200 to $2,500, with most homes landing in the middle of that range. Price varies with foundation type, the number of suction points needed, the difficulty of routing the vent pipe, and whether the system is interior (cleaner appearance, often pricier) or exterior. Homes with multiple foundation sections or finished basements that complicate pipe routing cost more because the labor and design effort increase.
Treat an unusually cheap bid with caution. A $700 system that skips diagnostics and sealing may fail to lower radon adequately, forcing a second contractor to redo it. The cost-effective choice is a properly designed system that works the first time and comes with a guarantee and post-installation test confirming the result.
Warranties, fans, and post-mitigation testing
Two warranty elements matter. First, the workmanship and performance guarantee: the company should guarantee that radon will be reduced below the EPA action level, in writing, and commit to adjusting the system at no charge if a post-installation test shows it did not. Second, the fan warranty: radon fans are the moving part most likely to fail, and quality fans carry manufacturer warranties of around five years. Ask what the company charges to replace a fan after the warranty lapses.
Post-mitigation testing is non-negotiable. The only way to know the system works is to test radon again after installation, typically after the system has run for at least 24 hours. A professional company includes this test or arranges an independent one. Do not accept “the system is running, so you’re fine” — a running fan is not proof of a low radon level. The manometer confirms airflow; only a follow-up radon test confirms the result.
Red flags when hiring a mitigation company
Several signs should give you pause. A company without NRPP or NRSB certification lacks the standard competency credential. One that skips diagnostics — offering a fixed quote sight-unseen for any home — may not be designing for your foundation. A bid that omits sealing, post-mitigation testing, or a written performance guarantee is incomplete. High-pressure sales tactics, or a contractor who also performed your radon test and pushed an immediate install, can signal a conflict of interest worth scrutinizing.
Reviews help, but read them critically. Look for volume and detail over time, and read the negative reviews for patterns — complaints about systems that did not lower radon, unreachable contractors, or sloppy pipe routing matter more than scheduling gripes. Cross-check the company against the certifying body’s directory to confirm the credential is current. For more on what a quality installation entails end to end, see our radon mitigation installation guide.
What questions should you ask before signing?
A short list of pointed questions quickly separates careful companies from the rest. Ask: What is your NRPP or NRSB certification number, and may I verify it? Will you perform a diagnostic visit or pressure-field test before designing the system? How many suction points do you anticipate, and where will they go? Is the vent pipe routed interior or exterior, and where will it discharge relative to windows and the roofline? What fan model do you use, and what is its warranty? Do you include post-mitigation testing? Do you guarantee a result below 4 pCi/L in writing, and what happens if the test comes back high?
The quality of the answers tells you as much as the answers themselves. A professional explains the reasoning — why this suction point, why this fan size — while a less careful operator gives vague or one-size-fits-all responses. Also ask about timeline, whether a permit is required and who pulls it, and how electrical work for the fan is handled. A company that needs an electrician for a dedicated circuit and says so up front is being straight with you; one that hand-waves the wiring may be cutting a corner that matters for safety and code.
Watch the test-and-install conflict
One conflict deserves its own scrutiny: a company that both tested your home for radon and then quoted the mitigation. While many reputable firms do both, the arrangement creates an incentive to report a high reading and sell a system. Protect yourself by using an independent measurement — either a separate testing provider or your own verified test — to confirm the level before committing to mitigation, and always insist on independent or at least documented post-mitigation testing to verify the system worked. Trustworthy companies welcome this verification rather than resisting it.
How to move forward with confidence
Once you have verified certification and insurance, gathered three substantive bids, and confirmed each includes diagnostics, proper design, sealing, a performance guarantee, and post-mitigation testing, you can choose on value rather than on the lowest number. Schedule the work, plan to be home for the diagnostic visit if the contractor offers one, and insist on a follow-up radon test to confirm the result. Keep the documentation — system design, warranty, and the post-installation test — for your records and for resale, since buyers increasingly ask for proof a mitigation system works.
A well-chosen radon mitigation company installs a system you can largely forget about: a quiet fan, a manometer you glance at occasionally, and radon levels held safely low for years. Given Colorado’s elevated radon geology, that peace of mind is worth the diligence of vetting the contractor properly rather than hiring whoever answers first.
What about ongoing service and warranties after installation?
The relationship with a mitigation company does not end at install day, and the better firms make that clear up front. Ask what the workmanship warranty covers and for how long, and whether the company will return to adjust the system at no charge if a post-installation test comes back above the action level. Radon fans are the component most likely to fail over time; quality fans carry manufacturer warranties of roughly five years, and a reputable company will tell you what replacing one costs after that window and whether they offer a service plan.
Responsiveness matters as much as the paper warranty. A company that answers the phone years later when your manometer reads flat or your fan grows noisy is worth more than one that disappears after cashing the check. Before you sign, ask how the company handles service calls, whether it stocks replacement fans, and what its typical response time is. Keep all documentation — the system design, the warranty, the post-installation test — in one place, both for your own reference and for the buyer who will eventually ask for proof the system works when you sell. In a high-radon market, that paperwork is part of the home’s value.
References
- Consumer’s guide to radon reduction — U.S. Environmental Protection Agency
- Radon information and contractor guidance — Colorado Department of Public Health and Environment
- Radon and lung health — American Lung Association
If your Front Range home tested high for radon and you want help connecting with a certified, insured mitigation contractor, reach out through our contact page for a referral to a vetted local professional.