Radon Mitigation Pros in Denver, CO

Finding a qualified radon mitigation contractor in Denver shouldn’t feel like a guessing game, but with Colorado ranking as one of the highest-risk states in the country — and Denver’s Front Range geology practically a radon factory — the stakes of hiring the wrong person are real. This directory cuts through the noise: every contractor listed here holds active NRPP or NRSB certification, so you’re not rolling the dice on a general handyman with a YouTube education.

How to Choose a Radon Mitigation Contractor in Denver

• Verify the credential, not just the claim. Colorado doesn’t license radon contractors at the state level, which means anyone can hang a shingle. Legitimate pros hold NRPP Certified Radon Mitigation Specialist or NRSB Certified Mitigation Professional credentials — both are searchable in public databases. Ask for the certification number and check it.
• Separate the tester from the mitigator. Measurement and mitigation are distinct certifications. If a contractor does both the test and the fix, confirm they hold credentials for each. Some homeowners hire an independent tester to verify post-mitigation results — especially useful in real estate transactions where objectivity matters.
• Ask specifically about sub-slab conditions. Denver’s soils vary dramatically — you’ve got expansive clay in Stapleton, decomposed granite in the foothills, and backfill nightmares in older Capitol Hill basements. A contractor who asks about your foundation type and runs a sub-slab communication test before quoting isn’t being slow; they’re being competent.
• Get the warranty in writing. Standard active soil depressurization systems come with a 1-5 year labor warranty and a fan warranty of 3-5 years depending on manufacturer. If a contractor won’t put that in writing, walk.
• Check for EPA Zone 1 experience. Denver sits squarely in EPA Zone 1 — the highest predicted indoor radon potential. Contractors who’ve worked primarily in lower-risk zones may undersize the mitigation system. Ask how many Zone 1 installs they’ve done in the past year.

Pro Tip: Colorado’s real estate contracts include a radon inspection contingency period. If you’re buying or selling, hire your tester and mitigator separately — it removes any conflict of interest and holds up better if the deal gets contested.

What to Expect

A standalone radon test runs $150–$400 depending on whether you use a passive charcoal canister (mailed to a lab) or an active continuous monitor with a licensed professional overseeing the process. If results come back above 4 pCi/L — the EPA action level — a full active soil depressurization (ASD) installation typically runs $800–$1,500 for a single-suction-point system, with multi-point systems or finished basements pushing toward the higher end. Most installs take 4–8 hours, and post-mitigation testing 24–48 hours later confirms the fix worked.

Reality Check: The contractors who quote $500 for mitigation are cutting corners somewhere — usually on fan sizing, pipe routing, or skipping the post-mitigation test entirely. A cheap system that drops you from 12 pCi/L to 4.2 pCi/L hasn’t actually solved your problem.

Local Market Overview

Denver’s mandatory radon disclosure requirements in real estate transactions keep demand for certified contractors consistently high, and the metro’s ongoing construction boom — particularly in high-radon areas like Aurora, Highlands Ranch, and the Southeast corridor — means new-construction radon-rough-in systems are increasingly standard. Expect a 1–3 week wait for installation scheduling during peak real estate season (April–July); booking your tester early and having a mitigator lined up before results come back saves you the scramble.