Radon Mitigation Cost in Colorado

Colorado ranks #5 in the U.S. for radon risk. 83% of Colorado counties are classified by the EPA as Zone 1 — the highest-risk category, with predicted average indoor radon levels above the EPA action level of 4 pCi/L. Here's what that means for mitigation cost.

Colorado radon risk profile

Colorado has 53 of 64 counties (83%) classified as EPA Zone 1. The state's high-altitude geology and uranium-rich Front Range bedrock produce elevated radon across most populated areas, including the Denver metro. Colorado state law (since 2024) requires radon disclosure on residential real estate transactions.

Typical mitigation cost

National typical range: $1,200-$2,500 installed for a standard active sub-slab depressurization (ASD) system in a single-family home. Multi-level or multi-zone homes can reach $3,000-$5,000. These figures are from aggregated contractor pricing surveys and are not specific to Colorado.

We do not publish a Colorado-specific average cost figure because no reliable state-level cost survey is publicly available. Get 2-3 quotes from EPA-listed certified mitigators in your county for accurate Colorado pricing.

Colorado-specific factors

Colorado homes built since 2009 in many counties must be radon-resistant by code (passive radon-resistant new construction). Older homes typically need active mitigation. The Front Range corridor has the highest concentration of mitigation contractors.

How to find a certified mitigator in Colorado

The two main certifying bodies for radon mitigation are the National Radon Proficiency Program (NRPP) and the National Radon Safety Board (NRSB). Both maintain public contractor directories searchable by ZIP code. If you live in a state with a radon program (which Colorado does), the state health department typically maintains a certified-contractor list as well — usually on the department's environmental health page.

Always retest after mitigation. A properly designed system should reduce levels to under 2 pCi/L; verify the result rather than trusting the contractor's word.

Try the calculator

Radon Mitigation Cost Estimator

Get an installed-cost range for a standard ASD system based on home size and foundation type.

Home Inspection Cost Estimator

Pre-purchase home inspection cost — radon testing is often a bundled add-on.

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