Radon Mitigation Cost in Denver

Updated October 2026 · 8 public sources cited

Colorado's health department publishes a price range, and the state will help pay for low-income homeowners. Here's what Denver homeowners should budget and how to keep the bill fair.

Denver price ranges at a glance

*Unless the program approves more in advance. Funds go straight to an eligible certified contractor.³

For comparison, National Radon Program Services, an EPA-funded program at Kansas State University, puts the U.S. average at about $1,200, with a range of about $800 to $2,500.⁴ Colorado's state range starts higher, so don't be surprised if Denver bids come in above the national average.

Why Denver bids differ

• Foundation and barrier. A basement slab works as the barrier. A crawl space needs 6-mil plastic sheeting laid and sealed first, which adds material and labor.¹
• Existing passive pipe. If your builder installed a passive system, activating it with a fan is far cheaper than building new.¹
• How hidden you want it. National Radon Program Services notes that part of the cost depends on concealing the system. An exterior pipe can work well but looks different from one run through an interior closet.⁴
• Size and design of the house, plus which reduction method it needs.⁴

The cost after install

The fan runs around the clock. National Radon Program Services compares its electricity use to a 60–90 watt light bulb left on all the time. Some heated or cooled air gets pulled out too, which good sealing can minimize. Fan warranties are typically 5 years, and fans usually last 10 to 15 years.⁴

Colorado's Low Income Radon Mitigation Assistance (LIRMA)

CDPHE runs a program to help low-income homeowners pay for mitigation.⁵ Under the program rules:³¹

• You must own the home and live in it as your primary residence.
• Household adjusted gross income must be under the county limit for your household size.
• You need a radon result over 4 pCi/L from within the past year, from a certified test device.
• Assistance is capped at $1,500 unless approved in advance, and it's paid directly to an eligible certified contractor.
• You can apply once per calendar year.

CDPHE says it mitigated more than 200 homes through the program in 2025.⁶ Denver's health department describes it as paying up to 100% of the cost for eligible households, so check the current rules with CDPHE before you sign a contract.⁷

Buying a Denver home with high radon

Under SB23-206, Colorado residential sales contracts must include a radon disclosure in bold type.⁸ CDPHE encourages buyers to test during the inspection with a licensed measurement professional using a continuous radon monitor. If levels are high, CDPHE says to work with the seller to get a system installed.² A written bid from a licensed Colorado mitigator gives you a concrete number for that negotiation.

General information summarized from the public sources listed below. It isn't professional, medical or legal advice. A licensed professional who inspects your home can tell you what it needs.