What should I know about radon when buying a home in Colorado Springs?

Radon is common in Colorado Springs homes, but it's usually straightforward to fix. Radon is a naturally occurring radioactive gas from the soil that you can't see or smell, and it's a leading cause of lung cancer in nonsmokers. I recommend a radon test during your inspection period on every home. If it comes back high, you can ask the seller to install a mitigation system or give a credit. If the seller says no and you still want the home, know the likely cost to install one yourself.

Why radon matters here

Radon comes from uranium in the soil and rock, and Colorado's geology produces a lot of it. El Paso County Public Health reports that more than 40% of homes tested in the county between 2005 and 2023 had high radon levels, and the county is in EPA's highest-potential zone. The Colorado Department of Public Health and Environment estimates about 500 radon-related lung cancer deaths a year in Colorado.

Two homes on the same street can test very differently, so a neighbor's result doesn't tell you much about the house you're buying. The only way to know is to test.

How testing works

• During a purchase, a radon test is usually done alongside the general home inspection, within your inspection period. A short-term test typically runs a couple of days under closed-house conditions.
• The number to watch is 4 picocuries per liter (pCi/L), EPA's action level. EPA also suggests considering mitigation between 2 and 4 pCi/L, since there's no known safe level.
• If you already own the home, El Paso County Public Health's lab on West Garden of the Gods Road sells short-term test kits for about $15 (as of October 2026), and longer-term kits give a better picture of year-round levels.

What Colorado sellers must disclose

Colorado law requires every residential purchase contract to include a radon warning recommending that all buyers test. The seller must also disclose whether any radon tests have been done, provide the most recent results and records, disclose any mitigation, say whether a mitigation system is installed, and give the buyer the state's radon brochure. What disclosures Colorado sellers need to think about covers the rest of the disclosure form.

If the home already has a system, ask when it was last tested. El Paso County recommends retesting homes with existing systems every few years to make sure the system is still working.

How a radon system works

Mitigation is fairly straightforward. It's all about moving air. The most common system uses a vent pipe and a fan that pulls radon from the soil beneath the home, or from a crawl space or basement area, and discharges it above the roof, away from windows and doors. Depending on the age of the home, an existing perimeter drain can sometimes be part of the design.

El Paso County Public Health says these systems can reduce radon levels by up to 99%. Use a certified radon mitigation contractor; the Colorado Radon Office and CDPHE list certified professionals. After installation, a follow-up test confirms the system is working.

What it costs

Right now, in my experience, a typical system runs about $1,300 to $2,000 (as of October 2026), though it depends on the layout of the home. El Paso County Public Health cites about $1,000 to $2,000 for a typical Colorado system. A home with a crawl space, a finished basement, or an unusual layout can cost more.

New homes can be built with radon-resistant features, which is usually less expensive than adding a system later. If you're buying new construction, ask the builder what's included.

How it gets handled in a purchase

Under Colorado's standard contract, a high radon result is something you can raise in your inspection objection before the deadline. Both common approaches work:

• The seller installs a system before closing, with a follow-up test showing the result.
• The seller gives a credit or lowers the price, and you install the system after closing. How seller concessions work explains what a lender allows.

As a buyer, I'd ask for one of those. But it all depends on the market. What matters most is this: if the seller says no and you know you want the home, what's the expected cost to install a system yourself? If that number works for you, a "no" doesn't have to end the deal. What contingencies to consider covers the inspection deadlines.

Help paying for mitigation

CDPHE runs a Low Income Radon Mitigation Assistance Program that helps qualifying Colorado homeowners pay for a system. Check the program's current eligibility rules before you apply.

What could change the answer

• The test result, and whether it's above 4 pCi/L or between 2 and 4.
• The home's layout: crawl space, finished basement, or slab.
• Whether a system is already installed and when it was last tested.
• How competitive the market is, which affects whether a seller will install or credit.
• New construction with radon-resistant features already built in.

When to talk with a professional

Use a certified radon tester and a certified mitigation contractor; the Colorado Radon Office can point you to them. For health questions about radon exposure, talk with your doctor. Your real estate agent can help you raise a result within the contract deadlines and negotiate the outcome.

Sources

• El Paso County Public Health, Radon: https://elpasocountyhealth.org/services/radon
• El Paso County, National Radon Month news release (January 2026): https://epc-assets.elpasoco.com/wp-content/uploads/sites/18/2026/01/News-Release-National-Radon-Month-Accessibility-Checked-1.13.pdf
• C.R.S. § 38-35.7-112, radon disclosure in residential real estate transactions: https://colorado.public.law/statutes/crs_38-35.7-112
• U.S. Environmental Protection Agency, What is EPA's action level for radon and what does it mean?: https://www.epa.gov/radon/what-epas-action-level-radon-and-what-does-it-mean
• Colorado Division of Real Estate, Contract to Buy and Sell Real Estate (Residential), CBS1: https://dre.colorado.gov/real-estate-broker-contracts-and-forms