What radon is
Radon is a radioactive gas that forms naturally when uranium in soil and rock breaks down. You cannot see it, smell it, or taste it. Outdoors it disperses harmlessly. Indoors, it can collect until the concentration is high enough that long-term exposure becomes a real health concern — radon is the second leading cause of lung cancer in the United States and the leading cause among non-smokers.
Why Colorado
Much of the Front Range sits on geology that produces radon, and Colorado homes routinely test higher than the national average. That is not a reason to panic; it is a reason to test. Neighboring homes can read very differently, so a neighbor's result tells you nothing reliable about yours.
How it gets inside
- Cracks and joints in concrete slabs and foundation walls
- Sump pits and floor drains
- Gaps around pipes and utility penetrations
- Crawl space soil, when the crawl is not sealed
- Hollow block foundation walls
The mechanism is simple pressure: a house behaves like a chimney, and warm indoor air rising pulls soil gas in through those openings.
What the numbers mean
Radon is measured in picocuries per liter (pCi/L). The EPA action level is 4 pCi/L, and the World Health Organization recommends action at 2.7. There is no known safe level, but 4 is the line at which the EPA recommends fixing a home. Most mitigated homes land well below 2.
Testing
A short-term test runs two to seven days and gives you a solid first answer. Certified 48-hour testing with a continuous monitor is the standard for real estate transactions, because it records hourly data and satisfies documentation requirements. Test in the lowest livable level of the home, with windows closed and the HVAC running normally.
Ready to test? See radon test kits and continuous monitors.
Mitigation
Mitigation is not a filter or a sealant. It is a small, permanent ventilation system that reverses the pressure under your home so soil gas goes out through a pipe above the roof instead of into your living space. It runs continuously, costs very little to operate, and needs almost no maintenance.
Living with a system
- Leave the fan running. It is designed to run continuously.
- Watch the monitor gauge — the liquid levels should show a pressure difference.
- Retest every two years, and after major renovations or foundation work.
- Call us if the fan gets loud, stops, or the gauge reads flat.
Common questions
Can I just open windows and seal cracks?
No. Sealing alone typically does not reduce radon much — the gas still finds a path — and open windows are not a solution in a Colorado winter.
Do mitigation systems hurt resale value?
They help it. A documented, working system with a passing retest is a selling point in this market.
Is a system expensive to run?
A typical fan uses roughly the electricity of a light bulb left on, which is a few dollars a month.
Questions about your own numbers?
Send us your test results and we will tell you plainly whether you need a system.