When buyers picture Crested Butte, they think of clean mountain air, open skies, and stunning views. What most people do not think about is radon. But if you are buying a home in Crested Butte, Gunnison, or anywhere in Gunnison County, radon testing is one of the most important steps you can take before closing. Here is what you need to know.
What Is Radon?
Radon is a naturally occurring radioactive gas that forms when uranium in soil and rock breaks down. It seeps up through the ground and into buildings through foundation cracks, gaps around pipes, and other entry points. Once inside, it can accumulate to dangerous levels, especially in lower levels of a home where ventilation is limited.
You cannot see radon, smell it, or taste it. The only way to know if it is present at harmful levels is to test for it.
Why Crested Butte Is a High-Risk Area
The entire state of Colorado is classified as EPA Zone 1, meaning it has the highest potential for elevated indoor radon levels. The average indoor radon level in Colorado is 6.3 picocuries per liter (pCi/L), which is more than double the national average and more than twice the EPA's action level of 4 pCi/L.
Gunnison County's geology, with its granite bedrock and glacially carved terrain, contributes to naturally higher uranium concentrations in the soil. High-altitude communities like Crested Butte sit on terrain that can channel radon directly into building foundations. That means even well-built, modern homes can test above the action level.
How Radon Enters Your Home
Radon follows the path of least resistance. In mountain homes, common entry points include cracks in concrete slabs and foundation walls, gaps around utility pipes and wiring, crawl space floors and walls, and construction joints. Older homes with stone foundations or unfinished basements are particularly vulnerable, but slab-on-grade construction is not immune.
Homes with basements or lower levels used as living space are at higher risk simply because those areas are closer to the source and often have less airflow.
The Health Risk Is Real
Radon is the second leading cause of lung cancer in the United States, responsible for approximately 21,000 deaths per year according to the EPA. For non-smokers, it is the leading environmental cause of lung cancer. The risk increases with both the concentration of radon and the length of exposure, which is why buyers who plan to spend significant time in a home need to take this seriously.
The good news is that the risk is entirely preventable with proper testing and mitigation.
What Radon Testing Looks Like
A professional radon test typically involves placing a continuous electronic monitor in the lowest livable area of the home for 48 hours. The monitor measures radon levels over time and produces a detailed report. Results above 4 pCi/L trigger a recommendation for mitigation.
Testing during a real estate transaction is straightforward. The test is placed at the beginning of the inspection period, and results are typically available before the inspection objection deadline.
What Happens If Radon Levels Are High?
A high radon test result is not a deal-breaker. Radon mitigation systems are effective, relatively affordable (typically $800 to $2,500 installed), and have a minimal visual footprint. A licensed radon mitigation contractor installs a sub-slab depressurization system that draws radon from beneath the foundation and vents it safely outside.
Once a mitigation system is installed and verified, the problem is solved. Many buyers use the radon test results as a negotiating point to have the seller cover the cost of mitigation prior to closing.