Charleston homeowners don’t worry much about radon. But it deserves a spot on the worry list. Levels of this radioactive gas rise in the colder part of the year. Radon levels in winter surge to the highest levels.
Let’s discover why radon levels rise in colder months and how a Charleston home inspection can save your health by helping you take the right step based on radon levels.
Let’s Recall: What Radon Is
Radon is a naturally occurring radioactive gas that forms when uranium in soil and rock breaks down. It can seep into a home through cracks and gaps, especially where the house touches the ground. You can’t see or smell this gas. The only way to know whether your home has a higher level is to have a test.
Health-wise, radon is a big deal because long-term exposure increases lung cancer risk. Public health agencies treat it seriously: the CDC emphasizes testing and mitigation when levels are elevated.
What Number is Too High for Radon
There is no safe level of exposure to radon. The average indoor radon concentration in U.S. homes is about 1.3 pCi/L. The Environmental Protection Agency (EPA) recommends that Americans consider fixing their homes to reduce radon levels to between 2 pCi/L and 4 pCi/L.
The EPA also states that radon is found everywhere in indoor and outdoor air. All kinds of buildings can be affected by radon. It is recommended that homes should be fixed if the radon level is 4 pCi/L (picocuries per liter) or higher.
Why Radon Levels in Winter Tend to Rise
Indoor radon concentrations are often higher in winter than in summer. This happens because of the following reasons:
You Close the House Up
Even in Charleston, winter is when people keep windows closed more often, especially at night, during rain, or cold snaps. Less fresh-air exchange means any radon that enters has more time to build up indoors.
The EPA’s real estate radon guidance talks about closed-house conditions for short-term tests because sealing the home changes the indoor concentrations.
The “Stack Effect” Pulls More Gas
When your home is warmer inside than outside, warm air rises and escapes from the upper areas (tiny gaps around attic hatches, recessed lights, bathroom vents, etc.). That upward escape creates a slight vacuum in the lower part of the house, which can pull in air from the soil.
If your home is sitting over radon-producing soil, that pulled-in air can carry more radon. You don’t need a freezing winter for this effect, just a consistent temperature difference between indoors and outdoors.
Weather Change Influences Soil Gas Movement
Winter weather systems bring changes in barometric pressure, rainfall patterns, and soil moisture. All these factors affect how gases move through soil. It can also influence how your home interacts with the ground beneath it.
This seasonal variation, linked to environmental conditions, causes higher radon levels in your home.
Charleston Homes & Crawl Spaces
Charleston has many raised homes with crawl spaces. Crawl spaces are not bad, but they do create an interface between the home and the ground. If the crawl space has gaps, poor sealing, or certain airflow patterns, radon entry becomes easier.
What Makes Radon Levels Higher in February
In Charleston, February commonly sits in that sweet spot where:
- It’s still one of the coolest months
- Heating usage may still be happening
- The house has been in “winter mode” for weeks already
- Weather swings can create strong pressure
Even simple climate summaries show February is part of Charleston’s colder season. The nights remain colder in this month, and homes have less ventilation. You can understand it this way:
- December: Windows are still sometimes open, and people are in and out for the holidays. The temperature may vary this month.
- January: The home starts staying closed more consistently.
- February: The homes have often been closed long enough for patterns to show up. This tends to raise radon levels in winter.
Test Your Home For Radon with Charleston Home Inspection
Radon is a radioactive gas. Its higher levels can have adverse effects on your health. In your Charleston home, radon shoes peak in February. It usually happens when the home is closed up, the temperature difference is bigger, and the building pulls air from the ground.
To maintain a healthy living environment inside your property, you must schedule regular radon tests. Reach out to Charleston Home Inspection to find out whether your home has higher radon levels and how to address them.
