A snowman sits in the front yard of a red craftsman-style house. The landscaping and sidewalk are covered in snow.

How To Prevent Radon Buildup in Winter Months

Winter is when most of us find solace indoors, cozying up in the comfort of our homes. However, while we focus on staying warm, another element may silently creep in, threatening the very air we breathe: radon.

Radon is a naturally occurring radioactive gas that’s invisible and odorless. Though it exists in low levels outdoors, it can become concentrated indoors, especially in the winter, posing a severe health risk to homeowners.

In this post, we’ll explain how to prevent radon buildup in winter months and create a safer living environment for your family. By the time you’re done reading, you’ll have a solid understanding of the elevated radon risk during colder months, how to detect its presence, and actionable measures to keep this hazardous gas at bay.

Understanding Radon: The Basics

Before jumping into prevention, it helps to understand what radon is and why it matters. Radon is a radioactive gas that’s produced when uranium in soil breaks down. This gas can enter your home through foundational cracks and other openings, accumulating to unsafe levels over time.

When present in high concentrations, radon poses a serious health hazard, as it’s a common cause of lung cancer. Fortunately, you can manage and prevent radon exposure with proper testing and mitigation techniques.

The Risk of Radon in Winter: Why Levels Are Higher

Radon levels are often higher in winter for several reasons, making it an important season to monitor and manage this invisible threat. Here’s what you need to know:

  1. Homes are tightly sealed: Colder temperatures lead families to keep windows and doors tightly sealed to conserve heat. While this practice improves energy efficiency by keeping warm air inside, it also reduces ventilation, which would normally help to dilute and lower radon levels in the home. Without sufficient airflow, radon gas can build up indoors over time, increasing health risks.
  2. Heating systems increase the stack effect: During winter, heated air rises to the top of a home, creating a vacuum-like pressure that pulls air—and radon gas—from the soil below into living spaces. This natural phenomenon is known as the stack effect. It’s especially pronounced in colder climates where heating systems are working overtime to maintain comfortable indoor temperatures.
  3. Snow and frozen soil create a barrier: When the soil freezes, it creates a barrier that traps radon gas beneath the surface. It’s now more difficult for radon to escape freely into the atmosphere. Instead, it’s forced to find paths with less resistance, which is why it enters homes through cracks in the foundation, construction joints, or other structural openings.

Given these factors, winter becomes a critical time for homeowners to focus on radon mitigation strategies. Testing your home for radon can reveal whether levels are elevated. If tests indicate high levels, installing a radon mitigation system or improving ventilation can protect your household from long-term exposure to this harmful gas. Regular monitoring and proactive measures are key to keeping radon levels in check year-round.

A heat pump sits outside of a home on a snowy day. A tree stands nearby as sunlight shines on the side of the white house.

Signs of Radon Buildup: Potential Symptoms To Look For

A key point about radon is that it’s impossible to see, smell, or taste. Unfortunately, this means there are no clear physical signs of radon presence. Testing is the only reliable way to measure radon concentrations in your home.

That said, there are circumstances that may hint at the need for testing. If members of your household experience these symptoms, it might be worth examining whether radon exposure could be a contributing factor:

  • Persistent respiratory issues
  • Unusual fatigue
  • Frequent headaches

Homes with a known history of radon or visible damage to the foundation, walls, or floors should also be tested regularly. Likewise, if your neighbor has experienced high radon levels, your property may be at risk too. Testing provides peace of mind and ensures you’re addressing radon proactively.

Effective Preventative Measures

When deciding how to address radon buildup in the winter, there are simple DIY solutions and professional options to consider. Here are your options:

  • Improve ventilation: Increase airflow in your home. Even cracking a window for 15 minutes a day can help improve the air quality and reduce radon concentration, albeit temporarily.
  • Seal cracks and gaps: Closing gaps in the foundation is another effective method. Radon can enter your home through even the smallest crevices, so inspect your basement flooring, walls, and utility seams for openings. Using radon mitigation supplies such as silicone caulk or epoxy resin creates a tighter barrier to keep radon out.
  • Install a mitigation system: For those seeking a more advanced approach, radon mitigation systems are an excellent investment. Professional radon mitigation uses a negative pressure system beneath your home’s foundation slab to prevent radon gas from entering. This method significantly lowers indoor radon levels. There are also DIY options for budget-conscious homeowners.
A woman wearing jeans and a T-shirt opens the blinds in her living room. Outside, snow blankets the streets below.

The Importance of Regular Testing

Testing for radon isn’t something you do once and forget about. Radon levels can fluctuate over time due to environmental factors or structural changes in your home. It’s a best practice to conduct radon testing every one to three years, even if you have a mitigation system in place. Test kits are available online or at local hardware stores, offering an affordable, convenient way to monitor your home’s radon levels.

If a test reveals abnormally high levels, hiring a licensed radon professional can help. Professionals use specialized equipment to measure radon concentrations and recommend the best course of action based on their findings. You can also invest in a continuous radon monitor so you can track fluctuations throughout the year.

Create a maintenance plan to routinely inspect your foundation and ensure existing mitigation systems work as intended. By staying proactive, you can protect your health and preserve the value of your property.

Keep Your Home Safe All Winter

Understanding how to prevent radon buildup in winter months is essential for maintaining a healthy home environment. Winter conditions often create the perfect storm for radon concentration, making it critical to test your home, seal structural gaps, and invest in effective mitigation systems. By following the steps outlined in this guide, you can enjoy peace of mind knowing you’ve taken measures to safeguard your family against the dangers of radon.