Radon is an invisible threat that affects millions of homes and businesses across the U.S. Most people are aware of radon, but many are still surprised to learn just how easily it can enter your home or business—and stay there undetected.
Because radon is colorless, odorless, and tasteless, you won’t notice it until you test for it. But understanding how it enters your property can help you take the right steps to protect your air quality and your health.
Here’s a breakdown of the most common radon entry points and how this dangerous gas makes its way inside—even in the cleanest, best-maintained homes.
🧱 Radon Comes from the Ground Beneath Your Home
Radon forms naturally as uranium breaks down in soil and rock. As a gas, it travels upward through the earth, searching for the path of least resistance. That path often leads straight into your home—especially through gaps and cracks in the foundation.
Radon levels are typically highest in basements and ground-level rooms, but the gas can move upward through the entire house over time.
🔍 Common Radon Entry Points in Most Homes and Businesses
Cracks in Concrete Slabs or Basement Floors
Small hairline cracks in your foundation may not seem like a big deal—but they’re the fast lane for radon gas. Even brand-new homes can have settling cracks that allow radon to seep in.
Gaps Around Pipes, Wires, or Plumbing Penetrations
Wherever pipes or wires enter your home—such as in the basement or utility room—there’s often a gap in the concrete or wall. These open channels make ideal radon entryways if not properly sealed.
Construction Joints and Expansion Gaps
Where foundation walls meet floors, or where slabs are poured in sections, there are joints that can open up slightly over time. These joints are common points of radon infiltration.
Sump Pump Pits and Drainage Systems
Your sump pit is designed to move water away from your home’s foundation—but it can also serve as an open door for radon gas if not sealed properly with an airtight lid.
Crawl Spaces with Exposed Soil
Homes with crawl spaces often have open soil or gravel underneath, which can allow radon to rise freely into the living space. Even with a vapor barrier, improper sealing can allow radon through.
Floor Drains and Unsealed Openings
Floor drains—especially in basements or utility rooms—can become unexpected radon entry points if they aren’t sealed or properly trapped.
💡 Can Radon Get Into New Homes, Too?
Yes! Many new homes are built with energy-efficient materials and airtight construction, which can actually trap radon inside more effectively. Unless a home has a properly installed active radon mitigation system, it’s still at risk—regardless of age, size, or location.
🧪 What Can You Do About It?
The good news: You can control and reduce radon—but only if you know it’s there.
✔️ Step 1: Test Your Home or Business
Use a radon test kit or hire a certified professional. Even if you already have a passive radon system, testing ensures it’s doing its job.
✔️ Step 2: Seal Entry Points (But Don’t Rely on Sealing Alone)
Sealing cracks and gaps helps reduce radon entry, but it won’t fully solve the problem on its own. Think of sealing as part of a complete solution.
✔️ Step 3: Install or Upgrade a Radon Mitigation System
An active radon mitigation system, which includes a fan and venting pipe, is the most effective way to pull radon gas from beneath your home and release it safely above the roofline.
✅ Final Thoughts: Radon Enters Quietly—But You Can Keep It Out
Radon is a serious health risk, but it’s completely manageable with the right steps. Knowing how it gets in is the first part of protecting your home and your family.
📞 Need to test or install a mitigation system?
Let SWAT Environmental help—our national team of certified radon professionals is here to make your home safer, from foundation to rooftop.
👉 Contact SWAT Environmental today for radon testing, mitigation, or expert advice.