You should get a radon test with your home inspection, and the timing matters more than most home buyers realize. Radon is a colorless, odorless radioactive gas that is the second leading cause of lung cancer in the United States. You cannot detect it without testing, and levels vary from house to house even on the same street.
At InsideOut Inspections Plus, we see firsthand how often radon gets skipped during home purchases. The health and financial consequences can be significant. This post covers what radon is, why testing belongs alongside your home inspection, how the process works, and what to do if results come back elevated.
What Is Radon and Why Does It Matter?
Radon is a radioactive gas produced when uranium naturally breaks down in soil, rock, and water. It rises up through the ground and can seep into any home (new or old, tight or drafty, basement or slab). Outdoors, it disperses quickly. Indoors, it accumulates.
Long-term exposure to elevated radon levels raises the risk of lung cancer, especially for smokers or anyone with a history of respiratory illness.
Per EPA radon health risk guidance, radon exposure is responsible for about 21,000 lung cancer deaths in the United States every year. The EPA and the Surgeon General both recommend testing every home.
How Radon Enters a Home
Radon travels upward from the soil and finds its way indoors through:
- Cracks in foundation walls or floors
- Gaps around pipes, drains, and sump pumps
- Crawl spaces with exposed soil
- Construction joints and wall-floor junctions
No home is immune. Radon has been found at elevated levels in every state, including Michigan and Ohio.
What the EPA Says About Radon Levels
Radon is measured in picocuries per liter (pCi/L). The EPA recommends mitigation when levels reach 4 pCi/L or above.
The agency also suggests considering mitigation for levels between 2 and 4 pCi/L, since there is no fully safe threshold. Lower is always better.
Is Radon Testing Part of a Standard Home Inspection?
Radon testing is not a standard part of most home inspections. A typical home inspection covers structural components, electrical and plumbing systems, HVAC, roofing, and major visible deficiencies. It does not include air quality testing for radon, mold, or other environmental hazards.
Radon testing is an ancillary service that must be requested separately. Not every home inspector holds a radon testing license. At InsideOut Inspections Plus, our inspectors are licensed by the state of Michigan and Ohio and use Radstar Continuous Monitors, which are far more accurate than over-the-counter charcoal canister kits.
If you are scheduling a home inspection, ask specifically whether radon testing is offered and whether it can be bundled the same day. Combining both services in one visit is the most efficient and cost-effective approach.
Radon Testing and Home Inspections
Scheduling radon testing alongside your home inspection is the smart move for three clear reasons.
The Best Window to Test
The best time to test for radon is before you close. Once you own the home, the negotiating leverage shifts entirely to you. If testing happens before closing and results come back at or above 4 pCi/L, you can ask the seller to install a radon mitigation system as a condition of the sale, or negotiate a price reduction to cover the cost yourself.
After closing, that option is gone. A mitigation system runs $800–$2,500, depending on the home’s foundation type. Testing before closing costs a fraction of that and puts you in control.
Radon Levels Vary House to House
You cannot predict a home’s radon level based on its neighborhood, age, construction type, or whether the neighbor’s home tested clean. According to the American Lung Association, elevated radon has been found in every state and can vary significantly from one property to the next. The only way to know a specific home’s level is to test it.
Even if the seller provides a previous radon test result, that reading may be outdated. Radon levels shift with seasons, soil changes, and home modifications. A fresh test at the time of inspection gives you current, reliable data.
Your Results Can Affect the Sale
A radon test result at or above 4 pCi/L is not a dealbreaker. Radon problems can be fixed. A qualified contractor can install a sub-slab depressurization system that vents radon outdoors before it accumulates indoors. These systems work well and require minimal maintenance.
What the result does is give you information. Information is leverage. You can use it to negotiate, plan, or simply make an informed decision about the home you are about to buy.
How Radon Testing Works at InsideOut Inspections Plus
InsideOut Inspections Plus uses Radstar Continuous Monitors, not passive charcoal canisters. Here is what the process looks like:
- Placement: The Radstar monitor is placed in the lowest livable area of the home (typically the basement) at the time of your home inspection.
- Data collection: The monitor collects an hourly reading for a minimum of 48 hours under closed-house conditions.
- Upload: After 48 hours, readings are transmitted electronically to Radstar for analysis.
- Report delivery: You receive a detailed report within 24 hours of data receipt, clearly stating the measured pCi/L level and whether further action is recommended.
Our team is available to walk you through the results and answer any questions. Same-day reports, licensed inspectors, and clear communication: that is how we approach every service we offer. If you want to bundle radon testing with your home inspection services, schedule through our site, and we will set everything up for the same visit.
Related Questions to Explore
- Is radon testing required during a home inspection? No, radon testing is not legally required during a home inspection in most states, including Michigan and Ohio. However, the EPA recommends testing every home being bought or sold, regardless of location. Most buyers request it as an optional add-on.
- How much does a radon test cost during a home inspection? The cost ranges from $145 to $700 depending on location and the type of test used. Professional continuous monitor testing is more accurate than DIY charcoal kits and is often bundled with a home inspection for savings.
- What radon level is dangerous in a home? The EPA action level is 4 pCi/L. At or above that level, mitigation is recommended. However, the EPA also suggests taking action at levels between 2 and 4 pCi/L since long-term exposure at any elevated level carries risk. The average indoor radon level in the U.S. is about 1.3 pCi/L.
- Does the buyer or the seller pay for radon testing? In most real estate transactions, the buyer pays for radon testing as part of the inspection process. If results come back elevated, the buyer can negotiate with the seller to have a mitigation system installed or to receive a credit toward one. Some sellers test in advance before listing to avoid surprises.
- Can new homes have high radon levels? Yes. New construction does not guarantee low radon. Radon comes from the soil beneath the home, not from building materials or age. Some new homes are built with radon-resistant features, but even those should be tested. Every home, new or old, should have a radon test before occupancy.
When to Call a Professional for Radon Testing
A DIY charcoal canister kit from a hardware store can give you a rough picture. But for a home purchase, you need accurate, defensible data. That means professional testing.
Call a licensed radon testing professional when:
- You are buying a home and need results before closing
- A previous test is more than two years old
- You have finished a basement or made foundation modifications
- Your area is in a high-radon zone (both Michigan and Ohio have significant radon-prone regions)
- You installed a mitigation system and want to confirm it is working
InsideOut Inspections Plus is licensed in both Michigan and Ohio to provide professional radon testing using continuous monitors. We offer radon testing as a standalone service and as an add-on to any home inspection.
Conclusion
Getting a radon test with your home inspection is one of the simplest, most cost-effective things you can do before buying a home. Radon is real; it is present in every state, and it is undetectable without testing.
The good news: it is also fixable, and testing before closing gives you the information and the leverage to address it on your terms.
Key takeaways:
- Radon is the second leading cause of lung cancer in the U.S., and you can not see, smell, or taste it.
- Radon testing is not part of a standard home inspection. Request it specifically as an add-on.
- Buying a home in Michigan or Ohio? The ideal time to test is during your home inspection, before closing.
Ready to add radon testing to your upcoming inspection? Schedule online or call us today!
