Should You Test for Radon in New Construction Homes?

Why "New" Doesn't Mean Radon-Free

It's a natural assumption: a home built last year, with new framing, new concrete, and a code-compliant foundation, should be free of the problems that turn up in older houses. Radon, though, doesn't work that way. Radon is a naturally occurring gas produced by the breakdown of uranium in soil and rock — it comes up from the ground beneath a house, not from anything inside the structure itself. A brand-new slab, a fresh crawl space, or a newly poured basement sits on the same ground an older home in the same neighborhood sits on. If that soil produces radon, a new foundation doesn't stop it from finding a way in.

For homeowners in Kannapolis, Concord, and Landis, this matters because radon risk is a property of the land, not the building. A new-construction buyer who assumes a fresh build means a radon-free build is making a assumption the science doesn't support — and it's an assumption that can leave a real question mark unanswered for years if no one ever tests.

How Radon Gets Into a New Home

Radon enters a home through the same pathways regardless of the structure's age: cracks in a foundation slab, gaps around plumbing penetrations, sump pump openings, and the porous joints where a foundation wall meets a floor. New construction has all of these features too. Concrete cures and settles over time, which means even a home built to current code can develop small cracks and gaps in its first years. Modern homes are also often built tighter for energy efficiency, which can reduce natural air exchange and, in some cases, allow soil gas to concentrate indoors rather than dissipate.

None of this means a new home is guaranteed to have a radon problem — many don't. It means a new home's radon level is genuinely unknown until someone measures it, exactly like any other home. The only way to know whether your specific new build has elevated radon is to test the air inside it.

When to Schedule a Test for a New-Build Home

Homeowners who've recently closed on new construction in Kannapolis, Concord, or Landis don't need to wait for a specific milestone or anniversary — testing can be scheduled once the home is enclosed, the HVAC system is operating normally, and the household is living in it under regular day-to-day conditions. A certified test measures the air as it actually behaves in the finished, occupied home, which is the most useful reading a new owner can have.

If you purchased new construction and a radon test was never part of the closing process, that's common — radon testing isn't a universal requirement for new-build sales the way it often is in resale transactions with a buyer's inspection contingency. That gap is exactly why so many new-construction owners end up with no radon data at all: no one required it, so no one ordered it. Scheduling a test now, whether the home is one month old or several years old, closes that gap.

Builders in Kannapolis, Concord, and Landis close new homes across every season, and test timing should follow occupancy readiness rather than the calendar. If you closed in spring or summer when windows are more likely to be left open, talk to your tester about scheduling a window when the home can be kept under closed-house conditions for the full 48-hour period — an accurate reading depends on that, regardless of what season your closing happened to land in.

North Carolina Building Code and Radon-Resistant Construction

Unlike states in officially designated high-radon zones, North Carolina's residential building code does not require radon-resistant new construction (RRNC) techniques on every new home. The International Residential Code's Appendix F — passive sub-slab depressurization piping, a sealed vapor barrier, and a rough-in for a future fan — is the industry-recognized standard for building radon resistance into a new home from the ground up, but adopting it is optional for builders in Cabarrus County and the surrounding Piedmont unless a specific jurisdiction has made it mandatory.

That means whether your new-construction home in Kannapolis, Concord, or Landis has any radon-resistant features at all depends entirely on your specific builder's choices, not a code requirement everyone follows. Some builders install the passive piping as a value-add; many do not, because it isn't required for a certificate of occupancy. Either way, a code-compliant new home is not the same as a radon-tested home. Code compliance addresses structural safety and life-safety systems; it says nothing about the radon concentration actually present in your finished, occupied house. The only way to know that number is to measure it.

Why Your Builder's Warranty Doesn't Cover Radon

New-construction buyers often lean on a builder's warranty — commonly a 1-2-10 structure covering one year of workmanship, two years of major systems, and ten years of structural defects — as a general safety net. Radon isn't part of that safety net. A builder's warranty covers construction defects: things the builder did wrong relative to code or workmanship standards. Radon is a naturally occurring condition of the soil beneath the home, not a defect the builder introduced, so it falls outside virtually every standard builder warranty's scope, including the structural coverage in most 1-2-10 plans.

Practically, that means there's no one to file a warranty claim with if your new home tests high for radon — mitigation is a cost you'd bear directly, the same as any other homeowner. Knowing that up front is exactly why testing early matters: if a mitigation system does turn out to be necessary, you want that information while you're still budgeting for a new home, not as a surprise expense discovered years later.

Why False Confidence Is the Real Risk

The practical danger with new construction isn't that radon is more likely in a new home — it's that owners are less likely to think about it at all. A homeowner who buys an older house is more likely to have encountered the topic during the transaction, or to have heard about it from a neighbor with an older home. A new-construction buyer, surrounded by warranties, inspection reports, and a builder's assurances about a code-compliant structure, has less reason to ever raise the question — even though the answer is just as unknown as it would be for a 40-year-old house on the same street.

That's the false confidence worth avoiding: treating "new" as a proxy for "tested" or "safe." A certified radon test is the only way to replace that assumption with an actual answer, one way or the other.

Getting an Unbiased Answer

Wightman Inspection Group provides independent radon testing for existing homeowners throughout Kannapolis, Concord, and Landis — including owners of new-construction homes who want to know where they stand. We use certified, professionally calibrated equipment to measure radon levels in your home, and we provide testing only. We do not sell or install mitigation systems, so there's no incentive on our end to shade a result one way or another — you get an accurate reading, whatever it turns out to be, without pressure to buy a system from the company that ran the test.

A standard residential radon test from Wightman Inspection Group costs $175–$225. If your new-construction home has never been tested, that's a modest cost for a definitive answer — and one less unknown to carry as a new homeowner.