Radon Testing Before You Buy, Sell, or Finish a Basement

Nobody Can Tell You Your Radon Level by Looking

Radon doesn’t care if a house is old or new, drafty or tight, with a basement or on a slab. The Pennsylvania Department of Environmental Protection says as much, and about 40% of Pennsylvania homes tested come in above the EPA’s action level. A test is the only way to know where yours sits.

That’s all radon testing is: a measurement, taken the right way, so you can make a decision. Most tests come back fine. When one doesn’t, you’ll have a real number to plan around, and a clear next step in radon mitigation.

Short-Term and Long-Term Tests

There are two kinds, and each has a job.

• Short-term tests run from 2 to 90 days. Home sales almost always use a short-term test, because nobody wants to wait three months to close.
• Long-term tests run more than 90 days. They give a better picture of your average level across seasons, which matters when you’re living in the house for years.

Either way, the house is kept closed during the test: windows shut, doors used only for normal coming and going. The test goes on the lowest level that’s lived in or could be, away from drafts, outside walls, and humid rooms like bathrooms and laundry areas.

Radon Testing for Home Sales

This is where most York County homeowners run into radon for the first time. The buyer’s inspector sets a test during the inspection window, the number comes back, and everybody wants to know what it means right now.

If you’re selling, testing before you list takes the surprise out of it. If the number is high, you can have a system in and a passing follow-up test before a buyer ever asks.

If you’re buying, ask for the result in writing and ask whether the house already has a system. A pipe on the side of the house doesn’t guarantee the fan is running. Look at the gauge on the pipe. If both sides of the liquid are level, that system isn’t pulling, and you’ll want the fan checked as part of the deal.

When to Test Your Own Home

• You’ve never tested, or you can’t remember the last time
• You’re about to finish the basement or turn it into a bedroom, office, or playroom
• You’ve added on, replaced the slab, or done big foundation or drainage work
• A neighbor or family member nearby tested high
• You had a system installed and it’s been two years since the last test

What Your Result Means

A result of 4.2 is not an emergency, and a result of 20 isn’t a reason to move out tonight. Radon risk comes from years of breathing it. Both results mean the same thing: get a system in, then test again to prove it worked.

Testing After a System Goes In

Every system we install gets a follow-up test once the fan has been running at least a day. After that, retest every two years and any time you renovate the lowest level. If a later test comes back higher than the one after install, something changed, and it’s often the fan. That’s a radon fan replacement visit, not a whole new system. We do this work for homeowners all over York County, from the Maryland line up to Dillsburg.