Radon Testing During a Home Inspection

Yes, radon should be tested during the home inspection. Order the radon test at the same time as the general inspection so the results come back inside your contingency window. That leaves time to ask for a system or a credit. In Pennsylvania, use a PA DEP-certified tester so the results are reliable and hold up in negotiations.

This guide covers why timing matters, how a real estate radon test works, what the results mean and when to plan radon mitigation for a house sale.

Why test radon during the inspection

Radon is a colorless, odorless radioactive gas that forms when uranium breaks down in soil and rock. You cannot see or smell it, and it causes no immediate symptoms. The EPA estimates it is linked to about 21,000 lung cancer deaths a year in the U.S. The only way to know a home's level is to test.

York County is in EPA Radon Zone 1, the highest-potential category. Many homes here test above the EPA action level of 4.0 pCi/L. For a buyer, the inspection contingency is the best chance to find out and negotiate a fix. Once that window closes, the cost of a system is usually yours.

How timing works with the contingency

In a standard Pennsylvania agreement of sale, the buyer has a set number of days to finish inspections and respond. The standard PAR form defaults to 10 days if the parties leave it blank. A radon test eats a good part of that time:

Add it up and a radon test can take four to five days from booking to report. If you wait until after the general inspection to order it, you may run out of time to negotiate. Book both on the same day.

Who should do the test

Pennsylvania requires anyone who performs radon testing for another person to be certified by the PA DEP Radon Division. Many home inspectors in York hold radon testing certification, or work with a certified tester. Ask for the certification number before the test.

A home test kit placed by the buyer is not a good choice for a sale. It lacks the safeguards that Pennsylvania rules require for real estate tests, and the seller may not accept the result.

What a real estate radon test looks like

Most real estate tests in York use a continuous radon monitor, a small electronic device that records readings every hour. Some testers use passive charcoal canisters, which go to a lab after the test.

Pennsylvania's testing rules for certified testers include:

• Placement in the lowest livable level, often the basement if it could be used as living space.
• Closed-house conditions: windows closed and exterior doors closed except for normal entry and exit.
• Anti-tampering devices that show if the monitor was moved.
• A signed conditions agreement and a posted "radon test in progress" notice.
• Normal HVAC operation, and any existing radon system must be running.

These steps protect both sides. Our guide on radon test tampering explains how monitors catch interference.

How to read the results

The report shows an average radon level for the test period, in pCi/L.

• Below 2.0 pCi/L: Below the range where the EPA suggests action, though the EPA notes no level of radon is completely safe.
• 2.0 to 3.9 pCi/L: The EPA says to consider fixing the home.
• 4.0 pCi/L or higher: At or above the EPA action level. The EPA recommends fixing the home.

Look at the hourly data too. Steady readings with daily ups and downs are normal. A sudden drop that lines up with a temperature change can be a sign that a window was opened.

What to do with a high result

If the test shows 4.0 pCi/L or higher, you have options under your inspection contingency:

1. Ask the seller to install a system and provide a passing clearance test before settlement.
2. Ask for a credit or price reduction so you can install after closing.
3. Accept the home and plan the install yourself.
4. End the agreement, as your contract allows.

Get a written mitigation quote before you send your request. It ties your ask to a real number. If you are weighing a credit against a seller-installed system, see our comparison of radon credit at closing vs. seller-installed system.

What if the home already has a system?

Test anyway. Pennsylvania rules require the existing system to be running during the test. A passing result confirms the system works. A high result usually points to a repair, such as a new fan or more sealing.

Season and York homes

Radon levels often run higher in winter, when homes stay closed and heated air rising indoors pulls soil gas in from below. A winter test may read higher than a summer test of the same house. That is normal. The test result you get is what the negotiation is based on, so do not try to wait out a season during a sale.

Key takeaways

• Order the radon test the same day as the home inspection.
• A real estate radon test takes about four to five days from booking to report.
• Use a PA DEP-certified tester, not a home kit.
• At or above 4.0 pCi/L, negotiate a system, a credit or a price change.
• Test even if the home already has a system.

Frequently Asked Questions

Can a home inspector do the radon test?

Yes, if they are certified by PA DEP for radon testing. Ask for their certification number.

How long does a radon test take during an inspection?

The test itself runs at least 48 hours. With setup and reporting, plan on about four to five days.

Can I skip the radon test if the seller already tested?

You can, but a new test gives you current results under your own control. Older results may not reflect the home today.

High result inside your contingency?

We can send a written quote fast and schedule the install and clearance test around your settlement. Call (717) 356-3035 any time for a same-day callback.