Pennsylvania does not require radon testing to sell a home, but sellers must complete a Seller's Property Disclosure Statement that asks about radon and other hazardous substances, and any known elevated test results must be disclosed. Many buyers test for radon during the inspection window because Pennsylvania has some of the highest radon levels in the country.
How Radon Disclosure Works in Pennsylvania
Radon is an invisible, odorless radioactive gas that seeps into homes from the ground, and Pennsylvania has some of the highest radon levels in the country. The state Department of Environmental Protection recommends testing every home. But what does the law require when a home is sold?
The short answer: Pennsylvania does not require a radon test as a condition of sale, and there is no separate state radon disclosure form. Instead, radon is covered by the Seller's Property Disclosure Statement, which every residential seller in the state must complete. That form asks whether the seller is aware of hazardous substances on the property, including radon, and it requires the seller to disclose the results of any radon test they have had performed.
What Sellers Must Disclose
The Seller's Property Disclosure Statement is the vehicle for radon disclosure in Pennsylvania. If a seller has tested the home and knows the result, including an elevated result, that information goes on the disclosure. If the seller has no knowledge of a test, the form reflects that. The seller must answer honestly; concealing a known radon problem is a disclosure violation, and Pennsylvania's disclosure law gives buyers remedies if a defect was hidden.
Sellers who tested and installed a mitigation system should provide the test results and system documentation, which is genuinely good news for a buyer. A mitigated home with a working radon system is a safer home, and the paperwork proves it. Sellers who have never tested simply have nothing to report, and that is a normal, honest answer in Pennsylvania.
What Buyers Should Do
Because testing is not required, the buyer's protection is to test for radon during the inspection window of the Agreement of Sale. Radon tests are inexpensive, take a few days, and are available through inspection companies in the Philadelphia region. The standard practice is to run the radon test in the same window as the home inspection so the results arrive together.
If the test comes back at or above the EPA action level of 4.0 picocuries per liter, the buyer can negotiate. The options are a mitigation system, a credit, or walking away under the inspection contingency. Radon mitigation is a well-established fix, a vented fan system that professionals install, so an elevated reading is not a deal killer; it is a negotiable cost with a real solution.
The Interaction With the Contract
In a typical Pennsylvania sale, the radon test, the home inspection, and the sewer check all run inside the same contingency window. The buyer's right to terminate for inspection findings covers radon findings the same way it covers a failing roof. The agreement does not need a special radon clause for this to work, though buyers can add one if they want the result tied to the contract explicitly.
Some townships in the region, and some condo associations, have their own radon expectations, but Pennsylvania has no state mandate that a home be tested before sale. The system relies on disclosure of what is known and buyer testing for what is not. See how the inspection contingency protects you for how the radon result gets negotiated.
What About Newer Homes
Newer construction is not automatically radon safe. Radon depends on geology, not age, and new homes built with radon-resistant features are the ones to ask about. When buying a new build, ask the builder whether the home includes a passive radon system or a vapor barrier, and still test after closing, which is the DEP recommendation for every home in the state.
Condo buyers in high-rise buildings generally face less radon risk because the ground contact is limited, but ground-floor units and townhomes with slab foundations should still be tested. The disclosure rule is the same across all of them: report what you know, test what you do not.
Key Takeaways on Radon
Radon in Pennsylvania is a testing story, not just a disclosure story. Remember these five points.
- Testing is not required: Pennsylvania does not mandate a radon test at sale
- Disclosure is required: known results go into the Seller's Property Disclosure Statement
- Buyers test anyway: run the radon test inside the inspection window
- Know the action level: 4.0 picocuries per liter triggers mitigation recommendations
- Mitigation works: a professionally installed vented fan system reliably lowers levels
Elevated readings are negotiable, not fatal; a disclosed problem with a working mitigation system is a safer home.
Smarty's Advice Expert Insight
John Smart (Smarty) · Smarty Home Solutions / eXp Realty Agent, AI Certified Agent
Test, do not assume. Buyers: run a radon test in the inspection window and negotiate mitigation if the level is elevated. Sellers: answer the disclosure honestly and hand over any test records, because a disclosed problem is a solvable problem.
John Smart, AI-Certified Agent with eXp Realty includes radon testing in his buyers' inspection plans across the Philadelphia region and works with certified mitigation contractors when a reading comes in high. Call 215-598-6848 or schedule a free consultation. No obligation, just straight answers.