You cannot see or smell radon, yet it shows up often in Lehigh County homes. If you are buying or selling, you want clear, local guidance that keeps your family safe and your transaction on track. In this guide, you will learn what the EPA action level means, how to test with confidence, what fixes actually work, and how to handle radon in a real estate deal. Let’s dive in.
Radon basics in Lehigh County
Radon is a naturally occurring radioactive gas that can build up indoors and increase lung cancer risk over time. The EPA uses an action level of 4 pCi/L to guide decisions in homes. If your results are at or above that level, you should take steps to reduce it. You can review the EPA’s overview of indoor levels and risk for more background on why this matters (EPA radon levels and risk).
Pennsylvania sees elevated radon more often than most states. About 40% of tested Pennsylvania homes show results at or above 4 pCi/L, so routine testing is smart across Lehigh County (PA DEP: radon in the home). Local results vary by house and neighborhood, and the Pennsylvania DEP shares test data by ZIP code so you can explore trends near you (DEP radon data by ZIP).
Why you should test every home
Testing is the only way to know your level. Radon can vary from one home to the next, even on the same street, and it can change seasonally. National health guidance recommends that all homes be tested and retested over time, especially during a sale or after major renovations (CDC: radon testing basics).
How radon testing works
Short-term vs. long-term tests
Short-term tests run from 2 to 90 days and are common in real estate deals because they provide quick results. Long-term tests run more than 90 days and give a better year-round average. If a short-term result is 4 pCi/L or higher, plan a follow-up test to confirm before you decide next steps (CDC: radon testing basics; Test devices overview).
Set up for accurate results
For short-term tests, follow the instructions closely and keep “closed-house” conditions as directed so you get a reliable snapshot. Place the device on the lowest level you use regularly, away from drafts and exterior walls (Test devices overview).
Testing during a sale in Lehigh County
If you are buying, include a radon test in your inspection period and consider hiring a DEP-certified tester who uses a continuous monitor. Pennsylvania requires certification for professionals who place and retrieve devices or perform mitigation (PA radon certification).
If you are selling, you are not required by state law to test before listing, but you must disclose any known environmental hazards and any prior radon results on the Pennsylvania Seller’s Property Disclosure Statement (PA seller disclosure rule). Many sellers choose to test before listing so they can address issues up front.
Where to find kits and resources
PA DEP and partners sometimes offer free or discounted test kits and share guidance on testing and mitigation. You can also check current ZIP-level trends and learn more about radon statewide on the DEP’s radon pages (DEP radon data by ZIP).
What if your test is high?
Proven fixes and typical costs
The most common and effective fix is active sub-slab depressurization, which uses a fan and vent piping to draw soil gases from beneath the foundation and release them safely above the roofline. Crawlspaces often use a sealed membrane with suction. Sealing cracks is helpful but is not a standalone solution. Typical professional systems often range from about $800 to $2,500 depending on your foundation and layout (EPA mitigation overview and costs).
Who should install in Pennsylvania
Mitigation should be designed and installed by a DEP-certified radon contractor. Ask for their certification number, references, and a written plan that includes post-mitigation testing. Installations often take a day or two, depending on complexity (PA radon certification).
Verify results and maintain
After installation, complete a post-mitigation test within 30 days to confirm the system reduced levels below 4 pCi/L. Retest every 1 to 2 years and after major renovations. Fans can run for years but may need replacement over time (Post-mitigation guidance).
Radon in well water
If your home uses private well water, radon in the water can add to indoor levels, especially during showers and laundry. The usual approach is to test the air first. If air levels remain elevated or you suspect a water source, water testing and point-of-entry treatment like aeration or granular activated carbon can help, depending on your setup (EPA Q&A: radon in water).
Radon and your real estate deal
Seller steps and disclosure
- Consider pre-list testing so you can share results and, if needed, show buyers a successful mitigation with documentation.
- Disclose any known test results and system details. Include installer info, the post-mitigation result, and any warranty. This builds trust and helps avoid last-minute issues (PA seller disclosure rule).
Buyer protections and negotiation
- Include a radon test contingency in your offer. If results confirm 4 pCi/L or higher, you can request seller-paid mitigation, a price credit, or for the seller to mitigate before closing.
- Require post-mitigation testing and documentation if a system is installed before settlement (CDC: radon testing basics).
Local tips for Lehigh County homes
- Check DEP’s ZIP-level data to understand typical basement results in areas you are exploring (DEP radon data by ZIP).
- Plan your radon test early in the inspection period so you have time for follow-up if needed.
- If you are building new, ask your builder about radon-resistant features during planning. It is easier to install in new construction than after move-in.
Protecting your household and your transaction is achievable with the right steps. If you want local guidance on how radon fits into your buying or selling plan in Lehigh County, connect with Shabana Pathan for clear next steps and trusted representation.
FAQs
What is a safe radon level for a Lehigh County home?
- The EPA uses an action level of 4 pCi/L; if your result is at or above that level, you should take steps to reduce it (EPA radon levels and risk).
Do Pennsylvania sellers have to test for radon before listing?
- No statewide requirement to test before listing, but sellers must disclose known hazards and any prior radon results on the Seller’s Property Disclosure Statement (PA seller disclosure rule).
Who can perform radon testing or mitigation in Pennsylvania?
- Professionals who place or retrieve devices and those who mitigate must be DEP-certified; ask for certification and post-mitigation test documentation (PA radon certification).
How long does radon mitigation take and what does it cost?
- Many systems install in about one day and typical costs often range from about $800 to $2,500 depending on the home and design (EPA mitigation overview and costs).
Where can I find Lehigh County radon data and test kit resources?
- The DEP shares test data by ZIP code and offers public outreach resources that can include seasonal kit programs and provider information (DEP radon data by ZIP).
