Real estate radon testing is a protocol-controlled 48-hour test performed during a home sale, usually inside the buyer's inspection window, producing a defensible written report both parties' attorneys can rely on. In Plymouth County it runs $200 to $300 with priority scheduling, because the inspection clock doesn't wait.
Here's the pattern we see every month: buyer's inspector recommends a radon test, the result comes back 6.4, and suddenly a smooth transaction has a hostage negotiation bolted to it. Seller thinks the number is inflated. Buyer's agent wants a credit. Everyone's attorney is on the phone. The closing date starts to slide.
Every part of that is avoidable with a proper test, run early, by a party whose only job is the number.
Order the radon test the same day you book the home inspection. The 48-hour minimum plus reporting means a late order is how people end up waiving the issue or extending contingencies. What you get: closed-house protocol, a continuous monitor with hourly logging (tamper-evident, which matters when the seller still lives there), and a written report your attorney can attach to a repair request. If it's high, you're not walking away from the house: you're negotiating a $1,500 to $2,500 fix from the strong side of the table. See radon mitigation system installation
Test before you list. If you're under 4.0, that report is a shield: it sits in your disclosure packet and takes the whole topic off the table. If you're over, you fix it on your schedule, with your choice of contractor, at market price, instead of during attorney review with a deadline discount. A documented system plus a passing retest reads as a maintained home, not a problem home.
You already know the failure mode: the test that got ordered on day 8 of a 10-day window. We hold priority slots for transaction testing across Plymouth, Kingston, Duxbury, and Marshfield, monitors placed within a day or two of the call, results within 48 hours of pickup. One fewer thing between your client and the closing table.
Closed-house conditions for 12 hours prior and throughout. Monitor placement per EPA transaction protocol. Hourly data logging that shows exactly when a door was propped or a monitor moved. A report that states conditions, duration, and result plainly. Nobody has to trust anybody: the data does the arguing.
Here's how the radon piece fits a standard Massachusetts purchase timeline, so you can see exactly where the pressure points are:
Offer accepted, Day 0. Your inspection contingency clock starts, typically 7 to 10 days.
Day 1-2: book everything at once. Home inspection and radon test ordered the same call. The radon monitor needs 48 hours in the house plus reporting time, so ordering it on day 6 of a 10-day window is how buyers end up choosing between waiving the issue and begging for an extension.
Day 2-3: monitor placed. Closed-house conditions begin 12 hours before it starts logging. The seller keeps living normally; the hourly log keeps the conditions honest.
Day 4-5: monitor out, report in. Written result within 48 hours of pickup, usually faster for transactions.
Day 5-7: decision window. Under 4.0: attach the report, contingency satisfied, done. Over 4.0: your agent requests mitigation or a credit, with a real installed price ($1,200 to $2,500) attached to the ask instead of a scary unknown.
Before closing: if the seller mitigates, the post-installation retest is your proof it worked. If you took a credit, you schedule the install for the week after you get keys and pocket the difference between the credit and the quote more often than not.
Seller installs before closing, retest attached: cleanest on paper, but you inherit the contractor the seller chose under deadline pressure, at the price they could get fastest. Insist on seeing the retest number, not just an invoice.
Credit at closing (usually the smart play): you control the contractor, the timeline, and the system quality, and credits are commonly negotiated at or above the actual install cost. The house closes on schedule.
Price reduction: functionally a credit with different paperwork; your attorney will have a preference based on your financing.
What you don't do is walk away over a radon number alone. In this county, with this geology, a high test is a Tuesday, and the fix is a line item, not a mystery.
A passing report in the disclosure packet removes a contingency risk from every offer you receive, and removed risk shows up in offer strength. A failed pre-list test that you fix on your own timeline turns into "new radon mitigation system with documented retest" on the feature sheet. Either branch beats the third option, which is finding out what your house tests at from the buyer's inspector, on the buyer's schedule, with the buyer holding the stronger hand.
$200 – $300
per transaction test
Usually within one to two business days across the county. Tell us your inspection deadline when you call and we work backward from it.
Almost never. Mitigation is a routine, priced, one-day fix. High tests become credits or seller-paid installs every week in this county. What kills deals is discovering the number late.
A recent protocol-compliant test with logged data generally satisfies both sides. An old charcoal-kit result from a drawer generally doesn't. When in doubt, retest: it's $200 against a $700,000 decision.
Yes. Normal living is fine; the protocol restricts windows, doors, and tampering, and the hourly log keeps everyone honest.
Radon Mitigation for Plymouth and Plymouth County. Test it. Fix it. Prove it's fixed.
(508) 503-6186