What the problem is
Radon shows up in a home sale under time pressure and with money attached. Buyers want certainty, sellers want the deal to close, and both are working inside a short inspection window. The wrong test method — a mail-in kit with a lab turnaround, or a test run with windows open — can burn the window entirely and leave both parties negotiating from uncertainty.
How to know if you need it
- You are under contract and the inspection period is running.
- The home has an existing mitigation system and the buyer wants proof it works.
- You are listing a home and want a result in hand before offers arrive.
- The general home inspector flagged radon as a recommended additional test.
How the test is performed for a transaction
- 1A continuous radon monitor is used, not a passive kit — it logs hourly and records movement or tampering.
- 2Closed-house conditions begin 12 hours before deployment; the listing agent and occupants are notified in writing.
- 3The device is placed on the lowest lived-in level following standard placement rules.
- 4The measurement runs a full 48 hours.
- 5A written report with hourly data, average concentration, and test conditions is issued the day the monitor is retrieved.
Timeline inside an inspection period
Radon timeline inside a home sale
Typical scheduling. Actual dates depend on contractor availability and your contract terms.
Order the radon test at the same time as the general home inspection. Closed-house conditions start 12 hours before the device is placed.
What the result means for the deal
| Result | Common outcome |
|---|---|
| Below 2.0 pCi/L | Documented and closed out; no action |
| 2.0 – 3.9 pCi/L | Disclosure; mitigation is optional and often negotiated |
| 4.0 pCi/L or above | Buyer typically requests mitigation, a credit, or a price adjustment |
Mitigation during a transaction is usually a one-day installation, which is why an elevated result rarely needs to delay a closing when it is caught early in the inspection period. Post-mitigation verification adds roughly three more days.
What affects the cost
- Continuous monitor deployment and retrieval (two trips).
- Number of monitors for large or multi-foundation homes.
- Rush scheduling inside a tight inspection window.
- Whether post-mitigation verification is also required before closing.
What happens after the test
Both parties get the same documented report. If mitigation is agreed to, the paperwork chain buyers and lenders actually want is the pre-mitigation test, the system description, and the post-mitigation verification result. We provide all three, and the report is written to be read by someone who has never thought about radon before.
Common questions
There is no rule — it is negotiated. Buyers commonly pay for the test as part of due diligence, and mitigation is often handled by the seller or through a credit. Both approaches are normal in the Albuquerque market.
Related services
Keep learning
- Buying a Home With Radon: A Buyer's GuideAn elevated radon result is one of the most fixable findings in a home inspection. Handled early, it rarely threatens a closing.
- Selling a Home With Radon: A Seller's GuideRadon discovered during a buyer's inspection is a negotiation. Radon discovered before you list is a line item you control.
- Radon Testing Methods ComparedEvery radon test measures the same thing, but the method determines how much you can trust the number and what decisions it can support.