Buyer playbook: Order a professional short-term test early in the inspection window, keep closed-house conditions, and decide thresholds in writing (commonly ≥ 4.0 pCi/L) before emotions run the negotiation.
Who usually pays
Local custom varies. Buyers frequently order and pay for the test as part of due diligence. Sellers sometimes pre-test and disclose. Either way, insist on protocol-compliant placement and a written report with device serials and timestamps when possible.
Timelines
Continuous monitors often run about 48 hours under closed-house conditions. Charcoal kits may need several days plus lab turnaround. Build this into your inspection period—don’t squeeze it into the last 24 hours.
If the result is high
- Request seller-paid mitigation by a qualified installer
- Or a closing credit based on realistic Black Hills system pricing
- Require post-mitigation testing for verification
- Confirm fan location, exterior aesthetics, and interior pipe routing in writing
See cost ranges and real estate testing.
Existing systems
A manometer in the green does not replace a recent air test. Fans fail. Pipes crack. Ask for the original install paperwork and schedule verification testing.
Need a local next step? Call (605) 600-6282 to talk through testing, real estate timing, or mitigation for your Rapid City–area home.