Final inspections and tests (energy, blower-door, mechanical)

Code-required tests

The Seattle Energy Code requires two performance tests before occupancy on most addition + alteration projects:

• Blower-door test — measures whole-house or addition air leakage at 50 Pa pressure differential. Sets a maximum air-changes-per-hour (ACH50) target. A third-party tester runs the test.
• Duct leakage test — required when ducts run through unconditioned space. Measures total or leakage-to-outside duct loss.

Both tests produce a one-page report. Pass results go to the inspector; fail results trigger air-sealing or duct-sealing work and a re-test.

Final inspections by trade

Each sub-permit gets a final inspection separate from the building permit's final:

• Final electrical — all devices working, panel labels correct, smoke/CO detectors tested, GFCI/AFCI verified, kitchen circuits energized.
• Final plumbing — all fixtures connected, no leaks, gas pressure test, drain function.
• Final mechanical — equipment running, ducts balanced, ventilation airflow verified, range hood vented properly.
• Final building — all life-safety items verified, exit paths, smoke/CO functional, stairs and railings code-compliant.

Sequence and scheduling

The trades typically go first (electrical, plumbing, mechanical, then energy testing), then building. The building inspector signs off last because they want to see everything else has passed.

Each inspector is a separate appointment. The GC's project manager coordinates — typically 1–2 weeks of inspections at the end of construction.

What a failed inspection looks like

Most projects have at least one failed inspection on at least one trade. It's not unusual; it's how the system works. Common failures:

• A missing GFCI in a kitchen island outlet.
• A bathroom fan that didn't get connected to a switch.
• A smoke detector that wasn't replaced when the code changed.
• A railing baluster spacing that's 4-1/8" instead of <4".

Each fix is small. The trade comes back, fixes the item, calls for re-inspection. Each re-inspection is a few days of delay, not weeks.

When this is done

When every sub-permit and the building permit have a passed final inspection. SDCI issues the Certificate of Occupancy (CofO) — your signal to move back in.