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

Code-required tests (WSEC 2021)

WSEC 2021 requires performance tests before occupancy on most addition + alteration projects:

• Blower-door test — measures whole-house or addition air leakage at 50 Pa pressure differential. A third-party tester runs the test and produces a one-page report.
• Duct leakage test — required when ducts run through unconditioned space. Measures total duct leakage or leakage-to-outside.

WSU Energy Program publishes the required compliance forms including the Building Air Leakage Test Results form and Duct Leakage Affidavit. Pass results go to the Renton CED inspector; fail results trigger air-sealing or duct-sealing work and a re-test. Ask Renton CED at permit issuance whether a third-party energy rater certification is required or whether the contractor's signed WSEC compliance forms suffice.

Final inspections by trade

Each sub-permit gets a separate final inspection:

• Final electrical — City of Renton inspector. 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.
• Final mechanical — equipment running, ducts balanced, ventilation airflow verified, range hood vented.
• Final building — life-safety items, exit paths, smoke/CO functional, stairs and railings code-compliant.

Sequence

The trades go first (electrical, plumbing, mechanical, energy testing), then building. The building inspector signs off last.

What a failed inspection looks like

Most projects fail at least one inspection on at least one trade. Common items: missing GFCI in a kitchen island outlet, a bathroom fan not connected to a switch, a railing baluster spacing slightly over code. Each fix is small; re-inspection is a few days, not weeks.