Commissioning and Verification Sign-Off on a Small Commercial Building
A 45,000 ft² new mixed-use building (retail + office) is at final inspection. The mechanical scope includes two 40-ton chillers, VAV air handlers, a building automation system (BAS), and a service water heating system with a gas-fired boiler and recirculation loop. The owner's rep submits a commissioning report that covers only the chillers and air handlers; the BAS and service water heating are listed as 'verified by contractor startup sheet.' The inspector also finds the duct leakage test report missing and the economizer dampers on one AHU stuck closed. The certificate of occupancy is requested.
1. Given the building size and systems, what commissioning documentation should the inspector expect, and is the submitted report adequate?
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The building exceeds the size threshold (typically 25,000 ft² conditioned) and includes complex systems (multiple chillers, VAV, BAS), so commissioning is required and must cover the systems listed in the code's commissioning scope - including HVAC controls/BAS and service water heating, not just chillers and AHUs.
The submitted report is inadequate because:
- BAS and SWH are excluded and merely 'contractor-verified' - startup sheets are not commissioning.
- No functional performance testing of controls sequences, economizer operation, or SWH recirculation/temperature control.
- No commissioning report signed by the commissioning authority covering all required systems.
The inspector should not accept the report as satisfying commissioning and should require a complete report before final sign-off.
2. How should the stuck economizer damper and missing duct leakage report affect the sign-off decision?
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Both are verification failures that independently block sign-off:
- Economizer damper stuck closed: a functional failure of a required energy feature. It must be repaired and functionally tested (damper stroke, actuator, changeover, linkage) with results documented. A stuck damper means the economizer cannot deliver its intended savings and may indicate broader controls deficiencies.
- Missing duct leakage test: where the code requires duct leakage testing (e.g., ducts outside conditioned space), the report is a required compliance document. Its absence means compliance is unverified; the inspector should require the test and passing results.
The inspector should issue a punch list / correction notice citing these items, require retest documentation, and withhold the certificate of occupancy until corrected and verified. Final sign-off is conditioned on documented correction, not on the owner's assurance.