Commissioning

A new office can have installed air conditioning that turns on yet fails to maintain the required temperature across all floors, so commissioning tests the system under defined conditions and records whether it meets requirements. Merely seeing equipment run is not enough.

The Whole Building Design Guide describes commissioning documents as a record of key project decisions and performance criteria across phases, emphasising owner requirements, team responsibilities, acceptance and use after occupancy, which supports a process broader than a single final inspection. Define the owner's requirements first, with temperature, ventilation, power resilience and maintenance needs made measurable, because otherwise the team has no clear acceptance target.

Set a commissioning plan listing systems, roles, tests, dependencies, timing and documentation that matches the project's actual scope. Review design by comparing drawings and specifications with owner requirements before installation, since a design error found early is easier to correct.

Coordinate disciplines, because controls, electrical equipment and mechanical systems interact and a test of one component alone may miss a failure when systems run together. Inspect installation to check that equipment, wiring, sensors and labels match approved specifications, since functional tests cannot cure missing parts, and use prefunctional checks to verify calibration, connections, safety settings and manufacturer start-up before demanding full performance.

Run functional tests of how a system responds to normal load, failure and changeover conditions where relevant, recording conditions and actual results. Consider life safety separately, because fire and emergency systems may have specific statutory inspections that commissioning work does not replace.

Document faults in an issue log naming the failure, location, owner and status, since a verbal promise to repair is not a closed test, and retest after correction, because a changed sensor or control program can fix one issue and create another. Check seasonal conditions too, as heating or cooling performance may not be testable under the weather at handover, so plan deferred tests and assign responsibility.

Train operators and deliver documentation, because a working system can fail in use if staff do not know alarms, schedules or maintenance needs, and as-built information, test results, manuals and settings help the facilities team operate the asset. Clarify acceptance, since the owner, contractor and commissioning provider may have different roles, and state who signs each document and what unresolved issues remain.

Budget time, because testing can reveal corrections that affect the schedule and a handover date should not erase critical open faults, and make sure operators have the passwords, permissions and instructions needed for lawful operation while keeping security-sensitive details protected. Separate commissioning from snagging, since a snag list can capture visible defects such as finishes while commissioning focuses on verified system performance, and both may be needed.

Avoid treating a pass rate as quality alone, because first-time pass rate shows testing outcomes but rushed or easy tests can inflate it, so review coverage and severity and track critical issues, where a minor label error differs from failure of emergency power. Include a post-occupancy review, know the contract because requirements, warranties and responsibility for defects depend on project documents and local rules, and measure owner outcomes such as energy use, comfort complaints and equipment reliability, which supplement rather than replace formal acceptance tests.