Design intent is a starting point, not a guarantee
Duct and pipe networks behave differently in the field than on paper. Fittings get relocated around structure, dampers are left at installation defaults, and pumps run against a system curve nobody has verified. The result is a building that meets its drawings but not its design intent.
What the TAB process actually covers
Testing establishes what the system is doing now: airflow at each terminal, water flow through each coil, static pressure across filters and fans, motor current draw. Adjusting brings those values to design by setting dampers, valves, pulleys and drive frequencies. Balancing distributes the total proportionally so no zone is starved while another is over-served.
Where the value shows up
Occupant complaints fall because rooms hold their setpoints. Energy consumption drops because fans and pumps stop fighting throttled dampers. Equipment life extends because motors run inside their design envelope. And the commissioning authority gets measured evidence instead of assurances.
When to programme it
TAB needs the system substantially complete, ceilings accessible and controls responding. Scheduling it too early means re-work; too late means findings arrive after the handover date. The practical window opens once installation is finished and closes before final commissioning and client witnessing.
