Testing adjusting and balancing (TAB) is the three-phase procedural process applied to commercial HVAC systems on every closeout. Testing adjusting and balancing under ASHRAE Standard 111 brings measured field performance into compliance with the engineer’s design intent and produces the stamped report owners need at substantial completion.
The three phases of testing adjusting and balancing
First, testing captures the as-found performance of every device on the system — diffusers, return grilles, VAV boxes, coils, pumps, and fans. Then adjusting moves dampers, balancing valves, VAV setpoints, and fan curves to bring measured performance toward design. Finally, balancing equalizes flows across the system as a whole, and the team re-tests every device to confirm the adjustments held.
Why testing adjusting and balancing matters at closeout
Specifically, most owner-architect-contractor contracts require a TAB report before substantial completion. Most AHJs will not issue a CofO without it. Furthermore, the warranty year starts with documented baselines instead of guesswork, which protects every party against future disputes.
What a testing adjusting and balancing engagement looks like
Additionally, every testing adjusting and balancing engagement opens with a drawing review, mobilizes after mechanical start-up, and closes with a stamped report delivered to the owner’s rep with copies to the engineer and mechanical contractor per the spec.
Talk to us about a testing adjusting and balancing scope
Send the mechanical drawings and a schedule outline. You will hear back within one business day with a fixed-price proposal.
Request a proposal Call 800-883-6040
Related reading
Want the full picture? See our pillar page on our TAB services.
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