A TAB report is the closeout deliverable that proves the mechanical system performs to design. Owners, engineers, AHJs, and operators all read it for different reasons. Here is what the document contains and what each section is for.
What the TAB report contains
Every TAB report we deliver opens with the project metadata — owner, GC, mechanical contractor, system tag, certified balancer signature — and proceeds through air-side and water-side data sheets. Specifically, supply CFM at every diffuser is measured against design and recorded with the instrument used, the date, and the certified technician. Furthermore, hydronic GPM at every coil is recorded the same way.
Why the TAB report matters at closeout
Therefore the TAB report is the document the AHJ asks for, the document the engineer signs off against, and the document that becomes the operations baseline for the warranty year. Additionally, lenders and certifying bodies (LEED, ENERGY STAR, WELL) ask for the TAB report whenever the building changes hands.
What inspectors actually look for
AHJ plan reviewers and field inspectors check three things in particular. First, the certified stamp — every certifying body publishes a public registry; inspectors verify the technician is currently active. Second, the data sheets — measured values must be present for every device named in the spec; missing rows trigger an immediate rejection. Third, the deficiency log — inspectors expect a list of any device that didn’t meet design, with the reason and the corrective action. A clean document that hides deficiencies invites suspicion; an honest document that flags deficiencies and tracks corrections gets approved on first review.
Frequently asked questions
How long is a typical TAB report?
A TAB report on a mid-size commercial building runs 40-120 pages. The TAB report depth scales with system complexity and device count.
Who stamps the TAB report?
A certified TAB technician (NEBB or AABC). The TAB report without the stamp is a draft, not a deliverable.
How long does the TAB report take after field work?
Typically 1-2 weeks. The TAB report production includes review by the certified balancer and a sanity check against design before release.
How modern documentation has evolved
Twenty years ago, every closeout document was a paper binder. Today, most are PDFs with bookmarks, hyperlinks to system tags, and digital signatures from certified technicians. ASHRAE Guideline 4 covers preparation of operating and maintenance documentation. Many lenders and certifying bodies now accept BIM-linked deliverables where each system tag references the corresponding measurement data. The trend is toward longer document lifecycles — the same closeout deliverable serves the warranty year, the first refinance, the first major retrofit, and the eventual sale. Owners benefit when documentation is structured for that long horizon from day one.
Standards behind the documentation
ASHRAE Standard 202 establishes the framework for measurement and verification on commercial buildings. ASHRAE Guideline 4 covers the preparation of operations and maintenance documentation. IBPSA building performance simulation standards inform how baselines are constructed for long-term tracking. LEED v4 and v4.1 require documented verification on the Enhanced Commissioning credit. Most state energy codes reference these standards by name. The cumulative effect: closeout documentation has become its own discipline, with its own quality bar — and AHJs increasingly enforce that bar at field inspection.
Related reading
Want the full picture? See our pillar page on commercial air balancing.
