/ Field knowledge · IMC 608
Scheduled CFM is not installed performance.
IMC 608: scheduled CFM is not proof. The installed system has to be adjustable and balanced by an approved method. A generic “balance the system” note with no terminal values is the comment.
Educational 2024 IMC 608. Confirm adopted edition and the specified TAB procedure. This is not a TAB report.
- Permit chain: Chapter 4 required airflow → scheduled design airflow → installed adjustment means → approved balancing method → final measured airflow → documented correction of deficiencies.
- Show supply, return, outdoor, relief, and exhaust quantities. Provide accessible balancing dampers or other adjustment means.
- Final report: design, preliminary, and final readings, operating mode, fan speed, unresolved deficiencies.
Dampers above a closed ceiling
Do a pre-TAB walk before ceilings close: device access, damper position, filter condition, fan rotation, control mode, every test point reachable. Hidden devices are not a balancing method.
Source: DCT 608 · outlets: 603.18 · construction: 603 · smoke: 606.
What to send
The air schedule, whether TAB is specified, and photos if the ceiling is already closed over the dampers.
If the only note is “balance the system”
Send the M-601. Masterbuild will say whether 608 can even be proven — or the terminals were never scheduled.
Send Project Background+1 (786) 398-6940 · osmany.portal@masterbuildconsulting.com
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