What belongs in a mechanical submittal package
Division 23 packages are usually broken into equipment, distribution, and controls. A typical breakdown:
- 23 05 48 / 23 05 93 — Vibration isolation and TAB (test-and-balance is often a deferred submittal)
- 23 07 13 — Duct and pipe insulation with thickness schedules
- 23 31 13 — Metal ducts: gauge schedule, sealant class, and coordinated shop drawings
- 23 34 00 — Fans: curves with the operating point plotted
- 23 36 00 — VAV terminal units: sizes, min/max CFM matched to the schedule
- 23 73 13 / 23 74 13 — AHUs and RTUs: capacities, ESP, electrical data (MCA/MOCP), curb and clearance dimensions
- 23 09 00 — Controls: sequences of operation, points list, valve and damper schedules, panel layouts
Equipment data the engineer actually checks
Mechanical engineers review against the schedule, line by line: total and sensible cooling capacity, heating input/output, airflow, external static pressure, electrical characteristics, and sound data where specified. Submit the selection at the scheduled conditions — a generic catalog page at ARI conditions will bounce. Include unit dimensions and weights, because the structural engineer may need to confirm curb loads, and note any accessories (economizers, hail guards, convenience outlets) that appear in the spec.
Ductwork is a shop-drawing exercise, not a cut-sheet exercise: fabrication drawings showing gauge, seal class, hangers, and routing coordinated with the other trades, typically at 3/8" scale or in a BIM-derived format on larger jobs.
The review round-trip
The package routes through the GC to the mechanical engineer of record. Equipment packages commonly take the full review window because the engineer is verifying selections against loads; controls submittals often take longer and generate the most comments, since sequences touch every other system. Plan on at least one 'Revise and Resubmit' cycle for controls, and hold ductwork fabrication until the equipment connections are approved — duct shop drawings drawn to a rejected AHU are wasted work.
Common rejection reasons on HVAC submittals
The recurring offenders:
- Capacity or ESP below scheduled values, or selections run at non-scheduled conditions
- Electrical data that conflicts with the electrical drawings (MCA/MOCP vs. breaker and feeder sizes)
- Missing sound data when the spec sets NC or dBA limits
- Substituted equipment that changes physical dimensions without confirming it still fits the mechanical room or curb
- Controls submittal missing sequences or points lists — cut sheets for thermostats alone don't cut it
- No seismic or wind restraint calculations where the code requires them
How Submittal.App builds the mechanical package
Feed Submittal.App the equipment schedule or spec sections and the AI Builder matches each scheduled unit to manufacturer data, assembles the package with cover sheet, table of contents, and per-section dividers, and keeps every catalog number tied to its schedule tag. Review comments come back through a shared link, and the approved package rolls into procurement — quotes and POs generated from the same data, no retyping.