You’ve submitted your drawings, paid your fees, and waited for review. The jurisdiction sends back a comment: “Provide mechanical engineer’s response to IMC Section 603.9” or “Energy compliance documentation does not match equipment schedule — revise and resubmit.” For a GC managing a schedule, that comment is a gut-punch. But it is almost never a project-ending problem. It is a documentation and response problem.
Important distinction: A permit comment says “this doesn’t satisfy the code as submitted.” It does not say your building can’t be built. In almost every case, the path forward is a written PE response, revised drawings, or additional documentation — not a redesign.
Why Mechanical Comments Happen
Energy compliance documentation mismatch
COMcheck and REScheck reports that don’t match the equipment schedule, use the wrong energy code version, or are missing required sections are the most common source of mechanical permit comments.
Missing duct construction specifications
The IMC has specific requirements for duct materials, sealing, insulation, and support. When drawings don’t specify the duct construction standard, the reviewer calls it out.
Missing ventilation calculations
Commercial projects require documentation that the proposed system provides adequate outdoor air. Missing or incorrect ventilation calculations — based on ASHRAE 62.1 or the IMC — generate consistent comments.
Missing mechanical specifications
Drawings without equipment efficiency ratings, duct construction standards, or pipe material specs give the reviewer nothing to verify against code.
What a Good PE Response Looks Like
A permit comment response is a written document, signed by a licensed engineer, that addresses each comment point-by-point: quote the specific code section cited, explain how the project does or will comply, reference the revised drawing or calculation that demonstrates compliance. Clear, specific, and submitted with a complete revised package ready for re-review.
Kiddio Engineering Permit Comment Response Service
Fee: $250–$400. Turnaround prioritized — this is time-sensitive and is treated accordingly. When you receive mechanical or plumbing comments, contact Kiddio Engineering the same day. Every day the permit is held costs your client money.