Rooftop Equipment Structural Review: Review Method

A review of rooftop equipment structural review: review method is not a second reading of every page. It tests a defined question: whether the record is complete, internally consistent, traceable to its sources, and suitable for the next project decision. Use the following evidence as the starting set: operating and seismic loads, curb geometry, framing, access, vibration, and waterproofing handoff; the governing code or AHJ checklist; current architectural and engineering backgrounds; assumptions that need confirmation; and a record of unresolved decisions.. Then state what would cause the reviewer to stop and request more information.

For this structural review, compare the current document against the source record, the coordinated drawing set, and the applicable authority or code instructions. Look for mismatched dimensions, stale schedules, unexplained assumptions, missing references, and changes that appear on one sheet but not another. A reviewer should be able to reproduce the conclusion from the cited evidence rather than infer it from a confident sentence.

• Identity and revision test: is this the current record?
• Completeness test: are the required inputs and attachments present?
• Consistency test: do related sheets, schedules, and calculations agree?
• Responsibility test: is the correct professional or authority answering?
• Exception test: are unresolved items and limitations visible?

A useful review finding says what is wrong, where it occurs, why it matters, and what evidence or revision would close it. For rooftop equipment structural review: review method, distinguish a missing input from a calculation error, a coordination conflict from an AHJ interpretation, and a formatting issue from a design change. Assign each finding to its owner and preserve the original reference so a later response can be checked.

The reviewer should issue a dated disposition: accepted, accepted with noted limitation, revise and return, or refer to another project participant. Link each disposition to the revised sheet, calculation, field record, or agency answer. This is quality control, not an approval promise; the AHJ and responsible engineer retain their own professional and regulatory decisions.

For rooftop equipment, the review follows one continuous load path. Start at the unit: the operating weight from the submittal — not the shipping weight — plus curb, rail, and isolation hardware. From there we confirm how that weight lands: spread across how many joists or beams, at what spacing, and whether the supporting members were sized for a concentrated load at that location or only for the uniform roof load. Anchorage is checked separately from gravity support: wind uplift and seismic forces try to move or overturn the unit, and the connection at the curb — not the unit's own weight — resists them. The review stops when any link in that chain is undocumented: an unknown unit weight, framing that cannot be identified from the drawings or field evidence, or a deteriorated deck that changes what the connections can hold.

• Operating weight, curb, and isolation hardware from the current submittal
• Joist and beam capacity under the actual point-load pattern
• Check uplift and seismic anchorage at the curb connection
• Deck and framing condition where the unit lands