Confirm the exact location from approved drawings and field marks.
Check what is above, below, behind, or inside the cut.
Verify whether the wall/deck/roof/shaft/beam is structural, rated, waterproofed, post-tensioned, or shared with other trades.
Ask foreman
In Cutting, Holes, Penetrations & Field Fabrication, I’m looking at: What do I do when rectangular duct cut weakens reinforcement/seam? What should I verify before I cut, drill, seal, cover, move, or install?
Do not
Do not cut because the duct does not fit.
Why it matters
Approved drawings/specs; structural drawings; GC/foreman/safety approval; sleeve/firestop/waterproofing details; local code/AHJ
