Confirm whether this is grease duct, kitchen exhaust, lab exhaust, industrial exhaust, or normal exhaust.
Check the approved drawings/spec/submittal.
Look for cleanout/access, clearance, enclosure/wrap, weld/seal, slope/drainage, and inspection requirements.
Flag low spots, wrong slope, trap points, or drainage questions for the foreman before closing the run.
Ask foreman
In Grease Duct, Kitchen Exhaust & Industrial Exhaust, I’m looking at: What do I do when condensate/chemical exhaust slope or drain missed? What should I verify before I cut, drill, seal, cover, move, or install?