What do I do if I think this duct should be TDC/Ductmate instead of S-and-drive?

Stop and verify the connector callout. Pressure class, duct size, leakage class, and project specs decide the joint system - not what material happens to be nearby.

Verify the required connector type before adapting anything. S-and-drive versus flanged duct is a drawing/spec/shop-standard call, not a habit call.

Rectangular Duct & Fittings 2nd Year YELLOW

Stop if

Ask any time the field material and drawing/spec connector type do not match.

Watch out

Do not mix connector systems in the field without approval.

Check

Check the piece mark
Check the approved connection detail
Verify both duct ends are meant to connect

Steps

Check the shop drawing/detail.
Look for connector callouts on the duct schedule.
Compare delivered material to the detail.
Photograph the duct ends.
Ask before substituting one connector system for another.

Say this to your foreman

In Rectangular Duct Assembly: S-and-Drive, I'm looking at: What do I do if I think this duct should be TDC/Ductmate instead of S-and-drive? What should I verify before I cut, drill, seal, cover, move, or install?