Tell someone or document it before you close it up.
I already hung the wrong size duct or installed from the wrong pile
Stop the run and document the mismatch. Do not keep connecting more wrong duct. Compare the installed piece to the print/shop tag and ask how to remove, adjust, or report it.
Do not keep building the run hoping the next fitting makes it work.
Check
Stop adding more pieces.
Photograph installed duct, tag/label if present, and drawing callout.
Measure actual installed size and correct required size.
Check if nearby staged material is mixed.
Ask foreman before removing or modifying.
Steps
Stop adding more pieces.
Photograph installed duct, tag/label if present, and drawing callout.
Measure actual installed size and correct required size.
Check if nearby staged material is mixed.
Ask foreman before removing or modifying.
Say this to your foreman
I installed [actual size] at [location], but the drawing/shop shows [required size]. I stopped and documented it. Do you want me to remove it, hold for review, or check staging first?