Patch Plate Sizing for Duct Modifications
When duct modified in field, patch plates cover cutouts. Wrong size or attachment creates leaks.
Stop if
- Minimum overlap required for this patch plate? What screw spacing?
Watch out
- Don't use patch smaller than opening. Don't rely on tape or mastic alone. Don't skip screws at corners and edges.
Check
- Patch at least 2 inches larger than opening on all sides?
- Screws spaced per SMACNA?
- Joint sealed?
Steps
- Patch at least 2 inches larger than opening on all sides?
- Screws spaced per SMACNA?
- Joint sealed?
Say this to your foreman
Minimum overlap required for this patch plate? What screw spacing?
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