Missing mastic at flange corner
Flange corners need a deliberate pass. Missing mastic at one corner can be enough to fail the joint.
Watch out
- Do not assume the corner got sealed because the straight flange did.
Check
- Check each flange corner one by one.
- Look behind/above the joint, not just front.
- Clean the corner.
- Apply approved seal method.
- Recheck before insulation or ceiling tile.
Steps
- Check each flange corner one by one.
- Look behind/above the joint, not just front.
- Clean the corner.
- Apply approved seal method.
- Recheck before insulation or ceiling tile.
Say this to your foreman
This flange corner looks missed. Do you want me to seal/check all four corners before cover?
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