Metal Roofing Inspection

Metal panels must be straight, properly overlapped, with correct fastener placement. Panels must allow for thermal expansion.

1. Sight along panel edges — should be straight with no waviness (oil-canning)

2. Check panel overlap direction — should be away from prevailing wind

3. Verify screw placement — on ribs/high points for exposed fastener panels, at proper spacing

4. Check that rubber gaskets on screws are not over-compressed or under-tightened

5. Verify panels overhang eave by 1-2" (water drips into gutter)

6. Check end laps — minimum 6" overlap, sealant between

7. Verify ridge cap is properly installed and sealed

- Oil-canning (waviness in flat areas — cosmetic but common complaint)

- Screws over-driven (compresses gasket, causes leaks)

- Screws under-driven (gasket doesn't seal)

- Wrong overlap direction (wind drives rain under panels)

- Missing sealant at end laps

- Panels not aligned (visible from ground)

Flashing critical at all transitions: ridge, eave, rake, valleys, walls, and penetrations. Use matching metal or approved sealant.

1. Check ridge cap — continuous, properly overlapped and sealed

2. Verify eave drip edge — extends into gutter

3. Check rake (side) trim — properly fastened and sealed

4. Inspect valley treatment — valley flashing or woven panels

5. Check wall-to-roof transitions — step flashing or continuous counter-flashing

6. Verify all penetrations (vents, pipes) have proper boot or flashing

7. Check for proper underlayment (synthetic or ice & water shield in cold climates)

- Missing ridge sealant (wind-driven rain enters)

- No drip edge at eave

- Wall flashing poorly sealed

- Pipe boot missing or wrong size

- No underlayment (condensation drips into attic)

- Valley flashing too narrow