01
Map every metal in the drainage path
Gutters, valleys, step flashings, fasteners, snow guards, HVAC components and masonry accessories may interact directly or through runoff. A compatible detail considers the whole roof, not one flashing in isolation.
02
Separate unlike materials where required
Dissimilar metals can create galvanic action in the presence of moisture. Suitable separation layers, compatible fasteners and drainage direction reduce risk, but the best solution is often a coordinated metal palette.
03
Account for movement
Long metal runs expand and contract. Seams, cleats and attachments should allow movement without tearing corners or stressing slate edges.
