What are the types of metal roof flashing?
Short answer. Metal roofs use a family of trims and flashings, each for one transition: eave and rake trims at the edges, ridge and hip caps at the peaks, valley pans where slopes meet, sidewall and endwall flashing where the roof meets a wall, transition flashing at pitch changes, Z flashing and closures to seal panel ends, and flexible pipe boots and curb flashing at penetrations. Most are formed from the same coated steel or aluminum as the panels so the metals match.
Edges
- Eave trim or drip edge: carries water into the gutter and protects the deck edge.
- Rake or gable trim: covers the panel edge at the gable ends and resists wind uplift.
Peaks and slopes
- Ridge cap: covers the peak; vented versions work with profiled closures to ventilate the attic.
- Hip cap: covers hips, usually with closures underneath.
- Valley pan: a wide, often W-shaped pan where two slopes meet.
- Transition flashing: where the pitch changes, such as a steep main roof meeting a lower porch roof.
Walls
- Sidewall flashing: where the side of a panel runs along a wall.
- Endwall or headwall flashing: where the top of a slope meets a wall.
- Kickout flashing: where a roof edge meets a wall, diverting water into the gutter.
- Counterflashing: laps over base flashing at masonry, or tucks under siding.
Panel ends and seals
- Z flashing or Z closure: a Z-shaped strip used at endwalls, transitions and ridges to seal panel ends and give trims something to fasten to.
- Foam closures: profiled strips that fill the gaps under panel ribs at eaves and ridges.
Penetrations
- Flexible pipe boots with formable bases for vent pipes.
- Curb flashing for skylights, chimneys and equipment, often with a diverter on the uphill side.
Material rules
Use trims of the same metal and coating as the panels, keep copper and lead away from steel panels, and use fasteners with sealing washers suited to the panel. See metal roofing in Georgia and roof flashing explained.