Slate Roof Flashing Repair
Good slate can last far longer than the metal around it. Flashing is the metal that seals the joints where the roof meets walls, dormers, chimneys and pipes. When it wears out, water gets in even though the slate looks fine.
Signs you might notice
- Leaks along a wall, dormer side or skylight
- Tar, caulk or roof cement smeared over metal joints
- Rusted, split or lifted metal at roof edges
- Stains inside near where the roof meets a wall
Common causes
- Metal that has corroded or worn through with age
- Counter-flashing pulled out of mortar joints
- Step flashing that was reused or cut too short
- Surface patches that crack and hold water
What a slate professional should check
- 1.Step, counter, apron and wall flashing condition
- 2.Type of metal used and how it was attached
- 3.Signs of past patching with tar or sealant
- 4.Slate around the flashing that must be removed and reset
Repair options
Flashing repair on slate usually means carefully removing nearby slates, installing new metal, and resetting the same slate. Copper is commonly used for long life. Sealant alone is rarely a lasting fix.
Final scope depends on an in-person assessment. Nothing on this page is a diagnosis of your roof.
Questions homeowners ask
- Why would flashing fail before the slate?
- Many roofs used thinner metal or steel that wears faster than quality slate. The slate may have decades left while the metal is spent.
- Is roofing cement a good flashing repair?
- It may slow a leak for a short time, but it cracks, hides problems and can make proper repair harder later.