Slate Roof Valley Repair
A valley is where two roof slopes meet. It carries more water than any other part of the roof. On slate roofs, the metal valley liner often wears out before the slate beside it.
Signs you might notice
- Leaks where two roof planes meet
- Rust, holes or tar patches in the valley metal
- Debris piling up in the valley
- Slates along the valley edge cracked or slipping
Common causes
- Valley metal worn thin or pinholed with age
- Debris holding water against the metal
- Ice backing up in winter
- Slate cut too tight or loose along the valley
What a slate professional should check
- 1.Type of valley: open metal or closed/woven
- 2.Metal condition along the full length
- 3.Slate along both edges of the valley
- 4.Where the valley drains into gutters
Repair options
Valley repair often means removing slate along both sides, installing new metal (often copper), and relaying the slate. Short spot patches may help briefly but do not address worn metal along the whole run.
Final scope depends on an in-person assessment. Nothing on this page is a diagnosis of your roof.
Questions homeowners ask
- Can a valley be patched instead of replaced?
- Small holes are sometimes patched, but if the metal is worn along its length, replacing the liner is usually the lasting option.