Where slate roofs usually leak
- Missing or cracked slates: water gets through the gap and onto the wood underneath.
- Flashing: metal around chimneys, in valleys and along walls wears out long before the slate does.
- Ridges and hips: the slates or metal caps along the top of the roof can come loose.
- Old patches: tar or caulk smeared over slate traps water and hides what is really going on.
- Gutters: clogged gutters can back water up under the bottom rows of slate.
What restoration means
Restoration keeps your good slate on the roof and fixes everything that has worn out around it. That can mean replacing a large number of broken slates, taking up a section and re-laying it on repaired wood, replacing flashing in valleys and around chimneys, and cleaning off years of tar patches. Because quality slate can outlast several sets of nails and flashing, restoring the roof is often far cheaper than replacing it.
Related: flashing and chimney work and repair or replace a slate roof.