Signs your roof has reached the end of its life
Natural slate itself can last a very long time, but the nails holding it rust through, so slates start sliding out one after another. Older concrete tiles turn porous and spall in the frost, and the bitumen underfelt found on many 1960s and 70s houses rots away at the eaves. When those problems are spread across the whole roof, repairs just move the leak somewhere else.
- Nail sickness: slates slipping in several places at once
- Concrete tiles that are flaking, porous or covered in moss
- Underfelt that has perished and hangs loose at the eaves
- A visible dip or sag along the ridge or rafters

