Roofs rarely fail all at once. They give warnings for years, and reading them correctly can save you either a needless re-roof or a run of expensive repairs. Here is what we look for.
Signs you can see from the ground
- Many cracked, slipped or missing tiles spread across the roof, not just one patch.
- A sagging ridge or dip in the roof plane, which points to timber or batten failure.
- Heavy moss that lifts tiles and holds water against them through winter.
- Tiles that look pale, flaky or crumbling. Old concrete tiles lose their surface and become porous.
- Mortar missing from ridges, hips and verges.
Signs from inside the loft
- Daylight through the covering.
- Underlay that is torn, brittle or missing. Bitumen felt from before the 1990s perishes.
- Damp or dark staining on rafters in several places.
- Nail sickness on slate roofs: the slates are fine but the iron nails have rusted through, so slates slip one after another.
Signs from your bills
If you have paid for roof repairs in two or three of the last five winters, the roof is telling you something. Each repair is money that would otherwise go towards a replacement with a long guarantee.
How long roofs last
| Covering | Typical life |
|---|---|
| Concrete interlocking tiles | 40 – 60 years |
| Clay plain tiles | 60 – 100 years |
| Natural slate | 80 – 150 years (nails and battens fail first) |
| Felt flat roof | 10 – 20 years |
| EPDM or GRP flat roof | 25 – 50 years |
The covering often outlasts what is beneath it. Many slate roofs are re-laid using the original slates on new battens and membrane.
Not sure which side of the line your roof is on? A free survey with photographs gives you an honest answer and a written price for both options.