“How long has this roof got left?” is one of the questions we hear most. Buyers want to know before they commit. Owners want to know whether to repair or replace. Landlords want to plan their spending.
There’s no exact answer for any single roof. But there are typical lifespans for each material, and there are clear signs when a roof is getting near the end. This guide sets them out, and explains why the parts you can’t see, such as nails, battens and underlay, often decide the real answer.
Typical lifespans at a glance
These are rough guides from published sources. Many roofs last longer, and some fail much sooner. A well-laid roof that’s been looked after will usually beat the average, and a roof that was poorly fixed or never maintained will fall short of it.
| Roof type | Often lasts | What usually fails first |
|---|---|---|
| Natural slate | 100 years or more (Checkatrade) | Nails, battens and underlay |
| Clay tiles | commonly 50+ years | Fixings, ridge bedding, underlay |
| Concrete tiles | commonly 50+ years | Surface wear, ridge bedding, underlay |
| Felt flat roof | around 15–20 years (Checkatrade) | Surface, laps and upstands |
| EPDM rubber | around 30–50 years | Seams and details |
| GRP fibreglass | up to about 30 years | Joints, edges and top coat |
Slate: the slates outlast the nails
Good natural slate is very durable, and many London terraces still have their original Welsh slate. The trouble is usually what holds it on. Over the decades, the nails corrode. When a nail gives way, the slate slides down the roof. This is often called “nail fatigue”.
One or two slipped slates may be a one-off. A growing number of slipped slates spread across a roof can mean the nails are failing widely, and patching will only go so far. Our guide to slipped slates and nail fatigue explains what to look for.
Clay and concrete tiles
Clay tiles, including the handmade tiles and Kent peg tiles found across the Weald, can last a long time. Peg tiles are held by pegs through two holes, and those pegs and the battens can decay before the tiles do. Frost can also cause older clay tiles to flake.
Concrete interlocking tiles are common on post-war homes, including in new towns such as Crawley, Harlow, Stevenage and Basildon. Over time the surface wears and the tiles become more porous and brittle. The ridge and verge mortar often needs attention before the tiles themselves. See our guides to clay tiles and concrete tile roofs.
Want a roof surveyed? We cover London and the South East, with written reports and photos from £150 including VAT. Book a survey or call 07833 053749.
Underlay and battens
Under most pitched roofs is a layer of underlay, a second line of defence against wind-driven rain. Breathable roofing membranes appeared in the UK in the late 1990s. Older roofs often have bitumen felt, which can become brittle and tear, especially near the eaves. Very old roofs may have no underlay at all.
That isn’t automatically a problem, but it means the slates or tiles have to do all the work. Battens can also rot where water has been getting past for years, which loosens the fixings even when the slates themselves are sound. From the loft, where there’s safe access, we can usually see the underlay, the battens and any signs of water getting past the coverings.
Flat roofs age faster
Flat roofs generally have shorter lives than pitched ones, and the material makes a big difference. A felt roof that’s 20 years old and showing splits is at a different stage from an EPDM roof of the same age. Poor drainage, foot traffic and bad details at upstands and outlets all shorten a flat roof’s life. Our guide to flat roof problems covers the faults to watch for.
Flat roofs on extensions, dormers and garages are often of a different age from the main roof. It’s common for a house to have a pitched roof in fair condition and a flat roof at the back that’s nearing the end, or the other way round. Each one needs judging on its own.
Signs a roof is near the end
- Slipped or missing slates or tiles spread across the roof, not just in one spot.
- Repeated patch repairs, or a coating painted over the whole roof.
- Daylight visible through the coverings from the loft.
- Torn or sagging underlay, or water staining on timbers.
- A dipping ridge or a roof slope that’s visibly uneven.
- On flat roofs, widespread cracking, many blisters or leaks that keep coming back.
Any one of these on its own may be fixable. Several together suggest it’s time to look at the whole roof.
Safe checks you can do yourself are limited to looking from the ground, from windows and, carefully, from inside the loft. Binoculars help. Never climb onto the roof to look. If you spot something, a few photographs are a good starting point when you get in touch.
Why age alone isn’t the answer
A slate roof that’s 90 years old can be in better condition than a concrete tile roof half its age. What matters is the condition of the coverings, fixings, flashings and underlay today, and how well water is getting off the roof.
That’s what a roof survey looks at. We don’t give a “life expectancy” figure, because that would be a guess. Instead, the report sets out the condition of each part, with photographs, and written recommendations prioritised by urgency where relevant. Landlords and block managers can use a landlord roof survey to plan work over several years. Buyers often want the same information before exchange, through a pre-purchase roof survey.
If your home is listed or in a conservation area, replacing a roof in different materials may need permission. Check with your local council and Historic England. For a survey, contact us.
Quick answers
How long does a slate roof last?
Natural slate can last 100 years or more, according to Checkatrade. The nails, battens and underlay often fail first.
How long do concrete roof tiles last?
Commonly 50 years or more. The surface wears over time, and ridge mortar often needs attention sooner.
Can you tell me how many years my roof has left?
We don’t give a life expectancy figure. The report sets out the condition of each part and what needs attention.
Is it worth repairing an old slate roof?
Often, if the problems are local. Widespread slipping across the roof can point to wider nail failure.
Related services
More advice
- Slipped Slates and Nail Fatigue Explained
- Concrete Tile Roofs: Lifespan and Common Faults
- Clay Tiles, Kent Peg Tiles and Tile-Hanging
- Flat Roof Problems: Ponding, Blisters and Splits
- All advice
This guide is general information about roofs and roof surveys. It isn’t legal, insurance or structural engineering advice; for those, speak to a suitably qualified professional.