The short answer
In MyBuilder's slate roof guide (updated 21/08/2026), natural slate laid properly is given 80 to 100 years or more, Welsh stone is said to pass a century as a matter of course, and Spanish slate is put at 75 to 100 years. Fibre-cement slate gets 30 to 50 years. Treat all of these as typical ranges and not as promises, because the nails, battens and leadwork tend to tire first.
Lifespans by type of slate
Published figures differ, so it helps to see them side by side. Each is a typical range, shaped by how exposed the roof is, how well it was laid and what upkeep it has had since. None of them is a promise. Where two sources disagree we have shown both rather than picking the kinder number.
| Covering | Typical life | Source |
|---|---|---|
| Welsh slate | Passes a century as a rule | MyBuilder, 21/08/2026 |
| Spanish slate | 75 to 100 years | MyBuilder, 21/08/2026 |
| Natural slate, well maintained | 100 years or more | CORC |
| Natural slate, wide estimate | 50 to 200 years, most over 100 | Checkatrade, September 2026 |
| Fibre-cement slate | 30 to 50 years | MyBuilder, 21/08/2026 |
The gap between 50 and 200 years in the Checkatrade estimate is the point. The slate itself, the quarry it came from, the fixings and the roof's exposure all change the answer, and no table can tell you where your roof sits in that range without someone looking at it. Fibre-cement slate, a manufactured product, is a different kind of covering with a shorter expected life, as our page on natural and fibre-cement slate sets out.
Why the fixings give out first
A slate is a single piece of stone with two holes in it. It is held to the batten by a nail through each hole, and the weight of the roof, wind lifting from beneath and thermal movement all work on those nails. If the nails are poor quality, such as plain steel or thinly galvanised, they corrode long before the stone shows any age. Slates then creep down the roof as the nail shanks rust through, which is the pattern we describe on our page about nail sickness.
Battens are the other weak link. Softwood battens can rot where damp has been creeping in over many winters, and slate nails lose their grip in soft timber. Lead flashings, valleys and soakers also wear. A roof can have sound slate and still need a major overhaul at 50 or 60 years because everything around the slate has aged. That is not a failure of the slate, and it explains why a roof owner can be told the roof is good for a century and still be quoted for relaying in their lifetime.
What shortens or extends a slate roof's life
Exposure matters. A roof facing the prevailing weather takes more wind and rain than a sheltered one, and the slate maker Cupa puts any site within 30 miles of a coastline that faces west into its severe category. Moss and lichen leave the face of the stone wet for longer, though they do less harm than a heavy-handed pressure wash that strips the surface.
Maintenance counts for more than owners tend to expect, and it is cheap compared with the alternatives. A short inspection after a hard winter, using binoculars from the garden, will show a slipped slate before a stain shows in the bedroom. Gutters that overflow, slipped slates left for a winter, ridge mortar left to crumble and cracked lead all let water in, and the damage spreads along the battens. Walking on a slate roof breaks slates, so foot traffic should be limited and left to people who know where to step. Our page on slipped slates shows what early trouble looks like.
Telling a tired roof from a roof that is nearing its end
Several slipped slates in one area, rust staining under the eaves, rust-coloured dust in the loft and slates that move when pressed by a roofer's hand all point to fixing trouble, not slate trouble. In that case the choice may be to take the slates off, set the sound ones aside, fit fresh battens and underlay, and lay them again on new fixings. In effect that is a reslate which reuses good slate, and it can add several decades to a roof whose stone has plenty of life left.
Flaking, powdery or soft slates are a different matter. If the stone itself is giving up, no re-fixing will help, and new slate is needed. Our survey separates the two by examining the slates, the nails and the battens, and the photographs show you each of them. Tingles, the small strips of lead or copper that hold individual slates, are a stopgap on a sound roof rather than a cure for a tired one, as the page on slate tingles explains.
Cost against the years you get
MyBuilder gives £100 to £180 per m² for a fresh slate roof, split by origin as Welsh slate at £140 to £180, Spanish at £100 to £130 and reclaimed at £110 to £150 per m². Those national figures seem high next to a tile roof until you divide by the years. A covering that lasts nearly a century costs each year less than a covering that has to be replaced twice in the same period.
The comparison only holds if the roof is built to last: good slate, corrosion-resistant fixings, sound battens and well-made leadwork. Our habit is to suggest only the work that clears the fault: a roof with years left is repaired, and one whose fixings have failed is relaid. After a survey you receive pictures of your slopes and a written price, and the work carries a 10-year workmanship guarantee in writing. A roof laid with sound materials, whether new or reclaimed, repays that care for decades. See slate roofing for the whole service.