In short
MyJobQuote's 2026 guide gives Welsh natural slate at £100 to £130 a square metre installed, rising to £120 to £150 on complex roofs, and Spanish slate at £70 to £93. BestBuilders puts a whole three-bed semi in natural slate at £11,000 to £18,500. On an older house in Powys or Ceredigion the biggest variables are how much of the existing Welsh slate can be re-laid, the amount of timber repair, the scaffold, and whether the conservation area or national park requires Welsh slate on the visible slopes.
This is a job for our Slate re-roofing service.
Per square metre
| Slate | Installed cost per m² (MyJobQuote, 2026) |
|---|---|
| Welsh natural slate, straightforward roof | £100 to £130 |
| Welsh natural slate, complex roof | £120 to £150 |
| Spanish natural slate | £70 to £93 |
Those are supply-and-fit figures for the slating itself. Scaffolding, stripping and disposal, membrane and battens, timber repair and leadwork sit on top.
The whole roof
BestBuilders' 2026 guide gives a three-bed semi-detached house at £11,000 to £18,500 in natural slate, against £9,500 to £15,500 in clay tile and £6,500 to £11,500 in concrete. FixMyRoof gives £13,000 to £22,000 for a three-bed semi in Welsh or reclaimed slate. A detached farmhouse with a big roof and awkward access is beyond those ranges.
What moves the price on a Mid Wales house
How much slate comes back
Sound Welsh slate is graded and re-laid, usually on the front. On a Victorian roof a third to a half often comes back, and every slate that does is one you do not buy.
Timber
Rafter ends and wall plates that have been wet for decades. A quote should carry a stated allowance and a rate for anything beyond it.
Scaffold and access
A terrace on a steep street in New Quay or Knighton costs more to scaffold than a bungalow with a drive.
The planning position
In a conservation area or inside Bannau Brycheiniog or Eryri, Welsh slate is expected on visible slopes. That sets the material and the price.
Getting a real number
An average is not a quote. Tell us about the roof and we pass it to one local roofer, who looks at it and prices it in writing.