Sorting the sound from the failed
When a slope is stripped, every tile comes off by hand and goes into one of three piles: good enough to relay, kept for cutting or the awkward corners, and scrap. The sorting is done tile by tile, because two tiles that look identical from the garden can be very different in the hand, and a tile that fails after relaying means opening the slope again.
The checks are practical ones:
- Cracks, including hairline ones that run out from the nail hole.
- Flaking or layers peeling from the face, which means frost has got into the clay.
- A corner or edge broken away, so the tile no longer covers the joint below it.
- A hole that has enlarged, so the peg or nail no longer holds.
- A dull thud when the tile is tapped, rather than a clear ring.
A re-roof that reuses the tiles still replaces what lies beneath them. Old battens, which may have gone soft, and old underlay come off, and new ones go on before the sound tiles return to the slope. Only the covering is recycled; the layers that keep water out are renewed.
Reclaimed tiles to make up numbers
Reuse may not cover a whole roof. Cracked tiles, tiles lost to earlier repairs and tiles broken during stripping leave a shortfall, and that shortfall has to come from somewhere. Reclaimed tiles taken from other roofs are the usual source, because a new tile of a different make rarely matches the weathered colour and texture of the old ones.
Roofers often spread reclaimed tiles through the slope rather than laying them as a block. A patch of new-looking tiles on a front slope stands out, so the mix is worked across the roof, or the better-weathered tiles are kept for the side the street can see. Where a slope faces a road, that choice matters more.
The page on matching old roof tiles explains the sourcing in more detail, and peg tiles against plain tiles compares the two kinds.
Ask the roofer how many tiles the sorting is expected to pass, and what the plan is if the sorted pile turns out smaller than hoped. A good plan names where any extra tiles will come from before the roof is opened up.
Fixing reused tiles to current practice
Reusing a tile does not mean reusing an old way of fixing it. BS 5534:2014+A2:2018, the code for slating and tiling, reaches normal re-roofing work and repairs, according to Marley. It is not itself the law, but it is the standard that careful work follows.
In practice the roof is fixed to a specification calculated for the site's exposure, with nails or clips as that specification requires. Marley reads the 2015 amendments to BS 5534 as meaning mortar by itself can no longer be trusted to hold a covering on, so ridge and hip tiles are fixed mechanically. BS 8612:2018 is the specification for fixing ridge, hip and verge tiles dry.
Approved Document C expects every tile to be fixed appropriately. A sound old tile on a new batten with a new fixing meets that, and a sound old tile held by a decayed nail does not.
A re-roof may also need a Building Regulations route. The Planning Portal's test is less than 25 per cent of the building envelope and less than 50 per cent of the roof affected. At Dover addresses, Dover District Council's building control page puts replacing roof coverings, like for like included, among the jobs that need approval, so the route is confirmed first.
Consent where the roof's character is at stake
On an ordinary house a re-roof is normally permitted development under Class C of the General Permitted Development Order. A listed house keeps that right but also needs listed building consent before anything is changed that bears on its character, under section 7 of the Planning (Listed Buildings and Conservation Areas) Act 1990. Where original peg tiles are going back, the application can say how many.
Conservation areas carry rules of their own. On Thanet's conservation area page, work that matches what is there already is described as less likely to call for planning permission. Article 4 directions can withdraw rights in particular places, so ask your council early whether one covers the street.
The page on listed house tile repairs covers the consent route in more depth. For the whole service, see pitched roofing.
Once the sorting plan is agreed, the reuse plan comes with the written total, showing what goes back on the roof, slope by slope, and which reclaimed or new tiles are bought in to make up the shortfall.
