The short answer
Yes, ridge tiles can usually be reused when re-bedding, provided each one is sound. They are lifted, the old mortar is cleaned off, and the good tiles go back on a fresh bed with mechanical fixings. Tiles that are cracked, laminated by frost or chipped across the seat are replaced, ideally with a matching reclaimed or new tile so the ridge still looks like part of the roof.
Why reuse is the first choice
A ridge tile is the curved or angled piece that finishes the roof along its highest line. On most roofs the tiles themselves outlast the mortar under them. The bed fails first: it cracks, shrinks and drops out, the tiles loosen, and rain starts finding its way in. The tiles may be perfectly sound while the thing holding them is not.
That is why we reuse where reuse works. The existing tiles already match the colour and weathering of the roof. A new tile, even from the right manufacturer, can look raw beside the older field tiles for years. Keeping the originals leaves the roof looking like itself, and that counts on a period house, more so where the street sees the ridge.
Reuse is also a matter of repair rather than replacement. A re-bedded ridge of sound tiles is a clear example.
How a tile is checked before it goes back
Each tile is looked at individually as it comes off. A sound tile passes on these points.
- No cracks. A hairline across the tile may open up with the next frost. Tap the tile and a cracked one gives a dull note instead of a clear ring.
- An intact face. Clay tiles can flake on the outside when water freezes in the surface. A tile that has lost its face will keep shedding it and hold water against the bed.
- Level ends and seat. The ends where tiles overlap and the underside where the mortar sits must be unbroken, or the tile will not rest square.
- Clean fixing holes. If the tile is drilled or notched for a mechanical fixing, the hole must not be chipped through.
Concrete ridge tiles are checked the same way. They tend to fade and roughen on the surface with age rather than crack, and a faded but sound concrete tile is still a good tile.
Tiles that fail any one of these points are set aside. What is left is counted, and any shortfall is made up from matching stock before the work starts.
Cleaning off the old mortar
Old mortar has to come off the tile before it goes back. If a tile is laid on top of a layer of hardened mortar, the new bed cannot grip, and the joint fails sooner. The cleaning is done by hand with a bolster or scraper, and takes patience, because hitting a tile too hard can chip it and ruin an otherwise good piece.
On an older house, the old bed may be a lime mortar, which is softer than modern cement and usually comes away more cleanly. Cement mortar is harder and can bond tightly to the tile, so there is more risk of damage when it is removed. The same care applies at the hips, where the roof turns a corner, and our page on hip tile repair covers that.
The roof surface beneath the ridge is also cleaned. Loose debris and crumbled mortar are cleared away so the bedding is laid onto a sound base. Where the top course of tiles is cracked, that is dealt with first, since a new bed on a damaged course would only hide the fault.
When replacement is the better call
Reuse does not suit every ridge. If a large share of the ridge tiles are cracked or flaking, putting them back would mean doing the same job again soon. In that case it is more sensible to renew the ridge in full, using a tile that matches the profile and colour of the roof.
Replacement is also the answer where the ridge has been repaired with the wrong material before. Cement patches over lime, or a mismatched modern ridge on an old clay roof, are common, and they can be corrected while the tiles are off. If you have a tile profile that is no longer made, reclaimed tiles are often the way to keep the match.
A single broken tile does not mean the whole ridge goes. One cracked piece can be swapped for a matching one and the rest reused.
Should the building be listed, or lie within a conservation area, the choice of tile is more than a taste question. Ask B&NES planning before changing the type of ridge, because like-for-like repair and a change of appearance are treated differently.
Fixing them again, and what to ask your roofer
Whether the tiles are new or reused, they should be tied back mechanically. BS 5534:2014 says bedded ridge and hip tiles should include mechanical fixings, because mortar alone cannot be relied upon to hold them. A reused tile with a fresh bed and a proper fixing is as secure as a new one.
Some owners ask whether to move to a dry-fix ridge at the same time. It is a fair question, and the answer turns on the roof itself; our page covering whether a dry verge suits an old house looks at a related choice for the roof edge. On many older houses, tiles bedded in mortar stay the right match.
Two questions are worth putting to any roofer before you agree a price. Ask whether the old tiles will be reused, and ask how many are expected to need replacing. Their answers show whether they have actually looked at your ridge.
The free survey includes pictures of the ridge itself, and the price you are given is fixed and written down. For how long the work takes once it starts, see how long re-bedding takes, and for the full range see the ridge and verge repairs page.
