The short answer
A Cotswold ridge is built from dressed stone pieces cut to an inverted V, laid along the top of the roof on mortar, with the joints finished flush. The council's 2000 owner guidance says ridges were always formed this way, from plain angled stone. Since BS 5534:2014 a ridge cannot depend on mortar by itself, so we check the fixing on survey.
What a dressed stone ridge looks like
Ridge is the name for the level line at the summit of a pitched roof, where its two slopes join. On stone it is capped by a run of stone pieces, each cut into an inverted V so that it straddles the apex like a saddle. Cotswold District Council's 2000 note for owners states that ridges were always formed from a plain angled section of dressed stone. Dressed means a mason has worked the block to shape, rather than leaving it as it split.
The profile sheds water to either side and covers the top course of slates on each slope. The same note calls a plain straight-pitched roof the simplest type, usually set at 47° to 55°, and the ridge finishes that steep line. Nothing about it is ornament for its own sake. It is the weather-tight cap on the whole roof.
A hip is the sloping corner formed where two roof planes meet on the outside of a building, and on stone roofs hips are often capped the same way. If your roof has hips, the points below apply to them too.
How the ridge stones are bedded
The ridge pieces sit on a bed of mortar spread over the heads of the top slates. The mortar fills the gap between stone and slate, brings the ridge to a true line and seals the joints between neighbouring blocks. Each visible joint is pointed. A band of mortar called flaunching runs along the foot of each side, rising to meet the ridge stone and sealing the junction.
On a traditional roof the mortar is lime, and our guide to lime mortar, torching and pointing on stone roofs covers how it is mixed and used. Lime stays slightly flexible, so a stone roof can move and breathe without the bedding shearing away from the stone.
This is also the part of the roof that takes the weather first. Bedding cracks, shrinks and drops out of ridge joints well before the blocks themselves are tired. On a survey we look at it from the ground, and again from the loft hatch if there is one.
The fixing rule introduced by BS 5534
Marley, in a technical article updated in February 2026, reports that after the 2014 revision of BS 5534 a ridge can no longer rely on its mortar bed to hold ridge and hip tiles down, and that every bedded fitting should have a mechanical fixing too. That is the working position now: a ridge needs a fixing as well as a bed. Mortar bedding is not banned, and the standard does not tell a mason how to dress stone.
For stone, that conversation happens at the survey. A heavy dressed block might be held with a stainless-steel fixing into the timber, or by another method agreed with the owner and, on a protected building, with the conservation officer. We set out the options in your written quote.
Dry-fix ridge systems are tested to BS 8612, and they are made for manufactured tiles. Whether one could work with a hand-cut stone ridge is a design question, and on a listed house consent enters the picture too.
What re-bedding a ridge typically costs
Published guides give prices for common tile roofs, not stone, so treat these as background only. MyBuilder's slate guide, dated August 2026, quotes £300 to £600 to rebed or renew ridge tiles and £200 to £400 for repointing a ridge or hip. MyBuilder's separate dry ridge guide quotes £40 to £60 per metre for a dry-fix system, while Checkatrade gives £50 to £70 per metre for dry ridge and £70 to £100 per metre for dry hip with VAT left off.
A stone ridge is heavier and more individual than a manufactured one, and access on a steep valley lane or terraced hillside changes the scaffold needed. We work out access before quoting, and VAT appears on your quote, as roofing is usually charged at the standard rate.
No figure here predicts your own bill. Once the survey is done, a written quote covers scaffold, labour, stone, mortar and waste.
Where the ridge meets valleys, underlay and other coverings
Where a ridge meets a valley, several lines of water and several joints arrive at one point. Our answer on swept valleys on Cotswold stone roofs covers the valley end of that junction.
What lies under the slates also affects the ridge, because warm moist air rises to the top of the roof and meets the ridge line first. For that, read should a stone roof have underlay.
If you are weighing stone against a different covering, our comparison of Cotswold stone and Welsh slate shows how the two differ at the ridge as well as on the slope.
Whatever the ridge is made of, older roofs get like-for-like materials from us. We clear the site afterwards and take the waste away, and our work carries a 10-year workmanship guarantee in writing. Pictures of the ridge taken from the ground, sent by WhatsApp, the enquiry form or phone on 01453 933613, help us plan the survey. The Cotswold stone roofing hub lists the rest of what we cover.
Signs a ridge needs attention
You can check much of a ridge from the garden. A straight line against the sky is a good sign. Dips, steps or a wavy outline mean blocks have shifted or the timber beneath has moved. Gaps along the joints, mortar crumbs on the slates below, and green growth along the line all point to failing bedding.
After a storm, look for blocks that have turned or slid. A loose ridge stone is heavy, and one that falls can do real harm to whoever is below it. If you can see movement, keep people away from that side and call us. If a ridge has already let water in, the first job is to stop the leak and make the roof safe.