The short answer
A lead saddle is a shaped piece of lead that covers the junction where a roof ridge meets a wall, or the high side of a chimney stack. It sheds water round the obstruction and over the side flashings. Cracking at the folds from repeated movement is the commonest fault, and a repair or a new saddle follows what the survey finds.
Where a saddle sits, and what it does
Water running down a roof slope meets a chimney stack or a rising wall head on. The face of the stack on the uphill side would collect that water, so a saddle is built there: a small ridge of lead, shaped like a tent roof, that parts the flow and steers it down either flank of the chimney. At the foot of the stack the apron does the same job in the other direction.
The same piece is used where the ridge of a roof runs into a gable wall or a tall chimney, and the junction has no easy way to shed water. The saddle covers the ridge end, turns up the wall and ties into the flashings on each side. It is a small piece but a complex one, because several lead surfaces have to meet at angles. Our page on the lead apron covers the matching piece at the foot.
Saddles on ridges that meet a wall
Not every saddle sits on a chimney. Where the ridge of a lower roof runs up to a taller wall, such as a side extension meeting the main house, the end of the ridge butts against the brickwork and a gap opens between the ridge tiles and the wall. A lead saddle closes that gap. It lies over the ridge end, turns up the wall behind it and laps over the flashings on both slopes.
These junctions are easy to get wrong because three planes meet in a small space. Ridge tiles, bedding and a stepped flashing all have to be tidied up before the lead goes on. On older houses the saddle may be the only thing keeping rain out of the roof void at that corner. The rest of our lead roofing pages cover the pieces that meet it.
Why saddles crack and split
A saddle is folded from a flat sheet, and each fold is a place where the metal is bent and stressed. Lead expands in the sun and shrinks in the cold, and the folds take the strain in the same spots, day after day. Over years the metal at the creases work-hardens and cracks. A saddle made too tightly, or one with the sheet nailed where it should be free to slide, will crack sooner.
Poor dressing is another cause. If the lead was not pressed neatly into the angles, water sits in the folds and attacks the surface. Stack movement, repointing in hard cement and loose wedges all add to it. Our why lead cracks page goes through the reasons in detail. You may notice it as a wet patch on the loft timbers beside the chimney, or a tide mark on the chimney breast upstairs.
Repair or replace a lead saddle
A single crack at a fold can be burned shut, which means melting a thin strip of lead into it, or covered with a patch. That is sensible when the rest of the saddle is in good shape. A saddle with cracks at several folds, one that has thinned with age, or one that has slumped away from the stack is better replaced, because a repair on tired lead fails beside the mend.
A new saddle is made to fit the actual stack. The roofer cuts the lead, folds it, dresses it into the angles and ties it into the side flashings and the apron, so the whole set sheds water together. Wedges and pointing hold the upper edges. We inspect the side flashings on the same visit, since the saddle depends on them. Lead has a long working life when it is laid well, which our page on how long a lead roof lasts looks at.
Which code, and which metal
Royston's table lists Code 4, 5 and 6 for flashings, and Leadworx calls Code 4 the usual general choice. A saddle with several sharp folds is more at risk than a plain flashing, so Code 5 is often a sensible pick for an exposed stack. A thicker sheet is stiffer and harder to fold neatly, so the maker has to balance the two.
Some owners ask about another metal in place of lead. Copper and zinc are both used on roofs, and each behaves differently when it moves and weathers. Our page on lead alternatives compares them. On a traditional building lead is usually still the better match for the look and for how it dresses into awkward shapes.
Cost drivers and the survey
MyJobQuote's September 2026 guide gives national typical figures for chimney leadwork: a patch at £150 to £250, and full replacement at £350 to £460 without scaffold or £700 to £920 with it. A saddle is part of that wider chimney leadwork. What changes the cost on a real roof is the height of the stack, the access needed, how many pieces must be renewed and whether the brickwork needs repointing.
The survey photographs show the saddle from close range, including the folds, the joins and the state of the pointing. A written quote follows. If a burnt seam or a patch will cure the leak, we will tell you that and not push for a new saddle. Ten years' guarantee on the workmanship is given in writing. When you compare quotes, see that VAT and scaffolding are included. Call 01793 626096 or use WhatsApp.