What Is a Lead Saddle?

Where a saddle sits and why it is needed

A ridge is the line where two roof slopes meet at the top. When that line runs into a chimney or a taller wall, the two slopes, the ridge and the vertical face all arrive at the same point. Flat flashings cannot cover that junction on their own, because lead dressed in a straight line leaves a gap at the corner where the planes change direction.

The saddle fills that gap. It is cut from a single sheet, folded over the ridge like a hood, and its upper edge is turned into a groove in the brickwork so rain running down the face of the stack cannot slip behind it. Its lower edges lap over the lead flashings and the ridge tiles beside it. On a chimney that sits on the ridge line, you will usually find one saddle at the back and a different arrangement at the front.

How a lead saddle is made

No two junctions are quite the same, so a leadworker forms each saddle by hand. The sheet is cut with generous margins, then folded and tapped into shape with a dresser (a smooth wooden or plastic tool) and a bossing mallet until it follows the angles of the roof. Lead is soft enough to be worked cold into tight corners, which is the main reason it is used for this job and not a stiff metal.

The saddle is not stuck down with sealant. It is held by its own shape, by the groove in the wall and by lead clips at the edges, which keep it from lifting in wind but allow it to move as the sheet warms and cools. A saddle that is fixed rigidly at every edge will split within a few seasons, because lead expands and contracts with temperature. Our page on why lead cracks covers that movement in more detail.

How a saddle fails

The usual failure is not the lead itself. The mortar that locks the top edge into the wall perishes, the lead drops out of its groove, and wind starts lifting the corner. Once the corner is open, water runs straight into the junction and can track down the inside of the chimney breast or along the ridge timber.

The second cause is a crack at the fold where the saddle bends over the ridge. A fold that was worked too hard, or a saddle cut from a sheet that was too thin for the span, will tear along the crease. The third is a patch of sealant or bitumen tape put on by someone else. It hides the problem for a winter and then peels, and a repair that has to cut through it takes longer. We would rather see the original lead and judge it fairly.

Choosing the lead for a saddle

Saddles are cut from lead that is thick enough to hold a crease without tearing, and the thickness is given as a code number. A heavier code costs more per sheet but resists the folding stress better, so the choice is a matter of the span and the exposure, not just price. On the exposed ridge of a Hampshire or Berkshire house the wind lifts at the corner first, which is another reason to fit proper clips and a deep groove.

Patination oil is brushed on after fitting to stop the surface weathering unevenly, which also keeps the new grey lead from streaking the brick below it.

Repair or replace

A loose saddle with sound lead can often be re-fixed: the groove is raked out, the lead is re-wedged and the joint repointed. A cracked saddle is usually better replaced, because lead that has split at the fold will split again beside any patch. A new one is cut to the old template, which keeps the job to a few hours when the surrounding flashings are sound.

If the flashings either side are also failing, we say so, and you can see it in the survey photos before you decide. Our guide to soakers and step flashing shows how the pieces beside a saddle fit together. The wider picture of our lead work is on the lead roofing and leadwork page.