When a repair is the fair answer
Lead is soft and heavy, and it can be worked again on site, which is why a repair is a real option and not a polite word for a stopgap. The cases where it suits are the ones with a clear, single cause and sound metal around the damage.
A slate or a ladder may have struck the sheet and split it in one spot. A clip may have worked loose, so one edge has lifted in the wind. A fixing may have corroded away, leaving a short length free to flap. In each case the lead either side is flat, supple and unmarked, and the job is to put right the one fault.
Before agreeing to a repair we walk the whole run. A flashing is the metal strip that seals at the line where a slope runs into masonry or glazing, and it fails at its weakest point. If that point is the only point, repair it. If you can see the same fault three times along the same flashing, the weakest point is not the real story.
Why patches on tired lead rarely last
Lead expands and contracts with every change in temperature, and over years that movement can leave fine cracks, often along bends and folds where the metal works hardest. Think of bending a paperclip: the metal does not fail on the first bend but on the hundredth. This is fatigue.
A patch on fatigued lead does not undo that history. It adds a stiff edge in a place that wants to flex, and the next crack tends to start beside it. Sealant smeared over a crack looks neat for one winter, then lifts, because the lead underneath keeps moving.
These findings argue for new lead:
- several hairline cracks along one run, not a single split
- thin or torn lead, or lead pulled out of its chase, the groove cut into the brickwork to hold the top edge
- earlier patches that have themselves failed
- sheets so long that they have buckled
A single one of them may still be mendable. Two or three together rarely are. Age alone settles nothing: a sound old sheet beats a badly fixed new one.
What replacement to the specification involves
New lead is not just a fresh sheet laid over the old line. The specification is the written list of what goes where: the lead code (the thickness grade), the length of each piece, the laps where pieces overlap, the fixings and how each edge is held. Lead roofing follows BS 6915, which Approved Document C points to.
The Royston Lead brochure says Code 3 is "Recommended for lead soakers only", and a soaker is the small folded piece of lead that sits working with each course of tiles or slates against a wall. For every other detail the code is set in the specification, and your roofer should tell you which one is going on your roof.
Replacement means the old lead comes off, the substrate beneath is checked for damp or rot, and new pieces are cut and dressed to the shape of the roof. The top edge is held in the chase with wedges and pointed over. Pieces are kept short enough to move without tearing.
The old lead leaves site with the other rubble and offcuts, and the roof is left swept.
What it costs and how to compare
MyJobQuote, in September 2026, priced chimney leadwork replacement at "between £350 and £920", as a typical UK range. The range is national, so treat it as a starting point for a Thanet job and not as a quote.
What moves the price on a particular roof is the length of lead involved, how many pieces meet at awkward corners, how high the work is and whether the substrate needs attention. A single split fixed in place and a whole stack re-dressed are very different jobs, which is why nobody can price lead from a photograph of one crack.
When you ask for quotes, ask each roofer to say in plain words whether the work is a repair or a replacement, and what lead code it uses. A quote that cannot say is guessing.
For the repair end of the spectrum, see lead flashing repairs; everything else we do in this metal is gathered under lead roofing. If cracking is your main worry, why lead flashing cracks goes through the causes.
