The short answer
Repair old leadwork when the metal is sound and the fault is in the fixing, the pointing or one small split. Replace it when the lead has thinned, cracked in many places or been patched past the point of sense. Age alone is not the test, because MyJobQuote puts lead flashing at over 80 years. Condition is the test, and photographs of it settle the question.
Age is not the test
Many people assume lead has to be replaced once it is old. The published figures do not support that. MyJobQuote (Sept 2026) puts lead flashing at "over 80 years", and HomeBuilding (Sep 2025) gives lead on a flat roof "60-100 years". Both are lifespans for fitted lead, neither is a promise and each is only a typical range.
A flashing that is forty years old and sound is a better buy than a new one fitted badly. What matters is what condition the metal is in, and what the fault is.
A fixing fault is different from a metal fault. If the pointing has crumbled or a wedge has dropped out, the lead is intact and the repair is to re-wedge and re-point. If the lead itself is thin, pitted or split across many sheets, the metal has done its job and is spent.
That separation is why a quote that says the leadwork is old and must be replaced deserves a question. Ask what the lead looks like, where it has failed and what the cause is. Our page on how long lead flashing lasts goes through the published figures.
Signs that a repair will do
A repair is the right call when the following are true:
- the leak traces to a single point, such as one split, one open joint or one lifted edge;
- the lead around the fault is flat, supple and of a decent thickness, with no pitting;
- the pointing has failed but the chase behind it is sound;
- the fixings, wedges and clips need replacing but the sheet itself is fine;
- earlier repairs, if any, are few and have held.
In these cases, the job is a re-fix of the lead, a patch to a split or re-pointing of the chase. It costs far less than new lead and leaves sound material in place.
A repair is what we recommend before a larger job, and the photographs behind that advice are yours to see. Our lead flashing repair page describes what a repair involves.
A repair is also the sensible answer when the leak is recent. Catching a lifted edge or an open chase early, before water has damaged the timber behind, keeps the job small. A leak that has run for months may have changed the answer, and that is why a prompt look matters.
Where patching stops
A patch is a piece of new lead dressed over a split or a hole and fixed into place. It can be a sound, lasting repair on a single fault. It stops being sensible when there are too many of them.
Warning signs that a patch is no longer enough:
- several splits on the same sheet, which tells you the whole sheet is stressed;
- earlier patches that are themselves cracking or lifting;
- lead that has thinned to the point where it tears when moved;
- a joint buried under layers of sealant from old attempts, hiding what is beneath;
- repeated leaks in the same place after repairs.
Each patch adds joins and a little stiffness, and a roof covered in patches is harder to keep watertight than a single clean sheet. At some point replacement costs less than another round of repairs, and it ends the cycle.
Replacement is also the answer where the fall of a lead roof is wrong, since a repair to the lead does not correct the deck beneath it. Our page on why a lead roof leaks explains how falls come into it.
How we advise you
The survey records the lead, close up. We note its thickness at an exposed edge, the number and age of any patches, the pointing, the fixings and what the boards or brickwork behind look like. You get photographs of each, and plain words about what they mean.
Then we give you a view. Where a repair will do, the quote is for the repair. Where the lead is past it, you are told that and given the code and extent of the replacement, referring to Royston's code table, which runs from 1.32 mm for Code 3 to 3.55 mm for Code 8.
The biggest job is not always the right one. Sometimes the answer is to repair now and plan replacement for a convenient time, for example when a scaffold is already up for other work.
Our quote is one total for what we recommend. With a second quote in hand, ask both firms whether the lead is being repaired or renewed, and which code is meant.
The lead roofing hub explains how the leadwork on a roof fits together, from Farnborough out to the villages.
