The short answer
You can, but it is rarely a sensible do-it-yourself job. Lead has to be cut, dressed and fixed to allow for movement, usually from a ladder or scaffold at a chimney or wall, and a poor job leaks. Owners can safely look for signs of failure from below, then call a roofer.
Why leadwork is treated as a trade skill
Lead looks forgiving because it is soft and bends in the hand. That softness is what makes it easy to get wrong. A flashing has to follow the line of a chimney or wall, step up the brickwork or stonework, lap over the roof covering and be held without being nailed through the exposed face. The sheet then has to cope with a summer's expansion and a winter's contraction. Too tight, and it cracks. Too loose, and the wind lifts it.
Each detail has a name and a reason: the soaker that slides under the slates, the step that follows the coursing, the cover flashing that overlaps it. Our guide to lead flashing repairs in Stroud: stepped, cover and apron describes how a roofer builds those parts. The method rests on practice, because lead dressed badly looks fine on the first day and fails at the first hard frost or storm.
The code of the sheet matters too. Leadworx describes 1.80 mm Code 4 as the standard pick for ordinary flashings, with soakers sometimes lighter and valleys heavier. Choosing the right weight for the position is a skilled decision.
The risks that sit around the lead
Much of the danger is not the lead itself. Chimney and wall flashings are at the edge of a roof, often at the highest point on the house. Working from a ladder against guttering, or stepping onto a slope you cannot see the back of, is how falls happen. A lead flashing at a chimney stack in a Stroud terrace may need scaffold access in any case, and MyJobQuote's guide shows that scaffold changes the cost of a flashing job noticeably.
Then there are the materials. Old mortar can be brittle, and cutting into a chimney joint to refix a flashing can loosen bricks. Stone slates and old clay tiles break under a boot. Handling lead dust and offcuts needs sensible hygiene, with hands washed before eating and children kept away from offcuts.
Weather is a third hazard. A flashing that is half finished when rain arrives lets water straight into the wall head, and the lead cannot be dressed properly on a slope that is wet or frosted. Professionals plan the job so that no joint is left open overnight.
A leak that follows a badly done flashing can also run for weeks inside a wall before it shows, and by then the repair is bigger than the original job. A roofer's cost is often smaller than that.
What an owner can safely check
Several checks need only your feet on the ground or the loft floor, and they save whoever repairs the roof time. From outside, using binoculars if need be, look for:
- lead lifted away from the chimney or wall, or curling at the edge
- a visible crack, usually along a fold or across a corner
- pale, dry mortar missing from the joint where the lead is held
- a gap between the flashing and the tiles or slates beside it
- staining on the wall below that suggests water is escaping
From inside, check the ceiling around the chimney breast and the wall plate for damp stains, and look at the timbers around the stack from the loft hatch with a torch. Take photographs with the date. If a stain grows after rain, tell us which room and which side of the house it sits on.
Do not try to seal a failing flashing with a tube of sealant and walk away. Mastic can hide a gap for a season and trap water behind it. See our answer on how lead flashing is held in place for why the fixing, not a bead of sealant, keeps lead in position.
Costs and what a roofer does differently
Cost is usually the reason people consider doing it themselves, so here are the national figures. Published national figures give a sense of scale. MyJobQuote's 2026 guide has a full chimney flashing replacement averaging £570. Checkatrade's repair guide lists lead flashing repairs at £50 to £70 per metre, and stepped flashing at £80 to £120 per metre in Code 5, before VAT. A figure for your house comes only after the survey, in writing.
Against those numbers, the price of lead alone is not the whole bill, and a job done twice costs more than one done properly. A roofer brings the right code of lead, the tools to dress it, the wedges and chasing cutters, and a way to work safely at height. Our workmanship carries a written 10-year guarantee. If you replaced the flashing yourself, no one would stand behind it.
Timing, and when to call
If a flashing has failed and rain is coming through, tell us promptly; the first visit is about stopping the water, and the permanent repair follows. Lead is better fixed in dry, mild spells than in a cold snap, which is why waiting for a calm day beats a rushed repair in bad weather. Our answer on whether leadwork can be done in winter explains what cold and wet do to the work.
Your photographs, sent through the form or WhatsApp, help us judge whether a visit is needed; the number is 01453 933613. The trade as a whole is covered on our lead roofing page.