Flashing is the strip of metal that bridges the joint between a roof and something that rises through it or stands against it: a chimney, a party wall, a dormer cheek, a porch. Rain runs down the roof, meets that joint and has to be turned away from the gap, whether the wall beside it is brick, render or stone. Lead is the traditional metal for the job because it can be bent into the shape of the joint and stays put.
When a flashing lifts, cracks or comes away from the mortar, water gets behind it and the symptom is a stain on a chimney breast or a damp patch beside a party wall. The next question is cost, and national figures vary a lot because a "flashing" can be a short length at the back of a porch or a full set round a tall chimney.
We set out below what the cost guides publish for chimney leadwork, what moves a flashing price up or down, and the checks that make two quotes comparable. The figures below come from named national guides, so read them as a yardstick only. Your own price comes from the survey.
The range published for chimney leadwork
MyJobQuote, in a guide dated September 2026, puts full leadwork on a chimney between £350 and £920, and says the figure depends on scaffold. It is a typical UK range, and the only published one we hold that deals specifically with lead flashing.
Why the range is so wide
A chimney can be a small single stack on a bungalow reached from a roof ladder, or a tall double stack on a three-storey house that needs a full scaffold. The leadwork itself can be about the same weight in both cases, yet the second job costs a good deal more because of the access. The guide's own wording points at this: the range moves with the scaffold, not with the lead alone.
What "full leadwork" means
A chimney is normally flashed with several pieces: an apron at the front where the stack meets the slope, stepped flashings climbing both sides, and, behind the stack, a back gutter that carries away water which would otherwise collect. "Full" means all of those are renewed, not one patched. If only one side has failed, the job and its price are smaller.
What the range does not cover
The range is for the leadwork. It does not tell you about the state of the chimney itself, and a stack that needs repointing or a new flaunching, the mortar cap on top, is a separate piece of work. Repointing is priced once the stack has been looked at, since the amount of weathered mortar varies.
What pushes a flashing price up or down
Four site facts account for most of the difference between a small flashing quote and a large one. All four can be seen from the ground, from the roof or from the loft before a price is written, which is why we do not set one on a phone call.
Where the flashing is
A chimney needs more pieces than a straight wall abutment, and a dormer needs more again, because its cheeks, front and roof edge all meet the main roof. A bay window roof or a porch has its own run of lead. Our guide to lead flashing repair shows how the common forms are built and mended.
Length and number of pieces
Lead is sold by weight, and every extra metre of flashing is extra metal and extra dressing time. A long party wall abutment on a terrace costs more than a short return at the back of a lean-to.
Height and access
A chimney on a ridge two storeys up is worked from scaffold. The scaffold sits on the job for days, and that time is a real share of the price. Scaffold that would block a public pavement or road falls under section 169 of the Highways Act 1980, with a licence from the highway authority that takes time to arrange, so ask who is applying for it.
The lead code
Royston Lead's brochure lists Code 4 and Code 5 for flashings, and Code 3 for soakers only. Code 5 is thicker and heavier than Code 4, so it costs more to buy. Our answer on Code 4 against Code 5 explains which suits which flashing.
Repair, re-dress or replace
Not every failed flashing needs replacing. Because the quote follows what the survey finds, the same stain on a ceiling can lead to three different jobs and three different prices.
A repair
Where the lead is in good order and just a short length has lifted or pulled free of the wall, it can be re-fixed or a section let in. That is the smaller job, and it is the right answer when the metal is in good order.
A re-dress
Sometimes the lead is sound but the mortar it was fixed into has crumbled, so it hangs loose. The mortar joint is raked out, the lead is re-fixed in a lead wedge or a proper chase and the joint is repointed. The metal is reused and the saving shows in the price.
A replacement
If the lead has cracked in several places, has been patched more than once or has thinned with age, new lead is the sensible fix. Sealant is not a repair here. Smearing it over a split closes the gap for a short while and hides the problem, and the next frost opens it again.
The sound-lead case
Lead flashing is long-lived. MyJobQuote gives it a life of over 80 years at the low end, which is no promise, but it does mean an old yet sound flashing is not a case for replacement. The photos from the survey show which case you have.
Why the order of the questions matters
It is tempting to ask for a price before anyone has looked at the roof. A figure given down the phone has to assume the worst or the best, and either way it is a guess. Looking first means the price describes your flashing and not an average one, and it lets you choose between the repair, the re-dress and the replacement with the photographs in your hand.
Chimneys, party walls and the work around the lead
Flashings rarely fail in isolation. The surrounding masonry decides how long a new flashing will hold, and that affects what you pay and what you are told.
The stack
A chimney stack takes the weather on all four faces. Crumbling mortar lets water into the brickwork, and water behind lead works its way out as a stain inside the house. If the survey shows the stack needs repointing or its flaunching renewed, the sensible order is to do that work with the leadwork, because the scaffold is already up.
A party wall
Where the roof abuts a neighbour's party wall, the flashing runs along the join and is fixed into the masonry. If the work involves cutting into the shared wall, a party wall notice may be needed, and the Party Wall etc. Act sets a notice period; a party wall surveyor is the person to ask, not building control.
Removing a chimney
If you are thinking of taking a chimney down instead of repairing it, that is a larger job. MyJobQuote gives £1,200 to £3,500 to remove a chimney breast (August 2026), and Building Regulations approval always applies, as the breast forms part of the building's structure. The flashing then disappears along with the stack, and the roof is made good. Whether that is worth doing depends on whether the chimney is still used, what it supports inside the house and what the loft and bedrooms below would need afterwards, so it is a decision to take with the survey in hand.
Reading two flashing quotes side by side
Quotes for lead work differ in wording more than in price, so it pays to read what each one actually promises. Ask for these points to be written down, because a quote that is vague about them is the one most likely to grow once the work starts.
Which pieces are being renewed
A quote that says "lead flashings to chimney" may mean the whole set or the front apron only. Ask which pieces, which sides and how the lead is fixed to the masonry. A good quote names the code of lead as well.
Whether scaffold is included
The MyJobQuote range is explicitly scaffold dependent, so a figure that leaves scaffold out and one that includes it are not the same price. Ask each roofer to say what access they will use and whether it is in the total.
Whether VAT is included
The standard VAT rate is 20%. A figure without VAT will look lower than one with it, and the gap is real money. Ask for the VAT position to be stated on the page.
The price we give
Once we have surveyed, a single written total reaches you with the photographs of the flashing and chimney that explain it. Citizens Advice recommends at least 3 written quotes before you decide, and the comparison is fair only if every roofer has looked at the same chimney. For the wider picture, the lead roofing and leadwork page sets out the lead jobs we carry out.
Lead against other flashing materials
Lead is not the only way to flash a joint, and a roofer who insists it is the only way is not giving you the whole picture. Each option has a place, and the price depends on which you choose.
Lead
It is soft, easily dressed to awkward shapes and weathers to a stable grey patina. It is the usual choice on older houses, on slate roofs and on listed or conservation homes, where the traditional detail matters.
Lead-free and bitumen-based strips
Self-adhesive and flexible strip products are used on some modern roofs and for quick repairs. They are lighter and quicker to fit. They are less suited to period detail, and the lead on an older house is usually the better match. Our guide on lead flashing alternatives compares them in more detail.
Zinc and other metals
Zinc is used on some roofs. VMZinc cites a BRE Environmental Product Declaration that "states 100 years" for zinc. That is a manufacturer's citation for the material, so read it as such.
Choosing on your roof
The right material depends on the age and style of the house, the roof covering and whether the building is in a conservation area. On a Victorian terrace around North Camp or South Farnborough, where the housing was laid out from the 1860s, lead is the likelier match for the original work. The survey says what is there now and what we would put back. On a conservation or listed home the choice may also be a consent matter, and we raise that early rather than after the lead is ordered.
