Code 4 to Code 7 lead, dressed and welded to BS 6915 across East London, North London and Essex. The detail that outlasts the roof — when it is done correctly the first time.
WHY SPECIALIST LEAD WORK MATTERS
A properly dressed lead detail installed to current British Standard BS 6915 will routinely outlast the surrounding tiles or slates by decades. Failed or poorly fitted lead, on the other hand, is the single most common cause of internal damp in pitched-roof properties across London.
A significant proportion of the roof repair work we carry out is to correct lead detailing installed by general contractors who have treated it as ordinary roofing. Common faults include oversized bays that crack from thermal movement, missing expansion joints, mortar-only fixing without proper wedging or clipping, and mastic used in place of a properly dressed detail. The cost of doing the job correctly first time is consistently lower than the cost of repeated patch repairs over the following decade.
WHAT WE INSTALL
Every detail addressed using traditional dressing, bossing and welding techniques rather than mastic or sealant shortcuts.
Front aprons, side step flashings and back gutters dressed correctly into the mortar joints rather than relied on at adhesive or mastic. Code 4 and Code 5 lead is used as standard, with Code 7 specified where back gutters carry larger volumes of water.
Open lead valleys collect a disproportionate volume of rainwater on pitched roofs and are typically the first part of a covering to fail. Renewal is carried out with proper upstand detailing, drip discharge over the gutter line and full timber boarding underneath.
Stepped abutments where a roof meets a wall require individual lead soakers slotted between tile or slate courses, weatherproofed with stepped flashing — the detail most often skipped by less specialist contractors.
Where lead is used as flat covering — between two pitched roofs, around dormer cheeks or as a parapet gutter — proper bay sizing, expansion joints and welded detail are essential for long service life.
Complex corners, internal angles and bespoke detailing handled using traditional lead welding and bossing — producing a seamless, monolithic finish reliable for decades.
All new lead is treated with patination oil on completion, preventing the white carbonate staining that otherwise runs down onto adjacent tiles, brickwork or rendered surfaces in the months after installation.
Lead remains a target for opportunistic theft, particularly on single-storey extensions and porch roofs. Replacement is carried out promptly, with anti-theft marking or non-lead substitute specified where a property is repeatedly targeted.
All installations conform to British Standard BS 6915 for lead sheet roofing and cladding — the recognised industry benchmark for service life, bay sizing, fixing methods and expansion allowance.
MATERIAL SPECIFICATION
Lead is supplied by code number — referring to the thickness and weight of the sheet. Using the correct code for the application is the difference between a fifty-year detail and a five-year leak.
A clear four-stage process designed to keep you fully informed from inspection through to sign-off — and to avoid the unexpected issues that often arise during lead detailing work.
01
The lead detail is inspected on site and the underlying cause of any failure identified. The correct lead code, bay sizing and fixing method for the application is then specified.
02
A written quotation is issued setting out materials, lead codes specified, labour and any associated tile, slate or mortar work needed to reinstate the detail.
03
Lead is cut, dressed, welded or bossed on site as required, fixed into chases or mortar joints to current best practice, and finished with patination oil before sign-off.
04
A final inspection confirms satisfaction with the finished detail. Workmanship is guaranteed in writing, with service life on properly executed lead work typically measured in decades rather than years.
Lead work is carried out across East London, North London and Essex — including Waltham Forest, Hackney, Haringey, Redbridge, Newham, Islington and Enfield, alongside postcodes throughout the E, N, IG and RM regions.
Answers to common questions about lead flashing, lead codes, replacement and our specialist process.
Code 4 is used as standard for most domestic chimney flashings, with Code 5 specified for heavier flashings or more exposed positions. Back gutters carrying larger volumes of water typically require Code 6 or Code 7. The correct code depends on the application, exposure and bay size — specifying too thin a code is one of the most common causes of premature lead failure.
Lead is the most durable flashing material available — service life on correctly dressed lead detailing is routinely measured in decades, often outlasting the surrounding tiles or slates. Most premature failures we see are the result of oversized bays cracking from thermal movement, missing expansion joints, or mastic substituted for proper dressing.
Patination oil is applied to new lead on completion to prevent the white carbonate staining that otherwise forms in the months after installation. Without it, run-off can streak onto adjacent tiles, brickwork or render. Application is standard practice on every lead detail we install.
Yes — where a property is repeatedly targeted, lead-substitute materials such as Ubiflex or Code-Lead can be specified instead of traditional rolled lead. We can advise on suitability case by case, as the substitute material is not appropriate for every detail.
Yes — we provide photographic surveys and itemised reports suitable for insurer review, and liaise directly with assessors where this assists in moving the claim forward.
No. Lead work is delivered by our own specialist team rather than subcontracted, which keeps the workmanship standard consistent and removes any dispute over responsibility if a detail needs revisiting.
Yes — site visits and written quotations are free, with no obligation to proceed. Most lead work projects can be priced within a few working days of initial contact.
“Had a leak around the chimney for years — three different roofers patched it with mastic. FNB stripped it back, dressed new Code 5 lead properly into the joints, and it’s been dry through two winters since.”
R Hughes
Leyton, E10
“New valley re-laid in Code 5 lead, properly bossed at the corners and finished with patination oil. Clean job, fair price, came back a week later to check it themselves. Recommended.”
D Karim
Wanstead, E11
Free site visit, free written quotation, no obligation to proceed. Most lead projects can be priced within a few working days of initial contact.
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