Lead is the critical waterproofing material at every junction on your roof — where chimney meets slope, where dormers break the roofline, where valleys channel water. When lead fails, water gets in. We strip and re-dress lead to standards that last 50+ years.
Every roof has vulnerable points where different surfaces meet — chimney stacks, dormer windows, abutment walls, valleys, and soil vent pipe penetrations. At each of these junctions, lead sheet is dressed and fitted to prevent water ingress. When this lead fails — through fatigue, thermal cycling, poor original installation, or sheer age — leaks appear in the most damaging locations: directly into living spaces and structural timbers.
On the 1960s–70s estates, original lead flashings are now 50–60 years old. Code 3 lead was commonly used — thinner than today's standards — and after decades of expansion and contraction it develops fatigue cracks, particularly on south and west-facing elevations where thermal cycling is greatest. Brighton Hill and Kempshott, with their elevated, sun-exposed positions, see accelerated lead fatigue compared to sheltered estates like Black Dam.
On newer 1980s–90s estates like Chineham and Lychpit, some builders used mastic sealant or lead substitute products instead of proper lead. These are now failing at 25–35 years — well ahead of the tiles around them. We strip these out and fit proper code 4 lead.
Period properties around Old Basing and the Top of Town require heritage-standard leadwork. Original 18th and 19th century lead was often thicker gauge, hand-cast, and patinated over decades. We work with code 5 and code 6 lead for heritage applications and apply patination oil to match the appearance of surrounding historic leadwork. Conservation area requirements are fully understood and met.
Valleys channel the highest volume of water on any roof. A failed lead valley causes immediate and often severe water ingress. Across Basingstoke's estates, original valley linings are failing due to both age and debris accumulation from the maturing tree canopy. We strip and reline valleys with new code 4 or code 5 lead, properly dressed with adequate laps and splash guards.
All our leadwork follows the Lead Sheet Association code of practice. We use code 4 lead (1.80mm) minimum for flashings and code 5 (2.24mm) for valleys and heritage applications. Lead is cut, dressed and bossed on site to fit the exact geometry of your roof junction — never pre-formed off site and forced into position. Step flashings are cut individually for each tile course, turned into chased mortar joints, and secured with lead wedges before pointing.
Apron flashings are dressed over the tiles below with adequate lap and dressed tight to the wall above with a minimum 75mm upstand. Every joint accounts for thermal movement — lead expands and contracts significantly, and work that ignores this cracks within a few years regardless of material quality.
Every shortcut in leadwork becomes a future leak. Mastic sealant instead of lead lasts around ten years, not fifty. Self-adhesive lead-effect tape lifts under thermal cycling. Mortar fillets instead of proper flashings crack within five years on exposed positions. Code 3 lead, still used by some contractors to save material cost, fatigues far faster than code 4 and has no place in a permanent repair. over a third of the housing stock dates from the 1960s–70s overspill expansion, so the same failures recur across entire streets.
Period properties require heavier gauge lead and traditional techniques. We use code 5 and code 6 for heritage applications and apply patination oil so new lead weathers to match surrounding original work rather than staining the masonry beneath. Where conservation area or listed building consent applies, we discuss specifications with the conservation officer before starting work.
Chimney flashing replacement: £300–£700. Dormer re-flash: £400–£800. Valley relining: £500–£1,200 per valley. Heritage leadwork quoted individually. Call 0125 624 2410.
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Need a roofer in Basingstoke? Get your free quote today.
Call 0125 624 2410Four steps from first call to completed work. No call-out fee, no obligation, and a written quote before anything starts.
We inspect all lead flashings, valleys, and junctions on your Basingstoke roof from ladder access. We identify fatigue cracks, lifted sections, failed mastic, and mortar fillets that should be lead.
Your quote specifies the lead code, the junctions to be addressed, scaffold requirements, and total cost. We explain why proper lead is worth the investment over sealant or lead substitute.
Old lead or mastic stripped. New lead cut, dressed and bossed on site to fit the exact geometry of each junction. Step flashings chased into mortar joints. Aprons dressed over tiles.
Every junction tested, completed work photographed, site cleaned. You receive a 10-year guarantee on leadwork specified to last 50+ years.
Ready to start? Call 0125 624 2410 for your free survey.
"Chimney flashing on our Brighton Hill semi had split on the south face — 55 years of sun and frost. New code 4 lead properly stepped into the brickwork. Watertight from day one."
"Valley re-lining on our Old Basing cottage. They used code 5 lead with patination oil to match the existing aged lead on the rest of the roof. Conservation officer had no issues. Expert work."
"Dormer flashing on our Lychpit detached was mastic from the original build — no lead at all. Proper step and apron flashing fitted. Should have been done like this in 1986."
Properly installed code 4 lead typically lasts 50–60 years. Heritage-grade code 5 and code 6 can last 80–100+ years. The original code 3 lead on Basingstoke's 1960s estates is now reaching the end of its working life.
The most common cause is failed lead flashing where the chimney meets the roof slope. Lead develops fatigue cracks from decades of thermal expansion and contraction. The tiles can be perfect while the lead between chimney and tiles has failed.
Lead code refers to thickness. Code 3 (1.32mm) was used on 1960s housing — it is thin and fatigues relatively quickly. Code 4 (1.80mm) is current standard for flashings. Code 5 (2.24mm) and code 6 (2.65mm) are used for valleys and heritage work where greater durability is needed.
No — not for long-term waterproofing. Mastic sealants and lead substitute products have a 10–20 year life compared to 50–60+ years for proper lead. They are acceptable as temporary repairs but should be replaced with lead for a permanent solution.
Yes. We carry out heritage leadwork on listed and conservation area properties using appropriate code lead with patination oil finish. We understand the requirements of Basingstoke and Deane's conservation officers.
Standard chimney flashing replacement costs £300–£700 depending on chimney size and access. Scaffold may be required for tall stacks, adding £200–£400. We provide free inspections and written quotes.
Age, debris accumulation, and foot traffic. Leaves and moss block the flow, causing water to pond and find gaps in aged lap joints. Treading on a valley to access other parts of the roof also causes fatigue cracking. We recommend valley inspection as part of annual maintenance.
No call-out fees. No obligation. Just an honest quote from a local Basingstoke roofer who'll turn up when they say they will.
0125 624 2410