Leadwork Standards – The Complete Guide
Every lead roof should be designed and installed to recognised standards. From material specification through to bay sizing, fixings, and weathering details, compliance is what gives lead its proven 100+ year lifespan. This page is your anchor point for all leadwork standards, with links to detailed child pages on each standard.
Why Standards Matter in Lead Roofing
Lead has one of the longest service lives of any roofing material. But longevity depends entirely on correct design and installation. Bay sizes, joint types, fixings and falls are all governed by formal standards. If these are ignored, cracking, splitting and water ingress will follow.
At The Lead Lads® we work strictly to BS EN 12588, BS 6915, BS 6229 and LSTA Guidelines. This section explains each and why they matter.
BS EN 12588 – Rolled Lead Sheet Specification
This standard defines the manufacture of rolled lead sheet. It guarantees uniform thickness, weight, and mechanical properties so that installers can design with confidence. Sheets are milled to precise tolerances, stamped with identification, and categorised into standard codes (Code 3 to Code 8).
- Code 3 (1.32 mm): soakers and light flashings.
- Code 4 (1.80 mm): step and apron flashings, general use.
- Code 5–6 (2.24–2.65 mm): gutters, dormers, flat roof bays.
- Code 7–8 (3.15–3.50 mm): wide gutters, heritage, domes and spires.
Read BS EN 12588 Guide
Shop Rolled Lead Sheet
BS 6915 – Installation of Lead Sheet, Flashings and Weatherings
BS 6915 is the benchmark installation standard. It sets out how to detail joints, bay sizes, drips, steps and fixings. Following it ensures that lead can expand and contract without fatigue.
- Bay lengths: limited per code and exposure (e.g. 1.5 m for flashings, 2.25 m for Code 6 flat roof bays).
- Joints: correct use of drips, laps and expansion joints.
- Fixings: clips instead of nails through sheet; correct chase depths (~25 mm).
- Underlays: separation layers to prevent abrasion and condensation.
BS 6229 – Flat Roof Construction & Substrates
BS 6229 focuses on the design of flat roofs, including substrate performance. For lead roofing, it means ensuring continuous ventilation, vapour control, and correct deck materials beneath the bays.
- Substrates: stable, ventilated, non-moisture-retentive decks.
- Falls: minimum 1:80 to ensure positive drainage.
- Thermal movement: allowances for expansion/contraction at joints.
LSTA Guidelines – Practical Good Practice
The Lead Sheet Training Academy (LSTA) publishes detailed guidelines for working with lead. These cover bay sizing charts, fixings, bossing, welding, and decorative details. While not statutory, they represent the industry’s most practical handbook and are widely referenced alongside British Standards.
Buying Materials to Standard
When you order from The Lead Shop, you know every roll is BS EN 12588 certified. Accessories including clips, wedges, nails and patination oil are also stocked so you can complete projects to standard. Order by code, width and length with fast delivery.
Leadwork Standards FAQs
What standard covers the manufacture of rolled lead sheet?
BS EN 12588 defines rolled lead sheet specification, thickness and tolerances.
Which standard should I follow for installing lead flashings?
BS 6915 sets out the installation rules for flashings, joints, bay sizes and fixings.
What does BS 6229 cover in relation to lead?
It addresses flat roof design, substrates, ventilation and drainage falls.
Where can I find practical detailing guidance?
The LSTA Guidelines provide detailed diagrams and practical tables for installers.
