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leadwork

15 articles

BS EN 12588 Lead Sheet Standard: Code Numbers 3–8, Thicknesses and Which Code to Use Where

BS EN 12588 Code 3–8: thicknesses (1.32mm to 3.55mm), weights (14.97 to 40.26 kg/m²), colour coding system (green=3 to orange=8), application guide by element, thermal expansion calculations
LCA and LEADSKILLS Qualification: Levels 1–3, Training Centres and Why LCA Certification Matters to Clients

LEADSKILLS Levels 1–3 (introductory to heritage), approved training centres, NVQ equivalencies, CSCS card routes, LCA membership vs individual certification, why heritage clients specify LCA certified leadworkers
Lead and Other Metals Compatibility: Avoiding Contact with Zinc, Aluminium and Copper — Separation Details

Lead vs zinc (severe corrosion), lead vs aluminium (severe), lead vs copper (mild), lead vs stainless (negligible), separation methods (bituminous felt, EPDM, neoprene), run-off separation requirements
Lead Bossing Techniques: Tools, Wood-Cored Roll Method, Internal and External Angles

Internal and external angle bossing step-by-step, wood-cored roll with copper rivets (max 150mm spacing), annealing at 150–200°C, tool list (bossing mallet 450g, bossing stick, chase wedge), Code 4 minimum for bossing
Lead Chimney Flashings: Back Gutter, Side Step-and-Covers, Front Apron and Soakers — Step-by-Step Details

Four-element chimney set (back gutter, step-and-cover sides, front apron), Code 4 throughout, back gutter 75mm wide minimum, step soakers at each tile course, front apron 150mm up chimney and 150mm onto tiles
Lead Dormer Flashings: Cheek Flashings, Back Gutters, Step-and-Cover Details and Thermal Movement Provision

Cheek flashings, back gutter (75mm depth, 150mm width minimum, Code 4), back gutter outlets, step-and-cover at cheek/roof junction, thermal movement provision per element, common failure modes
Lead Fixings and Tacks: Copper Clout Nails, Stainless Clips, Spacing and Avoiding Electrolytic Corrosion

Copper clout nails (40mm × 3.35mm) or stainless clips, 500mm maximum centres (450mm exposed), lead tack minimum 50mm × 50mm Code 3, why zinc/galvanised fixings cause electrolytic failure, substrate pull-out values
Lead Flat Roof Coverings: Maximum Bay Sizes for Each Code, Drips, Hollow Roll and Dog-Ear Details

Code 5 minimum, bay maximums (Code 5: 2,250mm × 675mm; Code 6: 3,000mm × 850mm), hollow roll 50mm × 50mm minimum, drip 50mm minimum, dog-ear corners, fall 1:80 recommended
Lead Hip and Ridge Rolls: Bossing vs Machine-Forming, Tack Fixing and Code Selection

Code 4 minimum, 1,500mm maximum bay, tack fixing at 500mm centres, bossing vs machine-forming, saddle and gusset pieces at valley/hip junctions, common split and lifting failure modes
Lead Parapet Gutters: Minimum Width, Falls, Drips and Outlet Positions to Avoid Ponding

Minimum 150mm width (225mm for catchments over 50m²), Code 5 standard, falls 1:80 minimum, drips at 1,500mm maximum, outlet sizing by BS EN 12056-3 catchment calculation, mandatory overflow sump
Lead Recycling and Waste: Lead Sheet as Hazardous Waste, Dust Control Under COSHH and EWC Codes

EWC code 17 04 03 (hazardous), consignment notes and registered carrier, scrap value £1–£1.80/kg, CLAW Regulations 2002 OEL 0.15 mg/m³, no dry cutting/grinding, blood lead monitoring thresholds
Lead Soakers and Cover Flashings: Code 3 Soakers With Code 4 Covers, Lap Lengths and Fixing Details

Code 3 soakers with Code 4 cover flashings, soaker sizing formula (gauge + lap + 25mm), cover flashing 65mm minimum into joint, 75mm lap, maximum 1,500mm bay length, pointing materials (lead wool preferred)
Lead Thermal Expansion Provision: Maximum Bay Lengths, Drip Heights, Roll Dimensions and Why It Matters

Lead expansion coefficient 29.3×10⁻⁶/°C, UK roof temperature range −10°C to +80°C, bay limits by code (Code 3/4: 1,500mm; Code 5: 2,250mm; Code 6: 3,000mm), failure diagnosis from undersized bays
Lead Valley Gutters: Open vs Closed Valleys, Minimum Width, Code Selection and Drip Details

Open vs closed vs swept vs woven valley types, minimum 150mm clearance width, Code 4 standard (Code 5 for large catchments), maximum 1,500mm bays, 50mm drip height, catchment area calculation method
Leadwork on Listed Buildings: Historic England Guidance, Matching Original Profiles and LCA Recommendations

Listed Building Consent for material substitution, like-for-like code weight matching (Code 6–8 on pre-1900 buildings), LCA Heritage certification, conservation officer pre-application advice, natural vs artificial patination