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H71 Lead sheet coverings/ flashings

TYPES OF LEADWORK

210 GUTTER LINING WITH PROPRIETARY EXPANSION JOINTS
• Substrate: Plywood on rafters at 450 mm centres.
- Preparation: Not required.
• Underlay: Needle punched nonwoven polyester geotextile.
• Type of lead: Rolled to BS EN 12588.
- Thickness: 2.00 or 2.24 mm (Code 5).
• Pretreatment: Apply chalk slurry coat to underside of lead and allow to dry before
laying, followed by chalk paste coat after bossing but before final fixing.
• Proprietary expansion joints: Neoprene (polychloroprene) and lead.
- Manufacturer: Contractor's choice.
Product reference: Contractor's choice.
- Spacing: Within 1 m of each corner and maximum centres of 2000 mm.
- Weld to gutter linings.
• Outlets: site specific.

230 VALLEY GUTTER LINING TO SLATE/ TILE ROOFS
• Underlay: Needle punched nonwoven polyester geotextile.
• Type of lead: Rolled to BS EN 12588.
- Thickness: 2.00 or 2.24 mm (Code 5).
• Pretreatment: Apply chalk slurry coat to underside of lead and allow to dry before
laying, followed by chalk paste coat after bossing but before final fixing.
• Laying: Over and beyond tilting fillets.
• Lengths: Not more than 2000 mm.
- Cross joints: Lapped not less than recomendation to suit roof pitch.
• Fixing: Welt edges. Nail top edge of each sheet. Dress bottom end neatly into
eaves gutter.

322 SOAKERS FOR MITRED HIPS TO SLATE/ PLAIN TILE ROOFS
• Lead:
- Thickness: 1.25 or 1.32 mm (Code 3).
• Dimensions:
- Length: Slate/ tile gauge + lap + 25 mm.
- Underlaps: Not less than 150 mm.

325 SOAKERS FOR MITRED VALLEYS TO SLATE/ PLAIN TILE ROOFS
• Lead:
- Thickness: 1.25 or 1.32 mm (Code 3).
• Dimensions:
- Length: Slate/ tile gauge + lap + 25 mm.
- Underlaps: Not less than 150 mm.

RotF generic (intermediate) NBS 2014 6118-AEW-XX-XX-NBS-A-01