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650 LAYING UNDERLAY
• Handling: Prevent tears and punctures.
• Laying: Butt jointed onto a dry substrate.
- Fixing edges: With aluminium or galvanized steel staples or 20 x 3 mm extra large
head clout nails.
- Do not lay over eaves and drip/ step aluminium underlaps.
• Ventilation paths: Do not obstruct.
• Protection: Keep dry and cover with aluminium at the earliest opportunity.

FIXING

710 FIXINGS FOR CLIPS
• Nails to timber substrates: Aluminium to BS 1202-3 for aluminium clips. Stainless steel
(austenitic) for stainless steel clips.
- Shank type: Annular ringed or helical threaded.
- Shank diameter: Not less than 2.65 mm.
- Head: Flat.
- Length: Not less than 25 mm or equal to substrate thickness.
• Screws to concrete/ masonry substrates: Sherardized or zinc plated steel to BS 1210,
table 2, or aluminium to BS 1210, table 5 for aluminium clips. Stainless steel
(austenitic) screws to BS 1210, table 4 for stainless steel clips.
- Diameter: Not less than 3.35 mm.
- Length: Not less than 25 mm.
- Washers and plastic plugs: Compatible with screws.
• Screws to composite metal decks: Self tapping, as recommended by the deck and
aluminium manufacturer/ supplier for aluminium or stainless steel clips.

750 CLIPS FOR FLASHINGS/ CROSS JOINTS
• Material: Cut from same alloy and thickness as that being secured.
• Dimensions:
- Width: Not less than 50 mm.
- Length: Sufficient to suit detail.
• Fixing: Secure each clip to substrate with two fixings, not more than 50 mm from
edge of strip/ sheet being fixed.

760 CONTINUOUS CLIPS
• Material: Cut from same alloy and thickness as that being secured.
• Dimensions:
- Width: Sufficient to suit detail.
- Length: Not more than 1.8 m.
• Fixing: To substrate at 150 mm centres. Welt edge of strip/ sheet being fixed to
continuous clip and dress down.

770 WEDGE FIXING INTO JOINTS/ CHASES
• Joint/ chase: Rake out to a depth of not less than 25 mm.
• Aluminium: Fold 25 mm into joint/ chase with a waterstop welted end.
- Fixing: Aluminium wedges at not more than 450 mm centres, at every change of
direction, and with at least two for each piece of aluminium.
• Sealant: Contractor's choice.
- Application: As section Z22.

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