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G30 Metal profiled sheet decking

PERFORMANCE SPECIFIED ROOF/ FLOOR DECKING

150 STRUCTURAL DESIGN OF ROOF DECKING
• Scope of Contractor's design: Profile and thickness of metal decking, types, sizes,
number and spacing of fixings, stiffening around openings and cleader angles to
gables..
• Requirement: Determine structural sizes necessary to support specified loads
without damage or undue deflection.
- Additional requirements: site specific.
- Design standard: In accordance with BS 5950-6.
• Supporting structure: site specific.
• Significant building features: site specific.
• Dead loads: In accordance with BS 6399-1, clause 4.
• Imposed roof loads:
- Standard: In accordance with BS 6399-3.
- Type of activity: access required - site specific uses.
- Other roof loads: site specifics.
• Service loads: site specific.
• Wind loads:
- Standard: In accordance with BS 6399-2, using appropriate location, exposure,
height, building shape, size, and taking account existing and known future
adjacent and attached buildings.
Design method: Contractor's choice.
- Topographic increment: Before applying the same average topographic data in
all directions, check whether actual topographic data gives a worse condition
and use the higher value.
- Shelter from upwind obstructions: Provide justification for assumption.
- Internal pressures (without dominant opening):
Pressure coefficient (Cpi): For each case considered use the more onerous value
of +0.2 or -0.3.
Size effect factor (Ca): Based upon internal volume of storey between party walls.

- Features: site specific.
• Diaphragm loads: site specific.

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