Design Loadings

Typical design loads for roof cladding are:

Dead = 0.1 kN/m²
Imposed = 0.6 kN/m²
Wind (general) = 1.0 kN/m² uplift
Wind (eaves/gable) = 1.2 kN/m² uplift

Roof Panel Strength

Based on KS1000 RW load span tables for a 80mm thick, double spanning panel with purlins at 2000mm centres;

Allowable downward load = 4.19kN/m²
Allowable suction load = 2.58 kN/m²
The panels will therefore support the loads.

Note: The increased insulation thickness required to meet Part L2: 2002 U-values for cladding panels has resulted in large increases in panel beam strength. The limiting factor for span on most applications will be fastener strength.

Roof Fasteners

The fastener arrangements indicated in the roof sections should be checked for adequate wind suction capacity.

If the panels have 0.5mm thick facings and are valley fixed to 1.6mm thick steel purlins at 2000mm centres, then the maximum design suction load on each fastener is:

Refer to Fastener Specification within the relevant roof section

Permissible load (Pull over) is 1.8 kN
Permissible load (Pull out) is 1.8 kN
These loadings both exceed the fastener design load allowing standard fastener arrangements to be used.

Wall Panel Strength

Based on KS1000 MR load span tables for 70mm thick, double spanning panels with cladding rails at 3000mm centres.

Allowable pressure load = 1.98 kN/m²
Allowable suction load = 1.49 kN/m²
These both exceed the example design loads.

Wall Fasteners

The fastener arrangements indicated in the wall sections should be checked for adequate wind suction capacity.

If the panels have 0.63mm thick outer faces and are fixed to 6mm thick steel rails at 3000mm centres, then the maximum design suction load on each fastener is calculated as follows:

Refer to Fastener Specification within the relevant wall section

Permissible load (Pull over single fastener) = 2.6 kN
Permissible load (Pull over double fastener) = 5.2 kN
Permissible load (Pull out) = 6.0 kN

These loadings both exceed the fastener design load allowing standard fastener arrangements to be used.

Chill Store Buildings

When utilising external roof and wall cladding systems as a chill store envelope (KS1000 RW), main structure deflections must be restricted to tighter limits – call Kingspan Technical Design Bureau.