Curtain walling and cladding

6.9.4Loads

Curtain walling and cladding systems, including brackets and fixings, shall allow movement without causing damage or deformation, and safely transfer loads to the building.

Dead loads and live loads should:

  • be transferred safely to the building’s structure without undue permanent deformation or deflection of any component
  • be calculated in accordance with BS EN 1991-1-1 and BS EN 1991-1-4, and take account of internal and external pressures, the location, shape and size of the building.

The following should be accommodated without any reduction in performance:

  • Thermally induced loading due to differential stresses caused by temperature gradients within materials or components.
  • Stresses in components and materials (these should not exceed the permissible values recommended by the product manufacturer).
  • Movement within the curtain walling or cladding.

Causes of movement include:

  • dead and live loads
  • changes in temperature
  • changes in the moisture content of components
  • freezing of retained moisture
  • creep.

Allowance for movement should be provided in accordance with the design.