Façade cladding and fire resistance

A zinc facade built up is normally ventilated. As a result, the materials used are directly exposed to fire via the ventilating cavity.

All individual materials, which usually have different fire classes, must at least comply with fire class D.

In the event that a façade has to comply with fire class B, only the wooden structure (timber boarding)  does not meet these requirements. As an alternative to these timber boardings, an aluminium trapezoid panel (or galvanized steel panel with coating) with an aluminium supporting structure can be applied. Wood structures treated with fire retardant can also be used. Check if the fire retardant can be used in combination with the zinc material.

The assessment with fire safety of a façade has to be done by an expert on the basis of EN 13501-1.

 

Option 1:      Façade structure with rear ventilation.

 

A facade built up of a NedZink standing, roll cap or lozenge system is normally supported by a wooden substructure.

The materials used have the following fire classes (from outside to inside):

  • zinc standing seam, roll cap or lozenge system:                           fire class A1
  • unplaned, untreated timber boards thickness 22 mm:                   fire class D
  • unplaned, untreated supporting rafters min. thickness 25 mm:     fire class D
  • ventilating cavity (depth depends on cavity thickness)
  • damp control course fire-resistant                                                  fire class B
  • insulation material with minimum                                                   fire class D

The supporting rafters can be replaced by an aluminium supporting structure.

 

Option 2:      Façade with a ventilating aluminium support construction.

An aluminium support construction is used for a NedZink Composite facade:

The materials used have the following fire classes (from outside to inside):

  • zinc cassette system:                                                         fire class A1
  • aluminum facade profiles as supporting structure:             fire class A1
  • ventilating cavity (depth depends on cavity thickness)
  • damp control course, fire-resistant                                     fire class B
  • insulation material with minimal                                          fire class D