Site Management

The effectiveness of clearances in achieving durability requirements is subject to the occupant ensuring that vegetation, debris, and soil do not build up against the cladding surface. Design clearance from a surface is no guarantee of durability as effective clearances are subject to site development, occupant behaviour and building maintenance.

Cladding Open to Air
 

Cladding open to air

Cladding which is open to air will experience the normal wet/dry cycles for which it is designed.

Vegetation in Contact with Cladding

Vegetation in Contact with Cladding

Vegetation or earth in contact with the cladding will increase the time of wetness and may contain corrosive compounds.

The separation of profiled metal claddings from corrosive surfaces such as wet timber or concrete is more critical at the bottom end of cladding, where high humidity levels may be experienced for extended periods. This may take the form of a 3 to 6 mm gap, an inert self-adhesive tape or a PVC vermin strip.

Internal environments are also important, ventilation must be adequate for the building use, and absorptive of corrosive substances must not be in prolonged contact with the external or internal face of the cladding or structure.

The Result of Debris Build-up Against Cladding

 

Corrosion due to build-up

Allowing build-up of material against wall cladding can result in corrosion regardless of nominal ground clearance.