Flashings For Horizontal Corrugate Cladding

The designers should remember that horizontal cladding produces increased shadowing and that most colours will show the accumulation of dirt. The ribs of deeper, longer spanning profiles will collect dirt both inside and outside the building, particularly on the unwashed areas of the flashings and on the underside of the ribs of outside cladding.

Insulated lined walls which are externally clad with horizontally fixed metal sheeting without a cavity should have some provision for ventilation. The better alternative is to use cavity construction.

All cladding requires maintenance, and as horizontal cladding and flashings are not self-cleaning by rain, it needs frequent washing to maintain the durability required by the NZBC, appearance and the requirements of any warranty. See Maintenance.

The maintenance schedule should be provided to the owner in writing. Owners should be made aware that horizontal cladding is particularly susceptible to damage by ladders that are used without spreader bars, and it is their responsibility to notify window cleaners.