Flashing Cover 5.2.1

The flashing cover of a cladding rib height of less than 20 mm is insufficient to ensure weathertightness.

When a parapet wall extends above the apron it can cause additional turbulence, and will also increase the water catchment and in these areas . O ne rib cover or 150 mm is regarded as insufficient to weather either a longitudinal or transverse barge or apron flashing.

When ribbed or trapezoidal roof cladding finishes at the wall or an abutment, the aesthetic appearance of a longitudinal narrow single rib apron flashing may be unacceptable and in these cases the cover should be increased. Cover dimensions for claddings other than profiled metal are given in Flashing Cover.