Abstract: A roof flashing unit which is attachable to a parapet or other upstanding wall at its intersection with a roof to ensure a tight, waterproof roof construction. The unit includes a rectangular sheet of bendable metal having a transverse Z-shaped bend therein to define an upper or counter section which is secured to the wall and a larger base section. The diagonal of the Z bend forms with the counter section are open-ended channel, and it forms with the base section an open-ended pocket. Wedged into the pocket is the upper edge of a flexible waterproof membrane which overlies the base section.