When the roof is completely surrounded by parapet walls and drainage depends on scuppers or internal drains, it is recommended that over-flow scuppers be provided.

We supply thousands of over-flow scuppers to production home builders annually. Order one or one thousand.

Fig A shows a cross section of an overflow scup per in a masonry wall. The scupper is delivered to the job site with the roof side flange attached.

It is inserted in the masonry wall and the outside flange is attached (Details 1 and 2). Where the top of the outside of the flange joins the wall, this junction should be sealed.

Fig B pictures the scupper and shows a counter flashing over the roof side flange. This flange extends 4 in. onto the roof cant.