Internal Roof Drainage

Roofs of this design will have one or more roof drains or scuppers installed.

Internal roof drainage.

If water collects in one spot in the middle of your roof then installing an interior drain there to move the water is a good solution. Watch for clogs blockage at the roof drain or scupper. The most important factors in roof drain design are. Unlike scupper or gutter drainage systems in which water flows off the side of the roof internal systems allow for drains to be strategically placed throughout a roof deck to ensure water doesn t pool.

On large flat roofs mainly on commercial buildings or large residential complexes you ll likely find internal drainage systems. Internal roof drains these will drain to somewhere near the center of the roof and down through the building to underground storm mains or a detention pond. Properly locate roof drains scuppers and gutters to remove water from the roof s surface. The drainage requirements for flat roofs on buildings present some special problems that we describe and illustrate here.

This form of roof drainage is preferred if a clean exterior appearance is desired. Properly slope the structural framing and deck minimum inch per foot. Use an insulating fill or tapered insulation for slope. At page top and at left our photos show a low slope roof surrounded by a parapet.