Roof Scupper Sizing Calculator

Size roof scuppers for overflow protection on flat roofs.

Total roof drainage area.
sq ft
100-year storm intensity.
in/hr
Water depth above scupper opening.
inches

Results

Required Flow Rate-GPM
Scupper Opening Area-sq in
Suggested Dimensions-inches
References: Based on IPC Section 1108 scupper sizing and weir flow equations