#### SMACNA Downspout & Gutter Calulator

SMACNA Downspout & Gutter Calculator ... The capacity of a sloped rectangular gutter may be approximated by using a gutter cross section area not less than that of a semicircular gutter and a depth to width ratio of at least 0.75. ... of a sloped rectangular gutter may be approximated by using a gutter cross section area not less than that of a ...