Smacna Gutter And Downspout Sizing

The sheet metal and air conditioning contractors national association smacna is an international trade association representing 3 500 contributing contractor firms.

Smacna gutter and downspout sizing.

Gutter sizing per smacna. Now architects engineers designers and contractors can easily and accurately size downspouts and gutters according to the specifications in smacna s architectural sheet metal manual 7th edition 2012. The sheet metal and air conditioning contractors national association smacna is now providing a simple and effective downspout gutter sizing calculator. This application runs the equations laid out in the smacna handbook.

In response smacna s technical resources department has created a free downspout and gutter sizing calculator. To limit the effects of thermal expansion in gutters 50 ft. 15 m is a practical maximum gutter length to be served by a downspout. The downspout and gutter sizing calculator is located on the tools cad and apps page of the smacna website.

Smacna notes that one of the most frequently asked architectural questions the association receives is about sizing gutters and downspouts. It should be used to calculate required gutter size downspout size and downspout spacing for a given roof area. Smacna s downspout and gutter sizing calculator one of the most frequently asked architectural questions smacna receives is on sizing gutters and downspouts. 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.