The Design of Conventional and Siphonic Roof‐Drainage Systems

Abstract

Abstract The hydraulic principles governing the performance of conventional and siphonic roof‐drainage systems are described and compared. The flow rate in a conventional system is determined by the depth of water in the gutter or on the roof. Siphonic systems are able to achieve higher flow rates because they make full use of the head available between the roof and the discharge point at ground level. Some special operating characteristics of siphonic systems are described and recommendations are made on the factors that should be considered in their design.