Roof Drainage System Design

From the very dawn of building construction it has been necessary to incorporate some method of gathering and discharging rainwater from the roof of a structure.

Roof drainage system design.

Roof drainage is one of the fundamental considerations of building design. Design considerations to keep in mind. The design event used for sizing a roof drainage system will therefore not normally come out of a clear blue sky and then end equally suddenly but will have been preceded by a period of less intense rainfall. Functioning drainage system for steep slope roofs is to maintain a minimum roof slope.

Establishing a minimum slope is critical because most steep slope roofing as. There are various approaches that can accomplish this balancing act but each offers its own advantages disadvantages depending on a number of factors. Typically a steep slope roof slope is equal to or greater than 3 inches of rise per 12 inches of run 25. For most dwellings you ll find that gutters range in size from approximately 100mm diameter to 150mm diameter assuming gutters with a half round section profile and downpipes range from approximately 60mm diameter to 90mm diameter assuming circular downpipes.

Hence this is by far the most common roof drainage situation.