Roof drainage systems should be designed and detailed by a suitably qualified trade or professional in accordance with the BCA and the Australian Standards. Particular reference should be made to the correct sizing of gutter; quantity and placement of downpipes; and the provision of appropriate overflow devices.
In the design and detailing of a roof drainage system, consideration must be given to a range of factors such as:
- rainfall intensity
- roof catchment area
- gutter size/capacity
- gutter fall
- gutter outlets (sumps, rain heads, nozzles)
- downpipe size, quantity and placement
- overflow consideration
You can view information on the design of roof drainage systems in the brochure for your state:
