Find the size, and number of downpipes, and the eaves gutter size, required for any roof.
It is based on the Australian Plumbing Code AS/NZS 3500.3.
Rainfall intensities for various Australian towns can be selected, however the user can enter any intensity, enabling the app to be used anywhere.
Enter the downpipe size and find the number required, or work back the other way, by entering the number of downpipes wanted and find the size, along with the associated eaves gutter size.