Industry experience and field testing suggests that the amount of water diverted should be determined based on (1) the surface area of the roof, and (2) the amount of  pollutants on the roof.

The following factors can be used as a guide in determining the volume of water to be diverted.

The Diverters are sold in kit form and incorporate standard 90, 100 or 300mm PVC pipes as the diverter chamber section. The length of pipe used will vary depending on the volume to be diverted.

Diverters with a variable volume chamber are better than fixed volume diverters because the volume of diverted water can be customised to the specific requirements of each roof.