Treating all roofs using a selection of chemicals appropriate for your roof cladding. The treatment will kill lichen, moss, algae and mould within weeks. The growth will then take a period of time to weather off in the sun, wind and rain. Every cladding has a different weathering off period as some roof cladding holds the growth more than others due to its design and texture.
If you collect water off the roof, you must disconnect your water tanks before the treatment. They must remain disconnected for a minimum of 4 weeks and there must be rain during this time, a minimum of 32 mm rainfall. Roofs with heavier growth are to be disconnected for a longer period of time with a minimum 38 mm of rainfall.
This is the safest approach to cleaning and maintaining your roof.