It is a golden rule that a roof will serve longer if there is a good rain drainage system installed . When rain water is able to drain from the roof , it does not gather on the roof and does not erode it. But as we said previously, debris gathers not only on the roof but also in the drainage system. So this system as well as the roof must be kept clear of debris This will help to ensure that the rain water will not does not damage the roof.
Finally, moss and other plants on the roof is a very common problem, especially in rural areas, where there is a lot of natural dust which gathers on the roof and provides a seedbed for moss. If moss starts to grow on the roof , it should first be cleaned with special anti-moss liquids and then cleaned with a power hose. It is recommended that this be done regularly so that the moss does not get a hold on the roof.