Brian C. Jackson services New Hampshire and Massachusetts for non-pressure / soft wash roof cleaning. Homes through out new England are covered with a black staining and this staining is an algae call gloeocapsa magma. This algae can and will shorten the life of the roofing shingle and the roof will need to be replaced earlier than expected if the algae is left to feed on the roof. Derry , New Hampshire 03038 is like all of the other towns in New Hampshire and the homeowners want there roofs cleaned and cleaned properly. The ARMA (Asphalt Roofing Manufacturers Association) recommends and approves of a non pressure / soft wash roof cleaning method and does not approve the use of a pressure washer or a power washer. The use of a high powered machine can and will damage the granules on the shingle and is some cases may void the warranty on that roof. There is no need to clean a roof with high pressure and I have attached a few before and after pictures to view and this roof was cleaned with a non-pressure soft wash application. For more info on roof cleaning or any of the other soft washing services we provide just visit www.jacksoncontracting.net or call Brian @ (603)401-8408.