Moss, algae and lichen do more than make a roof look tired. They hold moisture against the tile surface, freeze and thaw through winter, and progressively degrade the cementitious surface of concrete tiles. Chunks break off gutters, block downpipes, and cause the exact overflows that lead to fascia and wall damage.
White Horse Roofing carries out roof cleaning, manual moss removal, soft-wash biocide treatment and protective coating across Oxfordshire, Berkshire and the Cotswolds. We do not high-pressure wash — the damage it causes to tiles far exceeds the cost of doing the job properly.
Who it's for
Homeowners with a visibly moss-covered roof — clumps in the gutters, green streaking down the tiles, black algae staining. Owners preparing a property for sale who need the roof to present properly. Landlords with tenant reports of overflowing gutters that turn out to be full of moss.
When it's needed
When moss coverage is visible from the ground, when gutters are repeatedly blocked by fallen material, or when tiles are showing green or black streaking. Ideally treated before winter, when frost cycles in wet moss cause the most damage to the tile surface.
Why professional
Roof access at height, chemical handling of soft-wash biocides, and the discipline not to reach for a pressure washer. High-pressure cleaning strips the surface of concrete tiles, removes the granule coating from slate, and forces water under the tiles into the roof structure — a common cause of leaks after DIY jet-washing.