Cleaning a Metal Roof

ISSUE

Particularly in dirty environments, there can be instances when it is desired to clean an existing metal roof. In order to accomplish this, certain precautions must be taken for personal safety and to avoid damaging the roof.

ANALYSIS

Many metal roofing contractors offer roof cleaning services to past customers. If, in order to clean the roof, the cleaner must be on the roof, homeowners are advised to have an experienced contractor perform the work. In any event, manufacturer’s instructions for walking on the roof must be followed. If cleaning cannot be accomplished from a ladder or perhaps from a bucket truck, roof access can be made safer by laying walk boards on the roof or hanging ladders from the ridge and using ladder jacks to support walkboards between them. Metal roofs can be cleaned with brushes or by power washing. A cleaning solution consisting of water, detergent such as Tide, and (optional) trisodium phosphate such as Soilax can be beneficial in cleaning the roof. If the roof is power washed, take care to avoid high pressure spray directly into interlocks and overlaps of the metal roofing panels and flashings. After cleaning, the roof should be rinsed thoroughly with clear water before it dries.