Many people don’t ever think about that fact that like many other items on the inside and outside of their home, their roof needs to cleaned as well. Not only does it need to be cleaned for appearance sake, but in order to prevent the lifespan of your roof. But why, you might ask.
If you begin to black spots anywhere on your roof, it may be a cause for concern. From a distance, this could look moldy or streaky however, neither one are quite what it is. These black spots and streaks are actually algae colonies that form in and on top of your shingles, and feed on the limestone filler agents and moisture. Most shingles are treated with a algaecide and typically keep this kind of algae from showing up for around 10 years.
Once it finally does wear off, your roof essentially becomes a possible target for housing these pests. It gets even worse from here though. Eventually, these algae dig deeper into the asphalt (or other roofing material) and eat away at the light reflecting granules of your roof. Needless to say, the problem is almost out of hand at this point and a new roof could be the only option.