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Giving Your Roof its Maximum Life Expectancy

Updated: Oct 14, 2022

Growths Under Open Sky
Half Cleaned Roof

When you purchase a new home generally you should have 20 to 30 years before you need to replace the roofing shingles. What is often overlooked is the fact that a 20-year shingle must be properly maintained to reach its full lifespan. This means that you must have your roof cleaned every three to seven years as recommended by The Asphalt Roofing Association (ARMA). Roof Algae, for example, can significantly reduce the life of a roof, and can completely cover a surface in as little as four years when the conditions are right for growth. What is more, insurance companies who underwrite homeowners' policies as well as the shingle manufacturers themselves (who enforce product warranties) both explicitly require that roofs be cleaned using accepted practice, i.e., bleach mixture and proper agitation methods. This kind of cleaning is risky and professionals should be trained to manage those risks effectively.

Pressure or Soft Washing According to Surface

Certain types of algae, moss, bacteria, lichen, mold, and mildew grow in shady damp settings. A situation where there is a tree canopy is an obvious issue, but such growth also occurs with roofs that are out in open fields, without shade. Michigan, for instance, has many cloudy days during winter, early spring, and late fall. A string of cloudy days is all it takes to get growth going on your roof.


Asphalt shingles, in particular, contain limestone filler which is a preferred nutrient for algae spores. The spores themselves are naturally occurring and move about with the wind. Essential maintenance includes frequently removing dead leaves from the roof valleys and gutters. This action alone will help reduce the seeding of such growths on your shingles. All you need to remember is that the biosphere (the world of invisible or tiny organisms) includes many types of critters which can harm roofing when left to do what they do. Happy Window Cleaning is the only local pressure and soft washing cleaning company that has an IICRC certified microbial remediation expert at the helm.

Why does that matter, I mean it’s just cleaning, right?

Who cleans, and “how” matters. It’s important because the organisms which affect roofing have different physical properties. For example, sometimes cleaning people mistake common lichen, (Which are two different microbes that live together and depend on each other), with roof algae (A photosynthetic bacteria named “Gloeocapsa Magna”).

While the former offender presents its own set of unique problems for the roof, the latter duo actually has a root system that attaches itself to the shingles. That makes lichen particularly tricky to remove without harming the roof itself! When left unattended lichen will, for sure, destroy your roof in short order. The bottom line is simply this; for you to get 20 years from a 20-year shingle, you must properly maintain your roof, which in this case means that the best and safest thing to do is to call your hometown certified professional. Call Happy Window Cleaning for a free estimate/consultation.

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