Exterior Pro Wash is your Guaranteed Safe, No-Pressure Roof Cleaning Company.  We use only the highest quality, bio-degradable detergents and the most effective and safest cleaning practices.  As experienced professionals, we believe in continuing education, industry certification and providing our clientele with informational articles from peers within our industry who’s cleaning processes mirror our own.

Taken from our Industry Publication:  UAMCC, Issue #2 Roof Cleaning

A roof is the top line of defense against the elements, notably rain but also wind, animals and heat. Roof damage can become expensive and the last thing anyone wants is an unexpected bill. Gloeocapsa magma is growing on the roof – just because you can’t see it yet, doesn’t mean it isn’t there.

Asphalt, tile or metal roofs are not immune to this invasive pest that appears to be dark stains creeping up the roof. Gloeocapsa magma is a species of cyanobacteria. Cyanobacteria are an ancient line of photosynthesizing bacteria, which photolysis water generating oxygen gas. Ancient cyanobacteria are ancestral to the chloroplasts of all plants on earth. All this bacterium requires to grow is water and sunlight, which enables it to grow any and everywhere.

We live in nature and nature keeps trying to take back over– look up sometime and you will see the visual evidence. This bacteria grows like an algae on your roof, it feeds off of moisture and sun. The first picture shows a healthy asphalt roof shingle without any infestation. This shingle is healthy, dry and is protecting the house underneath.
roof-cleaning-uamcc1Comparatively, the second picture shows the same shingle that has gloeocapsa magma. It looks degraded and thin, not the top layer of defense a roof is supposed to be. Moss and lichen will now grow on top of the algae, putting roots into the shingles around the granules. You will start to see green splotches pop up all over. The roots are disrupting the shingle composition more quickly than necessary.


The goal, here, is to kill the infestation and to leave as many granules as possible on the roof. The first step is to do some research: Read the roof warranty – choose a method that will not void that warranty. If you have a warranty that covers treatment for algae, moss and lichen great! It can be difficult to obtain a check, but it won’t hurt to call and find out. The Asphalt Roofing Manufacturer Association and other roofing manufacturer publish technical bulletins with specifications particular to their product.

The right contractor will be familiar with the method the manufacturer recommends and will be able to explain their cleaning process in detail.                                             – Morgan Booz, AccuWash