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What causes black streaks on roofs

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Why are black streaks appearing on your roof?

The black streaks on roofs are a type of algae called Gloeocapsa magma.  It usually starts as a blue-green algae and as it matures it develops a dark, hardened outer coating, which results in the black stains you see.

The black stains caused by this algae will worsen and become more noticeable each year, trapping moisture and causing premature shingle aging and granule loss.  If you don’t like the black streaks, they can be cleaned using professional grade roof cleaning solutions.

Roof Cleaning And Black Stain Removal Services By PowerWashCompany.com

The Black Stains from Gloeocaspa Magma are unsightly and therefore affects the curb appeal of any property. The dark stains place an added load on air conditioning systems as well. As this bacteria feasts on the components of shingles, ultimately it invites moss and lichen and algae to infest the structure of the roof material and cause premature failure of the roof. It has been estimated that as much as 50% of all roof replacements have been done because of the appearance of the roof and not actually because of its functionality.

Professional Roof Cleaning Services
PowerWashCompany.com has provided exterior building cleaning and other pressure washing services for over 30 years. However, over the last five years, we have seen a huge increase in roof cleaning services by other contractors, and most of them are untrained and inexperienced. This is dangerous for employees working on rooftops 40 feet in the air, as well as dangerous for the building surfaces and roofing systems when these employees use high pressure cleaning methods.

Before hiring a roof cleaning company, make sure they understand the basics of roof installation and that they have taken some type of Industry Training for roof cleaning to learn how to clean roofs.  It is also equally important that your roof cleaner is familiar with the function of all roof structures to avoid causing mechanical damages and leaks.

Roof Cleaning And Roof Washing Services In Maryland, Virginia And Washington DC


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