One of the most frequently asked questions by homeowners seeking answers to their home repair and maintenance needs is why their asphalt shingles roof has black streaks and possible ways to remove them. Those black streaks on your asphalt shingles roof are algae.

Gloeocapsa magma – also known as blue-green algae, these algae are microorganisms that grow on shingles. They start growing as tiny spots and develop into becoming visible streaks. It takes about two to three months for small streaks to grow and develop into a visible black streak pattern on your shingles roof.

These black streaks on your roof may look like dirt, mildew, or mold. However, they are algae that are capable of eroding the quality of your asphalt shingles roof. The algae appear to be black because Gloeocapsa has the potential to form a shielding, dark-colored outer covering.

The blue-green algae use this dark pigmented outer coating to guard against damaging ultraviolet rays from the sun. Though algae can be found on any roofing, it is most commonly found on asphalt shingles roofs.

Why do algae appear to be black?

Gloeocapsa, blue-green algae can form a darkly pigmented outer coat; this coating shields the algae from damaging ultraviolet rays. That is why your roof looks unattractive. Although algae can be found on all types of roofs, it is prevalent with shingles roofs.

Why does my asphalt shingles roof have algae

The primary means of transmission of algae spores is by air. The fact that they are airborne makes the level of spread from one roof to another very rapidly. Algae spores are also spread by animals and can also stick to the clothing of humans. Before now, most asphalt shingles were made mainly from asphalt.

As a means of cutting costs, most shingles manufacturers started producing shingles from packings such as fiberglass and grated limestone coupled with asphalt. The crushed limestone filler stimulates the growth of algae because they directly feed on it. Another major factor that causes the growth of algae on asphalt shingles roof is the weather. Algae growth is higher in a warm and humid climate.

Nevertheless, algae growth on shingles roof is common in cold regions because they also share humid summers. Overhanging trees are also a contributing factor to algae growth on the shingles roof. Algae thrive in shaded and damp areas. Overhanging trees causes damp surfaces on the roof as it hinders the sun from drying up certain areas of the roof, thereby creating a breeding ground for algae.

How to eliminate black streaks on your roof

You can get rid of the black streaks on your roof by carrying out simple roof cleaning. The best method of removing algae on asphalt shingles roof is soft washing. Spores of algae can be eliminated by soft washing, thereby preventing their further growth.

However, specialized cleaning solutions like chlorine bleach and water can be effective in delivering excellent results. Please avoid the use of pressure washing as it can damage shingles by forcing the protective coating of the shingles to break off. You can employ the services of professional roof cleaning services to get the job done correctly.

Contact us today at Alvarez Power Washing for a free quote! (973-651-8225)