How to Remove Black Streaks from Your Roof

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As a top provider of professional roof cleaning services in the local area, Puget Power Washing receives hundreds of questions about lichen, algae, and mold infestation. Seattle’s residential and commercial property owners want to know about solutions. Can they pressure wash their roofs, and are moss treatments worth it?

Whether you are thinking about hiring a gutter cleaning service team or the next spring cleaning project, removing black streaks from the roof should be high on the list of things to do. In this article, our roof cleaning experts explain why these stains appear and why it is important to eliminate them early.

What Are The Black Streaks on the Roof?

Black streaks appear on roofs continuously, whether it is a historic landmark or a newly remodeled addition to the neighborhood. It looks dark and menacing enough from far away, but under a magnifying glass, it is blue-green and benign. These black streaks come from the growth of gloeocapsa magma, also known as algae.

How Can Property Owners Protect The Roof?

An algae removal service is part of our local roof cleaning services. The city’s proximity to Puget Sound makes it a high-growth area for black streaks of algae, no matter how resistant or durable the roofing material is. Without regular removal, these black streaks spread unabated and eventually present a myriad of problems.

Can These Black Streaks Destroy A Roof?

Yes, but according to the Asphalt Roofing Manufacturers Association, algae streaks will not present a long-term structural challenge under a periodic maintenance schedule. The limestone fillers in roof shingles attract algae growth. If left for too long, it eats through the protective layer and causes damage.

The digestive properties of algae on limestone are not the only concern, however. Algae streaks can heavily downgrade the curb appeal of a property, especially on the roof. Algae infestations make roofs look run down, but regular removal can be affordable with professionals like Puget Power Washing.

How to Safely Eliminate Algae from A Roof

The Puget Power Washing team uses two primary techniques: pressure washing and soft washing.

Washing Roof Surfaces with Pressure Washers

High water pressure can remove algae, but too much pressure will also wash away the stone granules so vital to the roof’s shingles. The mistake could destroy a roof after only a few cycles, which is why we only recommend this technique on certain types of roofs. Soft washing is a much safer option for most properties with less durable roofing materials.

Cleaning Roofs Using Soft Washing Techniques

A bleach-based technique is a top tool for roof cleaning. This ‘soft-wash’ approach can eliminate bacteria, algae, and fungi effectively. Professionals like us might use these solutions in a sound maintenance routine (where we have cleaned the gutters and rinsed off other debris).

Most commercial roof sprays are water and bleach combinations with additives. It is often a good idea to suggest that neighbors soft wash their roofs in sync with yours to prevent the algae from their roofs blowing into yours after it is clean.

Work With Your Local Roof Cleaning Professionals

Most homes and businesses in Seattle are only a few miles away from Puget Sound. The climate causes a host of roofing problems in spring and summer with rising humidity levels.

Don’t wait; call Puget Power Washing at 206-701-9280 today and ask us about our cost-efficient roof cleaning services in your area.

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