Worthington home new roof

If you start noticing black streaks or stains on your shingles, you might start to worry. Here are some tips from Muth & Company Roofing to help you know how to address those dark spots on a roof.

dark spots on your roof

The cause of dark spots on a roof

At first glance, those dark streaks and patches may look like dirt. The most common culprit is black or blue-green algae. The spores are transferred onto a roof by the wind, and if warm, moist conditions exist, algae will begin to grow.

Shingles that contain crushed limestone, which is a great food source for algae, will also promote algae growth. Ugly spots of dark discoloration remain when the roof dries and the algae go dormant.

Algae-resistant roof shingles

If your roof needs to be replaced, the permanent solution to algae woes is to have Muth & Company install GAF algae-resistant shingles for you. These shingles contain copper or zinc, which are poisonous to algae.

We also recommend the installation of zinc or copper strips across the roof. The installation is every eight to 10 feet up, to help prevent future growth. The rain actually activates the metals and further distributes the poison over the roof!

Removing algae stains

Roofs can be dangerous, especially when wet and slippery, so let one of Muth & Company’s roofing contractors in Columbus, OH, recommend an option for cleaning or a local company that specializes in roof cleaning. We avoid power washing, as this can dislodge granules off the shingles. Keep in mind that some stains may not be able to be removed completely, so Muth & Company cannot guarantee a completely clear roof after cleaning.

If you think you need to schedule an inspection, cleaning, or roof replacement, or want to find out more about algae-resistant shingles, contact a professional at Muth & Company Roofing. We’d be happy to provide more information and a FREE estimate.

Need the best roofing available in Columbus, OH, and surrounding communities? We’re the roofer who wants to earn your business. Call Muth & Company Roofing today at (614) 882-0900 for a FREE estimate, or fill out our contact form. We serve Columbus, Westerville, Delaware, Worthington, Dublin, Bexley, Gahanna, New Albany, and many other surrounding Central Ohio cities.

Scroll to Top