Roof maintenance. Is your roof streaking?

Dark streaks on roofs are caused by algae growth. They are more common on the northern sides or roofs with a lot of shade from trees. The algae is considered a cosmetic issue and does not harm your roof. Be careful if you need to go on your roof for any maintenance, as it may be slippery.

Don’t attempt to power wash or scrub asphalt shingles or you will remove all the granules (i.e. ruin the shingles). Algae-resistant shingles are an option when it’s time for a replacement.

For more info on cleaning and preventing this issue, see our previous blog on this topic at Roof Algae.