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​Why are there black streaks on my roof?

Have you driven up to your home lately and seen unsightly black streaks on your roof? What are they, and how did they get there? Seeing your perfect, well-kept landscape tainted by the eyesore of black streaks on the roof can be a frustrating experience for homeowners.  
Let’s explore why you have black streaks on your roof and the best way to get rid of them!  
Why are there stains on my roof? 
Various things can cause stains on your roof. The most common include: 

  • Black mold: Black staining can be caused by fallen leaves and organic roof debris that can grow black mold. This is most common on older roofs because modern roofs get treated with a mold-resistant substance.  
  • Trees: If you have plenty of shade on your roof from big trees, it can cause moss or lichen to grow. This can cause discoloration, but it is an easy fix for most homeowners. 
  • Algae or fungal growth: Algae growth is one of the most common causes of black streaks on roofs. It occurs in humid areas, and if there is less exposure to sunlight, it’ll encourage algae growth. 


What is black algae? 

The unattractive black streaks on your roof are caused by algae called Gloeocapsa magmaThey are a group of airborne algae spores with a blue-green color and turns black when it decays. You might be wondering how these algae cause black streaks on your roof. Since black algae spores are airborne, they can be carried by wind, squirrels, and birds, travelling from roof to roof.  
Black algae need nutrients to thrive, which is precisely what the limestone filler found in asphalt shingles roofs can provide for it. The limestone granules that get embedded in the shingles will get fed on by the black algae. While manufacturers treat the shingles with copper to prevent black algae from growing, they will lose their effectiveness over time.  
What are the effects of Gloeocapsa magma? 
As the black algae feed off the shingles, it can reduce the quality of your roof. Some of the following effects of black mold include the following: 

  • The shingles can break, which will cost you money. 
  • Your roof won’t reflect UV rays as effectively driving your utility bill up. 
  • It reduces your home’s curb appeal because of the discoloration of the shingles and black streaks. 

Many homeowners don’t notice the black algae at first because the discoloration will develop over time. As the black mold begins to spread, gravity will pull it down, causing the black streaks on your roof. You’ll be compromising the integrity of your roof if you leave the condition untreated.  
If you live in Syracuse, New York, the climate is the perfect place for black algae to grow. It gets hot and humid in the spring and summer, causing black algae to spread and grow while lying dormant during the winter. 

What can I do if I have black streaks on my roof? 

You can’t control how the wind moves and where spores will land, but you can help prevent algae from forming. To prevent algae from forming, you must make your roof an environment that’s unhealthy for spores. One way of doing this is to trim back overhanging branches to increase the amount of sunlight on your roof.
Maintain your roof and gutters regularly to ensure that your roof drains excess water as intended. If you are staying in a humid area, consider investing in algae-resistant roofing materials. You can also use moisture-resistant chemicals to treat your shingles or shakes.
But what if it’s too late to prevent algae? The answer lies in treating the problem. It’s crucial that you don’t try to clean algae from your roof by yourself. Attempting to clear your roof algae with bleach and water could result in costly roof leaks or extra moisture hidden beneath your shingles. If you’re not careful, it could put your health on the line.
Roof algae repair should always be left to the pros. Treating the fungus yourself might harm your shingles by removing granules and leaving ugly bald areas.
Almost one-third of all roofs get replaced prematurely because the homeowner was mis
informed that roof stains could be removed or forgot to clean the roof, allowing mold, algae, and mildew to destroy the roof beyond repair. It’s important to remember that the stains on your roof are an environmental problem and that changing them will not stop them from reemerging on your new roof in the future.


Why you should call roofing professionals?

 A licensed roof cleaner will handle your roof algae problem in the best professional way. An expert can:

  • evaluate your roofing structure
  • identify whether the algae has caused any underlying problems
  • clean your roof safely

A exterior cleaner can then suggest strategies to avoid further algae growth, such as using specialized roof coatings or cleaning the gutters. They can also schedule repairs if algae have harmed your roofing system.
The best time to call an exterior cleaner is when you notice the following:

  • Discoloration or dark spots
  • Moss growing
  • Lichen growing
  • Large over hanging trees
  • Debris falling on roof
  • Lack of sunlight on the roof
  • Full gutters
  • Dirty siding

The following are benefits when you get CNY Roof Cleaners to clean your roof and gutters:

  • prevent damage to your property
  • prevent expensive gutter repairs
  • remove blockages and improve water flow
  • eliminate safety risks
  • prevent ice dams

When you see evidence of possible algae growth on your roof, get in contact with us at CNY Roof Cleaners. The longer you wait to cure it, the more it will leave a long lasting staining or cause damage to the roof. We can save you both time and money from having to replace the roof prematurely
We are affordable and serve within the Syracuse, New York, area. Contact us today to get an obligation-free quote, and we hope to get your gutters unblocked!