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What Are Those Black Streaks On My Gutters?

What Are Those Black Streaks On My Gutters

Black streaks on your gutters aren’t something you should take lightly. When not removed, they can affect your curb appeal and spread to other parts of your home. You might be curious about what they are and how to eliminate them if you’ve noticed them on your gutters. 

What Are Those Black Streaks On My Gutters?

Professional gutter contractors share the possible causes of this issue and some prevention tips. 

What Causes Black Streaks on Gutters?

Usually, black streaks form on gutters due to excessive debris. The buildup of twigs, leaves and other organic materials creates the ideal environment for mold and mildew growth. 

Another reason this issue occurs is due to excess humidity and airborne pollutants. Humid air will cause condensation on the gutter’s surface. When combined with dirt, pollen and grime, moisture will cause black streaks to develop on your gutters. 

A leaking gutter system is also more likely to have black streaks. It’s a common problem in sectional gutters. Seamless gutters are not as vulnerable to leaks that can later cause black stains. That’s because seamless gutters have fewer nooks and crannies where debris can settle. 

How Do You Prevent Mold and Mildew Growth on Gutters?

You can do several things to prevent mold or mildew from growing on your gutters and creating those unsightly black streaks.

  • Keep gutters clean of debris. Regularly remove leaves, twigs and other debris from your gutters. Doing so will prevent a buildup of organic matter that creates an environment conducive to mold growth.
  • Inspect gutters regularly. Periodically check your gutters for signs of leaks, cracks or holes that could allow water to enter and promote mold growth. 
  • Install gutter guards. Gutter guards help keep leaves and other debris out of your gutters, reducing the risk of mold growth.

How Do You Deal With This Issue?

If you already have black streaks on your gutters, you have some options to remove them. Power washing with bleach will kill any bacteria that could be causing the streaks and will leave your gutters looking new. You can also use a garden hose with a spray attachment to rinse away dirt and grime.

If you’re looking for a way to prevent black streaks from forming on your gutters or need help removing them, contact Advantage Seamless Gutters. We offer professional gutter cleaning and repair services that can keep your gutters looking their best. Call us at (218) 270-2663 or fill out our contact form to schedule a free estimate. We serve clients in Baxter and Brainerd, MN.