Does Your Roof Have Streak Marks? Know How To Combat Algae

When your home is the only one on the block with black streak marks on the roof, it will look bad in comparison. Thankfully, these marks can be removed to make the roof look clean once again. Here is what you need to know about removing and preventing streak marks.

Streak Mark Removal

The reason that you have streak marks is because of algae colonies. It happens because algae feeds on moisture and limestone filler on your roof's shingles. If you do not clean off the algae, it will consume the limestone on the shingles, then start deteriorating the asphalt material.

Using a cleaning solution for your roof that contains sodium hydroxide will get rid of the algae. You want to avoid using bleach, since it is a corrosive material that can discolor the roof in a different way.

When you're ready to clean the roof, pick a day that it's overcast with little wind. This is because you don't want the sun causing the cleaning solution to dry up before it can work into the shingles. This is very important when dealing with black algae, so the more clouds the better.

Before you can begin, you'll also want to repair loose shingles and clean your gutters out. Cover any vegetation near your home with plastic, and move your outdoor furniture away from your home. The cleaning solution won't damage these items, but it will save you the hassle of needing to clean them afterwards.

With the prep work finished, cleaning your roof is as simple as following the directions provided on the cleaning solution.

Streak Mark Prevention

Algae tends to return if you don't take preventative steps to stop it from coming back. You can do this by having a metal roof cap installed. It's placed at the peak of your roof, and when it rains, it causes copper to travel down the surface. The copper will kill any algae with the rain, preventing it from getting out of control and forming streak marks.

Another method is to use to use a sealant that provides a protective coating to the roof. It will need to be reapplied after a couple of years, but is an effective way to prevent algae growth.

For more information on algae prevention to avoid those unsightly black marks, reach out to a local roofing contractor. They can help assist with both removing the stains and installing preventative measures. For more information or assistance, contact companies like