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What Are the Best Algae-Resistant Shingles?

January 15th, 2025 | 5 min. read

What Are the Best Algae-Resistant Shingles?

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Are you tired of seeing black streaks on your roof? Is preventing them from forming a big factor for you when choosing a shingle?

Black streaks caused by algae growth have become something the roofing industry has taken head-on. Now, manufacturers focus on making algae-resistant shingles to help keep your roof looking great for as long as possible. 

But what are the best algae-resistant shingles? The answer isn’t as straightforward as you may think. 

For over 30 years, Bill Ragan Roofing has taken pride in helping homeowners pick the right shingle or roofing material based on their specific wants and needs. So, let’s dig into algae-resistant shingles and what you need to know about them. 

By the end of this article, you’ll have the answers to the following questions:

  • What are the best algae-resistant shingles?
  • How long do shingles stay algae-resistant?
  • What else can you do to prevent algae growth on shingles?
  • Can you clean algae off roof shingles?

What are the best algae-resistant shingles?

Many manufacturers have started adding algae-resistant properties to their shingles, so giving you a list of the “best” isn’t the right way to answer the question. On top of this, picking a specific shingle can’t be done based on algae resistance alone. 

However, there are brands that lead the industry with their algae-resistant technology. Let’s look at the shingles with the best algae resistance in residential roofing. 

CertainTeed StreakFighter®

CertainTeed applies its StreakFighter® algae resistance to all shingles in some capacity. This granular blend applied to the shingles consists of a ceramic pigment coating with a naturally algae-resistant copper layer around a mineral core. 

The copper filters out gradually to provide long-term protection against algae growth. In my opinion, CertainTeed has the best overall algae-resistant shingles across all manufacturers. 

GAF StainGuard™

StainGuard™ is GAF’s proprietary time-released algae resistance technology applied to their shingles. The shingles contain copper microsites in their granules that release copper efficiently as the years pass for long-lasting resistance to algae growth.

There are three different levels that determine how resistant a shingle is:  StainGuard™, StainGuard Plus™, and StainGuard Plus PRO™. GAF labels their shingles, so look for the Plus or Plus Pro labels to determine which of their shingles has the best algae resistance. 

Owens Corning StreakGuard®

Owens Corning’s StreakGuard® technology is applied to all of their shingle lines using granules. Like CertainTeed, the formula consists of ceramic coated around copper-lined granules applied to the shingles to release gradually over the years. 

The only big difference is that Owens Corning gets their granules from 3M, a leading producer of roofing granules. 

Atlas 3M™ Scotchgard™ Protector

Atlas uses a proprietary blend of 3M’s Scotchgard™ brand containing granules with algae-resistant copper, zinc, and magnesium. However, only four of their shingles come with it. 

Their other shingles have standard algae protections, but not the Scotchgard technology. Fortunately, they at least have a label so they’re easily spotted. 

Just know I personally do not like Atlas shingles, but the algae resistance on some products is worthy of a mention here. 

How long do shingles stay algae-resistant?

Algae-resistant isn’t the same as algae-proof, so black streaks forming are possible. How quickly they form also heavily depends on where you live, the climate, and the things around your roof line. 

So, it’s not really possible to say exactly how long a specific shingle is algae-resistant. Fortunately, manufacturers provide algae warranties for a certain length of time. 

Depending on the warranty, shingles are considered algae-resistant for anywhere from 10 to 20 years. However, most long-term warranties require installing specific accessories with the shingles. 

On top of that, some are limited and get prorated after a certain number of years. So, make sure you talk more to your roofing contractor about the specifics to get a more accurate answer. 

What else can you do to prevent algae growth on shingles?

The best way to prevent algae growth is by investing in algae-resistant shingles with long-term warranty protection. Especially the shingles that contain copper or zinc granules that are released gradually to prevent algae from taking hold.

However, there are other things you can do to help prevent or prolong black streaks for as long as possible. Another effective way is to install copper or zinc strips along your roof ridge. 

As rain goes over the strips at the ridge, small amounts of metal ions flow down with the water, which acts as a deterrent. Getting the algae-resistant ridge capping that goes with the specific shingle will also do this. 

Less expensive ways are trimming overhanging tree limbs back and keeping your gutters clean to prevent excess moisture buildup. This gives algae less of a chance to take hold on the shingles in the first place. 

Can you clean algae off roof shingles?

As I’ve said, algae growth is possible once the resistance period is over. However, this doesn’t mean the shingles are no longer effective. 

Instead, you can clean black streaks off your roof until it’s time for a roof replacement if the look bothers you. The best way to clean your roof is by simply following the advice of shingle manufacturers. 

According to the Asphalt Roofing Manufacturers Association

“The most effective method of cleaning algae and moss from a roof is with a 50:50 mix of laundry strength liquid chlorine bleach and water. Apply with a sprayer and allow the solution to dwell on the roof surface for 15 to 20 minutes, and then rinse thoroughly with low pressure water.”

Keep in mind that bleach solution can discolor your shingles if it’s too strong. So, some roofers and homeowners buy non-bleach roof cleaning solutions. 

The most important thing to avoid is pressure washing your roof. This damages shingles, blows their protective granules off, and voids any warranties. 

So, I recommend hiring a professional roof cleaning company that knows how to softwash the correct way if you want to get rid of the black streaks. 

What shingles should you consider in 2025?

After reading this article, you know what you need to know about algae-resistant shingles and what to do about algae growth. If unsightly black streaks bother you, look for the appropriate label and talk to your roofing contractor. 

But remember, you can’t really choose a shingle based on its algae resistance alone. Picking the right shingle is a huge decision that impacts everything for your future roof, from pricing to how long it lasts. 

Luckily, there are plenty of options out there. However, there are some I recommend for their superior quality, warranties, lifespan, and more. 

That’s why I wrote another article breaking down the specific shingles to consider right now in 2025. 

Check out The 6 Best Shingles to Consider for 2025 to ensure you make a great choice for your upcoming roof replacement.

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