Is your roof covered in black or bluish-green streaks? It’s an absolute eyesore, and you definitely don’t want those streaks around for longer than necessary. Algae is common on roofs in New Jersey, however, due to the humidity and shade. For instance, if you live in Cape May County, you may find that your roof is especially prone to algae and moss. While the unsightly streaks are a hassle, you can easily deal with them by having a roofing contractor install GAF’s StainGuard Plus technology.
Key Takeaways
- Algae can cause dark roof streaks but usually don’t damage shingles structurally.
- Moist climates increase the risk of algae growth on asphalt shingles.
- GAF’s StainGuard Plus Technology uses copper-infused capsules for long-lasting algae protection.
- The technology is exclusive to GAF and available on Timberline Ultra HD shingles.
- Homeowners receive a 25-year limited warranty with a 10-year non-prorated protection period.
What Causes Stains on a Roof?
If you’ve ever looked at your roof and wondered where the black and blue-green streaks are coming from and how you can prevent them, we’ve got an answer. Black streaks may look like dirt, but they’re actually caused by algae that feeds on the limestone in asphalt shingles. While algae doesn’t cause immediate damage, they do absorb heat and moisture (especially when there’s also moss growth).
When there’s excessive heat and dampness, your shingles deteriorate faster than if they weren’t covered in algae.
About GAF’s StainGuard Plus Technology
According to GAF’s own survey of 500 homeowners, 87% said they found protecting their roof from algae very or extremely important. These products offer the protection that most homeowners want for their roofs. This technology is proprietary to GAF. The company has specially engineered capsules that are infused with copper microsites. Over time, those capsules release algae-fighting copper to prevent them from forming. That means long-lasting protection for your shingles. Along with shingles, GAF’s algae-fighting technology is available on other products, such as ridge caps and starter strips. These products are also covered with a limited warranty.
Is There a Difference Between Roof Algae and Moss?
Yes, there is a difference between the algae that grows on roofs and moss. Moss is a plant that substracts years from the lifespan of your roof if left alone. Algae, on the other hand, while ugly, doesn’t do as much immediate damage as moss.
Furthermore, once algae begins to grow, it can also spread, accelerating shingle aging over large portions of your roof. Keep in mind that asphalt shingles often contain crushed limestone, a food source for the algae. When the roof does dry, and the algae die, there will be dark discolorations on the surface. For that reason, GAF has created StainGuard Plus Technology to help.
Getting Rid of Algae Stains
When you notice those dark spots or black streaks, it is a cause for concern. In most cases, those discolorations develop in the spring or summer. No, it is not dirt. These cyanobacteria have invaded your roof.
While the first thought might be to clean the roof, you must be careful. Adding cleaning solutions and water to clean the algae stains can make a slippery surface. Power washing is often used to remove stains, but it can wash off the protective granules on the shingles. If you want to clean those shingles, you should call a professional company to handle the job. You might be unable to remove all algae stains with a simple cleaning. Once those blue-green algae spores settle on your roof, you could be stuck with them for a very long time.
How Can GAF’s StainGuard Plus Technology Help With Roof Algae?
Unlike the original StainGuard protection, GAF’s StainGuard Plus technology uses specially-engineered capsules that are infused with thousands of copper microsites. Since the particles are spread throughout the capsule, they are released over a longer period. The evenly distributed copper elements provide enough protection to prevent any algae growth. Your shingle granules will continue to release copper even as they get older. You can only find this advanced technology on GAF’s Timberline Ultra HD shingles with the StainGuard Plus stamp.
As previously mentioned, this technology is exclusive to GAF. If you want the best protection for your roof against the dreaded blue-green algae, you need to purchase GAF products. Along with that, you can ensure complete protection of your roof when you work with a Master Elite roofer who is certified to install and maintain products from the GAF line.
With all GAF products, you are guaranteed long-lasting quality. The StainGuard Plus technology found in this shingle will come with a 25-year limited warranty that protects against algae discoloration. The warranty features a non-prorated period of 10 years. In basic terms, you will not have to worry about dark stains on your roof for a very long time. If your StainGuard Plus shingles do happen to exhibit any blue-green discoloration in those first 10 years, GAF will fix the problem for you. The company will cover the cleaning costs or install new asphalt shingles on the roof.
Blue-Green Algae & StainGuard Plus FAQ
Q: Are blue-green algae harmful to my roof?
Not structurally. They mainly cause black or brown streaks that make shingles look dirty and aged.
Q: How is algae different from moss?
Moss is a plant that can damage shingles, while algae are microscopic bacteria that leave behind stains without eating into the roof.
Q: Can I clean algae stains myself?
It’s not recommended. Power washing or harsh cleaning can strip protective granules from shingles. Call a roofing professional for safe cleaning.
Q: How does StainGuard Plus protect against algae?
It uses engineered capsules with thousands of copper microsites that release algae-fighting copper over time, preventing stains from forming.
Q: What warranty comes with StainGuard Plus shingles?
They include a 25-year limited warranty, with the first 10 years covered under a non-prorated algae protection guarantee.
Stay Protected with StainGuard Plus Installed by RGB Construction
If you’re worried about those dark streaks on your roof, there’s a simple solution: GAF’s StainGuard Plus. Once installed, your roof will be protected from algae stains and accelerated aging for many years. When you need a Master Elite roofer for your home, turn to RGB Construction. We have extensive knowledge about all GAF products, including those with StainGuard Plus technology. Our team will work hard to install those new shingles and keep them maintained.
Protect Your Roof with GAF StainGuard Plus
Say goodbye to ugly roof streaks with GAF’s algae-fighting technology.
Work with RGB Construction, a Master Elite roofer, to install shingles backed by StainGuard Plus protection.
Call us today at 856-264-9093
or schedule your free consultation online.







