Roof Stains Don’t Stand A Chance
Against StainGuard Plus™
Introducing StainGuard Plus™ Shingles with exclusive GAF Time-Release technology. There’s no such thing as pretty roof algae. Gloeocapsa magma, also known as blue-green algae, has spread throughout more than 80% of the U.S., leaving dark black stains wherever it grows, and making millions of perfectly good roofs—and the homes they protect—look old before their time.
What is StainGuard™ Plus?
StainGuard™ Plus is GAF’s advanced algae protection technology, introduced in 2018, designed to keep your roof looking clean and streak-free for up to 25 years. Built directly into GAF shingles, this system uses time-released copper technology to help prevent black streaks caused by algae growth. Unlike older roofing materials, StainGuard™ Plus is engineered for long-term durability and performance. It helps maintain curb appeal, extend shingle life, and protect the value of your home.
Learn more about how this technology works directly from GAF’s official StainGuard technology page. Also, if you are considering upgrading your roof, explore our professional roofing services in Dayton and Cincinnati. Choosing the right roofing system today ensures long-term protection, stronger performance, and a cleaner, more attractive home exterior for years ahead.
That’s why we’re proud to introduce StainGuard Plus™ Time-Release technology. It’s algae resistance so powerful, it comes with a 25-year ltd. warranty against blue-green algae discoloration.*
What Causes Roof Algae?
Those dark streaks on roofs are not dirt—they are caused by a type of blue-green algae known as Gloeocapsa magma. This airborne algae spreads through spores carried by wind, animals, and moisture, making it a widespread issue across residential neighborhoods.
Algae thrives in environments with high humidity, shade, and consistent moisture. Once it lands on your roof, it feeds on the limestone filler commonly found in asphalt shingles, leading to visible staining. According to GAF, algae growth is one of the most common causes of roof discoloration nationwide. Homeowners in Ohio are especially vulnerable due to seasonal humidity and shaded roofing conditions. If you’re noticing streaks, it may be time to schedule a roof inspection.
Say Goodbye to Ugly Black Streaks
Many traditional algae-resistant shingles use a granule technology developed more than a quarter century ago. The granules contain a layer of algae-fighting copper that is released onto the roof when it’s wet. But as the roof ages, those older granules release less and less copper, reducing the shingle’s algae resistance.
StainGuard Plus™ Time-Release technology from GAF releases algae-fighting copper more efficiently, over time, for long-lasting algae-fighting power.
Unlike the older layered technology, StainGuard Plus™ technology uses specially engineered capsules* that are infused throughout with thousands of copper microsites so copper remains within reach, ready to be activated in the battle against blue-green algae stains.
Why Roof Algae is a Serious Problem
Roof algae is more than just an eyesore—it can impact your home’s appearance, efficiency, and long-term durability.
• First, algae significantly reduces curb appeal. Black streaks can make even a newer roof look aged and neglected, which can lower perceived home value.
• Second, algae may increase heat absorption. Dark streaks can cause your roof to retain more heat, potentially increasing cooling costs during warmer months.
• Third, long-term exposure can contribute to premature wear. While algae itself may not immediately damage shingles, prolonged growth can weaken the roofing system over time.
That’s why solutions like StainGuard™ Plus are critical for homeowners who want long-lasting protection. You can also explore our full range of shingle roofing systems to find the right fit for your home.
Stop Roof Algae Before It Spreads — Schedule Your Free Quote Today
*StainGuard Plus™ Time-Release technology and 25-year ltd. warranty against blue-green algae discoloration available only on Timberline Ultra HD® shingles sold in packages bearing the StainGuard Plus™ logo. Does not apply to Timberline Ultra HD® Reflector Series™ Shingles. See GAF Shingle & Accessory Ltd. Warranty for complete coverage and restrictions.
