top of page
  • Writer's pictureNeil Burtt

Time-Release Algae Fighting Technology Offers Long-Lasting Roof Algae-Fighting Power

If your home has dark stains on the roof, it may at first glance appear to be a sign of age. However, those spots could actually indicate the presence of blue-green algae growing on your roof, making your roof look older than it is.

How should you help protect your roof against blue green roof algae discoloration? Roofing materials that contain copper can help.

What Is Blue-Green Algae?

Blue-green algae are a kind of cyanobacteria called Gloeocapsa magma. They travel on the wind and thrive in moist environments such as your roof. Because the algae travel so easily, they can quickly spread to whole neighborhoods.

They surround themselves with a brownish-black shell to protect against damage from the sun's rays—which, in turn, is what causes the telltale roof discoloration.

How Does Algae Affect Your Roof?

If you look up toward the roofs in your neighborhood, you'll see that many have dark staining associated with blue-green algae. Although it does not damage your roof, the growth causes dark stains and discoloration that can resemble aging even in newer roofs and may negatively affect the resale value of a home.

How Can You Fight Back against Roof Algae?

For years, copper coated granules were added to roofs to help prevent blue-green algae growth in areas where it is common. When it rains, the metals leach out onto the roof to protect it from algae growth. Less copper is released over time reducing its effectiveness.

GAF Time-Release Algae-Fighting Technology delivers algae-fighting copper in a new way. Specially engineered capsules are infused throughout with thousands of copper microsites, which release copper steadily over time for long-lasting algae fighting power.

What Are the Benefits of GAF Time-Release Algae Fighting Technology?

GAF Time-Release Algae-Fighting Technology is used in many of GAF's most popular products, including shingles, ridge caps, and visible starter strips. The technology is so effective that it allows GAF to offer a 25-year StainGuard Plus Algae Protection Limited Warranty against blue-green algae discoloration on some of its most popular products. Look for the StainGuard Plus™ logo on the following products:

  • Timberline® Shingles

  • Timberline HDZ®

  • Timberline® AS II

  • Timberline® CS

  • Timberline® UHD

  • Designer Shingles

  • Grand Canyon®

  • Grand Sequoia® ArmorShield™

  • Camelot® II

  • Slateline®

  • Woodland®

  • Ridge Cap Shingles

  • Seal-A-Ridge® ArmorShield™

  • TimberCrest™

  • Ridglass®

  • Timbertex®

  • Z® Ridge

  • Starter Strip Shingles

  • StarterMatch™

GAF Time-Release Algae-Fighting Technology provides the algae protection homeowners are looking for. In a recent GAF survey of 500 homeowners, 87% of homeowners thought it was very to extremely important to protect their roof from blue-green algae. 89% said that warranty length was very to extremely important when purchasing algae protection products. GAF Time-Release Algae-Fighting Technology helps meet these homeowner needs.

Help Protect Your Roof for the Long Run

The best way to protect your roof from the effects of blue-green algae is to install products that help prevents it from growing in the first place. GAF shingles with Time-Release Algae-Fighting Technology and the 25-year StainGuard Plus™ Algae Protection Limited Warranty* helps protect against discoloration from blue-green algae.

If your roof needs protection against blue-green algae or you have any questions about the 25-year StainGuard Plus™ Algae Protection Limited Warranty*, contact a local contractor certified by GAF.**

*25-year StainGuard Plus™ Algae Protection Limited Warranty against blue-green algae discoloration is available only on products sold in packages bearing the StainGuard Plus™ logo. See GAF Shingle & Accessory Limited Warranty for complete coverage and restrictions.

**Contractors enrolled in GAF certification programs are not employees or agents of GAF, and GAF does not control or otherwise supervise these independent businesses. Contractors may have agreed that they will use GAF roofing products, and may receive benefits, such as loyalty rewards points and discounts on marketing tools from GAF for participating in the program.

2 views0 comments

Recent Posts

See All


bottom of page