You can see those ugly black streaks on roofs almost everywhere. Algae is a problem in most of the country, especially in hot, humid climates, and once it takes hold, it’s hard to get rid of, so prevention is the goal. For decades the industry has offered algae-resistant shingles. Early versions used zinc to prevent algae growth, but copper proved a more effective and longer-lasting solution to the problem.

Copper granules in shingles prevent algae growth, but the amount of copper is crucial; if there isn’t enough copper, even a so-called “algae resistant” roof might fail to prevent algae growth after the better part of a decade. The ugly streaking is an aesthetic nightmare and, if cleaned improperly, it can lead to structural problems as well.

A few years ago, 3M created a splash by offering shingle manufacturers the ability to use the trusted Scotchgard brand if they followed stringent copper granule usage guidelines as part of the Scotchgard Algae Resistant Roofing System. The Scotchgard™ Algae Resistant Roofing System from 3M offered warranties against roof algae for up to 20 years, and PABCO and Malarkey have been offering shingle products with Scotchgard Protection since 2003.

This year, Atlas Roofing Corporation went a step further, becoming the first to offer a Lifetime Limited warranty against algae growth on its StormMaster, Pinnacle, and Pro-Cut shingles with Scotchgard Protector from 3M.

Roofing Contractor spoke with Tim Worms, National Accounts and Marketing Manager, 3M Industrial Mineral Products Division, and Kirk Villar, Vice President, Residential Sales and Marketing, Atlas Roofing Corporation, about the importance of preventing algae growth and the unprecedented warranty now offered by Atlas. They affirmed that their goals for the product include preventing algae growth, giving homeowners peace of mind, and offering contractors a product that can help increase sales and set their company apart from the competition.


The Science and Testing

Wormsexplained the science behind the product. “3M copper granules are combined with 3M classic roofing granules on the exposed portion of the shingle, as well as the hip and ridge, in a 10 percent copper blend and 90 percent classic granule blend,” he said. “This blend is critical as it provides the proper amount of copper protection to earn the Scotchgard brand. Anything less will, in time, lead to algae growth. Period.”

Why does copper work? Worms explained it this way: “3M coats raw mineral with copper. Copper releases ions. We then do a unique color overcoat that is porous enough to allow the copper ions to leach from the granule. Copper ions prevent algae growth when there are enough ions present. These ions are evenly distributed across the roof by gravity and roof moisture and dew. If too little copper ions are present, the algae will overwhelm the inadequate copper, resulting in algae growth after all. That’s why it’s important to have the blend ratio required to earn the Scotchgard brand. Simply having some copper may sound good, but it will fail in time.”

Decades of research and testing have gone into product development, noted Worms. “3M has patents related to preventing algae growth on shingles going back to the 1960s,” he said. “3M introduced the copper roofing granule to the industry in 1991. Prior to this, the industry used zinc granules or zinc strips. Zinc granules worked but they did not last as long as copper. Zinc strips also worked, but they too did not last long and the strips needed to be placed close enough together to accommodate their limited ion reach/spread.”

According to Worms, 3M has test roofs in Texas, Florida, Washington and Oregon — areas with some of the most severe algae problems in the country. “Research on these roofs has been going on for decades,” Worms said.

Ongoing third-party testing ensures manufacturers get it right, said Worms. “Atlas must submit samples from every production run to an independent third-party test lab for verification that the proper copper content is incorporated into every shingle,” Worms said. “If it is not, the shingles are rejected and cannot be sold. If there ever is a claim, 3M and Atlas will work together to ensure the homeowner is 100 percent satisfied with their Atlas roof featuring the Scotchgard Algae Resistant Roofing System.”


The Problem and The Solution

“Homeowners do not like the unsightly stains caused by algae,” said Worms. “It detracts from their single most expensive and important investment, their home. Homeowners purchase one, perhaps two roofs in their life, typically. They trust their contractor to provide the best solutions at the best price. The incremental cost of a roof with Scotchgard Protection is less than the cost of a single roof cleaning. The contractor can confidently offer the roof with the Scotchgard Algae Resistant Roofing System knowing that consumers recognize and trust the Scotchgard brand. The contractor will gain more share at a higher price, resulting in a profitable win for him and the happy, confident homeowner, both of whom have the Scotchgard brand standing behind them.”

The power of the Scotchgard name helps the contractor get his message across to homeowners. “The Scotchgard brand is one of 3M’s crown jewels,” Worms said. “Consumers have come to trust the brand over the nearly 60 years it has been around. Consumer research shows that the brand means long-term protection against staining, it’s a brand name they can trust, the roof will maintain its original appearance and it will prevent algae growth.”

“For homeowners it means they will have the absolute best solution to prevent algae growth and protect the beauty of their investment in their home,” Worms continued. “It increases the value of their home, which is important in these tough housing times. The Scotchgard brand means peace of mind for the homeowner. Not only will the brand provide the contractor with a distinct advantage, but the Atlas limited lifetime warranty is the best in the industry.”


The Product and The Warranty

Atlas began offering the product this summer. According to Atlas Roofing’s Kirk Villar, early reviews have been excellent, said and he’s optimistic the product will be a hit and perform to expectations. Villar agrees that the Scotchgard brand brings along built-in advantages when appealing to homeowners. “It gets people out of ‘commodity thinking.’ It’s a powerful brand,” he said. “3M and the Scotchgard brand are well respected. It puts our shingle in a whole different arena.”

Plus, algae is a real problem, noted Villar. “Black streaking is everywhere — not just in hot, humid areas,” he said. “Basically it’s a problem everywhere east of the Rockies and all along the West Coast.”

Roofs are increasingly important factors when it comes to curb appeal, noted Villar. “With steep pitches, the roof accounts for 60 percent of the home in view. Roofing is key to the appearance of the home. And the curb appeal of the home is pretty important these days — especially when you go to sell it.”

You can clean an algae-streaked roof, but it’s expensive and it’s not a lifetime fix, noted Villar. “Why not do it right he first time?” he asked. “Why have someone up on your roof five or six years after it’s installed to take care of algae? Invest in that on the front end.”

In the past, some Algae-resistant shingles in the past didn’t do the job for very long, noted Villar. Some used only a minimal amount of copper, which soon leached out, and some only had copper in the dragon teeth. “Copper granules don’t kill the algae — they keep it from starting,” he said. “If the copper is only on the dragon teeth, the algae can start in other spots and spread over the roof. Once it starts, it’s like poison ivy or chicken pox — it just spreads. You’ve got to cover the whole shingle to be effective.”

He has confidence in the lifetime warranty. “The key is it’s third-party tested by 3M before it is qualified to be sold,” he said. “We have to send multiple samples per day, per plant, to confirm we put the proper amount of copper in. Third-party quality control ensures we meet our specs, or production is rejected. The Scotchgard brand is a crown jewel of 3M, and the last thing they want is a product that doesn’t work all of the time.”

Villar believes offering this product can help contractors differentiate themselves. “It totally separates him from the run-of-the-mill contractor,” he said. “It also addresses a very important part of the roof — aesthetics.”

“If I’m a contractor, I want to be able to offer the homeowner exactly what they want: peace of mind, something that’s hassle free, the Scotchgard brand, and excellent aesthetics. And protecting that investment is value added. I want to protect the look, protect the beauty, protect the color, and make my life simple. This product does that.”

Helping contractors is what it’s all about at Atlas, said Villar. “The roofing contractor is our customer. This is all designed to help the contractor get the job. The perceived value of the roof goes up when they mention the Scotchgard and the 3M brands. It’s a well-known brand that homeowners can identify with. Some homeowners might not recognize the names of roofers or roof manufacturers, but I promise you they know the Scotchgard brand and 3M.”

“This product truly has the science behind it,” he concluded. “Our tagline is ‘Atlas has taken Scotchgard Protection to a whole new level — the roof.’”

For more information about 3M, visit For more information about Atlas Roofing Corporation, visit


Contractor and Distributor Feedback

Atlas Roofing Corporation introduced its StormMaster, Pinnacle, and Pro-Cut shingles with Scotchgard Protector from 3M late this summer. It’s too early to tell how these products will perform over the long run, but contractors and distributors who spoke with Roofing Contractor were optimistic about its future.

Jim Owen, Vice President, Sales and Marketing for JGA Beacon, works in Atlanta, where algae growth is a substantial problem. He said, “One of the things customers ask us is, ‘Is this shingle algae resistant?’ The customer is smarter than they used to be. They go online and do some research, so they’re more up to speed.”

Owen noted product benefits the contractor in several ways. “It at least gives you something to talk about and something to promote,” he said. “It’s hard to make shingles sexy, but it gives you something to talk to the customer about, and hopefully they bring that information to the homeowner.”

It also helps contractors differentiate themselves. “The Atlas algae-resistant product with Scotchgard Protection is new,” said Owen. “If contractors are savvy and learn how to sell well, it gives them a leg up on the competition.”

Brad Jones, owner of Rooftime Contractors, thinks offering the product gives him an edge. His business is headquartered in Midlothian, Texas, with offices in Dallas/Fort Worth, Houston, Austin and Oklahoma City. “We have a lot of staining that goes on in the Houston and Austin markets,” he said. “For the people with stains on their roofs, it’s a huge factor. Being able to offer the lifetime warranty is a huge benefit to the customer. 3M and Scotchgard Protection have been well marketed to homeowners. Name recognition is off the charts with 3M and the Scotchgard brand, and their reputation is off the charts.”

“Appearance is perception,” he said. “If I’m putting on roofs I’m using as references, and people go by a house that’s close to them and they have staining on the roof, it’s not going to look good. I want to know it will look good in 15 or 20 years.”

He noted the product helps him close more sales, and the cost for the upgrade is nominal — on an average job it’s about $45. “I think this product will revolutionize the market like architectural laminate shingles did,” he concluded. “It will become the norm over the next two to three years.”