Skip to main content
Home » Disaster Prep and First Response » How Innovative Roofing Solutions Can Reduce Smog and Cool Communities

For years, 3M has produced durable and colorful roofing granules that are used to make asphalt shingles. They recently innovated two roofing products that are just as durable and colorful that could make a significant impact on both cooling communities and fighting smog.

“There are cool roofing solutions — things that can help with urban heat island mitigation — and then smog-reducing granules that can help be part of the solutions for air pollution,” says Maureen Tholen, a sustainability director for the company.

These roofing innovations are a game changer.

“The guys who brought you Post-Its are thinking about your health also,” says Jonathan Parfrey, founder and executive director of Climate Resolve, a climate advocacy and environmental organization.

“With the roofing materials they’ve been innovating, you can be more comfortable in your home, safer in your home and doing your part for the environment.”

Cool down

The Environmental Protection Agency defines a “heat island” as a built-up area that’s hotter than nearby rural areas, noting a city with a million or more people can annually be 1.8–5.4°F warmer than surrounding areas. Temperatures are often over 20°F warmer in these areas at night than during the day. Heat island impacts can include higher summertime peak energy demand, increased air pollution and more greenhouse gas emissions.

The City of Los Angeles has been aggressive in targeting the problem. Their “Cool Roof” ordinance, which was implemented a few years ago, requires new roof installations and remodels to be solar reflective and thermal emitting.

The patented 3M™ Cool Roofing Granules reflect more sunlight, absorb less heat than a typical roof and can help consumers save on cooling costs year-round.

“You’re going to start making an impact,” says Tholen, noting the cumulative effect of cool roofs can really add up.

“Everybody can do a little bit,” says Gregory B. Malarkey, senior vice president of Malarkey Roofing Products®, a company that turns the 3M granules into asphalt shingles.

The cooling granules can also prolong the life of the product.

“The number one thing that speeds the aging of the asphalt is elevated temperatures,” he says. “If we can reduce the aging rate of the asphalt and protect it from the sun, we can create a shingle that will last longer and perform better.”

Smog fighter

Forty-one percent of Americans live in counties with unhealthy levels of ozone or particle pollution. That’s according to the American Lung Association’s “State of the Air 2018” report, which ranks Los Angeles as the No. 1 city with the worst ozone pollution. That’s one of the cities where 3M™ Smog-Reducing Granules hope to make a big impact. While they look like typical shingles, there’s one major difference: the embedded technology can actively reduce smog.

“It’s sunlight driven,” says Tholen. “The coating on the granule will be activated by UV sunlight and can take smog that has landed on the roof and turn it into a water-soluble ion.”

3M sent the granules and shingles to Lawrence Berkeley National Laboratory for evaluation. The testing validated the photocatalytic materials used can reduce smog and contribute to cleaner air.


“People are really concerned about their health,” says Parfrey. “This is a way — just by choosing the right kind of roof — you can do things to protect your health. We think that’s a great win-win.”

Both types of shingles made from cool and smog-reducing granules are affordable and cost effective to implement.

Malarkey says the shingles are even more beneficial. “In 2018 we anticipate producing enough shingles to have the smog-fighting capacity of over 100,000 trees,” he says.

Next article