Unlike many other places, which may use materials like slate and terracotta for roofs, North America predominantly covers houses with asphalt shingles. About 75% of U.S. roofs are covered by this material, due to its low cost, water-repelling qualities, and ease of installation. But, the abundance of the material puts strain on the environment. According to the Environmental Protection Agency (EPA), 11 million tons of asphalt waste is generated every year, most of which ends up in landfills. It takes about 300 years to decompose.

Solving the environmental toll has been a priority for GAF, the biggest roof manufacturer in North America. More than 12 billion square feet of shingles are manufactured each year, and they last about 12 to 15 years on the typical roof before they need to be replaced. “What do we do with those shingles when we take them off?” asks Jim Schnepper, the company’s president. After four years of development, GAF, an operating company of Standard Industries, has announced an industry first: a new patented process whereby otherwise wasted asphalt is recycled and converted into new shingles for roofs—creating a circular roofing system that the company aims to streamline into its entire product line.

Recycling asphalt is not a new technique; roof shingles are sometimes recycled into paving shingles, but it’s proved easier for the paving industry to create a circular system, recycling old road asphalt for new road asphalt. For the roofing industry, trials so far have struggled to find the balance between cost and performance, says Dan Boss, GAF’s senior VP of research and development. It’s expensive to extract the pure asphalt out of the shingles; on the other hand, keeping the other materials in the shingle—namely the rock granules—can degrade the quality of the new product. Boss says GAF has now perfected an affordable way of recycling the shingles, while cleanly removing that “stone dust,” whereby 90% of the shingle waste material is reused.

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