The North American Insulation Manufacturers Association (NAIMA) announced the results of a recent survey of its members' use of pre- and post-consumer recycled materials used in the production of insulation and acoustical products in 2021. The survey includes data from both U.S. and Canadian manufacturing facilities.

According to the survey, U.S. manufacturers used 2.2 billion pounds of recycled glass in the production of residential, commercial, industrial, and air-handling thermal and acoustical insulation. Canadian Manufacturers used more than 411 million pounds of recycled glass.

U.S. and Canadian facilities used more than 729 million pounds of recycled slag in the production of thermal and acoustical insulation. Since the industry's recycling program began in 1992, NAIMA members' plants have diverted an estimated 71.2 billion pounds of recycled materials from the waste stream.

"Our industry continues to demonstrate its commitment to using recycled materials in the production of these essential products," said Curt Rich, president and CEO of NAIMA. "With increased focus on whole building decarbonization, insulation products will be a critical component of that activity. Sourcing recycled materials is one way we can decrease our environmental impact while producing essential insulation materials that ultimately lower building emissions."

While recycled content is just one indicator of a product's environmental impact, the survey results illustrate the industry's significant impact through the continuous use of materials.

For more information about the environmental benefits of fiber glass, rock wool, and slag wool insulation, visit