Recycled Content Use Shows Commitment to Sustainability

The fiberglass and mineral wool insulation industry’s commitment to sustainability continues to grow. The latest recycling data from NAIMA’s annual survey of its members’ use of recycled content highlights just how significant that impact has become.

In 2025 alone, NAIMA member companies in the United States and Canada used more than 2.9 billion pounds of recycled materials to manufacture thermal and acoustical insulation products for residential, commercial, industrial, and HVAC applications. For builders, insulation contractors, and energy-efficiency professionals, the numbers reinforce an important reality: insulation products are not only critical for reducing energy use in buildings, but they are also increasingly manufactured with sustainability in mind.

The survey revealed that U.S. manufacturing facilities used more than 2.4 billion pounds of recycled glass last year, while Canadian facilities used more than 398 million pounds. Combined, manufacturers also reported using more than 567 million pounds of recycled slag in insulation production.

Why It Matters

Using recycled materials provides a dual environmental benefit. It reduces the need for virgin raw materials while also diverting large amounts of waste from landfills. Materials such as recycled glass containers and slag that might otherwise enter the waste stream are instead repurposed into high-performing insulation products that help improve building efficiency and occupant comfort.

For building industry professionals, this matters because demand for low-embodied-carbon construction materials continues to rise in both residential and commercial markets. Builders and contractors are increasingly being asked by homeowners, developers, and code officials to demonstrate how projects support sustainability goals and energy performance targets. Insulation products manufactured with high levels of recycled content can help support those conversations.

The industry’s long-term progress is especially notable. Since NAIMA’s recycling program began in 1992, member manufacturing facilities have diverted more than 13.6 billion pounds of recycled materials from the waste stream.

“This industry continues to demonstrate its commitment to manufacturing products with low embodied carbon that deliver energy savings over the life of the building,” said Curt Rich, president and CEO of NAIMA. “One of the goals of our Sustainability Committee is to work to expand glass collection so that we can produce insulation with a high percentage of recycled glass content.”

Driving Sustainability for the Long-Term

As building performance standards continue to evolve and energy efficiency remains a top priority, insulation will continue to play a central role in reducing operational energy use while helping the construction industry move toward more sustainable material choices.