The secretive, toxic materials behind the green building revolution


With thousands of green building professionals and manufacturers set to gather in Washington, D.C. this week for the annual GreenBuild conference, Kingspan insulation manufacturing workers expose the dark side of a “green” building industry.

Kingspan Group is a $15 billion public firm claiming to be the world’s leading producer of “green” high-performance insulated panels and building envelope products. It is scheduled to have four booths at the GreenBuild expo this week. Many in the United States are not aware that between 2006 and 2020 its U.K. insulation business had a 14-year record of making misleading fire safety claims, revealed in 2021 through the U.K. government’s public inquiry into the Grenfell Tower fire. Kingspan claims it is reformed, but workers at its Modesto, Calif., factory have filed a complaint. with the California Occupational Health and Safety Administration (Cal-OSHA). Their allegations not only call Kingspan’s compliance reforms into question, but raise important questions as to what it means for a company to be “green” when its workers face daily occupational health hazards.

Greenwashing and inadequate oversight related to:

  • Dangerous and “Proprietary” Chemicals: Kingspan’s star product QuadCore is a “hybrid polyisocyanurate” (PIR) foam core, made primarily of Isocyanate (MDI) and approximately 39% secret “proprietary” chemicals. Kingspan’s marketing materials include broad claims about the safety of the materials in use, including a statement that the level of MDI in the product does not warrant the need for product warnings. But that statement makes no mention of workplace exposure risks. MDI is a family of chemicals that the EPA states are “known dermal and inhalation sensitizers in the workplace and have been documented to cause asthma, lung damage, and in severe cases, fatal reactions.” At least one worker is experiencing chronic symptoms associated with MDI exposure: cough, headaches, and throat and nasal irritation.
  • Third Party Certifications: In the transition to energy efficient buildings, petroleum-based insulation products dominate the market. There is growing market pressure to reduce the embodied carbon of products. Environmental Product Declarations (EPD) provide one way for manufacturers to demonstrate they are doing so, but the data is typically self-reported to small private certifiers. Reports from workers in Modesto reveal that a QuadCore EPD secured in 2022 omits key, waste-intensive and labor-intensive operations performed by about half the Modesto workforce. Kingspan touts another certification from the company Cradle to Cradle, which ranks QuadCore as “Silver” for Material Health but goes on to reveal that all the ingredients are considered either “highly problematic; targeted for phase-out,” “moderately problematic, but acceptable for use” or “unassessed.” None of the ingredients are described as “optimal.”   
  • Working Conditions: The Cal-OSHA complaint alleges chronic exposure to dangerous insulation dust, MDI and other toxic chemicals, inadequate ventilation, a history of inadequate training for hazmat and lack of personal protective equipment. Workers report high levels of plastic foam PM10 dust (particulate matter 10 micrometers or less in diameter). The California Air Resource Board – a state agency – has identified short-term exposures to PM10 as associated with worsening of respiratory diseases leading to hospitalization and ER visits. Says one worker, “There’s dust flying everywhere. There’s machines that are supposed to catch it but… the filters are so, so dirty… They blow with the air hoses to clean under the machines, and people will start coughing and stuff… You can feel it right away, the itchiness, the coughing. And you go on break, you blow your nose and you can see it all in there.”
  • Fire safety: Petroleum-based insulation products are combustible and must meet certain standards for fire safety. To show a product meets the local fire testing requirements, manufacturers pay private testing companies to conduct relevant tests. The full results are kept secret, including any prior failed tests or changes to formulas. No federal regulator of building products exists to investigate issues like those exposed through the Grenfell Inquiry in the United Kingdom. Although Kingspan emphasizes that its product Kooltherm K15 was only 5% of the insulation used to refurbish the Grenfell Tower and was used without the company’s knowledge, the inquiry revealed that Kingspan kept failed tests secret from certifiers and was marketing K15 in the United Kingdom for systems for which it had not been tested and was not compliant.