The Metal Construction Association (MCA) has published a new white paper, “Fire Safety of Insulated Metal Wall Panels.”
The document contains detailed information on the efficacy of insulated metal panels (IMPs) for insulation and fire safety requirements in the U.S. and other countries. IMPs are lightweight composite exterior wall and roof panels with two layers of coated thin sheet metal (typically steel or aluminum) wrapped around a rigid foam core to form a stiff composite.
They are tested for fire, structural, thermal transmittance/resistance, foam core properties, water leakage, and air pressure differential. “In some cases, each component of a product can get good fire test results while the entire assembly burns vigorously, and vice versa,” according to a MCA news release. “Therefore, U.S. codes typically require composite assemblies to be fire tested both as a complete assembly and as separate components, particularly foam plastic insulation materials.”
"It's a misconception that non-combustible materials are always preferable to foam plastic materials in exterior claddings,” said Marcelo Hirschler of GBH International, a company specializing in fire test instruments and consulting services, in the release. “IMPs can be used safely in exterior claddings and should continue to be a significant part of building construction.”