Most fire-rated walls are an assembly of materials hoping to act as a system. The ESP panel inverts that: it is a system designed first, then resolved into the five layers required to make it true.
The galvanized steel skin handles ember impact. The ceramic intumescent coat activates at 482°F and expands forty times its volume to choke off oxygen at the surface. The mineral wool core holds dimension to 2,150°F. The cementitious board carries load. The service cavity removes every penetration through the fire envelope.
Together, the five layers buy a four-hour rating without resorting to cement-board cladding or sacrificial finishes. The wall does the work.
