Aluminum Composite Panel “ACP” is a building cladding material commonly used in interior and exterior wall systems due to its lightweight, durability, and structural performance. Awareness and concern about ACP cladding and the fire risks associated with ACP cladding have increased recently following a number of cladding fires around the world, including in Australia. ACP cladding system ACP panels are typically 4mm to 6mm thick and consist of a core material sandwiched between two thin layers of aluminum. The thickness of the core material is generally 3mm to 5mm, and the thickness of the aluminum sheet is 0.5mm. Fire Risks Associated with ACP The fire performance of any ACP cladding system installed on a building should be fully understood in terms of its installation, existing fire protection systems, and life safety considerations. The behavior of polyethylene-cored aluminum-clad products is well documented and is classified as flammable. Once ignited, the polyethylene burns violently, with the convective heat propagating the flame upwards involving more cladding panels.
Fires were also shown to spread laterally to cladding panels on both sides by radiant heat and wind-driven convection, which could lead to fires in adjacent surface cladding. A third mechanism of fire spread in polyethylene panels is the burning of the material to produce flaming droplets that ignite the panels below the location of the fire. These droplets can also render the outlets under the PE panel unusable.