Most aluminium composite cladding consists of a layer of plastic sandwiched between two aluminium sheetsAnd it's the plastic layer, usually made of polyethene (also called polyethylene), that's

Aluminium composite cladding panels feature a composite core (often made of polyethylene, a highly combustible and flammable construction material) between two thin layers of aluminiumThis composite cladding option offers a cheap alternative, however recent disasters such as the Grenfell Tower fire in London in means this type of product