Polyurethane (PUR) is one of the most efficient insulation materials on the market. PUR is available in the shape of insulation boards or foam. However, the boards have a better insulation value than the foam variant. PU Foam Polyurethane Insulated Composite Sandwich Panels for Cold Storage Wall and Roof. Steel finishes available in Aluminium, Galvanized Steel, Painted Steel, Stainless Steel.