Composite panels are mainly used for internal hoardings and comprise of a ‘U’ section powder coated base/wall channel which accepts a pre determined thickness of panel. The panels themselves are made of powder coated thin steel either side of an expanded polythene core. They have good noise and fire properties and can also be installed very quickly by experienced installers. The downside is that the panels are expensive and once cut, cannot be modified for re-use. They are also difficult to recycle due to their composite nature.