Profile: Metra Non-Ferrous Metals Ltd. supplies hard metals for the roofing and cladding industry. Our rainwater system is a method of removing water easily from buildings. It is used on both domestic & industrial buildings. It is made from naturally occurring metals, zinc and copper. It is available in various finishes and they can readily suit the requirements of the architect or building owner. Metboard is a rigid insulation panel with an adhesive on one side which is simply adhered to any non-ferrous metal.