Coil coating

A thick, usually embossed coating based on PVC dispersed in plasticiser, applied by coil coating over primed, galvanised steel used for profiled roofing and cladding sheets. It offers good formability and durability, but cut edges and mechanical damage need maintenance to prevent edge corrosion and peel back.

A coil or spray applied architectural coating based on polyvinylidene fluoride resin, valued for outstanding colour and gloss retention and resistance to ultraviolet light and chemical attack. It is commonly specified for premium metal roofing, cladding and curtain walling.

Corrosion that develops at the exposed cut edges of pre-coated steel roof sheets, typically at overlaps and eaves, where the steel core is not protected by the factory coating system. It appears as coating delamination and rust creeping back from the edge, and is treated by preparation and application of edge protection coatings before it spreads into the sheet.

A dry finishing process in which electrostatically charged powder, commonly polyester, epoxy or hybrid chemistry, is sprayed onto an earthed component and then fused and cured in an oven to form a continuous film. The process is essentially solvent free and allows overspray to be recovered and reused.