Foil Backed Plasterboard slabs have similar properties to ordinary Plasterboard Slabs except they have a foil layer which acts as a vapour barrier to limit moisture diffusion. This foil backing provides excellent vapour resistance, making it ideal for use in roofs, decks, and walls. They are ready for either direct decoration, providing the correct jointing and sealing procedures have been followed, or 'skimmed' with a suitable plaster finish. Foil Backed Plasterboard offers a basic level of fire, structural, and acoustic performance. It is available in a size of 8ft x 4ft.