Vapour membranes – what are they & how do they affect a space?
A vapour barrier or vapour membrane, also known as a vapour retarder, is a material used in construction to prevent moisture from passing through the building envelope, including ceilings, walls, and floors. The purpose of a vapour membrane in a ceiling is to reduce the transfer of water vapour, or moisture, from the indoor space to the insulation and structural components of the ceiling, and to prevent condensation from occurring within the building assembly.