Here at CCF we stock Vapour Control & Breather Membrane Systems to ensure breathability and vapour permeability for any project specification. As part of our wide range of Vapour control and Breather Membranes we also stock a range of Vapour Control Layers and Building Papers. A vapour control layer, is usually positioned on the inner side of insulation, It’s primary purpose is to prevent any water from passing through the layer. A breather membrane is positioned on the outer side of the insulation, which allows vapour to escape from the inside while reducing any water entering. Building papers are more commonly used to stop wind from entering into a wall and to also act as a secondary moisture barrier behind cladding.