Visqueen Fully Bonded (FB) Vapour Barrier is used to omit the risk of interstitial condensation within a structure as well as improving the general airtightness of the building. Visqueen FB Vapour Barrier restricts the passage of warm, moist air from within the building from permeating into the structure or the roof. It is commonly used within timber frame housing as well as commercial buildings. Visqueen FB Vapour Barrier is a tough multi layer reinforced HDPE membrane with an aluminium foil.