This Standard sets out requirements for the installation of pliable building membranes (also known as ‘sarking’ or ‘underlay’), when used either independently or as a facing to other materials, such as insulation materials, for any one or more of the following control functions:(a) Water control.(b) Thermal control.(c) Vapour control.(d) Air control.This Standard does not cover requirements for materials used in the following applications:(i) Air-handling ducts and building services.(ii) Under concrete slabs on-ground.(iii) Waterproofing above flat concrete roofs.NOTES: 1 The installation of foil-faced building blanket is covered in AS 3999, except for metal sheet roofing and walls, which are covered in Section 3 of this Standard.2 Where regulations require special attention in bushfire prone areas, it may be necessary for a pliable building membrane to comply with AS 3959.3 This Standard includes advice on work health and safety (WHS), and electrical safety (see Appendix A); however, the user of this Standard needs to refer to relevant federal, state and territory regulations and determine legal requirements as applicable.