The new Part 7 of the Thermal Insulation Standard DIN 4108 describes the permanent design of the airtight layer of heated or air-conditioned buildings. In the chapter on requirements, some terms have been redefined. However, the required values for the maximum air change rate are stipulated in the current EnEV (German Regulation on Energy Conservation). The planning chapter features many new sections concerning the planning task as well as some additional schematic diagrams. The materials chapter deals with the suitability and implementation of joints and connections. A dedicated chapter on execution gives many indications on professional working methods and also deals in detail with the issue of subsurface. The last chapter now contains new and additional examples and diagrams. The presentation will also cover the use and state of development of a standard for adhesives for airtight layers.