On 1 October 2009, new energy-saving regulations (EnEV 2009) came into force in Germany. These lay down different methods of calculation and tighter limits for the dimensioning of the insulation values of building skins. The primary-energy consumption of new or converted structures has to be 30 per cent lower than the values defined in the energy regulations dating from 2007. The minimum U-value required for the outer wall of a new building is now 0.24 W/m2K.