To fulfill the climate target that EU and the Swedish government have decided to apply, it becomes increasingly important that the energy efficiency of existing buildings and making new buildings energy efficient as possible. Of Sweden?s total energy consumption in 2011 was 40% used by residential and service. Of the 40% of the energy consumption was 60% used for heating and domestic hot water. A report from year 2012 shows that one reason why the heating volume is so great could be due to underestimating on the energy consumption for the heating in the planning of the building.