The buildings sector (construction, operation, maintenance and renovation) accounts for more than half the emissions of CO2 in Switzerland. For new buildings, the necessary technologies for optimisation in terms of CO2 emissions are largely available today, but in practice they are still being insufficiently implemented. Further development is required in the areas of design, construction processes and materials. The medium-term objectives of the Swiss Federal Energy Research Commission (CORE) include the reduction of energy consumption in buildings by fifty percent and the elimination of the consumption of fossil fuels in heating systems in buildings. The Swiss Federal Office of Energy (SFOE) created the Energy in Buildings research programme in order to identify ways in which these demands can be met.