Ökologisch optimale Dämmdicken bei Wohngebäuden

Ecologically optimal insulation thicknesses for residential buildings.

The Swiss building stock consists of 83 % residential buildings. Residential buildings cause 46 % of the total energy demand and 19 % of the total environmental impact in Switzerland. The question then arises as to which insulation thicknesses and what types of heating systems are optimal? In a survey the optimal insulation thicknesses for residential buildings in Switzerland were calculated. In order to take the influence of the focus on different environmental aspects into account, primary energy, global warming potential and environmental impact points were used as optimization criteria. A mathematical model for the analytical calculation of the optimum was developed. The influence of different parameters (e. g. the influence of the insulation material or the location or the energy carrier) was shown. The developed calculation method allows a quantitative analysis of ecological insulation standards. The three environmental indicators lead to different optimal insulation thicknesses. In many cases, particularly the first part of the thermal insulation - approximately 20 cm (equals U ≍ 0.15 W/(m²K)) - is crucial in order to minimize the environmental impact of residential buildings.