The buildings sector accounts for about 40% of final energy consumption in Germany, and by far the largest part of this is due to old buildings. In total, more than 80% of the final energy consumed in households is used for space heating and hot water (Federal Statistical Office 2010)....

Climate change will affect the frequency, intensity and regional occurrence of extreme weather events and lead to gradual climatic changes. Although climate change impacts appear locally at first, they spread beyond political borders due to the global physical and economic interconnectedness....