The contribution of the German building sector to achieve the 1.5 °C target

Abstract The melting greenhouse gas emissions budget of the German building sector for the 1.5 °C target requires fast counteraction. In this paper, an analysis of the applicable legal and regulatory framework, the funding situation as well as national and international strategies on a transformation towards climate neutrality elucidates that the suggested approaches do not take a holistic view into account. They neglect, that embodied emissions from construction and emissions from operations phases of buildings must be oriented on the remaining budget, as well as material and human resources associated with the required actions. Therefore a framework to decarbonise the German building sector with eleven recommendations for action, which addresses these findings, is developed with a panel of experts. The results clarify, that the focus must be on adapting the existing building stock since renovation processes release significantly fewer emissions than the construction of new buildings. Stricter legal requirements for building envelopes have no significant effect on the reduction of emissions. Instead, fast-acting measures, such as the usage of district heating, photovoltaics, heat pumps, the optimisation of building operation and digitalisation, must be implemented in a prioritised manner to save resources and maintain the emissions budget longer. To be able to align effective measures it is necessary to engage all Stakeholders and to establish reliable political guidance down to the building level. HIGHLIGHTS A decarbonisation framework for German building sector is developed. An emissions budget is required as a benchmark for measures in new buildings and stock. Focus on fast-acting measures in existing buildings to maintain the budget and resources. Establish a buildings database to evaluate the state, plan resources and monitor effects. The energy sector has to decarbonise simultaneously, due to increasing interconnection.