When it comes to getting climate change under control, the building sector is also called upon. During BAU ONLINE, our author Thomas Geuder followed a panel discussion with politicians, scientists, and researchers.
Climate change is omnipresent—in Germany as well. Considering that buildings are responsible for up to 30 % of national greenhouse gas emissions, the building sector can make an important contribution to climate protection. However, planning and building must be also adapted to the climate, because the consequences of climate change are already having a direct impact on existing buildings—and thus on society.
The major goal of achieving a nearly climate-neutral building stock by 2050 is currently one of the most important drivers in the building sector. The consequences of climate change can be reduced noticeably here. And the pressure to act is high: 2020 was the warmest year on record. Weather extremes such as heat, heavy rain, floods, and storms have increased significantly. The risk has been recognized. Now, it is about finding out how future buildings have to be designed to counter climate change and its consequences. Continuing to build as before cannot be the answer.
In addition to climate protection, one of the most important steps for the future is to adapt building to the climate. And what is even more: in line with sustainable construction, overarching climate strategies must be found. The “German Strategy for Adaptation to Climate Change” (DAS) has been dealing with this task since 2008. The Federal Environment Agency's initiative identifies risks because of climate change as well as possible targets and measures. One central approach is joint, interdisciplinary action. The maxim of DAS follows the development of an urban, blue/green infrastructure that can ensure the quality of life in cities while protecting the climate and mitigating the consequences of climate change.
Many ideas for structural adaptation—and consequently for climate protection—are already on the table. Examples: to compensate for increasing land sealing, buildings can be greened (roof, facades). This avoids an increase in ambient heat as well as a reduction in evaporative cooling. Blue/green roofs and streets can help deal with rainwater properly as the rainwater is not only drained but stored directly on site for later use. Much can also be done in dealing with gray energy or in designing the shape of buildings and the geometry of entire settlements.
Hans-Joachim Schellnhuber explains that it is essential to restore the balance in the forest/mineralization/photosynthesis/humification system. He proposes to reforest forests and, at the same time, recycle buildings as part of the “wood/building pump.” This simple system allows fossil fuels to be transferred back into built forests, thus repairing the anthropogenically disturbed system, i. e. disturbed by burning fossil fuels and cutting wood.