Summary of contribution: 

• The main goal is to achieve a state where buildings do not negatively affect the climate and its protection. The way to achieve this is a climate-neutral building stock. This needs to start now, especially with buildings with long lifetimes (e.g. public buildings). 
• According to the Paris Agreement, we only have about 10-20 years to achieve climate-neutral buildings. 
• The Passivehaus Institute is working on how to achieve these goals technically, economically and socially. Therefore, they have created a model of all buildings in Germany (their energy needs for heating, hot water and electricity) and based on this they have modelled different scenarios for achieving a neutral building stock. 
• The current legislative constraints (in Germany) are very light and even in 50 years buildings will not meet these criteria. With the use of quality materials (at a level suitable for passive houses) and components in gradual renovations while constructing new buildings in passive standard, about 80% of the energy will be achieved in 50 years. In combination with renewable energy sources, neutrality can thus be achieved by 2050. 
• Continuing to build and renovate buildings at the current quality will not allow the targets to be achieved and is also the most expensive way to go given rising energy prices.