In the last few years, economic and ecological objectives led to ever more stringent requirements in terms of energy efficiency in building construction. The installation of additional insulation materials on the load-bearing structure is the currently most frequently used method in order to comply with these requirements. The resulting economic savings for heating and cooling during use of the building are described as sustainable. If considering the life cycle, the production and disposal of plastic insulation materials, however, is less sustainable from an economic and ecological point of view. Such insulation materials affixed to the wall require intensive maintenance and are difficult to separate in case of demolition or refurbishment and need to be disposed in a special way.
The use of infra-lightweight concrete (ILC) is a very promising alternative. For 15 years now, the civil engineers at the Chair of Conceptual and Structural Design at TU Berlin have been researching in that field. Infra-lightweight concrete is a load-bearing thermal insulation, allowing for simple construction with added architectural value simultaneously. This approach starts with the realization that thermal insulation, as long as we are dependent on it, must be durable and recyclable. Most notably, construction will be easy again. Hence, it is possible to eliminate a lot of currently necessary, complex, and fault-prone structural solutions for the connection of windows and façades as well as the thermal separation between exterior and interior components. Infra-lightweight concrete leads to comprehensive freedom of design and allows using concrete again in a material-appropriate way. Several examples taken from practice demonstrate the far-reaching application potential, providing a promising outlook for the construction industry.