Vienna Patent Office / Vienna Green Hub

In line with circular economy principles, demolition was avoided, and the existing reinforced concrete structure was preserved. Reusing the skeletal framework alone saved approximately 50 percent of embodied carbon emissions compared to a new building. Furthermore, CO2-reduced recycled concretes (ECOPact with ECOCycle technology) were used exclusively for all new components. The new building envelope was designed as a timber facade with integrated photovoltaic modules, combining energy efficiency with a resource-conserving selection of materials.

The energy concept is entirely renewable: 19 geothermal probes and a heat pump utilize the ground for thermal control, while the extensive solar array generates more energy than the building consumes during operation. A central atrium with a continuous staircase forms the architectural heart of the building and promotes natural lighting. Through this combination of structural preservation and innovative building services, the project now serves as an active carbon sink and a best-practice example for the sustainable transformation of post-war modern architecture.