BUGGI 50

Ever wonder how a skyscraper could become a beacon of green living? Right here in Freiburg, BUGGI 50 stands as a testament to innovative sustainable architecture. BUGGI 50 isn’t just any building. It’s the world’s first energetically renovated passive high-rise. Originally built in 1968 in the Weingarten district, this 16-story, 45-meter giant underwent a dramatic transformation in 2009 and 2010. Freiburger Stadtbau (FSB), the city’s housing association, spearheaded the 13.44 million euro project. Architect Roland Rombach led the charge, turning what was once slated for demolition into a groundbreaking example of energy efficiency. The renovation of BUGGI 50 was a massive undertaking. The building was gutted and the floor plans redesigned. The original 96 apartments were reconfigured into 139 units. A nearly airtight building shell was created by integrating existing balconies into the living space and adding new ones to the facade. This change sparked some controversy among existing tenants. They found themselves with less living space for the same rent. The building envelope was significantly upgraded. A 20 cm thick thermal insulation composite system was added to the facade. The roof received an even thicker 40 cm layer. The windows were replaced with triple glazing. Aerogel insulation was used above the windows to insulate the roller shutter boxes. A photovoltaic system, capable of generating up to 25 kW, was installed on the flat roof. Ventilation was addressed with a system that extracts used air from the apartments via a heat exchanger and blows in fresh air. A nearby combined heat and power plant supplies the building with hot water via district heating. These efforts drastically reduced BUGGI 50’s heating requirements from an average of 68 kWh per square meter per year to just 15. This resulted in a 57-ton reduction in carbon dioxide emissions. The Fraunhofer Institute for Solar Energy Systems (ISE) meticulously monitored the project. They collected data from 29 apartments across three floors for two years. This allowed them to track the building’s energy consumption post-renovation. The renovation of BUGGI 50 had an interesting social impact as well. Most of the original residents didn’t return after the renovation. The revamped apartments attracted a new wave of tenants, eager to experience passive house living. These new residents received training from an energy consultant upon moving in. FSB also promised them a ten-year rent freeze. A neighborhood management team was in place to support the new community as they settled in. BUGGI 50 stands as a proud achievement, earning recognition for its innovative design. The project was part of a larger urban renewal initiative in Weingarten-West. It won the “Silver” category in a competition for “Energetic Renovation of Large Housing Estates” run by the Federal Ministry of Transport, Building, and Urban Development. The German Council for Sustainable Development hailed the project as a “flagship project.” They praised its contribution to fostering intergenerational living. BUGGI 50 is more than just a building. It is a symbol of Freiburg’s commitment to sustainable urban development and a model for green building practices worldwide.