High levels of energy efficiency are all the more important when it comes to high-rise buildings. For the first time ever, a high-rise office tower, located in Vienna, Austria, has achieved the Passive House standard.

The Passive House concept represents today’s highest energy standard with the promise of dramaticaly slashing heating energy consumption. A Passive House is a very well-insulated, virtually air-tight building that is primarily heated by passive solar gain and by internal gains from people, electrical equipment, etc. Energy losses are minimized.

The glazed facade of the RHW.2 building on the bank of the Danube Canal rises almost 80 meters (263 feet) high. The building, characterized by superior indoor air quality and minimal energy consumption, is home to 900 employees of the Austrian Raiffeisen-Holding Group. “This building proves once again that the Passive House Standard and good architecture are perfectly compatible”, says Professor Dr.Wolfgang Feist, director of the Passive House Institue.

“The building is strictly in line with the Raiffeisen climate protection objectives,” explained Wolfgang Pundy, project manager of the RHW.2 tower. “This certification proves that the path we have chosen to take for our new office building is the right one.”

The building’s energy concept is compelling: energy is provided by a photovoltaic system as well as a combined heat, cooling and power plant. Even the waste heat from the data centre is re-used; cooling partly takes place via the Donaukanal.

The decisive factor for achieving the Passive House standard was the radically increased efficiency of the facade, the building component connections, the mechanical systems – and even the coffee machine. In combination with optimized shading equipment, the heating and cooling demand was reduced by 80% compared with conventional high-rise buildings.

The Vienna Region is setting the pace, not only with its beacon projects but also with the number of completed buildings. The “Eurogate” district, an area entirely consisting of Passive House buildings, stands as a shining example. Upon completion of the first construction phase, 7,000 occupants in 800 apartments will be able to benefit from the advantages of this energy efficient construction method.

Over the last 10 years more than 15,000 buildings in Europe - from single and multifamily residences, to schools, factories and office buildings - have been designed and built to the Passive House standard.

Image courtesy of MVAHA