The decision to convert the Althan Quartier in Vienna‘s 9th district instead of building it new will have a major impact on the CO² footprint of the project: all in all, the reduction amounts to 18,625 t CO², which corresponds to 67 %.

Althan Quartier
Existing building before conversion
Architect Karl Schwanzer

Study and analysis of the existing building

The new design was preceded by an extensive reading and understanding of the existing building from the 1970s. Using historical plans and documents, DMAA and JWA analysed and internalised the initial ideas of the original architect Karl Schwanzer in order to make a fundamental decision between demolition and conversion. With the help of BIM (Building Information Modelling), a digital twin of the existing building was created, which enabled comprehensive studies of the concrete cubature and the consequences of possible adaptations. The potential of the existing building with its economically optimised reinforced concrete structure, which was exceptional for the 1970s, was thoroughly examined 
in terms of statics, noise and fire protection as well as suitability in terms of building physics.

Characteristics of the existing building in its function as the headquarters of Bank Austria were the mirrored façade and a striking, expansive but almost unused staircase. The mirrored façade emphasised the hermetic nature of the building, while the monumental gesture of the external staircase dominated the area of Julius-Tandler-Platz. The remodelling allowed these outdated stylistic elements to be removed.

Development of the new

One of the main focuses of the planning process was to create a new opening to the neighbourhood: new urban places to linger, semi-public spaces, barrier-free access and restaurants with open spaces were to be created. The dimensions and substance of the office building were retained, but new open spaces were created, making Julius-Tandler-Platz much more attractive with a new look and increased accessibility.
Situated nine metres above street level and above the tracks of the railway tunnel, the new plaza level in the inner courtyard links the valuable open spaces of Spittelauer Platz, Lichtentaler Platz and Julius-Tandler-Platz. 

Decisive premises of the project development were the pedestrian permeability, the opening to Julius-Tandler-Platz, the broadest possible mix of uses, the redensification of an urban core zone and the harmonious integration into the urban space.

Transformation of the Julius-Tandler-Platz

Existing staircase as a barrier 
Expansion of the square by removing the stairs

The façade of the building was freed from its mirroring. The new stainless steel cladding of the façade has a glare-free and silky matt appearance thanks to its fine embossing, while the terraces create additional open spaces for restaurants and offices and a counter-design to the building‘s previous seclusion.
Another planning focus was on the design of a vivid base zone. The extensive opening of the base achieves the desired spatial relationship to Julius-Tandler-Platz, makes the station hall more attractive and creates an inviting connection to the central plaza level. At the northern rear of the building, a connecting structure from the 1970s, between the office complex and the garage, was removed in order to return to Karl Schwanzer‘s original idea of a cubic solitary building.

The redensification was achieved by means of a two-storey extension, which was staggered back in line with the contours of the building and thus blends almost imperceptibly into the physiognomy of the existing structure.

The eight office storeys with their spacious outdoor areas offer around 40,000 m² of usable space, looking out over the neighbouring palaces, Liechtenstein Park and across the city centre to St. Stephen‘s Cathedral. The optimal connection to the local and long-distance transport network, with all major means of public transport accessible within a few minutes, is forward-looking. The connection to the nearby bike routes along the Danube Canal is just as ideal. Secure bicycle parking spaces are available on the first floor of Francis. The intelligence of the building is also evident in the supply and disposal system: this is organised via the underground loading yard, thus keeping above-ground delivery traffic to a minimum.

The conversion project benefits from the intelligent economy of the existing building‘s skeleton structure. Column spacing of 10 metres and the removable prefabricated ceiling allow the greatest possible flexibility for the design of the conversion. Attractive room heights of up to 3.5 metres, which are rarely realized in new buildings, provide flair and brightness.

The comprehensive adaptation to today‘s safety standards, safety technology, building physics, statics and earthquake resistance, as well as the achievement of gold certification from the ÖGNI (Austrian Sustainable Building Council/ Österreichische Gesellschaft für Nachhaltige Immobilienwirtschaft) through high ecological standards for building material, underline the importance of this project as a model for future urban transformations. 
The Francis conversion project thus demonstrates the intelligent utilisation of existing building structures and sets new standards in terms of ecological sustainability and urban integration.