Design director: Andrea Klimko
Year: 2014
Location: Bratislava, Slovakia

As a part of a major revitalization development project under the name Twin City South“, the A1 Tower is expected to become a major landmark in the area. The most essential conditions of the facade design competition set by the developer HB Reavis were retaining the set volume of the object; creating a facade with the highest comfort criteria for office areas, in relation to heat loss, amount of daylight, solar gain and glare control; the aesthetic value, which should reflect the location, positioning and status of the project; and at last the estimated cost of the proposed facade which was not supposed to exceed the limit set by the developer for both the tower and the base block structure.



The industrial history

The plot area belonged in the past to an island created by a branch of the Danube river, used mostly as parks, orchards and hunting grounds for the local aristocracy. With the arrival of the Industrial Revolution in the second half of the 19th century, the area transformed into the industrial district which kept its character until today. Among the most well-known factories built in this part of the city are without a doubt the Apollo refinery and its heating plant, and KABLO, a power cable production factory, both of which were founded in 1895. While the KABLO complex was demolished in 2007-2008 to make space for a new development, parts of the Apollo heating plant were preserved and will become a part of the future structure of the area.




From town blocks to high-rise

The front facade of the proposed office building Twin City – A1 is situated on the intersection of two busy traffic lines: Mlynske Nivy and Karadzicova Street. The typical residential development zone from the 19th and 20th century, its characteristic strict street lines and blocks on the West side of the plot creates a strong contrast with the high-rise office buildings on the North side. While the Twin City complex creates a consistent city block structure with 7-storey buildings on the South-East, the tower represents a connection of the existing high-rise objects with the new development west of the Winter harbor, including the Panorama City and Sky Park projects. In the context of its surroundings, the Twin City complex shows overlapping of the town structure with an industrial look with the new business centre of Bratislava.




More elegant and smooth

Our studio’s proposal made a slight change in the outline of the tower, while retaining the built area specified by the developer and at the same time increasing the overall commercial area by more than 680 square meters. With the addition of several gentle curves, the proposed tower figure became more visually attractive and coherent with its surroundings. The sophisticated use of illumination of the facade elements highlights the powerful and dynamic visual of the tower and simultaneously brings out the perceptible quality of human scale in the building base design.







Avoiding the stereotypes

The building’s envelope serves as a primary contact with the public, therefore it deserves extra attention and care during the design process. To distinguish the tower from all the similar high-rise surfaces, the aim was to avoid the stereotypical arrangement of coloured mullions by designing a mesh structure in front of the facade. Apart from the advantages of a double facade, the image of intersecting lines remind of the urban grid, at one point untangled and pointing towards the sky.
Behind the first contact of the grid, the surface of the tower and was designed using facade elements similar to those used in the project Panorama City, while the base of the building was covered by a window system by Reynaers.
Apart from the standard shading systems applied in the window area, the inner surface of the glazed area is covered by a shading foil applied to eliminate the solar glare and prevent overheating. The pattern for the positions of foil-covered windows was generated by the program Grasshopper, according to the buildings position in relation to capital directions.