Wientalterrassen: An award-winning residential precast project
The concrete table on the top floor of the Austrian company Sonnenschutz Rainer floats gracefully like a feather. But the designer piece of furniture is more than just an architectural eye-catcher – it demonstrates the possibilities of modern precast construction.
Made from just two precast concrete elements, it weighs a total of 16 tons and is 8.5 meters long. Based on a bold design by SONOS Architektur ZT-GmbH and the static concept from the office Bauplanservice GmbH, HABAU Hoch- und Tiefbaugesellschaft m.b.H. was responsible for the planning and production of the concrete elements. The result of this unique collaboration is a timeless piece of furniture that attracts the attention of guests.
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Allplan enables architectural freedom and precision
The planning and execution of this project required a high degree of precision. The focal points had to be calculated exactly, the construction tolerances had to be kept to a minimum, and the assembly had to be carried out with millimeter accuracy. For this demanding task, HABAU relied on Allplan AEC and its integrated precast functions, which enabled the precise design and detailing of the precast elements. The design of the precast elements took around ten working days – proof of the efficiency and precision made possible by Allplan.
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HABAU pushes the limits of what is possible
Special attention was paid to the exact alignment of the precast elements to prevent the table from tipping. A planted raised bed served as a counterweight, providing the necessary stability and adding a touch of nature to the modern design. The high point loads of eight tons each on the poured-in-place concrete slab were also handled through careful planning and execution.
Complex turning of precast elements without lifting anchors
Turning the precast concrete elements was another challenge that the HABAU team overcame with flying colors. Special steel structures and transparent spacer and support plates were used to turn the elements without damaging them, thus preserving the flawless surface of the concrete elements. The assembly was also simulated to ensure an optimal result.
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The concrete table is not only an architectural masterpiece, but also a technological highlight. With electronic heating elements and LED strips that can be controlled via smart home technology, the table offers individual lighting and heating. These features make it a popular meeting place for employees and guests, even during the cold winter months.
In summary, concrete was the ideal building material for this project. The material allowed the tabletop to be cantilevered despite this unusual size, creating a column-free design. The table also blends seamlessly into the overall design of the modern corporate headquarters. Discover how HABAU overcame the design challenges in this case study.
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