The Cluster of Excellence for Integrative Computational Design and Construction for Architecture (IntCDC) at the University of Stuttgart is appearing at the State Garden Show with two future-oriented projects. The Wangen Tower and the Hybrid Flax Pavilion demonstrate the potential of bio-based materials in the field of sustainable architecture. Both designs were planned according to the latest findings in digitalization and lightweight construction research. Both buildings are open for visitors to experience as part of the Landesgartenschau until October 6th, and will remain accessible on-site even after the exhibition concludes.
"The Wangen Tower and the Hybrid Flax Pavilion are the result of many years of research by the Cluster of Excellence. The buildings were constructed in cooperation with local companies. This will facilitate the exchange of knowledge between research and construction companies, with the goal of ecologically optimizing construction processes. In doing so, it lays crucial groundwork for the construction industry's transition towards sustainability," says Professor Achim Menges, spokesperson for the Cluster of Excellence Integrative Computational Design and Construction for Architecture (IntCDC).
After ten months of planning, the Wangen Tower and the Hybrid Flax Pavilion were inaugurated on April 26, 2024. The integration of computer-based planning methods and digital manufacturing processes has enabled the creation of differentiated, resource-saving constructions that can be dismantled and reused. They demonstrate to visitors various ways in which bio-based materials facilitate innovative approaches to regenerative architecture. Both buildings are open for visitors to experience as part of the Landesgartenschau until October 6th, and will remain accessible on-site even after the exhibition concludes.
Hybrid Flax Pavilion: Resource-saving wood-natural fiber hybrid system
"This pavilion is the first building in the world to use natural fibers in this way. The snow load that the pavilion in Wangen has to bear is up to 360 kg/sqm, which is exceptionally high," says Professor Jan Knippers, Head of the Institute of Building Structures and Structural Design at the University of Stuttgart.
The Hybrid Flax Pavilion is a central exhibition building at the Landesgartenshau, surrounded by the renaturalized River Argen. The pavilion is the first to showcase a hybrid construction of wood and natural fibers as an alternative to conventional construction methods. The pavilion combines slender cross-laminated timber with robotically wound flax fibre bodies in a novel, resource-saving load-bearing system made of regional, bio-based building materials with a distinct local connection. Flax was historically processed in the local textile industry, whose old spinning mill site was renovated as part of the Landesgartenschau. The undulating roof, together with the circular floor plan and the centrally located climate garden, offers a space that merges seamlessly into the landscape.
Wangen Tower: Slender and efficient timber construction
With an impressive height of around 22 metres, the Wangen Tower offers breathtaking views over the Allgäu and the Alps. It is the world's first accessible tower to use curved cross-laminated timber components that self-shape as the wood shrinks. The tower's load bearing, spiraling timber structure offers a unique spatial experience and, with a material thickness of just 130 mm, represents a resource-saving and at the same time high-performance timber structure.
The Wangen Tower and the Hybrid Flax Pavilion are not only real highlights for visitors of the Landesgartenschau in Wangen, but also deal with a wide range of research aspects related to sustainable construction and building production. On September 3, 2024, researchers from the Institute for Computational Design and Construction (ICD) at the University of Stuttgart presented the Wangen Tower and the Hybrid Flax Pavilion at the Holzbau-Offensive BW conference at the Landesgartenschau in Wangen. David Stieler and Christoph Zechmeister, research associates at the ICD, explained to the specialist audience how the Co-Design method is used to develop digital material and construction systems in research using computer-based design and robotic processes. In addition to presentations that examined planning and production in detail, the focus was on discussions with the specialist audience and a tour of the two buildings.
On Friday, 14 June, the timber construction symposium took place in Wangen, where the new building demonstrators of the Cluster of Excellence IntCDC – the Wangen Tower and the Hybrid Flax Pavilion – were presented to the specialist audience. Wangen's Lord Mayor Michael Lang welcomed around 120 guests and praised the innovative power of the buildings, which have been attracting the public since the opening of the State Garden Show in April.
The buildings were presented by the project teams led by Prof. Achim Menges and Prof. Jan Knippers from the University of Stuttgart, as well as the industrial partners Blumer Lehmann, STERK abbundzentrum and HA-CO Carbon. The focus of the presentations was on the reports on the tight planning period of just ten months, which provided valuable insights for planning, production and assembly. Close cooperation and joint development with industry partners ensured the transfer of knowledge between research and practice.
One challenge for the timber constructor Blumer Lehmann was the precise bonding and pressing of the wet timber that was produced for the self-shaping timber components of the Wangen Tower. Bonding the three-dimensionally curved component connections after the self-forming process and applying the required contact pressure was just as demanding.
In contrast to the prototype from the research work, HA-CO was able to dispense with a robot and use a conventional winding machine for winding the flax components. The winding machines were controlled by dynamic, self-calculating paths at runtime, which minimized the input of control data. The small regional timber construction company STERCK was also able to manufacture the timber components of the hybrid flax pavilion from cross-laminated timber: using standardized planning software for timber construction and a conventional joinery system, the roof components for the curved roof were prefabricated at the factory and assembled on time.
Lena Jauernig
Editor Research / Early Career Researchers