Project of the month

In the high arch: New Annen Plus factory building

The family business Annen from Luxembourg specialises in the planning, production and installation of innovative window and façade constructions made of wood, metal and glass. The company sets itself apart from the competition with its modular timber constructions in particular. Annen is demonstrating its own expertise with a prestigious company headquarters: the new factory buildings consist of 23 wooden arches, which are based on the principle of a unique surface structure. Encased in a Kalzip system, the building is protected from environmental influences.

Podcast episode:

Lightweight construction meets sustainability

Together with Yves Weinand Architects, who contributed their expertise in timber construction, VALENTINY hvp was able to plan and realise the design in a unique way. It was also particularly important to company owner Alois Annen to construct a building that was as sustainable as possible: “Part of our company philosophy is to construct buildings with the smallest possible ecological footprint. Sustainability starts with aesthetics – if a building does not fulfil aesthetic requirements, it is not worth preserving.”

The combination of advanced timber technology and innovative metal roof technology makes this project unique. The large, self-supporting timber construction required a lightweight roofing system to minimise structural stress. Made of aluminium, the Kalzip system makes a significant contribution to structural efficiency by having a particularly low dead weight compared to other systems. At the same time, the material is extremely robust and contributes to the longevity of the building envelope. The Kalzip standing seam system is also a good choice in terms of sustainability. The material used consists of aluminium with a recycled content of 98 percent.

Computer-generated timber construction

The central concept behind the new factory building is based on the principle of parametric construction. This method allows highly complex constructions to be realised precisely, flexibly and error-free using parametric 3D planning. The components are first digitally designed and converted into production information. A computer-aided process then takes over the production of the individual components, which are finally assembled with a perfect fit.

As a branch of Yves Weinand Architects, the Bureau d’études Weinand in Liège, Belgium, is dedicated to timber construction engineering. The parametric codes for the wood-wood connections were developed together with researchers at the Chair of Timber Structures (IBOIS) at the Ecole polytechnique fédérale de Lausanne. “The IBOIS researchers have done a great job in the parametric design of the timber components. Various prototypes of the timber arch structure were also built at the institute to test design, assembly and structural integrity. A 1:1 scale prototype ultimately withstood the mechanical load tests. So we knew we could safely pass the data on to Annen,” reports Yves Weinand, Managing Director and founder of Yves Weinand Architects and Bureau d’études Weinand. Production and assembly on the construction site in Manternach were then carried out by Annen itself.

Design requirements fulfilled

Once an arch had been completed, it was time for the outer cladding. Specially developed for projects such as this, XT free-form profiles from Kalzip were recommended, which are characterised by their flexible formability. Advanced 3D modelling programs enabled detailed digital planning and the precise unfolding of the three-dimensional geometries into two-dimensional patterns. A brown-metallic colour was also chosen for a sample.

As the building slopes to both sides and the profiled sheets here have an increasingly shallow angle of inclination towards the ground, a change in the standing seam arrangement from the centre of the roof had to be taken into account. The standing seams are now positioned on top of each other on both sides of the building so that the large seam encloses the small one from above. This prevents water from penetrating the structure even during heavy rainfall.