Many ways for the public to dwell and linger

Benches for the Europaallee

Following a public tender, SBB commissioned BURRI to develop and produce a series of custom benches that intended to invigorate the public space on Europaallee and provide a space to linger.

In the design process, the landscape architects Krebs und Herd placed particular emphasis on sustainable, high-quality materials and the straightforward interchangeability of all components. Together with Krebs und Herd, BURRI has developed a bench especially with this new urban space in mind. The outdoor furniture can be easily maintained thanks to its modular system, and entire sets of slats can be replaced as a single component in a few simple steps. As is standard at BURRI, the long-term availability of spare parts is guaranteed.

The modern design of the seating constitutes an identifying feature for the square and, as such, promotes people’s active participation in the public space. The benches are fitted with the locally grown “exotic wood” NATWOOD®. This wood product from BURRI is made using local timber stocks and employs a special refining process that makes it as resistant as tropical wood.

Last but not least, the specially designed cast-aluminium corbels are genuine eye-catchers. These are screwed to the custom-made base frames and attractively round off the side contours of the seating. BURRI assembled the finished benches in several stages on site at the Europaallee.

Making of

Competencies deployed in development: 
Design and prototyping
Installation and maintenance
Materials and technology

Development

In the preliminary project, BURRI worked together with the architects to define important cornerstones for the development phase and to incorporate trendsetting approaches ahead of time. In this way, the team was able to clarify the feasibility of a modular system for long long-term maintenance requirements and could specify both the structure of the base frame (including surface engineering) and the appropriate choice of wood – all well in advance.

A particularly intricate challenge was the manufacturing of the curved cast-aluminium corbels, which serve both as supports and as aesthetic elements for the bench ends. The team agreed on the aluminium sand casting process as the most effective approach. The application of this approach in large linear dimensions required in-depth knowledge of the respective manufacturing techniques and materials. For the production of the cast corbels, impressions were made from two negative mould halves using a special sand-oil mixture. During the casting process, air channels in one of the mould halves enabled outgassing and the optimal distribution of the liquid aluminium. To ensure consistent cast quality, the casting temperature of the liquid aluminium had to be perfectly tuned to the temperature of the casting mould.

Prototype

Following the development phase, the prototype construction phase once again resulted in a number of individual improvements in the subsequent series production. Furthermore, during this stage it was possible to create samples of the metal and wood surface finishing and determine the definitive seating geometries. BURRI then subjected the specially manufactured, effectively series-ready prototypes to stress testing in public outdoor spaces over a period of several months.

Production

Across several stages, BURRI produced a total of 250 linear metres of the large benches in seven different seating typologies. Due to the size of the benches – in some cases over 16 m long – as well as complex logistics, it was essential that the final assembly at the specific locations was correspondingly accurate and diligent. The components required to manufacture the benches were produced in close cooperation with specialised suppliers and partner companies using just-in-time logistics, with final component assembly taking place at BURRI. A crucial factor in the production of these modular benches is the high accuracy of fit and precision. This necessitated the creation of special gauges for the production of the base frames and the millimetre-precise fastening of the wooden fittings. Before delivery, test templates were used to double-check the accuracy of the fit and interchangeability.