Ready for the market – thanks to an interdisciplinary partnership

A spiral staircase in the shape of a spine produced by 3D printing, a ribbed filigree slab that requires around a third less material and an energy-efficient building envelope that ensures an optimum level of comfort: A new unit is being planned at NEST. STEP2 – as it is called – combines innovations in the areas of circular economy, industrial and digital fabrication as well as building envelope and energy systems. The focus lies on the marketability of new solutions and processes. Accordingly, all innovations are developed consistently and from the very beginning along the entire value chain in an open innovation approach.

"In the STEP2 unit, we work towards marketable solutions. In addition to academic research, various industrial partners are participating in the project. This interdisciplinary collaboration will ensure that market entry can be achieved as fast as possible", says Enrico Marchesi, Innovation Manager at NEST. Andreas Hafner, Principal Innovation Manager at BASF, the unit's main partner, adds: "We are convinced that this project will result in future-oriented innovations that will succeed in the market and promote the sustainable use of energy and resources."

The two-story unit will be built on the top platform of NEST. After completion, it will serve as an actively used innovation workshop, which allows the development of many other innovation projects, and as an office environment. The project team is currently finalizing the preliminary design study so that planning of the construction can begin in 2021.

During the planning phase of the STEP2 unit, the project team relied strongly on experience from existing NEST units. These previous projects had shown that the prefabrication of formwork for concrete floor elements using 3D printing offers enormous potential. "3D printing technology combines the efficiency of industrial manufacturing with the freedom of digital design tools," explains lead architect Silvan Oesterle of the ROK architectural firm.

The team will resort to this technology for the realization of the floor slab in the STEP2 unit. They developed a business case for a marketable ribbed filigree slab in fair-faced concrete quality. It can cover spans of up to 20 meters. For Oesterle, the advantages are obvious: "On the one hand, the floor slab acts as a thermal storage mass during operation. On the other hand, this concept requires one third less material than normal filigree slab. We save resources, reduce weight and at the same time increase cost and energy efficiency." For the market, this represents an innovative prefabrication process allowing the efficient production of floor slabs for solid houses. Stahlton Bauteile AG is convinced of this concept and thus decided to participate as an industry partner. The company will also apply this prefabrication process in its own factory.

Another innovation object is the spiral staircase to the unit's upper floor. Tailor-made concrete staircases pose great challenges to conventional formwork methods. In the STEP2 unit, the team therefore relies on digital planning methods and 3D-printed formwork for the realization of a staircase made of ultra-high performance concrete (UHPC). Its unique shape is reminiscent of a human spine. For its realization, the "Digital Building Technologies" Institute of ETH Zurich as planning partner as well as the two industrial partners BASF Forward AM and SW Umwelttechnik are combining their knowhow. With this challenging example for a practical application, they are putting their processes, technologies and products to the test, which will enable their further development.

Building envelopes contribute significantly to energy optimization and user comfort. However, this potential is often not sufficiently exploited today. The STEP2 unit is therefore focusing on driving the development of innovations in the field of building envelopes. With the help of Aepli Metallbau AG's expertise in this field, the team has designed the façade in a way that allows the replacement of individual elements with minimal effort. This offers NEST partners the opportunity to easily implement and validate new technologies and materials. WaltGalmarini AG has developed a comprehensive energy and building physics concept for the operation of the unit and will further optimize it in the coming years. One central element for the implementation of this concept is the interaction between the floor slab and façade innovations.

Further information on the different innovation objects and regular updates on the development of the unit are available on the STEP2 website.