Photo: © 2021 by Joerg Hempel
The Mercator One, in the heart of Duisburg, is the first building in Germany with a façade created from End-of-Life Hydro CIRCAL aluminium. The office and commercial property designed by Hamburg-based Hadi Teherani Architects is not only impressive in terms of sustainability, but its façade is also architecturally stunning.
Situated directly on the centrally located Portsmouthplatz in Duisburg – between the pedestrian zone and the main railway station – this construction project is, quite literally, “trailblazing”. With its distinctive fan-like rearward-pivoting façade and floor-by-floor tiered projections, the Mercator One immediately catches the eye and simultaneously guides you into the city. The anthracite grey façade cladding gives the building a restrained character despite its striking appearance, while the generous glass surfaces imbue it with transparency and a sense of lightness. At the same time, the façade’s extraordinary silhouette, which continually reveals new and surprising perspectives, makes this building – which measures approximately 100 metres long, 17 metres wide and 26 metres high – a landmark in the surrounding urban area.
The ground floor of the new building is 9,500 square metres, providing plenty of space for offices or for gastronomic or retail use. The structure of the building allows for a flexible floorplan design and is highly adaptable for all types of office concepts. For optimum user comfort, the building offers different city views which emerge in turn from the building’s lateral graduations and the fan-like twists of its main section.
Sustainability as a key decision-making criterion
The client, Torsten Toeller – CEO of Fressnapf Holdings – placed great emphasis on environmentally conscious construction and a long-term, sustainable concept for Mercator One. All of this is reflected in the Hadi Teherani design. As lead architect Bernd Muley explains: “Our focus is always the environmental aspect. The Cradle to Cradle (C2C) principle is integral to our work. For example, when we select materials for a building, we also consider – besides the architectural aspects – where the material comes from, how efficient its manufacture is and what becomes of the material at the end of its life”. With this in mind, the client and architect turned to WICONA systems when creating the distinctive façade of Mercator One and used Hydro CIRCAL 75R – a sustainable aluminium alloy, unique on the market, with a minimum End-of-Life (EoL) recycling proportion of at least 75%. The aluminium comes from demolition projects or from old cars, for example. This is material that has already been used once and has been returned to the production cycle. As Bernd Muley puts it: “Recycled aluminium has the same properties as new and is also extremely sustainable. It requires only 5% of the energy used for the production of new aluminium.
Smart façade design
The proven WICTEC 60 mullion/transom system proved to be the perfect solution for the façade, given its architectural and constructional requirements. It meant that the floor-by-floor tiered graduations and projections planned for the main section could be implemented using the flank offset of the mullion profiles – laterally parallel with the concrete soffit.
The strong deformations of up to 50 mm over the entire width of the building are proportionally absorbed in the profiles. The façade was also extensively fitted with crash-resistant glazing and a filigree profile width of 60 mm. All the windows were constructed using the WICLINE 75 evo system – and equipped with concealed turning sashes that include crash-resistant opening limiters. As Peter Hemmert, the WICONA project consultant, explains: “The passive house-compatible construction with a very low construction depth of just 75 mm is provided with an ETC insulation zone without foam filling, and therefore helps to meet the client’s stringent sustainability requirements.”
An outstanding iconic project
Mercator One was completed in 2020 and has since won the Bund Deutscher Architekten (The Association of German Architects) prize for North Rhine-Westphalia, Right Lower Rhine. And according to architect Bernd Muley, recycled aluminium will continue to play an increasingly important role in façade design in the future. “Mercator One is the first of its kind in Germany. I hope that the project will serve as a role model and that it will inspire other architects to use sustainable aluminium.”
Project: Mercator One office and commercial property (Duisburg)
Client: DEVARIO (represented by SK62)
Architects: Hadi Teherani Architects GmbH (Hamburg)
Façade construction: Rupert App GmbH & Co. (Leutkirch)
Façade system: WICONA
Photos: © 2021 by Joerg Hempel