Germany's largest Motel One opens its doors
Fiberglass reinforced concrete facade at the Alexanderplatz in Berlin
In early December 2017, the Motel One hotel chain opened its largest property, located at the Alexanderplatz in Berlin. The planners paid meticulous attention to the facade's design, in order to meet the high demands of this widely known location and the hotel operator's corporate architecture.
Alexanderplatz is one of the most important tourist attractions of the German capital. So it's no wonder that this place is also interesting for hotels. At the beginning of December 2017, the Motel One hotel chain opened its largest building here. It is 60 meters tall, has 19 floors and offers about 25,000 square meters of space. While the building houses restaurants, stores and offices on the ground and second floors; the floors above contain 708 Motel One rooms and public areas. The property was planned by the office GFB Alvarez & Schepers from Berlin. In order for it to visually do justice to the prestigious location and the corporate architecture of the hotel chain, the planners placed great emphasis on the facade design. They had to manage the balancing act of integrating the many windows that come with a hotel with over 700 rooms into the exterior in a visually appealing way, while at the same time preventing them from appearing too small. They achieved this in the upper area with a composite thermal insulation facade that is vertically divided by two different shades of gray. For the base of the building - the area that pedestrians perceive the most - they planned facade cladding elements made of fiberglass concrete from the company Fischer & Partner with the product Polycon.
Glass Fiber reinforced concrete
This is a fire-resistant, noncombustible (A1) composite building material made of concrete and alkali-resistant glass fibers. Florian Deppisch, the architect responsible for the project, stated: "We decided to use glass fiber concrete because we had already had positive experience with it. For example, we are convinced by its robustness against external influences and the possibility of adapting it to our color preferences." In fact, Polycon has a very long service life. However, the appearance of the façade panels can be specifically adapted not only in terms of color, but the designer has many more design options. For instance, one may determine the surface finish of the elements himself. These are available in smooth, fine and coarse textured variants. Even reliefs reminiscent of the structure of natural stone, wood or other materials can be realized. For the color scheme, the client can choose between concrete gray or bright white or an individually colored variant (for more, see Box 1). In the case of Motel One, the designers opted for gray-colored white cement to match the color of the composite thermal insulation system used on the floors above the base. The final color was selected by the architects on the basis of sample panels specially manufactured by Fischer & Partner. Additionally, the planners wished to have a seamless anti-graffiti coating.
Thin and customizable
Another important reason why the architects decided in favor of Polycon was the fact that fiberglass concrete can be combined well with the thermal insulation composite system. Florian Deppisch said: "It was clear early on that we would use a composite thermal insulation system on the upper part of the building. The material of the base should therefore be consistent with the surface. With glass fiber concrete, this is possible." Thanks to the added glass fibers, the stability of the concrete increases. Thus, facade elements with a thickness of 13 - 20 mm (depending on the element size) can be manufactured. This means that the construction depth in the base area of the hotel is approx. 21.5 cm (glass fiber concrete + rear ventilation + thermal insulation). A total of almost 770 Polycon façade corner elements and panels were installed. Since they were used in the plinth area, the arcade, the corners, at window areas and also other architectural elements, numerous different shapes had to be produced. Polycon facade elements are manufactured by pressure spraying, which has the advantage that both, flat components and three-dimensional shapes are feasible to manufacture. The largest façade panel is located on the south side of the building and measures 1.99 x 1.73 meters.
GFB Alvarez & Schepers Gesellschaft für Architektur, General planning and Design mbH
Hardenberg str. 4 - 5