Fritz Tower
The facade of the high-rise residential building designed by the architecture office Sauerbruch Hutton in the centre of Berlin sets design standards. Glued to a thermal insulation composite system, it consists of only three ceramic elements from the "Craft" series of Agrob Buchtal: a threedimensional "V-pointed profile strip tile" in ochre-yellow and muted white as well as specially manufactured nosing tiles for the corners of the building.
Apartment building as a landmark
The new Lehrter Straße quarter is located just a few hundred metres north of Berlin's main railway station. It was developed over the last seven years on the basis of an urban master plan of the architecture office Sauerbruch Hutton and has transformed a former wasteland into a vital residential quarter with around 1,000 rented and owner-occupied flats. The architects developed a building structure consisting of six- and eight-storey individual buildings which zigzag along a railway line. Situated at the neighbourhood square with shops and pubs, the Fritz Tower marks the geographical and communal centre of the new quarter, which is visible from afar. The high-rise residential building with partly 8 and partly18 storeys houses a total of 266 micro-apartments measuring between 21 and 47 m². In addition, the building offers amenities such as e.g. a concierge service, a coworking space, an in-house gym and a public bistro.
A multi-faceted ceramic facade
The eye is caught by the ochre-yellow ceramic facade, whose unobtrusive sheen clearly sets it apart from the plaster facades of the neighbouring houses already from a distance. Anyone approaching the Fritz Tower from Lehrter Straße via the neighbourhood square experiences a slender high-rise building which rises evenly with windows elegantly routed around the corner and horizontal metal strips repeated every two storeys. "In pleasant contrast to this uniformity are the irregular light reflections which give the homogeneous building envelope an ever-changing appearance, depending on the viewpoint, the incidence of light and the time of day", explains Louisa Hutton.
The facade is also given a certain lightness by the many short white stripes which condense into long vertical lines in the plinth area and thus contribute to anchoring the high-rise building visually in the ground without any change of material.
Functional and aesthetic
The architects decided on a glazed ceramic facade for three main reasons. "On the one hand, the material is robust, resistant and easy to clean - this is particularly important in high-rise construction, because it minimizes the number of maintenance and cleaning operations which can only be carried out under difficult conditions", says Vera Hartmann, the architect in charge of the project. "On the other hand, ceramics is a natural material that essentially consists of clay and conveys a homely warmth with its haptic surface qualities." The latter is particularly true of the strip tiles of the "Craft" series, whose glossy glaze reflects an astonishing depth and handcrafted manufacturing processes. The third reason for the ceramic strip tiles designed as V-pointed profiles is the comparatively cost-effective facade structure: the thin and light-weight elements form the ceramic "top layer" of a thermal insulation composite system which meets current energy requirements.
Building corners to perfect the form
The high conceptual standard is also reflected in the corners of the building. Their perfect formation was essential for the architects in order to make the ceramic covering appear as a homogeneous, tailor-made ceramic suit, rather than as a thin facade surface simply added on. It was therefore out of the question to simply butt the strip tiles together at the corners or to mitre-cut them and glue them together to form a corner profile. Instead, Agrob Buchtal developed in cooperation with Sauerbruch Hutton asymmetrical nosing tiles which matched the V-pointed profile strip tiles of the facade surfaces both dimensionally and aesthetically.
In order to optimally implement the design ideas, the ochre-yellow basic facade colour was also developed according to the architects' ideas. For determining the appropriate glaze colour, workshops were held in the Agrob Buchtal glaze laboratory,where more than 16,000 different recipes for project-specific individual glazes have been created to date. These workshops resulted in several samples and test areas. In the end, Sauerbruch Hutton succeeded in translating the client's wish for a shiny golden facade into a solution which is elegant, durable and of high quality even without any direct reference to this precious metal.
