The geometric rectilinearity of the cube, devoid of any projecting elements, is further emphasized by the clear articulation of the facade. The architects designed a facade cladding in a random bond pattern with concealed fastening using extra-large slate tiles. Seven-millimeter-deep, undercut blind holes were drilled into the back of the 2-centimeter-thick tiles, into which the undercut anchors are inserted, creating a form-fitting connection free from expansion forces. In combination with the flush-mounted window bands, this resulted in a homogeneous, surface-emphasized facade that optimally showcases the design concept of the slate block. The architects consistently continued this clear design language in the interior. Slate was also used as wall cladding in prominent areas. Smooth white surfaces and matte-lacquered oak wood provide a harmonious complement.
In addition to the distinctive facade, a contemporary energy concept plays a key role in the overall design. It is based on reducing energy losses through the highly insulated building envelope (a ventilated curtain wall facade with 16 cm of mineral wool) and the resource-efficient use of geothermal energy as a heating and cooling medium. A heat pump generates 35°C hot water from the approximately 10°C geothermal heat. This heats the concrete ceilings to approximately 20–24°C. Convectors with integrated ventilation outlets under the windows allow for a rapid response to individual temperature adjustments, complementing this slow-reacting system. The same principle is used in reverse for cooling the building in summer. Triple glazing with solar control glass and an automatically controlled sunshade system prevents excessive solar radiation into the building and supports the system. Additionally, all rooms are supplied with fresh air via a controlled ventilation system with heat recovery. The building's energy consumption is below the requirements of the currently valid German Energy Saving Ordinance (EnEV).
