Ring cycle

This unorthodox-looking office building on the outskirts of Gniebel houses a software company consisting of 250 employees. The greenfield site is typically placeless yet well connected, on the edge of the motorway linking Stuttgart with Tubingen. Kauffmann Theilig & Partner are acquiring a reputation for innovative office design, based on an ability to combine bold form with energy-conscious environmental control strategies (for example their proposal for Glasabu Seele's headquarters, AR May 1995). Here the aim was to create a building that would nurture creative collaboration between employees as well as incorporate a degree of energy and ecological consciousness.

The five-storey building is organised around a doughnut-shaped plan. The squat yet sculptural circular form makes a strong impression in the landscape, reinforced by the raw materiality of the concrete structure and its timber cladding. This gives the building an engagingly robust, ark-like quality, far removed from the slick blandness more typically associated with corporate headquarters. Wide balconies project from the upper two floors and the entire ensemble is capped by an oversailing roof. The circular plan is intended to break down traditional management hierarchies and encourage a sense of workplace communality.

Rings of offices, some cellular, some open plan, enclose a generous, cylindrical atrium which forms the building's spatial and social focus. Each cluster of desks or cellular offices also has direct access to the balconies that run around the building, so that workers can enjoy a change of scene. As well as providing informal social spaces, the balconies and overhanging roof also help to diffuse distracting glare on computer screens.

The building's entrance is indicated by a glazed wall (a surprisingly delicate insertion in the building's curved timber and concrete hull) that gives enticing glimpses into the atrium beyond. The four-storey atrium drops down one floor, below the level of the entrance, and is bisected by a system of bridges and stairs linked to galleries running round its edge. The dividing walls between the offices and the atrium are glazed, primarily so that daylight can be brought into the offices, but also to generate a sense of animation and openness. The only enclosed elements are the modular pods housing the lavatories and fire escape stairs.

The environmental control strategy relies on natural ventilation, thermal mass and exploiting the considerable waste heat from computers and telecommunications equipment. The offices are mechanically ventilated using fresh air which is ducted into the atrium and through into the adjoining office spaces. More remote offices are serviced through a pipe system and floor vents. A ring-shaped duct running along the external facade collects the return air. During summer, fresh air is collected and cooled in an underground duct, to around 7 degrees Celsius, and return air is exhausted over the roof. In winter, the return air is collected and helps to pre-warm the air supply; this process is also supplemented by heating units. Exposed areas of concrete act as thermal mass.

During the design phase, the building's annual energy requirements were predicted by computer modelling at around 215 kW/sq m, roughly one quarter of the consumption of a conventional building. Obviously this may be subject to variation once the building is properly monitored and in use, but it also offers encouraging evidence that the modern workplaces can be energy efficient as well as humanely scaled and organised.

COPYRIGHT 1997 EMAP Architecture
COPYRIGHT 2008 Gale, Cengage Learning