A crystal that reflects the elements of the outdoor space in daylight and shows its inner radiance in the dark was the inspiration for the new central building on the Sartorius Campus. The lighting designers from Studio DL worked together with the architects Bünemann und Collegen right from the concept phase. The lighting design relies on architecturally integrated lighting. Thanks to excellent programming, the lighting adapts to the times of day and the daylight conditions in an energy-saving and employee-centered manner.
The glass forum is the latest building to be completed within the master plan developed by the Hanoverbased architects for the 170,000-square-meter Sartorius Campus. The new building combines laboratories, conference and training rooms, a company restaurant for up to 3,000 employees and visitors, and approximately 350 office workstations on the upper three floors. The lighting of the forum is part of the master plan that the lighting designers had conceived for the campus and the outdoor facilities.
The influence for the exterior design of the Forum is a crystal, which reflects its surroundings in constantly varying light conditions and brings them together in its view. This is clearly visible in the design of the glass “envelope” and the angular shape of the building with its bends in the facade. At Sartorius AG, the crystal is representative of a lively and dynamic company.
Motor-controlled glass louvers for natural ventilation are integrated into the fully glazed outer shell of the double facade with panes up to three meteres wide and up to 5.80 meters high. The walkable and naturally ventilated intermediate space behind it serves as a thermal buffer zone, which is closed to the building interior by a thermally insulated facade. Windows that can be opened individually and insulated metal panels are integrated into this glazed interior facade. These elements and the layers of the facade together provide good natural ventilation as well as effective thermal insulation all year round. Above all, however, the large glass surfaces create transparency and excellent daylight conditions in all rooms.
When viewed from the outside, the metal panels in the interior facade prove to be architecturally defining elements that inspired the lighting designers to create the design motif for the entire forum. By means of invisible light lines, they illuminate the metal panels on one side with scattered light. The brightness of the light, which decreases in the direction of the crystalline tips of the building, animates the seemingly self-luminous metal discs and thus underscores the architectural gesture. While the light is dimmed depending on the time of day, the luminaires switch off completely at night.
Inside the building, the design element of the pane transforms into a line by reducing the width, which is used as an orientation and structuring element.
The literal heart of the building is the atrium, spanned by a glass roof with a steel structure, which opens up the four floors of the new building with suspended cascade-shaped stairs and connecting walkways and at the same time serves as a meeting place. Due to its luminous architectural surfaces and the perfect concealment of light sources, the atrium seems to radiate by itself. Individual, structurally complex luminous ceilings were made for the lower elevations of the connecting walkways. The short installation height of just under 15 centimeters, with the need to integrate both acoustic damping and emergency lighting, presented an enormous challenge.
Visible light sources were also omitted in the illumination of the triangular steel infill panels, which filter and diffuse the incident daylight. They are equipped with particularly narrow V-shaped light lines that brighten up the ceiling structure in the evening, referencing the sky light and demonstrate the height of the space.
The offices located on the three upper floors of the Forum were planned as daylight-flooded open areas with team workstations, and special luminaires for Human Centric Lighting equivalent to those used in the office buildings completed in previous years. The spacious office structure is divided by meeting rooms, a few individual offices, think tanks, printer stations, kitchenettes and acoustically shielded seating. Ceiling sails are installed above the workstations to create a quiet, noise-reduced working atmosphere, and their effectiveness is enhanced by further acoustic interventions.
In addition to daylight, the office zones are illuminated exclusively by individual workstation luminaires that are integrated into the storage space furnishings next to the height-adjustable workstations. Here, too, the planners attached great importance to the concealment of the light sources and, together with an experienced manufacturer, developed a luminaire that conceals its light source in a technically sophisticated manner.
When employees switch on their workstation luminaires individually, the office is illuminated exclusively by indirect light. The programming, which cannot be overridden individually, ensures a dynamic progression throughout the day that supports the human circadian rhythm and thus the well-being of the employees as naturally as possible. The color temperature is based on the course of natural light with a warm 2,700 Kelvin in the morning, a cool 5,000 Kelvin at midday, and again 2,700 Kelvin in the evening.
The automatic dimming of the indirect light takes place in conjunction with the current daylight entries. In this way, the workplace areas are always illuminated with 500 lux in accordance with the standard. If necessary, a direct light component can be switched on individually. Monitoring has shown that this is rarely used. During normal working hours, the balanced indirect lighting is completely sufficient and is also very well accepted.
The luminaires are interconnected to prevent the formation of a light island, providing a comfortable and economical lighting atmosphere. When the indirect light of a single workstation luminaire is activated manually, the light of the neighboring luminaires is automatically switched on in a highly dimmed state. This makes for a more comfortable atmosphere and, thanks to the dimmed state of the ambient luminaires, the lighting remains within economic limits.
Thanks to the close cooperation between architects and lighting designers at an early stage, the Forum of Sartorius AG has succeeded in consistently implementing an architecturally integrated lighting concept. The architecture of the light-filled rooms is not distracted by visible luminaires or light sources and the atmosphere is highly accepted by the employees. In the staff restaurant, ceiling-integrated spotlights and large pendant luminaires were used to create selective accents to differentiate between performance and relaxation phases during the working day.