Clear floor plans, flexible room layouts and transparency characterize the new headquarters of BFFT GmbH in Gaimersheim. The conceptual and design clarity characterizes not only the architecture but also the fire protection concept, which was implemented in some critical installation situations using fire protection glass in facades and door systems.
‘HQ2’ is the name of the new headquarters of BFFT GmbH in the Gaimersheim commercial area near Ingolstadt - a combined office and workshop building for the company active in vehicle technology and electronics.
On the outside, the multi-layered facade with movable slat shading gives the cubic structure a technical expression - in the core of the building, two green inner courtyards create opportunities for retreat for the employees and ensure plenty of daylight.
For Kandler-Bunje, Architekten & Ingenieure, the design task was to design a new company headquarters for around 500 employees on a site in the Gaimersheim industrial park near Audi AG. The building, which consists of prefabricated reinforced concrete columns and ceilings, contains a wide variety of functional areas: workshops for vehicle development, office space, meeting areas, a fitness studio, yoga room and cafeteria.
Kandler-Bunje has developed a building with generous transparency and clear proportions. The post and beam façade is room-high and glazed all around on all floors from the ground floor to the fourth floor. Only the ground floor on the west side and parts of the north and south sides consist of a thermally insulated, rear-ventilated façade with cladding made of non-transparent Alucobond cassettes.
Glass façade with high-tech character
The glass façade of the upper four floors is covered by more than 520 vertical aluminum slats that serve as sun protection. They also form a second façade layer that creates a strict, regular pattern or a moving image of the inner structure. Six slats in each case, and seven in the corner rooms, correspond to the smallest possible room modules inside and can be individually controlled by the users. However, the slats can also be centrally controlled to follow the course of the sun's rays, thus optimally shading the areas behind them. They not only serve to prevent glare for the workplaces, but also make a decisive contribution to saving energy for cooling the offices in summer.
The fact that the high-tech character of the individually developed façades suits a company in the automotive and electronics industry very well, and is extremely elegant, is a side effect that is both welcome and intended in terms of design.
Flexible division, technology and ecology
A simple and column-free room structure results in floor plans that can be divided extremely flexibly, which are clear and uncompromising for the vehicle workshops, but also for the office structures. The surrounding heterogeneous development consists of buildings with predominantly commercial use. The two inner courtyards of the new building allow retreat and averting from this inconsistency.
Natural ventilation and lighting ensure optimal working conditions in the office and workshop areas. From the first to the fourth floor, the façade has a porch made up of maintenance balconies, to which storey-high rotatable sun protection panels are attached, which automatically track the sun. The sun protection wings give structure and rhythm to the multi-layer building shell, serve as a shading system and at the same time reflect the company's demanding field of activity in their technical appearance. In order to ensure the base load of heating and cooling requirements for the building, the "thermally activated concrete ceiling" system was chosen. Depending on the requirements, cold or warm water flows through the pipes during operation, which leads to a temperature control of the concrete slab at a low level. Due to the resulting large surfaces with low temperature, a high performance for room air conditioning with optimal thermal comfort is made available.
A very efficient system that works energetically with the lowest possible means and energy consumption values.
Space for active and passive relaxation
Two green and weather-exposed inner courtyards direct the gaze away from the optical surroundings of the commercial area and towards the clearly structured common green areas.
An attractive offer for employees who work on the screen every day. The floor-to-ceiling glazing of all office and workshop areas creates optimal working conditions with natural lighting and ventilation. The infrastructure in the immediate vicinity prompted the client to create a fitness studio, a yoga room and a cafeteria for the employees on the 4th floor. The holistic planning of the HQ2, which was well thought out from a functional, energetic and social point of view, ultimately led to the project being included in the exclusive circle of ‘Architektouren 2013’ – an annual exhibition of extraordinary architecture initiated by the Bavarian Chamber of Architecture.
Fire and smoke protection
The building law classification of the office and industrial building with five full floors and a floor area of 2060 m² was based on the Bavarian Building Code (BayBO).
For buildings with usage units of more than 400 m² and floor areas above 1,600 m², it provides for a division into two fire compartments. As a consequence, the building was separated by fire walls, stairwell walls in the style of fire walls, two F 90-A walls on the 4th floor in connection with a spatial separation by the toilet facilities and by the courtyards from the 2nd to 4th floor. The floor area of the largest fire compartment (EG North) is 938 m² including stairwell 3. In addition to this basic structure, there was an additional fire protection subdivision into 15 building law usage units with lounges, the partition walls of which were designed to be at least fire-resistant. All usage units subject to building regulations each have at least two structural escape routes, with the three internal escape routes being necessary stairwells.
The corridors within the office units < 400 m² are not designed as necessary corridors. This seemed reasonable to the responsible authorities for the existing office units of almost 400 m² due to the two structural escape routes, especially since the first escape route has a maximum length of 24 m.
Smoke extraction via the façade
To enable smoke extraction from the 15 usage units, windows covering around two percent of the usable area are installed in the outer wall, which enable smoke to be dissipated.
The windows can also be opened manually. The state of relatively closed slat position is short-lived. At intervals of one hour, the gap width closes and opens from approx. 7 cm to 2 cm and again to 7 cm. When the maximum gap width is reached at a distance of 50 cm, a total of 14% opening in the façade is already possible. In addition, smoke can also rise through the approx. 60 cm wide gratings of the plaster walkways. These smoke extraction considerations led to the omission of an additional fire control system for the slats.
Fire protection with glass
In order to maintain transparency and the high incidence of daylight across the separation of the usage units, door systems in the corridors and at the entrances to the adjoining areas were designed as glazed T 30-2 fire protection system constructions. The WICSTYLE 77FP system from Wicona was chosen in conjunction with Pilkington Pyrostop® glazing of fire resistance class EI 30 to fine-tune the design with the mullion-transom construction of the façade. Undivided, large-area door leaves, in conjunction with skylights, provide partitions that are barely perceptible to the eye but are highly effective in terms of fire and smoke protection. Since the fire compartment separation falls partly in the inner corner areas of the atrium facade, defined fire flashover areas were equipped with fire protection façade glazing. EI 30 façade systems from the WICTEC FP series, glazed with Pilkington Pyrostop® fire-resistant insulating glass, are intended to prevent a horizontal spread of fire to the adjacent fire compartment in the event of a fire. Identical profile views in the façade system and highly transparent fire protection glazing cause that no difference between the standard façade and the fire protection upgraded area is perceptible. And from an energy point of view, the fire protection façade elements are in no way inferior to the rest of the façade, since a Pilkington Optitherm™ S3 outer pane with a thermal insulation coating was integrated into the Pilkington Pyrostop® insulating glass.
Photography: © HGEsch Photography