The three-section sports hall of BG/BORG Graz Liebenau – called BLUE BOX – should be seen as an additional module within the whole complex of the existing sports and school building, which functions, however, as a free-standing building as a result of the strong identity-forming effect of its external appearance. The divisible hall, whose interior is 9 metres high, is sunk approx. 4 m into the ground, to bring the height of the building to a level compatible with the surrounding parts of the complex and with the local residents.
The fixed stands area is designed for 300 people and an additional 6 wheelchair spaces. Three telescopic seating stands enable the capacity to be enlarged by 264 people to a total of 566 spectators. The unity of the hall and sports area is a significant element in urban spatial design: The facade of the hall has the same structured blue surface as the sports area with its rubber coating. The design unity thus produced creates an entrance area in the school grounds, which already has strong associative references to sport. The horizontal caesura in the base, in the form of a glass band that can be illuminated, also makes the structure appear light.
In the jointed, low structure connecting the existing building of the "old sports hall" and the new hall, the entrances and the foyer with a small buffet area and adjoining rooms are located. Through the synergetic use of the existing – and now renovated and optimised – washrooms within the "old" sports hall, the direct connection can also be justified in terms of function for external use in the form of events.
As an anti-glare measure, the sports hall itself is lit naturally from the north side. Additional dome rooflights, which serve the purpose of fume extraction, provide pleasant floor lighting.
Access is designed in such a way that, on the one hand, a strict division is possible between school use and external use by clubs, for example, and on the other hand, between visitors to events and players: External users and organisers/players have access to the sports hall via the running track in the north of the grounds and enter the building from the new north-east forecourt, so that the existing school building is not used and lessons are not disturbed. Access for visitors to events is via the main, central axis of the school grounds and through the new main entrance, on the school side, into the foyer, from where the seating in the stands can be reached and is wheelchair accessible. Pupils and teachers have direct access from the existing building via the stairwell to only the changing rooms and sports halls.
The basement is used exclusively by the athletes and those accompanying them. Via the stairs or lift, you reach a dirty corridor that leads to the changing rooms with washrooms, as well as to the building services rooms and adjoining rooms. One of the three changing room units, which each have two cubicles, is reserved for wheelchair users and equipped with a suitable shower. A washroom and a wheelchair-accessible WC, which is also designed for general use by pupils or athletes during training, complete the facilities. Athletes reach the sports hall from the changing rooms via the clean corridor.