Alvéole 12 is a multipurpose hall built into an existing submarine bunker complex.
Two alvéoles and a service bunker were used to create the complex
A new hall was built in the existing bunker by incorporating a prefabricated structure, i.e., a box-in-box construction. The hall is 80 meters long and 17 meters wide.
Next to the hall, a smaller narrower Alvéole 12bis (80m x 8.6m) serves to house kitchens, sanitary facilities, checkroom, lodges and technical rooms, these rooms are built into the space, the old bunker is still visible, in the alvéole 13 next to it (80m x 20m), offices and a large warehouse have been built, as well as a fixed concrete stand for 300 people, here too the old bunker is fully visible.
The hall serves for all activities organized by all 700 associations of St-Nazaire.
The hall can serve for seated performances up to 1000 people and for standing performances, concerts, etc. up to 2800 people.
The hall is divisible by means of two acoustic folding walls that descend from the ceiling to the floor.
The hall has a large raised stage, equipped like a theater/concert hall.
A total of 23 computer-controlled pulls hang above the stage and in the auditorium, the sound system has separate hoists.
The hall is equipped with a complete lighting system (dim/switch) which allows both classic and LED lighting.
Across the hall tucked away behind opening wall panels are several signs with power supplies.
The hall is now used for both classical and amplified concerts, theater performances, musical, dance performance, fairs, exhibitions, bingo nights, parties, parties, courses, etc.
Thanks to a clever supply system and a sophisticated warehouse, the hall was quickly converted with a minimum of personnel.