Offices facing the Bassins à flot in Bordeaux

The Bassins à Flot district, whose industrial activity is still present in some places, concentrates nautical activities, small companies, and a rich network of associations, but also abandoned areas with a largely degraded industrial heritage. The place is reminiscent of a port imaginary carried by striking figures in the landscape: cranes, barges, rails, silos, etc. The arrival of the tramway requires a redefinition of this district, which for a long time had been excluded from the dynamism of the city centre. As the crossroads of the Bacalan and Chartrons districts, it is part of a global dynamic between the Aubiers urban renewal projects, the new Lucien Faure axis, the Chaban Delmas Bridge and its cut-off point towards the Brazza district. This immense void, a real breathing space in the middle of the city, is then envisaged in continuity with the docks of the Garonne River, as far as the lake. This office project has the particularity of accommodating shops on the ground floor and 70 parking spaces in the heart of the building (invisible from the street). The project is sequenced in three longitudinal strips: an "urban" strip linked to the street, a strip linked to the "large landscape", facing the Bassins, and a central strip, which accommodates the outdoor spaces. The two main strips of 13.9 metres on Rue Lucien Faure and the quay house the shops and offices, while the central strip of 16.6 metres houses the car park, the technical premises, the patio and the terraces accessible at the heart of the block. The 1,600 m² of retail space is distributed around the perimeter of the plot on the ground floor. The whole of the ground floor, open to the public space, is transparent. The offices are located on the upper levels, from the first floor to the eighth floor. In the centre, the two-storey car park (ground floor and mezzanine) and the technical premises are accessible from the path and the new road. The whole, in super-structure, is not visible from the street. The two main bands are crowned by a shed roof, creating double-height office spaces on the lower level, and offering wide panoramic views over the Bassins. The twin buildings are overhung by two turrets: an seven-storey turret for the band on the basin side, and an eight-storey turret on the street side. The turrets aim to introduce verticality to the very horizontal silhouette of the district. They offer the offices 360° views of the Bassins, the Garonne River and the main features of the landscape (hillsides, Aquitaine bridge, churches). The last level, designed as a lookout, is treated by wide terraces generously open to this landscape. Their positioning is established according to an urban logic in the corners of the building, while respecting the volumetry of the sheds. Moreover, they are integrated into the typology of double-sloped roofs present along the entire length of the Bassins. The treatment of the attic (continuous vertical spines, work on the underside) and the façades also ensures continuity. The building is clad in zinc, in reference to the port environment of the site. Natural and lively, this raw material makes it possible to cover the roof and façade with a traditional and unique construction system, while varying the shade of the twin buildings. Full-height zinc spines reinforce the vertical lines of the building, and their triangular shape ensures an effective passive solar protection function. They form large windows, providing users with comfort through an abundant influx of natural light. Similarly, these sunshade spines join the roof at the level of the lookouts and create windows facing the city. The proportion and system of shading varies according to the orientation of the main façades, allowing for optimal comfort of the work spaces and unobstructed views. In keeping with the spirit of the site's industrial past, wide external staircases cling to the facades while providing outdoor spaces on all levels of the turrets. The central strip, treated in raw concrete, reinforces the vision of the three sequences of the building. The central terrace is on the first floor, covered with a wooden deck and punctuated with planters planted in strips. These are transformed into seats to offer users places to relax. The building is designed with a concrete post and beam structure. A distribution slab is installed on the ground floor to allow a wider structural grid for the shops and the car park on the ground and mezzanine floors. We find a grid of 5.40 metres on the current floors and a grid of 10.80 metres on the ground floor and mezzanine. The facade overhangs are divided into 1.35 metre grids, allowing for total flexibility and scalability of the office floors. The two circulation cores, controlled from the halls, extend into the turrets. They allow the bracing of the building, which is subject to strong seismic constraints. The distribution of fluids is carried out solely in the plenum of the false floors, thus freeing the undersides of the slabs from any technical equipment.