In Nova Tower
At the centre of Bordeaux, just a few steps from the TGV station, a new office and residential building and outstanding architectural work of art catches the eye: One cube is built onto another in a seemingly precarious equilibrium. Ciments Calcia, a HeidelbergCement subsidiary in France, supplied around 900 m3 of concrete and precast concrete to the top-notch building.
The design: a real eye-catcher
The In Nova tower rises to a height of 55 m – a striking height in a city in which most buildings are only up to 50 m high. Bernard Bühler and Hobo are the architectural practices that have designed the tower and it had been their idea to simply stack the parking spaces, the offices and the apartments onto one another.
The building’s outside plays with the technical restrictions that lie upon high buildings – leaving them behind by the construction method of two cubes that are built above each other, the upper cube positioned slightly offset to the side. The cube containing the office spaces is the basis. The second cube with the residential spaces is completely detached from this basis.
But not only are the two levels separate from one another in a physical sense, also visually, the levels are clearly distinct. The lower building’s facade is smooth, with embedded windows of different shapes and sizes while the upper building has a regular, glazed facade.
The architectural artwork was built by Groupe CARLE, a group that functioned as constructor and building promoter. It houses 150 parking spaces, 9 levels of offices with a total area of 6,700 m2 and 4,000 m2 of residential area on 7 levels, which is divided into 33 one- to three-bedroom flats sized 46 to 175 m2. The costs for the building, which was finished in 2019, amounted to €37 million.
The construction: a giant-sized puzzle
450 m3 of ready mix concrete and 480 m3 of precast concrete were needed for the building. By using precast concrete elements, it could be stacked together like an oversized puzzle.
“To create a building envelope in white concrete, we used the CEM I 52,5 cement from the Ciments Calcia plant in Cruas,” explains Simon Garnier, who is the Managing Director of the precasted building elements company Soriba. “This is the only white cement that delivers appropriate characteristics, performance and regularity of colour and quality needed for an optimal result. At present, it is the best cement. We then added aggregates with a light grey colour to give the 2.422 m2 facade with its 146 7,5 x 3,7 m slabs an ochre tint.”
