Block 5B in Nantes: the red/brown brick architecture as a link between the railway and the city

A versatile project gives colour to a new railway station district

In The French city of Nantes, the last fifteen years were marked by important investments for the “Euronantes” project, a new neighbourhood situated in between the historical centre, the central station and the banks of the Loire. Accommodations, offices, hotels, shops, sports and recreational areas : the whole neighbourhood was transformed into a dynamic urban area, where it is great to live, work and relax. One of the most original projects is “îlot 5B”, a group of buildings situated in front of the railway and that helps to demarcate the northside. RAUM Architects’ project is characterised by the nuanced brown/red bricks, rounded façades and window openings with lattice. The project was nominated for the Prix de l’Equerre d’argent of 2021.

Importance of the city

The complex consists of three different volumes: a six-storey, 500-space public car park, a three-storey office building and a partially removed 18-storey residential tower. These different functions are distinctly different in shape and size, but are linked by the specific treatment of the façade. The car parks are characterised by an exoskeleton in on-site coloured concrete and floors made of raw concrete. The residential buildings and the offices of the SNCF network are visually united by brick N10 brick E, which was mainly used as a brick slip. This red-brown brick gives everything a strong and natural aspect thanks to its authentic character. The artisanal manufacturing method of this brick guarantees its natural nuance with a strong identity. Made with the Wasserstrich technique, the NATURE10 brick E integrates perfectly within the existing urban look. To break the massive character, parts of the façade are straight and have repetitive window openings, with decorative window grilles adding an extra touch, just like the traditional Claustra bond. Of course, facing bricks and not brick slips were used for the Claustra masonry.

VETAbric system

Since the building is a tower with a height between 28m and 50m - a building of 4th class according to the French norm - the structure of such a building is of great importance. The choice fell on brick slips in combination with the VETAbric-panel system. Only the VETAbric system can be used under such circumstances, as opposed to glued slips. These panels are 25mm large and weigh between 12 and 14 kg, which makes them lighter than a double brick wall. The panels and corners are all manufactured in the factory, ensuring not only an industrial quality finish, but also an aesthetically perfect façade. Moreover, these panels take less time to install than traditional brickwork.

Heterogeneous complex on a human scale

Block 5B is seen as a catalyst for neighbourhood life. The emphasis is put on the relationship between the user and the environment. This principle is reflected primarily looking at the variety of usage of the buildings. By bringing together different functions, the block of buildings forms a neighbourhood within the neighbourhood, actively contributing to the development of the area.

To reinforce the human scale of this project, the architects have also developed an intelligent route-system for pedestrians. In between the curved corners of the office and parking building, a concrete staircase is integrated, providing access to the different parking levels and to a public rooftop terrace. This terrace not only offers wide views on the railway line and the urban landscape, but also a restaurant and glass greenhouses that invite people to take part in their community.

Comparable case studies

Two impressive hexagonal towers in London with facing bricks NATURE10 Brick E and Brick S

Hoxton Press on the Colville Estate, a housing development in Hackney, in East London was designed by world famous architects David Chipperfield Architects and Karakusevic Carson Architects.