The youth hostel built on rue de Dunkerque in Paris for St Christopher’s is a project with a dual identity. In this sense, it partakes of the theatrical logic that underpins architecture when its walls become a frontier between two contradictory universes.

Viewed from the exterior, the hostel, constructed in 1926 by the British architect, E. J. Mart, for an American gear manufacturer, is an opulent Parisian building in a mixed style with Art Deco influences. The sculpted friezes on the lintel on the ground floor refer to various aspects of that industry.

Inside the building, the decor is linked to more contemporary activities. The ground floor hosts two bars and provides access to a multi-purpose hall in the basement. We took a “garage rock” approach to these spaces, which are characterized by second‑hand furniture, original uses for technological objects such as coils of electric cable used as tables, motley collections of furniture from various sources, mural panels representing torn posters, and club chairs and architect’s stools. The objects we selected or designed create an ambiance that is at once cosy and informal, suitable for the young people using the establishment.

Because those young people come from all over the world, it was decided that the hostel should have a cosmopolitan character. Every floor represents a European metropolis, with murals featuring iconic scenes. All of these murals are monochromatic, which helps to create a recognizable floor-by-floor colour code. People have permission, and are even encouraged to spray graffiti in the stairwells, giving the impression that these sites are permanently evolving.

Belushi’s, the ground floor bar, is situated in the building’s old courtyard, which has a glass roof. Above the enormous, crescent-shaped bar, a suspended stage dominates the central space, giving the concerts held there an incredible atmosphere, while at the same time providing spectators with a perfect view of the musicians.