In the heart of Paris’s 17th arrondissement, AR Studio d’Architectures has completed 42UP, a radical extension of École 42 that doubles its capacity on a minimal footprint. The project transforms 3,600 m² into a 9,025 m² vertical campus, accommodating 1,400 workstations within an institution that operates 24/7, with no teachers, no classes, and entirely free of charge.
Architectural strategy: building on the existing
Rather than starting from scratch, the architects preserved the existing building, adding four base volumes and a five-storey steel superstructure rising 18 metres above it. This approach embodies architectural frugality—doing more with less—while respecting the history of the site.
The most striking feature is the suspended steel bridge-building hovering above the existing structure, supported by vertical circulation cores and a 42-metre beam. The third floor, beneath this beam, is left free of columns, creating a spectacular balcony overlooking the city. This volumetric composition combines architectural delicacy with structural boldness.
A perforated white lace
A white perforated metal skin unifies the old and the new, contrasting with the original black façade while creating visual harmony with the neighbouring NOC42 dormitories. The 1.17 x 1.17 metre grid transforms into triangular modules on the superstructure, generating a dynamic relief that changes throughout the day.
This micro-perforated envelope provides essential solar protection in a building housing 1,400 heat-generating computers, while also flooding the interiors with natural light. The façade becomes animated, its transparency shifting according to the weather and time of day.
An urban ecosystem
42UP operates in symbiosis with the NOC42 complex—winner of the Réinventer Paris competition—which provides 700 beds on the other side of the boulevard. Together, they form a true urban campus integrated into the neighbourhood, conceived as a unified vision since 2015.
Optimizing every square metre
The architecture addresses the chronic underuse of educational facilities through spatial efficiency. Large open-plan floors replace compartmentalized classrooms, with peripheral circulation and alcoves behind staircases creating spaces of intimacy. Acoustic absorption is ensured by wood-wool panels and textile finishes, while each floor is distinguished by a strong chromatic identity.
The program includes an amphitheatre, library, gym, recording studios, food area, and relaxation spaces. The accessible rooftop terraces, designed with Atelier MOABI, become elevated gardens—some experimental, others contemplative.
Street art, curated by Nicolas Laugero Lasserre, animates the four main staircases, transforming vertical circulation into an artistic journey. These interventions provide intuitive orientation while enriching the student experience.
