Architecture : Ateliers Jean Nouvel

A technical and aesthetic challenge at the architect’s service

Located in the former Renault factory in Boulogne-Billancourt, and designed by Ateliers Jean Nouvel, the Horizons tower is a building featuring innovative architecture that breaks away from the standard office tower design used so far.

In this project, Jean Nouvel designed the atrium to be grandiose and spectacular in its sheer size and the materials used: to achieve this, he created a contrast between ultra-raw concrete on the walls – sandblasted and almost naked, and a single vertical 250m2 panel covered with a powdery plaster finish of immaculate purity. Two beams of light made of the same material accurately outline the path the sun’s rays take as they illuminate the atrium during the day.

Behind the architect’s exacting aesthetic requirements to achieve such a minimalist effect of raw plaster, there lies a major technical challenge. AC Matière was approached by Ateliers Jean Nouvel to deal with it. A large number of samples and several weeks of testing (texture, application and strength tests) were required, and our workshop was finally selected to take up this twofold aesthetic and technical challenge.

Purity and delicacy 25 metres above the ground

25-metre high scaffolding and a team of 8 people were mobilised for this project. A whole new way of working had to be found that went on almost without interruption so that no breaks would be created in the material and so as to achieve the ultra-minimalist look the architect wanted. The job ended with a waterproof compound being sprayed on by a specialist company to protect the material from damp while preserving its aesthetic qualities.

The panel, as pure and white as plaster, answering back to the ultra-raw concrete walls, creates a total contrast with the stainless steel mirror ceiling designed by Ateliers Jean Nouvel. The natural play of light and water brought to the fore by the sun’s rays reveal the materials in their original purity, and offer a unique experience.