Transforming a historic château, inside and out, into the new regional home of contemporary art in France.

The chateau of Domaine de Rentilly, Bussy-Saint-Martin (77) is the location of the new Fonds regional d’art contemporain (FRAC) in the Ile-de-France. The building was completely transformed from a dilapidated chateau to a new contemporary art gallery with a stunning and unique mirror stainless steel facade conceived by French artist Xavier Veilhan. The completely mirrored building reflects the English-style park on the one side, and the French-style garden on the other. We carried out the structural and facade engineering for the building.

To transform it into the gallery space, we first stripped out all walls and columns from the interior to create wide and open spaces. The retained facade, the new three levels of exhibition space and panoramic roof terrace was then re-supported by the introduction of a series of new 13m wide, full height flat portal frames recessed into the perimeter walls to maximise the internal gallery space. New moving walls have been installed internally to allow flexible hanging of artwork.

As the brick arch vaulted basement was retained, cores had to be drilled through the brick structure below to allow new piled foundations to be created and for the steel frames to drop down through. A new lift structure was installed internally. The new public entrance to the building was created to be at the basement level through the 16th century foundations.

To ensure a perfect mirrored finish on the exterior of the building, getting the right thickness of steel was key to eliminate distortions and imperfections. To do this, together with the architect, the team researched different materials and suppliers and carried out tests and developed prototypes for the new facade. The profile of the cladding follows that of the chateau underneath.

A new lightweight, entrance bridge uses slim depth steel profiles to appear to float over the dry moat which runs around the perimeter of the chateau.