265.000 slates to adorn the roofs of the Cité internationale de la langue française

Under the impetus of President Emmanuel Macron, its restoration campaign was launched in 2020, under the project management of the Center des Monuments Nationaux.

Cupa Pizarras, world leader in natural slate (established in Rennes since 1990) contributed to this by delivering 265.000 slates from its Historic Monument selection.

Between March 2021 and January 2023, 45 roofers mobilized to rehabilitate 3.600 m2 of roofing, as part of a consortium made up of three companies: Balas, expert in heritage renovation (agent and responsible for coordination), accompanied by two local roofing specialist companies, Lelu (Pimprez) and Roquigny (Soissons).

Two years of work to bring a royal castle out of ruins

The restoration of the roof of the Château de Villers-Cotterêts began in December 2020, with the deposit of a steel deck cover which served as a temporary solution. A complete study of the framework was carried out before being able to lay the first slate, in March 2021.

To carry out this monumental project, three perimeters were entrusted to the companies selected for the redesign of the roof:

• the Balas group was in charge of the North, West and South wings (for a total of 120.000 slates),
• Lelu worked on the east wing and Roquigny on the tennis court building (the ancestor sport of today's tennis, prized by François I).

The worksite was supplied by the distributor Asturienne.

For Frédéric Poisson, Project Manager at Balas: “It is a real pride to have contributed to restoring this castle steeped in history where the coat of arms of François I is omnipresent. It was a very technical project since it was also necessary to take into account the three circular turrets, the two square turrets and the large glass roof which covers the tennis court. We thus managed several sites in parallel, in collaboration with the masons and the carpenters. It is rare to intervene on a project of this scale for a complete overhaul and we are delighted to have been able to put Balas' know-how in terms of heritage at the service of its rebirth. »

A Cupa Pizarras Historic Monument selection dedicated to heritage gems

For Villers-Cotterêts, Olivier Weets, chief architect of historical monuments, chose a selection of slates which also adorn the Palais de la Bourse in Bordeaux, the castle of Azay-le-Rideau or even that of Fontainebleau.

Cut by hand, the Historic Monument selection is extracted from the best areas of the Spanish Cupa Pizarras quarries. It is particularly appreciated for its dark gray tint, its reliability and its longevity.

To respect the character of the building, the roofers carried out a so-called “blurred” installation, installing slates of different sizes: mainly 30x20 cm, but also 30x18, and 30x16.

For Stéphane Renard, Commercial Director of Cupa Pizarras France: “We are very happy to have participated in this presidential project. France is our largest market in the world, we export 80.000 tonnes of shale there each year, and the Château de Villers-Cotterêts is a new exceptional reference for Cupa Pizarras. Beyond its traditional character, slate extends the life of historic buildings thanks to its durability: its lifespan is estimated at around a hundred years. It is also the roofing material with the lowest carbon footprint throughout its life cycle, which makes it possible to reconcile history and the future, with regard to the environmental challenges that we face today. »