BVAU designs translucent bioclimatic skin for French social-security agency HQ
Paris firm BVAU has built an extension to the headquarters of a French social security agency, featuring a glass facade that opens and closes automatically in response to the climate (+ slideshow).
![Office building by BVAU](https://static.dezeen.com/uploads/2015/11/Office-Building_Social-Security_Grand-Paris-France_BVAU_dezeen_936_4.jpg)
The building extends the existing headquarters of Caisse des Français de l'Etranger, which provides social security for French citizens abroad, and it is located in a suburb to the south of Paris.
![Office building by BVAU](https://static.dezeen.com/uploads/2015/11/Office-Building_Social-Security_Grand-Paris-France_BVAU_dezeen_936_0.jpg)
BVAU co-founders Jérôme Villemard and Eric Bartolo designed the bioclimatic skin to naturally light and ventilate the building, but also to give it a "welcoming and pleasant" appearance.
![Office building by BVAU](https://static.dezeen.com/uploads/2015/11/Office-Building_Social-Security_Grand-Paris-France_BVAU_dezeen_936_10.jpg)
Thermal sensors control panels in the facade, allowing them to open or close depending on the weather.
Other recent examples of this innovation include a palaeontology centre in Barcelona, a glazed sports centre in Paris a house with perforated shutters in Linz.
![Office building by BVAU](https://static.dezeen.com/uploads/2015/11/Office-Building_Social-Security_Grand-Paris-France_BVAU_dezeen_936_9.jpg)
"We decided to experiment how architecture could solve its thermic control," Villemard told Dezeen.
"Ecology is a very good pretext to rethink what makes architecture fundamental and useful," he added. "The skin is a fundamental architectural element of the building, creating an interior climate, and establishing the interface between inside and outside."
![Office building by BVAU](https://static.dezeen.com/uploads/2015/11/Office-Building_Social-Security_Grand-Paris-France_BVAU_dezeen_936_5.jpg)
Inside, office floors are arranged around a large central atrium, which helps to draw light into the building. Some are concealed by ribbed wooden panelling, while others feature floor-to-ceiling windows.
![Office building by BVAU](https://static.dezeen.com/uploads/2015/11/Office-Building_Social-Security_Grand-Paris-France_BVAU_dezeen_936_11.jpg)
Elevated footbridges connect both offices and boardrooms to the organisation's existing three-storey building.
"The client was very precise about quantities: how many people working, how many rooms to include, how many meeting rooms, square metres and budget," said Villemard.
![Office building by BVAU](https://static.dezeen.com/uploads/2015/11/Office-Building_Social-Security_Grand-Paris-France_BVAU_dezeen_936_12.jpg)
"On top of that very precise demand, we decided to work specifically on the qualities in order to organise the programme into two kinds of spaces: collective spaces, transparent with each other and individuals working spaces with more intimacy," he added.
![Office building by BVAU](https://static.dezeen.com/uploads/2015/11/Office-Building_Social-Security_Grand-Paris-France_BVAU_dezeen_936_2.jpg)
A concrete car park and gravelled plant beds form the base of the building, intended to create a "surprising and minimalist landscape".
![Office building by BVAU](https://static.dezeen.com/uploads/2015/11/Office-Building_Social-Security_Grand-Paris-France_BVAU_dezeen_936_8.jpg)
"Components of the projects are dealt with equal attention: an office building and an outdoor car park, forming a facility with the existing building," explained the architect.
Photography is by Clément Guillaume.
Project credits:
Project management: BVAU (Bartolo Villemard Architecture Urbanisme)
Client: Caisse des Français de l’Étranger
Engineers: 3A Architectes Associés, TN + Paysagistes, RFR, RFR element, Avel acous- tique, BETOM (TCE)
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![Office building by BVAU](https://static.dezeen.com/uploads/2015/11/Office-Building_Social-Security_Grand-Paris-France_BVAU_dezeen_2_.gif)
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![Office building by BVAU](https://static.dezeen.com/uploads/2015/11/Office-Building_Social-Security_Grand-Paris-France_BVAU_dezeen_4_1.gif)