The housing association, l'office 64 de l' habitat has built new company headquarters in Bayonne in southern France. The fact that the building is an ecological example is proudly present for visitors to see. The low entrance building in front of the slender slab has a “green roof” covered in vegetation. This is not only an image-promoting feature as the exterior is also part of a climate control concept which, rather than relying on a battery of technological services, opts for natural methods. Vegetation on the roof acts as insulation and stores rainwater. The space between the glass outer skin and the building façade acts as a temperature buffer for the building within. The solar energy collected there is almost sufficient to heat the offices without other power sources in a mild winter. During a hard winter, two fuel cells are additionally used. The north and south office blocks can be heated independently of one another. In summer, on the other hand, heat build-up in the offices is prevented by the switchable glass slats which let the wind in and is primarily used for night cooling.
The concrete construction's embodied energy and the sun protection, which is individually controllable in each office therefore ensuring a natural, consistent temperature in the building. This means that only the meeting rooms require compact, decentralised cooling systems. The architects have focused on simplicity in their choice of lighting and materials. Good use of daylight, by means of limiting room depth and using glass walls, saves on electric lighting. Materials are joined reversibly, the bare concrete surfaces are only partially clad. This improves the thermal behavior of the building as well as the replacement and recycling options for individual materials.