The new headquarters, with five underground and seven above-ground floors, provide working space for around 4,500 employees. That is a good 70% more than before, on an almost identical gross surface area of 103,500 m2. The building includes high quality equipment and the latest technologies, including solar panels on the roof and seasonal thermal energy storage (STES), optimizing environmental performance and enhancing staff comfort. Drawing on its previous experience, BESIX contributed its expertise to achieve BREEAM 'Excellent' and 'Passive House' sustainability certification for the building.