Unithèque Lausanne

The extension spans four levels, three of which are underground, with a gross floor area of 13,000 square metres. The project uses 10,700 cubic metres of concrete, including 6,500 cubic metres of recycled concrete, 34,000 square metres of wall form­work and 1,500 tonnes of steel. The structure is based on forty exposed concrete roof beams with a 33-metre span, constructed on a general decking of 4,650 square metres with 450 tonnes of shoring towers. The helical staircase and parapets in traditional formwork demonstrate mastery of exposed concrete in its most delicate applications. The technical gallery combines steel framework and curved concrete wall, creating a functional and aesthetic connection with the existing building.