The expansion of the European Union has necessitated the expansion of the European Parliament building. The new office wings, D4 and D5, provide the extra space required. The former Luxemburg Station, a listed monument, is flanked by the new wings and incorporated into the existing site. The entire site will be connected by an elevated walkway suspended over the Luxemburgplein.

The new wings each contain 8 levels and were built according to the principles of non-progressive collapse – the failure of one part of the structure will not trigger the collapse of the remaining structure. D4 houses office space, parking and a polyvalent room. D5 houses a restaurant and bar, technical rooms, 5 conference rooms with interpreter cabins, and audio-visual services. The AV rooms contain, amongst other things, a television studio, and several radio station studios. The 2 wings have adjoining underground levels which reach all the way to the Luxemburg Station. By reinforcing the foundations, the monument was united to form one whole site, without sustaining any damage.

The elevated circular walkway has a diameter of 60 meters, weighs 280 metric tons, and rests upon 8 columns. The facades and floors work with the beams and lattice work to carry the load through to the columns. The bridge is covered with glass panels and woven metal sheets, offering those travelling over the walkways a measure of privacy as well as protection from the sun’s rays.