Standing 107 metres tall with 33 storeys, the Astro Tower is the fifth tallest building in Brussels and the tallest passive building in Belgium. The Astro Tower’s offices, measuring a spacious 35,000 m² and dating back to 1974, have been redesigned and optimised. The façade was given a brand-new look in blue mirror glass. Three additional storeys were built atop the tower to house the technical rooms. There is a five-storey car park underneath the building. At the end of 2016, 1,200 employees moved into the building.