To have the tallest building in the world in your project portfolio is something special. The Burj Khalifa is undoubtedly one of the most recognisable architectural monuments in the world. Upon visiting the tower one must pass through one of three entrance pavilions, constructed by Waagner Biro Steel and Glass, through to the elevators to reach the upper floors. It is at this point that one can begin to take in the extraordinary nature of this building from the inside, which is almost a match for its striking exterior, with sophisticated technology meeting the highest standards of quality. In technical terms: the massive roof structure is supported by ten columns inside the building with a height of 20 metre in the hotel and residential area, and 25 metres in the office reception area. These columns are situated 3.4 metres apart on a concentric axis which runs around the cylindrical exterior wall. A heavy girder connects the tops of the columns supporting the roof rafters, which in turn cantilever out, extending up to 3.4 metres beyond the perimeter of the building. The glass façade is a double-glazed cylindrical wall, with a 1.50 metre cavity between each layer, all of which is supported by a complex system of intertwined vertical cables and horizontal tension rods and struts.