The city of Bilbao, Spain has a restrictive building code that requires stepped setbacks for all multistory buildings along its main boulevards. Coll Barreu Arquitecto’s response was to assemble a hybrid double skin which not only created a distinctive contemporary face but improved the building’s performance characteristics. The outer glazed skin is composed of framed glass set to a tubular frame. The windows are separated by several inches. Two major benefits arise from the design application: sound levels from the busy boulevard in the heart of the city is significantly reduced, and solar heat gain is curtailed by radiation reduction and a breathable wall system. The separated prismatic face also allows for balconies to wrap the structure without impeding the dynamic facade’s appearance which reflects the ever changing environmental light conditions. Behind the facade a traditional fenestration of double glazing wraps the two street side walls of the facility.
The code required tower hosts meeting spaces in a daylit, two story atrium that opens to a roof deck. The seven stories below contain office space and a subterranean three floor robotic parking lot, providing dense land use.