The striking glass exterior of this Health Department building in Bilbao, Spain isn't just a pretty face(ade). Coll-Barreau Arquitectos conceptualized the folded facade in response to the city's restrictive building code that requires stepped setbacks for all multistory buildings along its main streets. The result was this eye-catching hybrid double skin that boosts the structure's energy efficiency in addition to making it stand out on the boulevard.
The folded facade consists of two layers. The outer one is a glazed skin made up of framed glass set in a tubular frame while the inner layer is the building’s windows. There are two major benefits to the design: noise from the busy boulevard is noticeably reduced and solar heat gain is decreased via radiation reduction and a breathable wall system.
In addition to the increased energy efficiency afforded by the double skin, the building holds meetings in a daylit, two story atrium that opens to a roof deck. To promote denser land use, the seven stories below roof contain office space and a subterranean three floor robotic parking lot.