Text description provided by the architects. The lot locates in the crossroad of the two most important streets of the Ensanche (1862) in Bilbao. The restrictive city zoning rules force to repeat the existing building typology, reducing penthousing, chamfering corners and rising a tower. The building groups together vertical communications and general services within a bone, a prism next to the dividing wall that serves to seven open-plan floors for offices. Above these, there are two more level for institutional and representative uses. The meeting room are placed at the top of the building, into the tower. By the contrary, the Auditory and its services rooms are in the cellar. Under all of this level exist three more floors used just for employees parking.
A double facade solves not only zoning rules requirements but also energetic, fire-resistant and acoustic insulation ones. This duplicated plane is not just a wrapper but a volume between Bilbao and the inner space. This element allows to breath the building.
In the other hand, that folded element produces multiple views of the city, and changing its appearance depending on the point of view , the hour and the season. The objective of this element is introduce the mutability, the dynamic spirit of the city.