Extension of the Palacio Euskalduna convention and exhibition center, at the foot of the existing building, has been built taking advantage of the slope of the land within 9 months since the award of the contract.

It is a unique space under single roofing, defined by a surrounding irregular façade. The cover features metallic panels with a peaks-and-valleys shaped outline, placed in changing directions, getting a heterogeneous picture without a defined geometry of the group.

The cover is made with modular panels of 12.00 m x 2.20 m. To produce them in the described shape, a first welded waterproof outer skin of stainless steel sheet of 1.5 mm thickness is manufactured at workshop, and then an inner core of rigid structural insulation like PET is glued onto the metallic skin. Over the insulation a fireproof polyester resin sheet reinforced with fiberglass is laminated being the visible finish at the inside of the building. The panel joints have tongue and groove edges to guarantee the airtightness and water tightness of the roof.

The façade is solved with a conventional stick curtain wall made of steel with a continuous rubber sealing system, overlapped and glued with EPDM. The double-glazed units have serigraphs in two faces of the glass to give depth to the façade and the drawings simulate the crests and valleys of the roof as the characteristic picture of the building.