Álvaro Siza Vieira completed a riverside Art Gallery in northern Portugal, which has been elevated above the ground to protect against eventual flooding. The Nadir Afonso Foundation, located on the banks of the Tâmega river in the city of Chaves in Portugal, has been built using white concrete walls with carefully positioned openings to provide natural light.
The main floor of the Nadir Afonso Foundation — named after the geometric abstractionist painter — is positioned on a concrete platform at a height of 3.5 meters. This platform is supported by walls perpendicular to the river, and is accessed by means of a slight ramp. The program is divided in three primary sectors: the atrium, which includes the reception, a library, and a 100-seat auditorium; exhibition spaces, which are subdivided into three longitudinal wings; and staff and administration areas, contained within the northeast part of the building.
The main exhibition room, which can be asymmetrically subdivided in two, includes a continuous clerestory window, allowing natural light. The exhibition room in the southeast wing is illuminated by a horizontal opening over the river. The interior finishes consist in wood floors, plasterboard on the walls and ceilings and white marble on the water zones.
The interior window frames are made of wood and stainless steel, while the exterior ones are made of wood and aluminum..