The geometry of the building is of a very simple nature. It is a rectangular prism at the top of the landscaped slope facing Les Vinyes square. On top of this prism there is another rectangular prism of great height which is a light well facing West.

The structure of the box comprises nine porticoes with three pillars each, one on each of the opposing façades, and the central pillar coinciding with the interior partition. This way, the building offers a totally undisturbed open plan in its wider strip, where the library as such is placed, whereas the narrower strip concentrates all the services, storage rooms, conference room and all other parts of the brief which require a smaller enclosed area.