BARCELONA PROJECT’S S.A.
CARLOS FERRATER, JOSÉ M.CARTAÑÁ
ALBERTO DE SALAS
From 1989-1992, Carlos Ferrater developed a hotel project on the Avenida Diagonal on the southwestern approach to the city of Barcelona. The construction of a huge interior space consisted of a set of planning operations: the first of these was to slide the formwork of the different floors in a play of polygons that would gradually angle and regulate the different surfaces forming the interior facade. This group of changing planes would endow the space with a feeling of dynamism, while controlling its acoustics.
A north-facing plane of metal framework and glass is made rigid, with two brackets absorbing the stresses due to wind by means of a number of horizontal ribs. The steel streamlining constructs the different nodes, accommodating in its pleats the structural framework supporting the glass. This glass wall, plus the openings between the roofs, provides the lobby with northern light, its spatial perception by night being reversed by darkness.
By day the space is projected outwards, accentuating the natural light via the facets and the arrises that make up the regulated interior surface.
By nature the process is reversed, the space closes in on itself, the artificial light emphasizes and retraces the lines, the interior is reflected in the glass, letting the lights of the city to be seen.
The concrete walls made (with sliding formwork), that flank the glass wall, all vertical installations and as function a connecting and circuit-closing device, thus rendering the interrelation of all the service networks possible without intersections.
On the outside, the huge concrete walls lead to a change of scale, helping to situate the building in the landscape. The geometric process, which constructs the geometry of polygonal lines that varies on each level, is obtained by the two irregular polygonal lines which slip between a straight generator and two different arcs of a parabola; The two apexes are never situated on the same vertical and yield intersecting and regulated polygonal surfaces that create the interior facade. Thus, the planes act in a different way with regard to the northern light entering through the great glass wall. If the spectator moves, so does the space and the possibility of different views is almost infinite.
For the construction of the huge interior space of a hotel, on Avenida Diagonal, two 60-meter-high cavity walls were erected, enabling the interior space to be diaphanous.
The regulated surfaces obtained by means of the polygonal play of the decks anchored in both walls and in the vertical circulation core are built with a single formwork that is slightly displaced on different levels keeping with the pre-established geometrical law.