Architects: OS3 arkitektura
Location: 20170 Usurbil, Basque Country, Spain
Architects: OS3 arkitektura
Client: City of Usurbil (Gipuzkoa)
- Meeting point for various cultural groups in the municipality: workrooms.
Location and History:
The building is located on Irazu Street 4, in Usurbil, and is the last of a set of buildings that make up the historical city-center, and so is a building with a remarkable background.
This linear addition of buildings separates two large public spaces: Dema plaza (the main plaza of Usurbil) and Askatasuna Plaza, recently built.
The hierarchy of the two plazas is reflected in the composition of the building complex, materializing in two opposing fronts. The front facing Dema Plaza is composed of facades of load-bearing walls, small-sized openings, and finishings in ashlar stone noble; the front facing Askatasuna Plaza shows a more modest facade of wooden frames and larger openings.
Both plazas are connected by two permeable zones with low-growing plant life, but the dialogue between the buildings and the plazas differ significantly. Virtually all main entrances and the best finishings are concentred on the side facing Dema plaza, leaving Askatasuna plaza in the background.
The Potxoenea building was the last on Irazu, before the Church, and was separated from the adjacent building by a narrow, fenced alleyway (1.7 m wide) in disrepair.
This building, owned by the Municipality, although previously used for residential use, had been empty for years and was in poor structural condition.
The Special Plan for the Preservation of the Urban Core required the preservation of the facade facing Dema plaza as well as determined the basic parameters of the rehabilitative intervention.
1.To maximize the quality of the spaces included in the program proposed by the council, as well as to rehabilitatie the existing space, an expansion was added to better the dimensional conditions.
2. To define a unique space that is integrated into its context, creating a dialogue between that which was and that which was rehabilitated.
The limitations of the extension were defined by the context:
1. On one side, the use of the alleway on the groundfloor was proposed, as the adjacent buildings already had windows facing the alleway on the upper floors.
2. For the other side, a longitudinal extension reaching Askatasuna Plaza was proposed with the following limitations:
2.1. 3 m of separation from the adjacent building.
2.2. To maintain the scheme to setback the buildings that make up Irazu street in a way that would maintain the view of the corner (adjacent to Potxoenea) from the main street.
3. Construction of a basement to create more space, taking into account the difficulties of excavating next to a building with no basement.
4. To exhaust the number of cantilevers permitted under the Special Plan: 30 cm cantilevers on 50% of the southern facade.
This extension was proposed so a transitional space would remain between the remaining facade and the cantilevers. Beyond extending the usable space of the building, this distinguished the new volume from the orginal building.
Within the interior intervention, it was decided to minimize the space allocated to the vertical communication core to optimize its efficiency. In this way, the communication elements of the building (the elevator and stairs) stood on the north side of the facade, giving the areas better lighting and views.
To improve the quality of the interior spaces, we tried to enhance the visual/spatial communication between floors and spaces within the same floor, letting natural light reach the maximum surface area possible to give the impression of greater space.
To hilight the alleyway and its continuity, windowed closures that visually unite the plazas and make the access points to the building visible were proposed.
The main entrance was placed in Askatasuna plaza, facing the new plaza for the first time. In addition to improved accessibility, the entrance was given better emphasis. At the same time, a concrete wall was integrated in order to strengthen the foundations of the adjoining building.
The treatment of the new exterior was determined by the following factors:
The small openings of the facade’s bearing wall were maintained, and new openings were made broader in order to attain more efficient natural lighting. Since it is a cultural buiding, we also found it interesting that the interior could be seen from the exterior.
The openings of the northern facade were reduced to preserve the intimacy of the inhabitants of the adjadent building. Therefore, Potxoenea was given another facade to broaden the openings and let the natural light enter the northern zone of the building.
Finally, and contextualizing our intervention, we decided to adopt the logic of solid/hollow of the surrounding buildings. The heavy facade with small openings that faces Dema Plaza, was given a counterpoint in the much lighter facade with greater openings that faces Askatasuna Plaza.
The premise of lightness was achieved through a wooden skin.
Moreover, the distribution of openings (not aligned vertically) reinforced the weightlessness of the new volume.
The western facade (which remained from the original volume), kept its original pitched roof with eaves, while the new extension protruded from the floor to absorb the eaves under the same roof. In this way, the extension emphasizes the difference in the treatment of the rehabilitated and new facades.
The outer shell of wood is tinted black, but the natural finish is left in the entrance of the building . This natural finish extends into the interior of the building and for the length of the alleyway. With this simple device, the entrance is well-defined from the rest of the openings in the facade.