Transformation of a collective housing building in the riverfront of Olabeaga quarter in Bilbao
Located in a small hill next to the estuary of Bilbao, in the riverfront of Olabeaga’s quarter, close to the city centre, 2A Dique street old building was in its origins a two stories farmhouse, that was subsequently converted into a collective household with the addition of three stories more. These very small dwellings were laid out around a tiny compensated staircase, which made its accessibility very difficult. The problem was aggravated with the location of the building in a steep slope, which has a great elevation difference with the street. Besides the housing units lacked insulation or any heating system. All this circumstances, combined with the age of some of the dwellers, make the efficient refurbishment of the building very recommendable. A plan was elaborated and presented to various public institutions in order to obtain aids for the financing of the works.
The project proposes the construction of a new building bay parallel to the north elevation. This element configures a new façade facing the riverfront, and is fundamental as a part of a strategy to solve the problems of the building. It solves the issue of accessibility of the apartments, improves their living conditions by adding new outdoor spaces, serves as bracing and structural reinforcement for the load-bearing walls and timber structure, housing the new solar panels, without adding weight to the existing structure.
A steel structure supports an exterior staircase for vertical communication, located in the central area of the northern façade. This stair unfolds its three flights around a new elevator adapted to current accessibility regulations, and enables to solve the accessibility of the building and its surroundings by means of a single elevator. This condition is critical, given the great height difference between the public street and the access floor of the building.
The proposal involves the construction of a lower ground floor to access a single elevator situated in the current street height. This double entrance lift with parallel operation gives access to upper floors’ housing units from a closed and weather protected space. The central situation of the vertical communication core enables to maintain the views from the apartments, something critical for the owners, but raises the issue of avoiding the intervention to be perceived as a disjointed annex poorly related to the existing building. To avoid this circumstance, two light-weight wooden deck terraces are laid out at both sides of the vertical communication core, enabling a coherent and unitary composition of the façade, and integrating it without shrillness in the volume of the existing building. These terraces, equipped with sliding blade lattices, provide the apartments with a much-needed outdoor space. In a similar way a great roof unifies the ensemble, linking it with the surrounding architecture and giving the building its characteristic image, thanks to the singular geometry of its three-slope roof.
Existing apartments’ access is solved by footbridges that enter the inner building, and are built in a similar manner as the outdoor bay’s structure.
The refurbishment is complemented by an intervention in the building’s thermal envelope, by means of external wall insulation, improving significantly its energetic efficiency and hygro-thermal performance, and solving pathologies related to the age of the building and the absence of previous appropriate restoration interventions. Lateral façades are covered by a new skin of miniwave aluminium sheets with vertical and horizontal joints that help to create a subtle composition similar to stacked sea containers, that takes us back to the industrial past of Bilbao’s estuary. In compositional terms this new skins relates properly to the new front elevation and the intervention, and specially the new building is not perceived as a server element, but rather creates a new façade to the river, that integrates itself into the waterfront with discretion and respect for the building environment of Olabeaga.
This demanding restoration intervention which has been carried out in an inhabited site, help us to show the relevance of public aids for the refurbishment and improvement of the existing buildings, in order to adequate them to current demands and comfort standards. The intervention was selected as finalist in the triennial awards of the Oficial Institute of Basque Architects (COAVN).
Photography: Pedro Pegenaute, behark.