العربيةEarth House / Lara Fuster Prieto
Text description provided by the architects. The Earth House is located in a municipality of just over a hundred inhabitants, a paradigmatic place of the rural exodus of the 60s and 70s and of the empty or emptied Spain. The project is a direct result of the program’s needs and its context: a housing workshop in Tierra de Campos, a treeless plain in the Castilian-Leonese plateau, with an extreme and dry climate.
The traditional popular architecture of the region is based on adobe or raw earth bricks, as earth and straw are practically the only local raw materials. These are supplemented by baked mud (tiles, bricks, tiles, etc.) and wood. All of them make up a characteristic landscape, where pigeon houses are one of the most representative constructions. Construction with adobe bricks has minimal environmental impact; the raw material can be found on the land, it does not require cooking for its production, and it can be reintegrated directly into nature after its deconstruction.
The permanently inhabited house had to offer great climatic comfort, generating the least environmental impact. For this reason, adobe bricks from a nearby adobe factory were chosen as the main construction material. The rest of the elements, without being locally produced, maintain the criterion of having a low environmental impact. Although adobe bricks are strongly linked to the identity and culture of the area, their use in new construction projects today is practically nonexistent. In this proposal, traditional materials are adapted to current construction processes and ways of living.
The result is a single volume completely integrated into the landscape that houses an open and constructively sincere interior. It is a rectangular building organized in four parallel bays from east to west. The north facade, aligned with the street, has asymmetric openings of smaller dimensions, giving it a similar appearance to traditional constructions in the area. The distribution of the interior space is oriented towards the south facade, where it presents larger openings that act as solar collectors during the winter and are protected by wooden blinds and a pergola with deciduous vines during the summer.
For the construction of load-bearing walls, adobes measuring 33x15x10cm have been used, manufactured less than 40 kilometers from the site. On these walls, and with the support of three central laminated wood pillars, laminated wood beams that form inclined portals supporting the roof slab are placed. The gable roof is composed of a wooden sandwich panel cork insulation and reused curved clay tiles, whose patina allows for the complete integration of the volume into the urban landscape of the town. The walls are covered with eight-centimeter cork panels as insulation on their exterior face, like an External Thermal Insulation Composite System (ETICS). Although trullado is the traditional plaster in the area made of clay mixed with straw, in this case, the house has been plastered with a mixture of lime mortar and straw for greater durability.
Unlike cement, lime has properties of breathability and absorbency similar to earth, providing ideal resistance for exterior walls. All the carpentry is made of wood, with roll-up shutters located on the openings of the south facade as sun protectors. In the interior distribution, essential compartments have been made through lightweight partitions, composed of a framework made of visible wooden slats, insulation of recycled cotton blanket, and Medium Density (MD) wood boards. The upper third replaces the wood boards with polycarbonate sheets to lighten the interior perspective and make the most of natural light throughout the space.
The adobe remains visible on its interior face, except for the rooms equipped with wet facilities, where the exterior load-bearing walls are covered with the same system as the partitions and fully tiled. The A-rated house does not require cooling systems, the inertia of the materials used and the proper insulation of the entire envelope have allowed it to maintain constant temperatures between 22 and 24°C during the last summer period, in which temperatures of up to 40.5°C have been recorded.
In winter, due to the extreme climatic conditions of the area, the house requires heating. For this purpose, underfloor heating has been installed, whose heating system resembles the glorias, the traditional heating system of the area, an underground chimney system that heats the house from the ground. In summary, the project of the earth house is based on the premise of designing a new construction project with the least possible environmental impact and is completely linked to the culture of its context through the selection of materials.
