旅游胜地中的绿色公屋 | Ibiza 岛 Platja D’En Bossa 公屋项目

24 public housing units project in Platja d'En Bossa, south of the city of

, in an urban environment mainly dedicated to the tourism industry. The building is located on a square plot of 43x43m, practically flat, situated 5m above sea level, rotated 45 degrees with respect to the cardinal axes.

Based on the tradition of domestic architecture in warm climates - drawing on references such as the classical domus, the Islamic house, or the traditional architecture of the island - the building's placement strategy is based on achieving a certain autonomy with respect to its immediate surroundings by defining an isolated volume, four stories high, that practically exhausts the maximum occupancy and buildability of the plot.

The building is organized around four courtyards that play an essential role in the comfort of the homes and exponentially increase their aspect ratio so that all the rooms and bedrooms have dual orientation.

The structure of the building is resolved with load-bearing walls that form a mesh of spaces with approximately square proportions, establishing a correspondence between the structural and spatial systems of the project. These spaces are organized into two concentric strips - the exterior one with the living rooms, bedrooms, and bathrooms, and the interior one with the kitchens and the four courtyards - that surround the center of gravity of the building, where the stairwell is located, providing access to eight homes per floor, four with one bedroom and four with two.

The eight homes 'embrace' the courtyards in pairs, so that each one relates to this luminous, green, and bioclimatic space through two facades, intensely incorporating it into the experience of inhabiting. The long development of the homes around the courtyards gives rise to transitional spaces, always with good natural lighting and generous dimensions that enable them to be used as versatile spaces, going beyond their mere function as passages. The project complies with a series of indicators in terms of sustainability and energy efficiency, significantly improving the values established by current regulations.

Firstly, non-renewable primary energy consumption is reduced to 10.7 KW/m2/year through passive design strategies such as the definition of a high thermal inertia envelope with thermoclay walls filled with excavation soil, cross ventilation in all rooms, or thermal regulation of the interior of the homes through the roofing of the courtyards with a system of glazed enclosures and operable sunshades that turn them into bioclimatic atriums, i.e., heat accumulators in winter and ventilated shading devices in summer.

These passive strategies make it possible to achieve hygrothermal comfort inside the homes without the need for a centralized heating system, which represents significant savings in energy bills for low-income families who will inhabit the building.

Secondly, CO2 emissions associated with the materials and systems used in the construction of the building are limited to 438.91 kgCO2/m2, i.e., an approximate reduction of 30% compared to a building with identical characteristics built with conventional systems. This objective is achieved through the use of materials such as ceramics manufactured in biomass-fired kilns, the wood of the beams, the structure of the atriums and the carpentry, recycled cotton for facade insulation, or dried seagrass for roof insulation, recovering a construction tradition of local architecture.

Greenery also plays an important role in the project with the aim of mitigating the heat island effect and creating more pleasant living conditions, being located in courtyards, urbanization, roofs, planters, etc. The sustainability of vegetation in Ibiza's arid climate is guaranteed by selecting plant species with low water requirements and reusing rainwater collected on the roof for irrigation, stored in an underground cistern, with the aim of not using network water for this purpose.