The interior of the prism is structured around a longitudinal circulation spine, flooded with natural light, perforated and permeable, rising up to the roof and operating as a singular spatial continuum. It becomes a large shared interior room—an unavoidable passage where encounters naturally occur. This space connects all residents with one another and with the roof above, which in turn functions as a collective infrastructure: a provider of energy, physical activity, leisure, food production, workspaces, and care.
The roof—the fifth façade of the Hexaprisma—is conceived as a microcity that complements and extends the domestic realm. It integrates photovoltaic fields, vegetated surfaces, individual urban gardens, solariums, a continuous jogging track, gym facilities, coworking areas, laundries, rentable kitchens (both open and enclosed), dining spaces, and a wide range of environments for interaction. These programs form a topological ecosystem of shared functions. Each activity adopts a specific geometry—coworking spaces as rectangles, laundries as capsules, kitchens as half-moons, gardens as cubes—so that architecture itself becomes a catalyst for social exchange, allowing people to inhabit the roof through the pretexts of encounter.
Valladolid, an historic city set within the Castilian plateau and the capital of Castilla y León, is characterized by an extreme continental climate, with annual temperature variations reaching up to 50°C. The site reflects this condition: a north-facing slope with undulating topography and a 27-meter difference between its highest and lowest points, located in Parquesol, to the west of the city, near significant urban facilities.
The building takes the form of a six-sided prism that hovers above the terrain. Anchored on its eastern edge, it gradually lifts as the land descends, minimizing earthworks and avoiding retaining structures. This strategy preserves the existing landscape—its tree clusters and pedestrian paths—while allowing the ground to flow beneath the building. The resulting shaded undercroft becomes an extension of the public realm: a continuous, undulating space for play, movement, cycling, and shelter, activating communal life and reinforcing the continuity of the natural environment.
In section, the Hexaprisma operates as a solar machine, its performance enhanced by the sixth façade. The building breathes vertically through its central spine, enabling controlled natural stack ventilation. All dwellings benefit from north–south cross-ventilation—the most efficient passive cooling strategy throughout the year. The building harnesses solar energy to generate electricity, sustain rooftop agriculture, and maintain vegetated surfaces that improve thermal performance. During summer, pressure differentials across the prism’s faces induce continuous airflow around its envelope, cooling it naturally, efficiently, and without emissions.
Each dwelling functions as a micro-scale solar device within the larger system. A terrace-box captures and distributes light and air, while adjustable louvers on the opposite façade regulate cross-ventilation across the three primary spaces of the unit. The 215 bathrooms are conceived as compact, standardized elements suitable for prefabrication, ensuring construction quality and efficiency. The internal layout allows for both fluid connectivity and complete independence: sliding partitions and dual circulation systems enable the two bedrooms to operate either as part of a shared dwelling or as autonomous micro-apartments, each with its own bathroom, dressing area, and terrace access. The central band of the dwelling—terrace, living areas, kitchen, and entrance—becomes the social core.
Ultimately, the same dynamic unfolds at every scale: within the dwelling, across the building, and in its relationship with the city. It is the productive tension between individuality and community, between personal identity and collective life. The built environment should reflect and celebrate this richness—grounded in choice, respect, and the shared experience of living together.
