House X stands firm amidst the vast Mediterranean landscape as an ancient fortress of the Castilian plateau, dominating the surrounding natural and built environments. Located in the nature preserve Serranía de Cuenca, near the town of Valdemorillo in Madrid, Spain, the residential architecture emerges from the rocky landscape with a strong desire to inhabit the land with identity and permanence. The residence is designed by the 2012-established Spanish architecture studio Bojaus Arquitectura—founded in Madrid by architects Ignacio Senra and Elisa Sequeros—a multidisciplinary practice that crafts built environments addressing individual and collective well-being. Reinstating the intent and design approach behind the assertive building, the architects go as far as calling its nature “invasive, almost parasitic” in the press release.

To integrate the built environment into the gently sloped rocky landscape, the Spanish architects take inspiration from the houses of Monsanto, a town in Portugal known for its giant boulders that are an inseparable part of its local architecture. Local vegetation—such as holm oaks and kermes oaks— and a grand, centuries-old oak tree emerge amidst the granite boulders to inform the position and orientation of the building. The residential design also takes cues from Spanish architect José Antonio Coderch’s Ugalde House, built in the early 1950s in a small village in Barcelona. Much like Coderch’s design, the dominant cuboidal forms and openings of House X form complex and intimate relationships with one another, along with the natural landscape, while framing the views. One can find many similarities between the architectural elements of the two buildings, such as low ceilings, dynamic semi-open areas and large glass windows that overlook the sloped, rocky landscape.

As the name suggests, the residential layout follows the geometry of the letter X, forming sharp, visually dominating edges and vertices on the outside while establishing a clear hierarchy of common and private spaces within. The residence separates the spaces through subtle differences in levels, featuring bedrooms and bathrooms in the north while accommodating common areas and semi-open spaces in the south. While the large glass windows bring in natural light and ventilation, the exposed concrete walls add visual interest to the otherwise simple cuboidal geometry of the residential architecture.

Locally sourced aggregates contribute to the composition of the concrete ceilings and walls, which are built to endure harsh weather and last generations. The half-metre thick walls are equipped with insulation on either side, ensuring thermal comfort within the spaces. The bathrooms and the outdoors feature limestone flooring, while the interior floors and furnishings are made of oak and walnut wood, respectively. Crafted from lasting materials with sustainability in mind, the private residence is built to last generations, rooted in the site as much as the elements of the natural landscape.

The architects incorporate the learnings from the case studies—the Ugalde House and the houses amidst Monsanto’s rocky terrain—into their conceptual and contextual design: a testament to their research-driven and holistic design approach. Adhering to strict geometry and simple, minimalist forms, House X prioritises materiality and complex relationships among the interior spaces. Going beyond a sustainable design approach, the architects consider the comfort and living experience of the residents, ensuring minimal maintenance and adaptability while designing the residence.

Project Details

Name: House X
Location: Valdemorillo, Spain
Architects: Bojaus Arquitectura
Built-up area: 220 sq m
Gross floor area: 190 sq m
Site area: 2,000 sq m
Year of Completion: 2024