The project is located in a residential area on the outskirts of Alella, one of the coastal towns in El Maresme, Spain. The neighbourhood spans along the mountain’s hillside with an eclectic mix of architectural styles, which causes a sense of discord and disharmony around the site. Because of the steep slope and the closeness between houses, the only open view from the site is towards the sea. On the lower ground of the plot, native trees have grown spontaneously and frame the mountainous countryside, which unfolds in a continuation of rolling hills.

The programme is divided into two staggered levels down the hill, preventing the building from standing out over the street. Two entrances are connected through a staircase along the west wall, while on the opposite front, limited openings control visuals of neighbouring houses. In a radically different attitude, the two other facades open entirely to the outdoors.

A wide ceiling-to-floor window in the south-facing facade frames views of the local landscape from the double-height living area and the upper floor. The roof and walls of this facade protrude two meters beyond the limit of the interior space, acting as a passive climate element that shelters the interior from direct sunshine throughout the day in summer. In winter, while openings at both ends of the north-south axis allow cross ventilation, concrete facades absorb heat from incident sunlight during the daytime to release it when the temperature drops.

On the upper level, the two bedrooms connect to a secluded garden facing the mountain. On the opposite side of the rooms, modular wooden partitions can be totally or partially closed, offering different degrees of privacy and regulating air currents. Above this story, the house’s flat roof acts as a large open terrace.The lateral walls and the roof are built with a system of custom-made prefab concrete slabs and panels assembled on-site in only three days of work. This structure allows for the ten-meter-wide uninterrupted floorplan and minimizes the waste of materials.

Inside the house, walls are clad in brick from a local quarry to maximize thermal insulation through a thermal insulation chamber. The sunk terracotta mortar flees from an industrial environment and combines wooden carpentry and non-recessed lights to create a warm atmosphere. The living room is the heart of the house and connects both levels thanks to its double height. Casa Dosmurs explores the charm of combining generous living spaces with austere materiality and an efficient constructive resolution to create a house where different everyday life activities can happen with intimacy while maintaining an open relationship with the landscape.