Casa LA near Barcelona by Alventosa Morell

The photos only hint at it: The detached house built by Alventosa Morell in Llinars del Vallès, north-east of Barcelona, is located in a rather densely populated residential area. Although the site was unshaded to the south and east, the design had to take account of the limited privacy. With a simple design strategy, the architects were able to provide protection and comfort for the residents while reducing energy consumption.

Unplastered brick walls and extensive pergolas make up the inconspicuous exterior of the building. © Adrià Goula

A central fireplace and four square brick volumes form the basic structure of the house and its supporting framework. These contain the bedrooms and bathrooms. Between them, the space can flow freely, without partitions, to the four terraces that surround the building in all directions. A uniform ceramic tile floor emphasises the continuity between inside and outside. The pine roof structure continues over the terraces, thinned out to form a pergola. The architects also used the same bricks for the house's load-bearing walls. Inside the four closed volumes, the roof structure changes: steel beams and flat ceramic vaults form a traditional Catalan ceiling.

The private rooms are located at the four corners of the building. Between them is a single, undivided open space. © Adrià Goula

The architects used mainly passive methods to reduce the house's energy requirements to 16 kWh/m²/year. Contributing factors include controlled daylighting through large openings, the thermal inertia of the walls and ceramic floor, cross-ventilation and a highly insulated building envelope. Ultimately, this means that the house does not require active cooling. In the colder months, the fireplace and four radiators connected to an air-to-air heat pump provide sufficient heat. To further reduce the building's carbon footprint, natural materials were used extensively, including certified wood for the roof and window frames, cellulose insulation in the walls and ceilings, and ceramics fired with biomass instead of natural gas.