Earthy rectangular volumes stretch and grow unhurried from the arid, rural landscape of Alentejo, Portugal, to form Casa Azul, designed by local Portuguese studio, Bak Gordon Arquitectos. Blending perfectly into the sparse and sandy terrain, the holiday home (also christened House in Grândola) displays a bare aesthetic, where the natural soil inspires the earthy dressing of the walls, the tan furniture, and the subtly textured surfaces bathed in ochre tinted lime mortar. The newly completed, elongated dwelling features a charming interior courtyard that channels light into its heart, while two double-height forms sit at either end to create private yet uniquely outdoor lounge spaces, adorned by an intended play of light and shadow, which becomes fundamental to the space.

Built over the course of three years, the residential architecture is planned in a T-shape, a long swimming pool relaxing right next to the low-slung forms' south side. The Lisbon-based architects share that four friends bought four plots of land each and one of them came to them with a wish to build a holiday home with simple, minimal requirements that sat in a chorus with the site. "We realised we had to set a dialogue with the vast, powerful landscape, and match it with the project’s scope and ambitions,” shares Ricardo Bak Gordon, Founder, Bak Gordon Arquitectos.

The plain and linear dwelling is finished in an ochre pigmented lime mortar finish that gives off an understated, mottled texture, while strategically placed, wide geometric windows and openings bring in the sun and provide framed views of the scenery. “The relationship with the landscape should not be too open, especially in Alentejo, where if not controlled, the conditions can become harsh. On the contrary, the idea of framing, as if it were a living painting, became a crucial element,” adds Gordon.

One of the challenges of the contextual design was to reduce the use of materials as much as possible and extend the tone of the exterior walls inside, keeping in mind the changing angles of the sun. The design team also says that "the clash with the landscape was inevitable", so they decided to mitigate the contrast of the "artificial geometry" with the natural landscape with natural-toned soft furnishings and simple, earthy colours that would come alive with the interplay of shadow and light. A conscious and sustainable design choice was also made by employing cork to naturally insulate the house against the extreme heat, a material that “makes the house breathe”. The site's vernacular architecture and setting also informed this material choice, where lime mortar is used extensively to cover buildings in Alentejo.

Two main rooms of the residential design emerge like “turrets at the ends of the building and mark the beginning and the end.” According to Bak Gordon Arquitectos, these are not living rooms or bedrooms but are described as fresco rooms - indoor and outdoor refuges and perfect places to escape the rigorous climate. The idea came about during their initial site visit, inspired by the spaces that frequent the houses further south in Portugal, responding and exposed to the heat – rather than occupying the outside, people live in “transitional spaces” that lie between the interior and exterior – the fresco rooms, which are sheltered yet open, cooler and airier.

The plot drove the placement of these fresco rooms that bookend the house; the one placed at the east end hosts spaces for meals and has a traditional wood-burning oven, and a dining table. The one to the west offers privileged views, where people can watch the sunset and contemplate the landscape of Alentejo in late afternoons.

The site visit also brought forth two other ideas that drove the final residential design – a huge wall on one side of the house that faces south, conceived as a kind of “resonance box” of the landscape and the swimming pool (water tank) at its base that widens at its centre and reflects the scenery, decorated with Alentejo marble slabs. They not only help in protecting the pool wall but also serve as an ornamental element inspired by irrigation tanks which are common in the south of Portugal.

Casa Azul’s 370 sqm space is spread over two floors and organised simply. A long room to host social areas sits between the two fresco rooms while the centre of the open-plan interior design is graced by a small patio surrounded by a curved access corridor that leads to three homey suites, each fitted with small, endearing interior terraces. The fourth suite sits downstairs, accompanied by a garage and service rooms while the spacious living and dining room overlook the shimmering pool outside via large windows.

Bak Gordon Arquitectos’ vernacular-inflected approach to Casa Azul’s design demonstrates simplicity and warmth that can be achieved with minimal interventions. The addition of fresco rooms that come alive without artificial, fuel-based energy elevates the subtle hued house, embracing its Portuguese vernacular elements within earthy details and spaces.