Constructed in 2006, the Casa de Invitados, in Chile’s Licancheu region, is seriously reductivist design. Designed by the Santiago-based AATA Arquitectos, the project was low-cost and the brief straightforward. ‘The client wanted a small cabin for guests,’ says AATA’s Sebastián Cerda Pé, ‘so we thought of it as an element that stands on the ground without interacting with it.’
A two-storey 5.4m cube, the Casa de Invitados is also low-energy and low-tech, using mud-coated straw bales as insulation, clad with transparent polycarbonate panels. The polycarbonate 
is paired with corrugated zinc panels, creating 
a functionalist, almost agricultural appearance. The architects describe the green roof as a ‘fifth facade’, as it’s visible from the approach of the hilly site. ‘It’s covered with grass, which prevents the wind taking away the heat,’ explains Cerda Pé. ‘The windows are located to allow as much sunlight as possible during winter, and a cross-flow of air to ventilate it during the summer.’ Inside, white walls maximise the natural light. The double-height volume leaves space for a sleeping deck, accessed by a simple, chunky timber ladder. Outside, an expansive deck offers calm views over the surrounding hills.