Andina Mellizas Patagónicas

Andina Mellizas Patagónicas is a pair of twin 65 m² houses in the Entre Cerros neighbourhood of San Carlos de Bariloche, Argentina. The two volumes sit between maiténes, ñires and cypresses on the slopes of Cerro Ventana, looking out across Lago Gutiérrez and the runs of Cerro Catedral. Both rest on piles, leaving the natural forest floor undisturbed beneath them. The plans are identical, but the rooms are alternated so that each house adapts to the slope of its own plot, treating the landscape with a light touch.

In plan and section, the form opens out toward the view. The front face tilts outward, producing the entrance overhang and a small extra volume of interior space that projects beyond the footprint. The houses were partially prefabricated in a workshop and trucked to site. To stay coherent with the technique, the whole project is modulated around 1.22 m by 2.44 m OSB rigidising panels, which sped up construction and almost eliminated offcuts. The interior lining uses phenolic plywood cut to 20 cm strips that fall within the same module, saving more time and material on installation.

Opposed windows generate cross ventilation as a passive cooling strategy. A large picture window facing north-west toward the mountains opens the wall and reveals the modular skeleton of the structure. The exterior cladding is black corrugated metal, which helps the houses gain heat passively through the Patagonian winter. For forma, sustainability is read broadly: the responsible use of renewable materials such as timber, efficient construction with very little waste, and simple passive moves like orientation, cross ventilation, exterior colour and good thermal insulation.

Project size 135 m². Site 900 m². Budget USD 120,000. Completed 2017 across two levels.

Architecture by forma, led by Santiago Mussi Tiscornia. Photography by forma.