Casa Biaix reconstructs farmhouse along the Aubareda Path
GRAT Studio reconstructs Casa Biaix along the Aubareda Path in Barcelona, integrating traditional Catalan architectural elements with contemporary design. Positioned on a small hill within a pine forest and an olive grove, the structure is in close proximity to one of the city’s oldest oak trees. The design preserves the historical exterior shape of the farmhouse while introducing a new formal and material language inside. It frames views of the regenerating landscape, partially transformed by a recent wildfire. An austere materiality of lime mortar is applied throughout the project, reintroducing a material traditionally used in rural houses. The local limestone, characteristic of the interiors in Catalonia, defines the color palette of the project.
all images by Simone Marcolin
GRAT Studio utilizes traditional lime mortar and local limestone
GRAT Studio’s architectural team organizes the daytime program on the ground floor to enhance visual connections with a landscape that changes throughout the seasons. On the upper floor of Casa Biaix, the rooms are arranged along a diagonal hallway that shapes the distinctive interior geometry. That oblique form is used to optimize service spaces and accommodate an additional room for the family. The adjacent annex becomes a new living space, connected to the main house by a new spiral staircase. The rear facade opens up, making the house completely accessible and exposed to the elements.
Casa Biaix integrates traditional Catalan elements with contemporary design
lime mortar, traditionally used in rural houses, defines the materiality
a new formal and material language is introduced within the interior

a new annex functions as an extension of the main living space
a newly designed spiral staircase connects the annex to the house
the metallic white staircase subtly contrasts the interior’s rustic textures
a diagonal hallway on the upper floor organizes the interior layout
large openings establish strong visual connections with the natural surroundings
interior spaces balance tradition and modern functionality
the project’s color palette is influenced by Catalonia’s characteristic limestone
GRAT Studio emphasizes material continuity with local construction techniques
the oblique geometry optimizes service spaces and incorporates an extra room
Casa Biaix harmonizes past and present through thoughtful design choices

positioned on a hill, the house is surrounded by a pine forest and an olive grove
project info:
name: Casa Biaix
architect: GRAT Studio | @grat.works
location: Aubareda Path, Barcelona, Catalonia, Spain
lead architect: Guillem Elvira
photographer: Simone Marcolin | @simoneemarcolin
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edited by: christina vergopoulou | designboom