FCC Arquitectura Cuts a Three-Car Garage Extension into a Portuguese Hillside

Most garage additions are treated as a chore: a box for cars, tucked out of sight and forgotten. AT House by FCC Arquitectura takes the opposite view. Completed in 2013 in Portugal, the 101 m² project extends an existing house built in the early 21st century. The brief calls for a three-car garage and an additional space above it. The architects take that modest program and use it to reshape how the whole property meets its sloping ground.

What interests us is how little of the result reads as a garage. The addition is cut into the hillside. A short palette of concrete, weathering steel, granite and glass organizes the climb from driveway to terrace. The parked cars become almost incidental. The real subject is the route: stairs held between rusted steel walls, a cantilevered concrete edge that frames the landscape, and a section that steps down the slope with real conviction. It is a useful lesson in how a utilitarian extension can carry architectural ambition without inflating its footprint.

A Garage That Refuses to Look Like One

From the gravel drive, the addition shows up as a faceted concrete volume rather than a row of doors. The angled carport structure, the dark vertical cladding and the corrugated metal panel break the mass into planes. Each plane catches the light differently, so the building looks smaller and more deliberate than its program suggests.

The glass balustrade running along the top edge matters here. It tells you that the roof of the garage is occupied ground, not leftover space. The cars sit below and people sit above. That vertical split lets a single structure solve both parking and outdoor living.

Concrete Edges and a Porthole

The most memorable gesture is the round porthole set into a solid concrete wall. Beside it, a glass corner cantilevers outward. Solid and transparent, punctured and projecting: the pairing gives the elevation a playful edge that saves it from heavy-handed brutalism. The reeds and stone trough in front soften the base and tie the wall back to the garden.

Elsewhere, the projecting canopy and overhanging slab do quieter work. The board-marked concrete keeps the grain of its formwork, and the timber deck that runs along it adds a warmer, walkable surface. The glazing reflects the surrounding trees, so the building's most open faces tend to dissolve into the setting rather than compete with it.

Weathering Steel and the Climb Through the Garden

Here the project earns its keep. Granite steps descend between weathering steel walls toward a concrete-roofed entrance. In the other direction, a concrete stair rises between the same rusted planes toward a framed view of the hillside. The steel acts as retaining structure, planter edge and landscape wall all at once. Its oxidized surface reads as kin to the autumn foliage around it.

The granite-paved terrace beside the low sloped roof completes the sequence. Instead of one big level change, the architects break the slope into a series of compressed passages and open landings. You move between enclosure and view, which makes a short walk feel considered and gives the garden a structure it would otherwise lack.

Inside: Compression and Release

The interior carries the exterior palette indoors without softening it much. A narrow corridor pairs a rough concrete ceiling with a rusted steel wall and a pine floor, ending at a red door. It is a tight, directional space. The splash of color at the end works as a destination as much as a detail.

The stair landing does the opposite. White walls and a skylight framing the treetops open the space up. Through the railing, the wooden floor leads the eye toward the terrace beyond. The contrast between these two rooms tells you the architects are thinking in sequences, managing light and width to pace your movement through a small building.

Plans and Drawings

The plans clarify the arrangement. The ground level holds three parked cars and a stair, and the upper level lays out rooms beside the outline of the existing house. The addition reads as a deliberate attachment rather than a seamless enlargement: you can see where old meets new.

The section is the key drawing. It shows a three-level house cut into the slope, with a zigzag stair, a retaining wall and a butterfly roof. That roof profile and the stepped stair explain the angled planes you see outside. The retaining wall shows how much of the project is really earthwork, an argument with the topography resolved in concrete.

Why This Project Matters

Residential extensions rarely get much architectural attention, especially when the main program is parking. AT House makes the case that these modest commissions deserve the same rigor as a new build. By treating the garage roof as a terrace, the retaining walls as landscape, and the circulation as an experience, FCC Arquitectura gets far more out of 101 m² than the brief demanded.

There is also a material lesson. A restrained set of concrete, weathering steel, granite and timber, used consistently inside and out, lets a small addition hold its own next to an existing house without shouting. For architects working on similar sloped sites, the takeaway is clear: give the brief its due, then design the ground.

AT House by FCC Arquitectura, Portugal. Area: 101 m². Year: 2013. Photography by Bruno Barbosa.

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