Estudio ABS Builds BENJA House in Argentina Around a Spiral Stair, a Concrete Shell and Walls of Glass

BENJA House is a 270 m² residence in Argentina, completed in 2017 by Estudio ABS under lead architects Nicolas Butler and Sebastian Saal. On paper the programme is familiar: two storeys, a pool, a lawn, a garage and a run of bedrooms upstairs. The architects frame it with a line we find worth taking seriously. They say the house prioritises inhabiting a structure over structuring a way of living.

That phrase is the project's real brief. Estudio ABS claims that hierarchy here lies in materiality and its monumentality, and that a single formal-structural operation resolves everything the house needs. In practice that means a heavy, board-marked concrete body, large planes of glass and steel, and one spiral stair that the rest of the plan turns around. The question is whether a house this restrained in vocabulary can still feel generous to live in. Our answer is mostly yes, with a few honest tensions along the way.

A Glass Box Behind the Water

At dusk the garden elevation reads as a lantern. The concrete roof slab caps a two-storey wall that is almost entirely glazed, and the pool sits square to it, doubling the lit interior in its surface. It is an easy image to produce and a hard one to get right. What makes it work here is the thickness of the slab edge: the roof is visibly a structural plate, not a thin fascia, so the glass below feels held rather than floating.

The rectangular pool is drawn as part of the architecture, aligned with the house rather than placed as a garden object. Lounge chairs and an umbrella are the only clutter. The result is a garden front that behaves like a stage set for the interior, which suits a house whose authors care more about the frame than the furnishings.

Concrete in Plain Daylight

Under an overcast sky the house loses its glow and you see what it actually is: a grey concrete frame, steel water spouts feeding the pool, a cantilevered balcony with a glass balustrade. These are the more useful photographs. They show a building that does not depend on twilight to hold together.

One frame also includes an unfinished brick building beside the site. We like that it was left in. It places BENJA House in a real Argentine context where incomplete construction and finished villas sit side by side, and it makes the house's precision read as a deliberate stance rather than a default.

A Guarded Street Front

The entrance side flips the logic of the garden. Here the white upper volume cantilevers over a dark wall and canopy, and the ground floor withdraws into shadow. The front door is a black double leaf beside a ribbed translucent glass panel, which admits light without offering a view in. Stone steps and planting beds soften the approach without turning it into landscaping for show.

The smartest moment is the glazed door that frames the spiral stair at night. From the street, the one element you are allowed to see is the house's organising device. It is a small gesture that tells you how the plan works before you step inside.

The Weight of the Side Walls

The side elevations are where the claim of monumentality is most literal. The board-marked concrete volume is cut by a slotted opening, and uplighting rakes across the grain of the formwork after dark. Beside it, the upper block sits on a dark stone base, so the house reads in three bands: heavy plinth, pale mass, glazed opening.

The neighbouring house visible across the lawn is a reminder that this is not an isolated object in a field. The closed side walls are doing practical work as well as formal work, handling privacy toward the neighbours while the long faces open to the garden.

One Stair to Organise Everything

If the single formal-structural operation lives anywhere, it is in this stair. A concrete spiral rises through the living area, wrapped in slender vertical steel balusters that read almost like a cage of lines. Set against a raw concrete wall and a black marble floor, it is the one curved element in an otherwise orthogonal house, and the eye goes to it immediately.

The balusters are thin enough to let garden light pass through, so the stair partitions space without closing it. That matters in a 270 m² house, where a heavier stair would have eaten the living room. Here it works as sculpture, circulation and screen at once, which is exactly the economy the architects describe.

Living Rooms That Open to the Lawn

The living room faces floor-to-ceiling glass that opens to the lawn and pool, and the furniture is kept low and neutral so the view and the stair do the talking. Outside, a covered terrace under the concrete slab holds a long timber dining table. Slotted concrete walls flank it, giving the terrace a sense of enclosure without blocking air or light.

The timber table is one of the few warm materials in the palette, and it is placed precisely where people gather. That feels intentional. The house is cool in its surfaces, so warmth arrives through use rather than through finishes.

Marble Rooms for Daily Rituals

The kitchen pairs taupe cabinetry with black veined marble on the backsplash and floor, lit by daylight through a frosted glass wall. It is a darker, richer room than the rest of the house, and the diffused light keeps it from feeling heavy. Upstairs, a white marble bathroom places a freestanding oval tub behind a glass shower screen, with a window onto open fields.

Here we see the limits of the stated philosophy. These rooms are more about finish than structure, and they lean toward a familiar luxury register. They are well executed, but they are where the house stops inhabiting its frame and starts dressing it.

Plans and Drawings

The plans confirm what the photographs suggest. On the ground floor, living, dining and kitchen gather around the curved stair, with the garage pushed to one side. Upstairs, bedrooms and bathrooms circle the same stair and a double-height void, so the spiral becomes the hinge of both levels. It is a compact and legible diagram.

The elevations are more revealing than usual. They show textured render panels, a timber-clad entry and a grey board-formed block pierced by three vertical slots, while the built house reads predominantly as concrete, glass and stone. The plans also label a timber stair where the photographs show marble treads. These shifts between drawing and building suggest a design refined on site, which is common, but they also show how firmly the concrete mass won out as the house's identity.

Why This Project Matters

Plenty of houses claim a single big idea. BENJA House actually commits to one: a concrete frame, generous glass and a spiral stair that organises the plan, the street view and the living room together. The discipline shows most in the parts that could easily have been overdesigned, like the entrance and the side walls, which stay closed, heavy and quiet.

The project is less convincing when it turns to marble-lined interiors, where finish takes over from structure. Even so, it offers a useful lesson for anyone designing a mid-sized family house: pick the one element that can carry circulation, light and identity at once, and let everything else defer to it. Estudio ABS chose a stair, and the house is better for it.

BENJA House by Estudio ABS (lead architects Nicolas Butler and Sebastian Saal), Argentina. Area: 270 m². Completed: 2017. Photography: Alejandro Peral.

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