En Obra Arquitectos Turns Its Back on Pinamar's Streets to Open a Concrete Pavilion to the Pines

Pinamar is a resort town in a planted forest. Pines run right up to the street edge, and every house sits between its neighbors and the trees. In Alamos House, En Obra Arquitectos (led by Luis Cisneros, Rosario Hillebrand and Eugenia Sosa Abad) start from a clear position on that tension. They build a hard edge toward the city so the rest of the 250 m² house can open completely to the landscape.

That idea is common enough. What makes this house worth your time is how literally it is carried out, and how the two halves differ in character. The street side reads as a guarded object of rubble stone and timber. The garden side is barely a building at all: a thin, board-formed concrete roof on slim columns, with glass and curtains below that can be pulled back to almost nothing. The house works as an L, and the hinge between its closed and open arms is where most of the thinking happens.

A Guarded Face to the Street

From the road, the house gives little away. A timber-clad upper volume sits on a rough stone base, and a concrete canopy marks the way in. Pine shadows break up the surfaces, which keeps the mass from looking heavy, but the message is clear: this side is for privacy, not display.

The entry court softens the transition. Broad-leaved plants, gravel and a glazed wall behind timber slats let you glimpse the stair without exposing the living spaces. It works as a filter rather than a front door, and it sets up the sense of release you get once you pass through.

Stone Where It Counts

The dark fieldstone base is the material that ties the house most directly to Pinamar's geography. It shows up where the house needs weight and cover: under the cantilevered bedroom volume and beside the sleeping rooms. The upper box floats over this rough plinth, and the contrast between crisp timber edges and uneven stone is one of the better details in the project.

Seen from a bedroom at dusk, the stone wall stands next to a sliding glass door and a sheer curtain. Even the private rooms get a share of the garden, but they get it on their own terms, framed by mass instead of exposed by a full glass wall.

The Pavilion and the Pool

Turn the corner and the house changes. The single-storey living wing is essentially a pavilion: timber-framed glazing, red-toned posts and a kitchen bar set under a flat concrete roof. A shallow, stone-edged pool with a stepped ledge sits right in front, so the water reads as part of the room's floor rather than an object in the lawn.

We like that the pool is modest. It is low, shallow and planted around with tall grasses, so it does not take over the garden. The pines remain the main event, and the architecture stays a frame for them.

A Roof That Does the Work

The concrete roof slab is the most important element on the garden side. It overhangs widely, cantilevers past its supports at the corners and stays thin at the edge, which lets it read as a plane rather than a lid. Under it, terraces and galleries extend the living areas outward and give real shelter from the coastal sun and rain.

At dusk the effect reverses. The slab disappears into shadow and the glazed wing glows beneath it, a lantern set among tall trunks. It is a simple move, and it carries much of the house's character.

Kitchen at the Center

Inside, the board-formed concrete ceiling is left fully exposed, and its timber grain carries the language of the forest overhead. A single round column stands near the kitchen bar, the kind of structural fact the architects chose to show rather than hide. Oak cabinetry, wooden stools and a linear pendant keep the palette warm against the raw ceiling.

The kitchen is placed where the house is most open, which tells you how the family is expected to live. Cooking and eating happen at the edge of the lawn, with the pool and pines in view, rather than tucked into a back room.

Thresholds Made of Fabric

Curtains do a lot of quiet work here. Sheer white fabric runs along the glazing, so the boundary between inside and terrace can move from hard to soft to gone. When the sliding glass is open and the curtain drawn aside, the covered terrace, the travertine path and the living room become one continuous floor.

The image of a child skateboarding across the terrace at dusk sums up the intent better than any diagram could. The house is built for use. Its durable, low-maintenance materials suit a coastal climate and a family that wants to spend more time outside than in.

The Garden as a Room

The outdoor program extends well past the roof line. A grill cabinet sits under the covered terrace, an L-shaped cast concrete bench wraps a stone-lined fire pit on gravel, and the travertine pool deck faces straight into the pine grove. Each piece uses the same materials as the house, so the garden reads as a continuation of the architecture rather than a later addition.

The fire pit is the furthest point of that logic: a small outdoor room with no walls and no roof, defined only by a bench, a hearth and the trunks around it.

Plans and Drawings

The plans confirm the L. Bedrooms gather in one arm, while a long open living and dining space runs along the other toward the pool. Upstairs, a single bedroom volume sits at one end and the rest of the living wing's roof becomes a large terrace. The axonometric shows how the two flat-roofed arms settle onto sloping ground among the trees.

The sections are the most revealing drawings. Section B-B shows a floor raised on slender supports above the terrain line, with the upper volume cantilevered beyond. The ground is allowed to continue under parts of the house instead of being flattened for it, a sensible choice on a forested coastal plot.

The elevations show the house's two sides most plainly. The west elevation is almost all glass under a thin roof plane, set beside the stone-clad block. The south elevation is the opposite: stone base, ribbon windows and a cantilevered flat roof, with one recessed glazed corner opening toward the garden.

Why This Project Matters

Many coastal houses try to open in every direction and end up exposed on all sides. Alamos House makes a choice and accepts its consequences. It puts the closed elevation toward the street and the open one toward the pines, and it gives each a different material language: stone and timber for protection, concrete and glass for openness. The result is a house with a clear logic you can read from the curb and feel from the kitchen.

It also shows how much a single well-proportioned roof slab can do. With few elements, a thin concrete plane, a handful of columns, curtains and a shallow pool, En Obra Arquitectos create a living space that shifts between room, porch and garden as the day goes on. For architects working on forested sites, the lesson is to let the structure stay quiet so the landscape can lead.

Alamos House by En Obra Arquitectos (Luis Cisneros, Rosario Hillebrand, Eugenia Sosa Abad), Pinamar, Argentina. Area: 250 m². Completed: 2025. Photography: Mariano Imperial.

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