Bauen Arranges a Cruciform Residence Like a Windmill Across a Paraguayan Hillside

The name translates to something like "Shadow Rehearsal," and that is precisely the game being played here. Bauen, led by architect Aldo Cristaldo Kegler, organized a 390 square meter house in San Bernardino, Paraguay, as four linear wings radiating from a central glazed pavilion, a plan that reads from the air like the blades of a large windmill pinned to a grassy slope above a lake. The cruciform footprint is not arbitrary geometry. It produces four distinct courtyard zones, each catching light and casting shadow differently as the sun tracks overhead. The house rehearses its own darkness.

What makes Ensayo Umbra genuinely interesting is the tension between its material heaviness and its spatial porosity. Stone retaining walls anchor the building to the terrain like geological formations, while corrugated metal volumes hover overhead on exposed steel frames, filtering daylight into shifting patterns across timber decks and glass floors. The house does not sit on the landscape so much as it grows through it: trees pierce decks, grassed berms fold into approach paths, and the pool occupies the exact crossing point where the four wings converge. It is a building that treats its site as a collaborator rather than a canvas.

Arrival Through the Landscape

You do not arrive at this house so much as you ascend into it. The entry sequence passes between stone retaining walls and micro hills of sculpted grass, threading beneath eucalyptus branches and alongside timber-clad volumes that reveal themselves incrementally. The approach is deliberately compressed: low walls, dense planting, narrow sightlines. Only once you pass through does the building open up into its full cruciform extent.

The stone base walls do double duty as landscape infrastructure and architectural enclosure. They hold back the slope, define terraced levels, and establish a tectonic register of permanence against which the lighter steel and metal elements read as almost temporary. Stepping stones ascend alongside these walls, reinforcing the idea that the house is something you discover through movement rather than comprehend in a single view.

The Cruciform Logic

From the air, the organizational logic becomes unmistakable. Four wings extend outward from a central steel and glass tower, their white roof planes slicing through the tree canopy like compass needles. The courtyards between them are not leftover space. They are calibrated outdoor rooms, each with a different relationship to sun, wind, and the distant lake. One holds the pool, another opens to the broader lawn, and the rest frame views of mature trees that predate the building.

Bauen's decision to organize the house radially rather than linearly means that no room is more than one turn from the exterior. The wings remain narrow enough that cross-ventilation is possible in every space, a critical strategy in Paraguay's subtropical climate. The plan is generous at 390 square meters, but it never feels bulky because the cruciform disperses mass across the site.

Steel Frames and Corrugated Skins

Look up inside Ensayo Umbra and you see the building's skeleton: diagonal steel cross-bracing, exposed trusses, corrugated metal ceiling louvers that filter light into ruled lines. Bauen chose not to conceal the structure, and the decision pays dividends. The steel framing registers the forces at play honestly, its diagonals working against wind and gravity in ways you can trace with your eye. Against the dusk sky, these elements become silhouettes, dark geometric figures against diffuse color.

The corrugated metal cladding is not merely economical. Its ridged profile catches light at oblique angles and creates a moiré effect when layered, lending the facade a visual depth that flat panels would not achieve. Paired with the exposed steel, it establishes an industrial material palette that the timber decks and stone walls then soften. The hierarchy is clear: structure in steel, enclosure in metal and glass, ground in stone, inhabitation on timber.

Living Between Interior and Exterior

The principal living spaces sit behind full-height glazing that effectively dissolves the wall between inside and out. Exposed steel trusses span overhead, a concrete fireplace anchors the room, and beyond the glass, the pool terrace extends the floor plane outward. The interior planting and the trees visible through the glazing create a continuity that makes it difficult to locate the exact boundary of the house. That ambiguity is deliberate.

A glazed floor panel in one corridor allows you to look down through the structure to the level below, a vertical transparency that complements the horizontal openness. The effect compounds: you are always aware of where you are in the section of the building, not just in its plan. Bauen treats the house as a three-dimensional diagram of relationships between earth, enclosure, and sky.

The Deck, the Pool, and the Trees

Some of the most convincing moments in Ensayo Umbra happen on the timber decks. A concrete kitchen island sits under a corrugated metal balcony while a preserved tree grows straight through the floor, its trunk a living column. Nearby, a concrete fireplace anchors an outdoor room open to the sky. These are not token gestures toward landscape integration. They represent a genuine willingness to let the site's existing vegetation dictate spatial decisions.

The lap pool occupies the central courtyard, serving as the crossing point where the four wings of the house meet. At golden hour, the pool becomes a reflective plane that throws light back up onto the corrugated metal soffits, doubling the shadow play that gives the house its name. A figure standing on the poolside deck at sunset, pendant lights glowing overhead, occupies a space that is simultaneously domestic and theatrical.

Dusk and the Shadow Play

Ensayo Umbra is photographed at dusk for good reason. The building's louvered facades and corrugated screens produce their richest effects in low-angle light, when shadows stretch long and the interior glow begins to compete with the fading sky. The vertical louvered facade becomes a lantern, its slats alternating between illuminated strips and dark voids. The elevated steel volume above its stone retaining wall reads as a dark mass hovering over the ground, connected to the earth only by the thinnest structural means.

Levinas wrote about reality and its shadow as inseparable doubles, and the house takes the philosopher at his word. At dusk, every solid element generates an equally present void. The corrugated ceiling creates striped patterns on the deck. The steel cross-bracing throws intersecting lines across the glass. The pool reflects the sky downward. To inhabit this house at sunset is to occupy a space where the material and the immaterial negotiate in real time.

Plans and Drawings

The ground floor plan confirms the windmill analogy: four linear wings extend from a central glazed pavilion, their walls radiating outward like blades from a shared axis. The pool sits precisely at the intersection. Trees are drawn in their existing positions, several of them within or immediately adjacent to the floor plate, evidence that the plan was negotiated around existing vegetation rather than imposed on a cleared site.

The roof plan reveals the steel truss structure that spans the central crossing, its geometry legible as a distinct element hovering above the four wings. The section drawing is perhaps the most telling: it shows the building stepping down the slope, with a central elevated volume rising above a glazed enclosure, establishing a vertical hierarchy from the stone base through the timber living level to the steel and metal crown. The sloping site is not flattened but amplified, each level of the house engaging a different stratum of the terrain.

Why This Project Matters

Ensayo Umbra matters because it demonstrates that a house can be organizationally bold without being formally extravagant. The cruciform plan is a simple, even ancient, diagram. What Bauen does with it is anything but simple. By rotating the wings to engage specific views, threading trees through decks, and layering materials from heavy to light as you move upward through the section, the firm creates a house that feels rooted and open at the same time. In a region where residential architecture often defaults to either colonial pastiche or generic modernism, this house proposes a third path grounded in landscape, material, and geometry.

The philosophical conceit of shadow as a double of reality could easily have remained decorative, a name and nothing more. Instead, Bauen embedded it in the building's material logic: louvered screens, corrugated profiles, glazed floors, reflective pools. Every surface in this house produces shadows that are as spatially present as the surfaces themselves. The result is a residence that changes character across the day, rewarding sustained attention. Not many 390 square meter houses in the Paraguayan hinterland can claim that.

Ensayo Umbra, designed by Bauen (lead architect Aldo Cristaldo Kegler, with team members Dalila Morel, Jacqueline Colina, Saúl Acosta, and Dina Agüero). San Bernardino, Paraguay. 390 m². Completed 2022. Photography by Darío Mereles.

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