Dva Arhitekta Stacks Concrete, Brick, and Timber into a Biodynamic Winery in Rural Croatia

Forty kilometers southwest of Zagreb, in a village of 300 people called Donja Reka, the Tomac family has been making wine for over 70 years. Their property has grown organically across that span, accumulating houses and outbuildings into a loose rural ensemble. When vineyard capacity demanded a new production facility, Dva Arhitekta didn't design a standalone icon. They designed a building that reads as three distinct structures stacked on top of one another, each built from the material most suited to its purpose: raw reinforced concrete below grade, thermobrick at ground level, and laminated timber rising into a thatched straw roof.

What makes this 679 square meter winery genuinely interesting is the rigor of its vertical logic. The architects treat each storey not just as a different program but as a different tectonic system, with its own construction language and environmental rationale. The concrete basement is massive and cool, ideal for aging champagne. The brick ground floor references a century-old stable the architects noticed on their first site visit. The timber attic dries crops. And on top of it all, a roof garden grows the herbs used for the family's biodynamic preparations. Every material is left exposed, intended to weather. Nothing is decorative.

A Barn That Belongs to Its Landscape

From a distance, the winery registers as a large agricultural building, which is precisely the point. The thatched hip roof and timber lattice walls sit comfortably among the surrounding vineyards, forests, and open meadows. Dva Arhitekta positioned the new structure to form a courtyard with the existing farm buildings, creating a green plaza at the center of the ensemble rather than competing with it.

The aerial views reveal how deliberately the building avoids imposing artificial boundaries on the landscape. No fences, no manicured hedges. The concrete apron transitions directly into mown grass, which gives way to vineyard rows and tree lines. The winery is conceived as part of the ecosystem it occupies, not a container dropped onto it.

Brick as Finished Surface

One of the boldest decisions here is using Porotherm thermobrick as the final facade material. This product was never intended to be left exposed; it's a structural infill block typically hidden behind plaster or cladding. Dva Arhitekta treated it as a finished product, developing a stacking plan for every individual brick, the way a stonemason would lay ashlar. Special attention went to corner joints and openings, where the pattern logic had to resolve cleanly.

The result is a wall surface with real visual depth and texture. Shadows catch differently across the grid of perforations. Different bond patterns meet at column edges, creating subtle shifts in rhythm. It's an honest expression of a building material that also happens to provide thermal insulation within its own structure, eliminating the need for additional cladding systems.

Timber Canopy and the Harvest Threshold

The laminated timber structure sits on top of the brick box "like a hat," as the architects describe it, and its overhanging eaves create covered outdoor spaces at ground level. These sheltered zones aren't incidental; they serve a specific programmatic function during harvest season, when grapes need to be processed under cover but in open air.

The diagonal bracing of the timber frame is both structural and atmospheric. At dusk, the colonnade of angled columns and deep beams creates a procession of shadows along the brick walls. The covered walkway feels like a cloister, transitioning visitors from the open landscape into the interior program. It's a threshold condition that most wineries ignore entirely.

The Attic and the Roof Garden

Climb above the ground floor and the building shifts register completely. The attic level is pure timber: exposed beams, plywood panels, slatted railings, cross-bracing everywhere. Its primary function is drying agricultural crops, a utilitarian program that the architecture serves without dressing up. The corridors are narrow and functional, lit by gaps in the timber lattice facade.

Higher still, a rooftop terrace hosts planting beds for herbs used in biodynamic preparations. The dark decking and stone retaining walls frame views of the meadow and forest beyond. Surrounded by the thatched straw roof, this garden occupies the most symbolically charged position in the building: the place where architecture literally feeds back into the agricultural process it was built to support.

Underground: Concrete and the Archive

The basement is where the building's tectonic ambition becomes most legible. An L-shaped plan in raw reinforced concrete connects the new cellar to the existing one, bridging the family's winemaking past and present. The coffered ceiling is the underside of the ground floor's structural skeleton, left exposed as both finish and structure. Linear lighting runs between the beams, casting even illumination across rows of barrels and storage cages.

The most compelling space underground is the archive, a circular room lined with timber shelving and wrapped in a cylindrical screen. Here, champagne bottles age in baskets, and the geometry shifts from the orthogonal logic above to something more ritualistic. The curve creates a sense of interiority that the rest of the basement's corridors deliberately avoid.

Interior Craft and Material Honesty

Throughout the interior, the principle of material honesty holds. The timber staircase casts diagonal shadows across brick tile floors. The tasting room features a slatted timber ceiling with linear lighting and a long pale wood table, a space that feels generous without being luxurious. Narrow corridors alternate vertical timber slats with warm recessed lighting between concrete columns, layering materials in sequence as you move through the building.

Nothing is clad. Nothing is hidden. The reinforced concrete skeleton, visible only from the interior, is covered on the exterior by the brick walls, but inside it reads clearly as the structural frame. This decision lets the building communicate its construction logic to anyone who walks through it, which seems appropriate for a family that has been building and rebuilding on this site for seven decades.

Barrel Room and Ground Floor Program

The ground floor is organized as a simple rectangular box containing large wine barrels arranged against ceramic tile walls. The timber beams of the structure above are visible overhead, reinforcing the vertical material sequence. This is the production heart of the building, where grapes become wine, and the architecture stays out of the way.

From the exterior, the timber lattice facade with its diamond-shaped openings filters light and air into the upper levels while giving the building its most distinctive visual identity. At sunset, the lattice glows. It's the image that will circulate most, but it's worth remembering that this graphic surface is doing real work: ventilating the drying attic and protecting the interior from direct solar gain.

Plans and Drawings

The section drawings reveal the full extent of the vertical strategy. The pitched roof structure is set into sloping terrain, with the basement level entirely below grade. A double-height interior space at the tiled wall demonstrates how the ground floor and attic relate to each other spatially. The architectural model, with its repetitive diagonal bracing and translucent roof panels, confirms that the lattice pattern isn't applied ornament but the genuine structural rhythm of the timber frame.

Why This Project Matters

Winery architecture has become one of the most reliably overwrought building types of the 21st century. Too many examples prioritize spectacle over process, treating the winemaking program as a backdrop for tasting rooms and event spaces. Tomac Winery reverses this hierarchy. The tasting room exists, but it's one node in a vertical sequence that runs from underground champagne aging to rooftop herb cultivation. Every level serves a specific agricultural function, and every material choice follows from that function.

Dva Arhitekta's achievement here is proving that sustainability in architecture doesn't require technological complexity. A straw roof, honest brickwork, timber framing, and a concrete cellar, these are elementary components assembled with clarity and discipline. The building will age. The brick will weather, the timber will grey, and the thatched roof will soften. That's the plan. In a region where families have been making wine for centuries, designing a building that improves with time is the most respectful thing an architect can do.

Tomac Winery by Dva Arhitekta (design team: Tomislav Ćurković, Marko Galić, Barbara Vuković). Donja Reka, Jastrebarsko, Croatia. 679 m². Completed 2022. Photographs by Sandro Lendler.

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