Raw Concrete and Steel Anchor Stripped-Back 1960s Apartment in Zagreb
Simple Architecture renovates a modular residential unit by exposing its original industrial structural elements.
1Experimental Residential Origins
The apartment is located in a 1960s residential block in New Zagreb, near the Sava River. The building utilizes the JU61 prefabricated system, characterized by load-bearing reinforced concrete walls and corrugated steel exterior panels. This renovation project focuses on stripping away decades of surface finishes to reveal the raw structural shell.
2Subtractive Design Methodology
Simple Architecture employed a subtractive approach, removing layers from walls, floors, and ceilings to expose the underlying concrete. By stripping the interior, the architects highlighted the building's Brutalist lineage. The raw, unpainted surfaces retain original construction markings and cast textures, serving as a visual record of the building's initial assembly process.
3Structural Intervention Requirements
The original floor plan featured compartmentalized rooms that restricted the living area. To create an open-plan volume, the team merged two rooms into one. Because all interior walls in the JU61 system are load-bearing, the removal necessitated installing structural steel columns and transfer beams, which remain exposed as intentional design elements.
4Industrial Material Palette
The interior design relies on a palette of steel and aluminum to complement the exposed concrete. Built-in furniture and freestanding pieces utilize these metallic materials to maintain an industrial aesthetic. Full-height mirrors and glass panels replace traditional partition doors, effectively reflecting the raw concrete structure while extending the perception of interior space.
5Optimizing Natural Light
The bathroom renovation demonstrates a strategic use of light. By replacing a solid concrete partition with translucent glass, the architects channel daylight from the bedroom into the previously dark core of the apartment. This glass element also serves to backlight an open wardrobe system, enhancing both functionality and the overall spatial atmosphere.
6Flexible Spatial Division
To provide privacy without permanent walls, the design incorporates floor-to-ceiling textile drapery. These operable partitions offer solar modulation and allow the residents to adjust spatial divisions as needed. This soft element provides a necessary contrast to the rigid, rough masonry and concrete cutouts found throughout the apartment's living and bedroom areas.
7Historical Design Context
The apartment features subtle nods to its cultural history, including a 1976/1977 concert season poster from Zagreb. The reading area includes a lounge chair that echoes the building’s original modernist language. These details bridge the gap between the raw, industrial shell and the lived-in, human-centric experience of the modern residential space.
8Renovation Impact and Legacy
This project transforms a standard modular unit into a curated living space that celebrates its structural history. By balancing cold, industrial materials like steel and concrete with soft textiles and light-diffusing glass, the renovation proves that mid-century prefabricated housing can be adapted for contemporary needs while preserving its unique architectural identity.