Remove the later finishes from a 1960s flat in New Zagreb, and the building’s structure stands in plain view. That is the premise of Raw Apartment, a zagreb apartment renovation by Simple Architecture that leaves the concrete and steel visible throughout.
The flat sits in the western part of New Zagreb, near the Sava River. It belongs to an experimental housing project from the 1960s built with the JU61 prefabricated system. In this method, reinforced concrete walls carry the building’s loads and also divide its rooms. Corrugated steel sheet panels clad the exterior.
Stripping the finishes
The architects chose subtraction over addition. The interior renovation removed the accumulated surface layers from walls, floors and ceilings, so the prefabricated concrete now shows its own texture. According to the project description, the goal was to embrace “the beauty of the unfinished.”
Project credits list raw concrete, microcement, aluminium and glass as the main materials. Principal architect Alexander Yonchev led the work with Monica Stoykova on the design team.
exposed concrete defines the living and dining space, with steel and aluminum elements continuing the apartment’s industrial language
Reshaping the plan in this project
The main living zone was once two small, separate rooms. Simple Architecture Studio joined them into one open volume. The result gives the flat a single, more generous space.
Every interior wall in the JU61 system carries structural load. Removing the dividing wall in this apartment renovation therefore required new structural steel columns and transfer beams. The team left these members visible, treating them as a record of the intervention.
the orange poster is a memento of the 1976/1977 concert season, when major classical musical stars came to Zagreb
The flat now contains a combined living and dining area, a kitchen, a bathroom and one bedroom. Each room connects to the others through the open plan, rather than through conventional doors.
Metal, glass and textile
Steel and aluminium make up most of the furniture, both built-in and freestanding. These metals echo the corrugated cladding outside. The palette reads as a direct continuation of the building’s industrial character.
the former two-room layout was opened into a single, generous living space, supported by exposed steel beams and columns
Full-height mirrors and glass panels take the place of standard partition doors. Daylight passes through these surfaces and reaches deeper into the floor plate. In the bathroom, a solid concrete wall facing the bedroom has become translucent glass. Light from the bedroom now enters a narrow, previously dark bathroom. The same glass forms a backdrop that backlights an open wardrobe.
Floor-to-ceiling textile drapery softens the hard concrete and metal. The fabric blocks sun and acts as an adjustable divider. Residents can decide how open or private each space feels at any hour.
mirrored surfaces replace conventional doors, reflecting the raw concrete structure and extending the perception of space
The approach fits a wider interest in exposed interiors. Dezeen’s 2017 roundup of stripped-back homes included Setagaya Flat in Tokyo by Naruse Inokuma Architects, where cement-smeared concrete walls create an undressed look. This Zagreb flat differs in one respect. Its concrete was always the structure, and the renovation simply stopped hiding it.
curtains create flexible divisions between spaces, allowing the apartment to open up or close down as needed
the raw, unpainted concrete surfaces retain original construction markings and cast textures
existing concrete surfaces remain exposed and raw, revealing the original structure and layers of the building
reading area with a lounge chair, echoing the building’s original modernist language
rough masonry and rough concrete cutouts around doorways document the physical layers of the building envelope
the bedroom retains the apartment’s raw materiality, with exposed concrete balanced by soft textile elements
an open wardrobe system is set against translucent glass, which brings natural light deeper into the apartment
the open layout prioritizes cross-ventilation and unhindered light distribution across the living spaces textural contrasts balance cold steel and concrete finishes with woven textile partitions minimalist kitchen joinery incorporates stainless steel countertops and industrial-grade aluminum panels a compact kitchen in steel and aluminum, continuing the apartment’s raw material palette the illuminated glass partition creates depth while visually extending the compact bathroom translucent glass replaces the solid wall between the bathroom and bedroom, bringing natural light into the otherwise dark space floor plan
the open layout prioritizes cross-ventilation and unhindered light distribution across the living spaces textural contrasts balance cold steel and concrete finishes with woven textile partitions minimalist kitchen joinery incorporates stainless steel countertops and industrial-grade aluminum panels a compact kitchen in steel and aluminum, continuing the apartment’s raw material palette the illuminated glass partition creates depth while visually extending the compact bathroom translucent glass replaces the solid wall between the bathroom and bedroom, bringing natural light into the otherwise dark space floor plan
the open layout prioritizes cross-ventilation and unhindered light distribution across the living spaces textural contrasts balance cold steel and concrete finishes with woven textile partitions minimalist kitchen joinery incorporates stainless steel countertops and industrial-grade aluminum panels a compact kitchen in steel and aluminum, continuing the apartment’s raw material palette the illuminated glass partition creates depth while visually extending the compact bathroom translucent glass replaces the solid wall between the bathroom and bedroom, bringing natural light into the otherwise dark space floor plan
the open layout prioritizes cross-ventilation and unhindered light distribution across the living spaces textural contrasts balance cold steel and concrete finishes with woven textile partitions minimalist kitchen joinery incorporates stainless steel countertops and industrial-grade aluminum panels a compact kitchen in steel and aluminum, continuing the apartment’s raw material palette the illuminated glass partition creates depth while visually extending the compact bathroom translucent glass replaces the solid wall between the bathroom and bedroom, bringing natural light into the otherwise dark space floor plan
the open layout prioritizes cross-ventilation and unhindered light distribution across the living spaces textural contrasts balance cold steel and concrete finishes with woven textile partitions minimalist kitchen joinery incorporates stainless steel countertops and industrial-grade aluminum panels a compact kitchen in steel and aluminum, continuing the apartment’s raw material palette the illuminated glass partition creates depth while visually extending the compact bathroom translucent glass replaces the solid wall between the bathroom and bedroom, bringing natural light into the otherwise dark space floor plan
the open layout prioritizes cross-ventilation and unhindered light distribution across the living spaces textural contrasts balance cold steel and concrete finishes with woven textile partitions minimalist kitchen joinery incorporates stainless steel countertops and industrial-grade aluminum panels a compact kitchen in steel and aluminum, continuing the apartment’s raw material palette the illuminated glass partition creates depth while visually extending the compact bathroom translucent glass replaces the solid wall between the bathroom and bedroom, bringing natural light into the otherwise dark space floor plan
the open layout prioritizes cross-ventilation and unhindered light distribution across the living spaces textural contrasts balance cold steel and concrete finishes with woven textile partitions minimalist kitchen joinery incorporates stainless steel countertops and industrial-grade aluminum panels a compact kitchen in steel and aluminum, continuing the apartment’s raw material palette the illuminated glass partition creates depth while visually extending the compact bathroom translucent glass replaces the solid wall between the bathroom and bedroom, bringing natural light into the otherwise dark space floor plan
What is the Raw Apartment renovation in New Zagreb?
Raw Apartment is a renovation of a 1960s flat in New Zagreb by Simple Architecture that removes later finishes so the concrete and steel structure stays visible throughout. The flat belongs to an experimental housing project built with the JU61 prefabricated system.
What is the JU61 prefabricated system used in this building?
In the JU61 system, reinforced concrete walls carry the building’s loads and also divide the rooms. The exterior of the building is clad with corrugated steel sheet panels.
Why did the architects need steel columns when removing a wall in the flat?
Every interior wall in the JU61 system carries structural load, so removing the dividing wall required new structural steel columns and transfer beams. The team left these members visible as a record of the intervention.
What materials are used in the Raw Apartment interior?
Project credits list raw concrete, microcement, aluminium and glass as the main materials. Steel and aluminium make up most of the furniture, and full-height mirrors and glass panels replace standard partition doors.
