Building the Workers’ Capital

An altogether distinct prefabrication technology was developed in socialist Yugoslavia to facilitate reconstruction after the wreckage of World War II — spurring the production of exceptional, cost-effective mass housing throughout the country and abroad. Known as the IMS Žeželj system, this skeletal prefabrication technology produced apartment blocks altogether different from Soviet panelization. Yugoslav architects used this technology to design varied interior floor plans and assorted exterior facades — socially nuanced and formally versatile housing for the masses.

In New Belgrade — an erstwhile swamp across the Danube River from the capital’s historic center, transformed into the largest construction site in postwar Europe — flexible-plan apartments in socially diverse residential blocks built with IMS Žeželj technology facilitated the elevated quality of life for all citizens inscribed in the Yugoslav constitution. An essential component of the drive to redress Yugoslavia’s housing shortage when it was first developed, even today IMS Žeželj construction remains an impressive case study in low-cost, dignifying public housing.

When New Belgrade was consecrated as the capital of what was then called the Federal People’s Republic of Yugoslavia in 1946, it existed chiefly as an idea in the plans of politicians, architects, and urban planners. Faced with the mass destruction of its urban and rural infrastructure during World War II, Yugoslavia adopted an agenda of rapid modernization, wherein New Belgrade became a symbolic seat of the state’s ambitions to center its urbanization campaign on workers. So many of these latter had arrived in Belgrade from the ravaged countryside in the immediate aftermath of the war that they were forced to live in makeshift temporary structures, pitched on the undeveloped territory where New Belgrade was yet to be built.

IMS Žeželj technology was developed in response to this unprecedented housing crisis. It completely transformed the barren landscape into a functionalist grid of mid- and high-rise apartment blocks to provide quality mass housing amidst a recovering, war-ravaged economy.

Prefabricating Proletarian Domesticity

Branko Žeželj, the structural engineer who conceived the construction system that still bears his name, capitalized on heavy state subsidies for engineering research and the construction industry. In 1957, Žeželj introduced his eponymous prefabrication technology: a prestressed skeletal system of precast columns and slabs. It differed markedly from the extant Soviet prefabrication technology — the Plattenbau — which relied on large-span, precast concrete panels as its basic, load-bearing units of construction.

The IMS Žeželj system consists of standardized post and lintel elements that are assembled vertically and horizontally to produce an internal structure that holds up the building’s weight, giving architects the freedom to experiment with the configuration of interior and exterior walls that have no load-bearing responsibility.

Two- and three-story-high pillars and a square slab, all of which were vertically and horizontally prestressed, create, as Belgrade-based architectural historian Jelica Jovanović explains, a modular structure that can theoretically be multiplied horizontally ad infinitum and vertically up to twenty-six stories.

The system’s iterative skeletal units have no bearing on floor plan and façade design, allowing architects to experiment with open layouts, demountable wall partitions, balconies and enfilades, and ring-shaped circulation around a central kitchen and bathroom core to maximize living space in compact apartments.

Ingeniously simple in its mechanics, the IMS Žeželj system’s prefabricated structural skeleton allowed architects heightened flexibility in designing individualized apartment layouts for residents’ particular needs and differentiated exterior façades. “Taken in sum, these traits signified an identifiable culture of residential design that developed in Belgrade,” explains Jovanović — with an emblematic “Belgrade plan” and a Belgrade school of residential architecture whose members synthesized interests in experimental structural technology with mass housing culture and the social life it cultivated among residents.

“The concept of the Belgrade apartment was a matter of collective authorship,” explains Vladimir Kulić, associate professor at Iowa State University and a curator and historian of architecture in socialist Yugoslavia. A culture of multitudinous mass housing developed under the aegis of open design competitions for New Belgrade’s residential blocks, crowded with young local architects enthralled both by the opportunity to exchange ideas and experiment with the possibilities of self-managed housing.

Communal Luxury for the Masses

Inhabitants, in turn, were met with meticulously planned residential neighborhoods: New Belgrade’s 8,500-person Cerak Vinogradi estate was designed with narrow pedestrian corridors, custom signage throughout the community, ample greenery, and elementary schools in each quadrant of the community. Residential blocks with brick-infill facades and steeply angled roofs underscored the large variety of exterior design solutions devoid of any reference to concrete.

Residents received flexible and transformable apartments — open-plan spaces that could be modified or rearranged to account for changes to family size and number of inhabitants, and to accommodate wide-ranging activities. Spatial flexibility was supposed to enable a culture of self-management.

Citing Milenija Marušić, one of the designers of the residential community, Kulić notes the originality of the architects’ open-plan solutions for small apartments. “They had a very clear awareness of an apartment’s psychological impact,” he explains, “you open a door and you need to see a window at the end, or it feels constrained.”

Long views across multiple areas of the apartment are aligned with windows at either exposure to ensure consistent access to natural light throughout the interior; yet the apartment plans developed for Cerak Vinogradi inventively avoid tight entryways and narrow corridors. In New Belgrade, economical apartments for the working class often came with an airy sense of spaciousness and views, qualities now marketed as the purview of exclusive condos.

There is a potent irony to the fact that, during the peak of construction between the late 1950s and the mid-’80s, New Belgrade’s socialist apartments were designed around qualities now associated with the luxury real estate of transnational capital. Yugoslav apartment blocks were often funded by worker-owned cooperative enterprises that pooled funds among several such organizations to build employee housing at large scale.

New Belgrade blocks famously cultivated socioeconomic diversity among residents — a university professor might live next door to factory workers, for example, such that the formal variety of mass housing blocks reflected the heterogeneity of dwellers in a single such entity. IMS Žeželj technology thus enabled not just mass customization but also alleviation of class differences by affording generous living conditions.

A Blueprint for Transnational Solidarity

Ingenious flexibility remained the defining feature of Yugoslav housing production as it became an export product sold to foreign governments and built abroad.

The system’s variable assembly conditions — its components can be fabricated manually in situ or industrially produced in a factory — and its relatively simple installation process rendered it applicable to a vast array of building conditions, making it particularly appealing to developing countries in the postcolonial world. In total, the system was used to build over 150,000 apartments across Cuba, Angola, the Philippines, as well as Hungary, Italy, and elsewhere in the socialist sphere of influence.

New Belgrade was still very much a construction site when it hosted the inaugural 1961 conference of the Non-Aligned Movement. Yugoslavia was a founding member of this organization, which unified states that refused to align themselves with either the American or Soviet Cold War blocs and fought for a new economic world order that would redistribute the profits from resource extraction more equally. Twenty-five countries, including many newly independent nations, participated in the conference, as did three observer countries and various socialist organizations, labor unions, and national liberation movements as unofficial observers.

Six months prior, the people of Angola had risen up against Portuguese colonial rule; the Angolan War of Independence would last until 1974 — ultimately sparking a revolution in Portugal as well. In 1961, Angola was represented by two revolutionary groups: the People’s Movement for the Liberation of Angola (MPLA), a Marxist guerrilla organization agitating for independence from Portugal, as well as a rival secessionist organization. In his remarks at the inaugural conference in New Belgrade, Yugoslav leader Josip Broz Tito decried Portugal’s violent suppression of liberation movements in Angola — a statement that Yugoslavia followed with fifteen years of material, military, and ideological support for its struggle to decolonize.

Access to high quality housing for working-class Angolans initially took on a central role in the fight for a new economic order. In mid-1976, the government of the newly independent Republic of Angola, now led by the MPLA, approached the Yugoslav Committee for Economic Cooperation with Developing Countries to discuss postwar reconstruction. No doubt, the breadth and depth of Yugoslav experience in rebuilding after World War II was as much an advantage to Angola as was the political sympathies fostered by shared membership in the Non-Aligned Movement. Construction and infrastructure experts were sent the following year from Belgrade to Luanda, the Angolan capital, where Yugoslav consultants found an extant IMS Žeželj factory donated by the Cuban government.

With its building technology already present in Angola, the IMS Institute was selected as the primary collaborator of the Angolan Ministry for Construction and Housing. The Center for Housing thereby received a two-part commission directly from the MPLA to produce a master plan for the Luanda Lixeira housing estate and design its prefabricated apartment blocks.

Design work began on the Luanda Lixeira master plan in 1977, based on a project brief sent by the Angolan government: a settlement for twenty-five thousand residents, accommodating 4,170 families living in four-, six-, and eight-person households. The May 1978 issue of the Center for Housing newsletter, dedicated to the Lixeira project, shows the master plan arranged at an oblique angle to the existing boulevard at the northern border of the settlement’s hundred-hectare site. The plan responds to the site’s irregular topography and the uneven load-bearing capacity of the soil with a rotated functionalist grid of housing blocks.

An elevation shows two-tiered apartment blocks that capitalize on the site’s irregular sloping terrain to accommodate outdoor terraces for each unit in either building – unthinkable in Plattenbau architecture. In turn, the indented apartment plans produced by this response to topography enable cross-ventilation and floor-through layouts with two daylight exposures. The spatial tools to alleviate class difference were supposed to be the same in New Belgrade and Lixeria, where the archetypal Belgrade apartment plan was adapted to the Angolan context, even if Angola’s civil war prevented self-management from emerging.

Socialist Housing in a Globalized Capital

Produced by the Center for Housing to showcase newly developed layouts, a catalog of proposed apartment plans for Luanda Lixeira illustrates the sheer variety of individualized interior solutions facilitated by IMS Žeželj technology well beyond New Belgrade. The booklet includes seventeen distinct floor plans for two-, three-, and four-bedroom apartments, yet the sheer profusion of options also bespeaks the possibility of altering a standard apartment plan, thereby decoupling prefabricated housing from the generic ethos of typification.

Of the twenty-five thousand residents anticipated at Luanda Lixeira, only a few Angolans ultimately moved into the apartments designed by the Yugoslav architects. Two prefabricated apartment buildings, designed as residential architecture for the Luanda Lixeira master plan, were built on a different site in Luanda in 1983. The intensifying Angolan Civil War made any further construction impossible.

It may be that other buildings have since been produced in Angola with structural elements from Luanda’s IMS Žeželj factory, even if the facility itself may no longer exist. Both of Luanda’s original IMS Žeželj apartment buildings stand intact and inhabited, but the larger project’s sociopolitical ambitions — the construction of high-quality, affordable mass housing for Angola’s working class — are unfulfilled. Rather, luxury high-rise apartments crowd the city center and waterfront — Luanda, an oil-boom town and a case study in the exploitative political economy of petro-capitalism, was named the world’s most expensive city in 2017 — reinforcing the grotesque socioeconomic disparities everywhere evident in the urban slums that sprawl beyond the shoreline.

Whatever the perceived inadequacies of any prefabricated housing project, they pale in comparison to the housing iniquities produced by the post-socialist international economic order.