PREVI Lima 1969
Experimental Housing Project Revisited

The relatively little-known PREVI project is important for several reasons. First of all, it was set in the context of the overall logic of the informal city. The self-constructed city, comprising houses built by their occupants, played a major role at the time, especially in that particular context, and it is still relevant in today’s Third World cities, alongside all the different or regular forms of architecture and urban planning.

The second reason is the process. The PREVI was the result of a rather complex procedure involving 13 international and 13 local architects, various competitions and, finally, the construction of a new neighbourhood comprising fragments designed by different agents, like a patchwork. The process of design and implementation was successfully supervised by Peter Land, who was commissioned by the United Nations. He pieced together a plan of different parts, all of which were connected to the larger scale of the general form. The result was an exciting combination of parts within a whole. The effect is still visible today, and the intervening years and self-construction have added a further layer of interest and value.

The third reason for the importance of the project is the role of the public space as a cohesive moment, like cement that gives unity to the patchwork of the built pieces. These small voids, designed by Aldo van Eyck and built with prefabricated units from a limited palette, still remain and, seen with the emotion of an archaeological gaze, they continue to speak of the power and the possibilities of the architecture.

In 1965, the Peruvian Government and the United Nations invited British architect Peter Land to design a strategy for mass housing as an alternative to the massive informal settlements that were dramatically taking place in Lima during that period. In 1966, informal discussions began with the Peruvian Government about the PREVI (Proyecto experimental de vivienda, Experimental Housing Project), and its initial form consisted of four different pilot projects (1). For the first pilot project (PP1) Peter Land proposed the organization of an international competition to design 1,500 housing units (2) on a deserted 40-hectare site north of Lima’s downtown. Thirteen international architects (3) were invited to take part in the competition, and an open national competition was organized for architects in Peru to obtain the same number of competitors (4). The international and national sections were implemented simultaneously, and the PREVI competition for 26 selected competitors was announced in 1969.

The competition brief was based on a series of experimental principles (5):

1. A neighborhood and design based upon the high-density, low-rise concept, a module and model for future urban expansion.
2. A growing house concept , with integral courtyard.
3. Configurations of housing clusters within the neighborhood master plan.
4. An entirely human-scale pedestrian environment in the neighborhood.
5. Improved and new house-building methods with earthquake resistance.
6. An overall neighborhood landscape plan.

The jury (6) met the same year in Lima and, having chosen the six winning projects (the international groups selected were Kikutake-Kurokawa-Maki, Herbert Ohl and Atelier 5), resolved to start working on the construction of the 26 proposals chosen for their very high quality and progressive design. Due to political and economic circumstances, instead of the 1,500 dwellings initially envisaged, the pilot scheme comprised 500 homes, with Peter Land’s team drawing up a collage of 20 housing units per architect within a Master Plan defined by him.

The PREVI was designed as a platform for the expansion and the gradual adaptation to changing family needs over time. Its evolution and subsequent changes were essentially anticipated in the original design, but 40 years after its construction, the inhabitants have radically transformed the dwellings in programmatic and formal terms. The transformation of the PREVI is the reflection of a dynamic, consolidated, cohesive neighbourhood that is highly relevant today, in the context of the current crisis.

The site of the PREVI international architecture competition was located some kilometres north of the built border of Lima in the 1960s, bounded and crossed by three important expressways. The area forms part of Peru’s long desert strip between the Andes and the South Pacific Ocean: an arid, dusty landscape of bare foothills and sandy dunes in a broad brownish plain, its air tinged grey by humidity.

The competition brief of 1968 was to design a high-density housing scheme comprising 1,500 family units, each enabling the possibility of further growth. Once the winners had been chosen, the project was temporarily halted due to political changes after the fall of Peru’s President Belaúnde, who, as an architect and urban planner, had been a strong supporter of the housing experiment. When the new government finally picked up the project, and the new master plan including 26 different architecture projects was drafted, the experimental aspects and exemplary approach of the PREVI were consolidated. At the same time, while the master plan designed by Peter Land and his international team respected the variety and quality of many of the competition proposals, the focus shifted from overall planning to housing types. Once completed, the PREVI was reduced to a quadrangular built area, a modern, white, mostly one-storey satellite town.

Today, 40 years later, the PREVI forms part of the overcrowded suburb and has been swallowed up by the constantly growing agglomeration of Lima, incorporated into the endless urban fabric of the city.
The modern architectural approach of the PREVI is hardly apparent. It is by no means an architectural monument; visitors do not discover it by chance. Those who are interested may find evidence of it in the use of certain materials or the form of a window. The original architecture has almost disappeared under the floors, loggias, and layers of glass and plaster that were later added, and the in-between spaces are now the only visible element, remaining largely untouched by the constant accumulation of built mass. The conception of the voids by Peter Land’s master plan has survived the growth of the development.

Beyond a range of private open spaces lies a wide variety of open, intimate public spaces. Although freely accessible, they are not frequented by a wider public, since rather than providing infrastructures, the PREVI housing scheme mainly serves local residents. The spaces are all of pedestrian scale. As a result of this intimacy, the voids are of a collective rather than a public nature, and are well kept by the inhabitants themselves. To ensure their privacy, the limits between the private and the collective spaces are clearly distinguished. A similar observation can be made in the urban settlement of the Japanese roji or more contemporary housing projects, such as the Siedlung Halen in Berne.

The definitive reduced arrangement of the PREVI responds in principle to the competition entry of Atelier 5. A main central axis runs through the project, which unfortunately ended up being very limited in size, without the scope or the importance suggested by the original scale of the plan. A series of cul-de-sacs provides the only vehicle access to the PREVI, but cars can be parked in sight, corresponding to the social prestige of the properties.

A smaller-scale network of paths leads to the various housing plots. The centripetal arrangement of these paths is conducive to strolling around. They lead through an attractive succession of spaces created by the different designs of the houses, and their specific entrance situations, breadths, vistas and lighting conditions. The pavement mainly comprises large concrete blocks laid directly on the earth and desert sand. Instead of each building unit having a front garden, occupants who wish to have a garden can easily remove a block of the pavement to create a small bed for plants.

Bound by the walkways, the neighbourhood has many small plazas. These intimate spaces, almost like courtyards, offer small paved squares and bordered gardens. The borders consist of bench-like prefabricated concrete units. Just three types of elements are combined to produce a variety of arrangements: curved semi-circles in plan or section with a circular perforation. The border, more like a wall than a fence, showcases the enclosed green spaces. These leafy gardens emerge like slightly run-down oases in the desert aridity.

A large recreation area is situated in one corner of the PREVI, next to the abandoned factory complex of Montagne. A sandy area accommodates a football pitch and a basketball court. Beyond the football pitch is the playground, framed by prefabricated benches. The playground consists mainly of a family of different objects installed on a flat plot. Slim steel arches held together by slight bridges suggest a fragile tunnel that invites children to climb, hang on or slip through it. Another climbing frame alongside it is a hybrid grid of vertical and horizontal steel bars: frames of cubes stacked one on top of another. Contrasting with these lightweight constructions is a large concrete base, a sloping sunken semi-circle overlooking the pitch. In the middle of it stands a slide, its chute fixed by ties.

Though many years have passed, bearing in mind the premise that Peter Land’s team addressed the influence of each participant throughout the design process, the composition of these elements suggests the contribution of Aldo van Eyck.
This assembly of highly static, geometric abstract objects, their gravity-defying impression of lightness and the sculptured border all recall the playgrounds of post-war Amsterdam designed by Aldo van Eyck for Amsterdam’s Department of Public Works. Van Eyck addressed the issue of interstitial voids and defined space and place, producing interventions that were both numerous and ephemeral. His ambition of creating a space for children that was “more durable than snow” was realized in the desert of Lima.

The PREVI competition established a theoretical framework that revised the functionalist urbanism established by the former CIAM according to new urban principles. Could you define those principles?

The PREVI built project itself defines the new urban principles. It is a more comprehensive take on functionalism, but does not contradict the theoretical framework of CIAM. It abandons some elements, such as the machine aesthetic and high-rise imagery for common sense reasons. The urban principles of PREVI are human scale and a pedestrian orientated environment. It incorporates lessons from vernacular practice, high-density, low-rise planning, integrated small private courtyards, efficient and appropriate new and improved building technologies, expandability and earthquake resistance.

In 1969, some of the most interesting architects from all over the world were invited by you to participate in the international PREVI competition. Could you explain the main reasons for their selection?

I was very familiar with progressive architects and their ideas and projects in the housing and planning field at that time. The competition document sent to all 26 architects was conceived to gather this experience. The final international list considered UN geographic and political representation, as well as experience, talent and available funding. The objective was to have architects with engineers from developing and developed countries in Asia, Europe and South America to focus on the challenging global problem of urban social housing.

The original competition result was moved from the 3 international and national winners, with the participation of 26 teams into a master plan defined by you. What were the reasons for that change, and under which parameters was the master plan defined in relation to the original competition entries?

However, 24 of the 26 proposal were successfully built. Two projects were not built, those of Herbert Ohl from Germany and Takahashi, et al. from Peru, owing to their technical and material complexities, which the Housing Bank would not finance. The parameters of the master plan prepared by me for the 26 designs, instead of six, was influenced by some of the competition ideas and shaped by the need to harmoniously fit together the various geometries of the different clusters. It considered the circulation and form geometry of the clusters in relation with the overall master plan. The compact neighbourhood includes interior pedestrian circulation, access and movement and perimeter vehicular circulation with parking. All the clusters focus on pedestrian access to the school and kindergarten, linked to each other by the central ‘alameda’ and a network of pedestrian streets and small plazas, around the larger landscaped community park, with a planned adjacent community centre for commercial and neighbourhood administrative facilities. All these elements were the components of the master plan proposal.

One of the main issues of PREVI was to allow inhabitants to expand and adjust their houses over time, but beyond what was anticipated and planned, PREVI has been radically transformed by its inhabitants in programmatic and formal terms over the last 40 years. Did the future occupants participate, somehow, in the design process before its construction? And how do you consider the PREVI evolution in relation to your expectations of change over time?

PREVI considered and studied the desires and living patterns of future occupants of the project in the design process. The target was low-income families who qualified for a low interest loan for the purchase of a small, basic first stage, contractor-built house in one of the different clusters. All the international architects were brought to Lima for ten days to study the basic components of the programme: the site, they visited typical low-income families, squatter settlements, urban slums, government housing projects, they met Housing Bank officials, examined materials and practices of the building industry. This programme gave the architects an in-depth view of the problem, as far as time and resources would permit. Later on, pilot houses in the different clusters of the neighbourhood were opened to prospective buyers before purchase.

The evolution and consequent changes in PREVI were essentially as anticipated in the original designs of the houses. They were space expansion and progressive adjustments to more precisely fit family needs over time and in appearance. These changes reflect the different family identities. The expansion of the houses after the construction of the project did not always follow what was anticipated and planned. In some cases, traditional building methods replaced new systems for expansion. However, the general lines of expansion of the houses have been successful because the initial design and construction of the houses was fundamentally sound. The transformation of PREVI reflects a dynamic and thriving neighbourhood of variety, rather than uniformity. Forty years on, the urban texture of PREVI reflects the economic and cultural evolution and progress of low-income families in the neighbourhood, and confirms my own expectations of change over time.

One could say that, after its completion, PREVI crystallized the changes in architectural and urban discourse during the late sixties, establishing a new route for future projects. Why do you think it has been forgotten, somehow, during the last 40 years? Do you know of any similar contemporary experiences?

PREVI was basically completed in 1973. Urban social housing has not been a popular topic for several years. Architecture and schools of architecture became dominated by spectacular and iconic design fashions. Schools have been strongly influenced by this, with diminished interest in social housing or the socio-economic basis for rational design and planning in general. Soon after the completion of the project, I prepared the draft of a book on PREVI, which was supported by a grant from the Graham Foundation in Chicago. After much effort, I was unable to find a publisher at that time who was interested in the subject of social housing and urbanism. However, this negative climate is changing. There is a new and growing interest in PREVI, and my own book−which covers the planning, design, and building−has just received a new publication grant from the Graham Foundation. A global revival of interest in urban social housing is also evident by the publication of ‘Time Builds’ (2008), which is the first book on PREVI and it is stimulating national and international new interest in the project. There have been no other contemporary projects similar or with the scope, size and objectives of PREVI. The famous Weisenhof Siedlung, built in 1927 in Stuttgart, is a smaller housing project, international in scope, with high-density, low-rise development, experimental in design by international architects who were progressive and famous at that time. Like PREVI, it took over thirty years for it to be re-discovered and its importance recognized, but it is not for low-income social housing.

Which do you think is the most important contribution of PREVI to the architecture discipline? In other words, why look again to PREVI after 40 years of its construction?

The reality of collective and experimental action focused on a growing global need for urban social housing is fundamental for political and social stability, and it is not limited to the Third World. If schools of architecture are to embrace these realities and train students to understand, work on and contribute to these very exciting new challenges, the necessary components for this must be practically and realistically incorporated into educational curricula and research to be effective. Such initiatives need to include inspiring young professionals and others with that unique combination of vision, practicality and a strong social conscience.