PREVI Experimental Housing Project, Lima, Peru. Part III
February 3, 2013
Earlier blogs have already looked at 4 submissions from internationally invited architects, this third blog looks briefly at other remaining entries, looking at their proposed designs and main objectives. Let us start by looking at 40 years of growth, starting as ‘immaculate architect deliverd new born babies’, growing out of their original clothes (as intended) and covering their bulging bodies with colourful and attractive garbs to feel good, comfortable and impress others.
Candilis, Josic, Woods (France)
The housing structure is a system of walls defining built and open spaces.
There are two different width of bays, smaller one is 2.7m wide, can be entirely covered forming single or two storey accommodation, the wider bay 4.5 m wide, forming courtyard, patios and living accommodation in different combinations to suit immediate and future needs of occupants. The land can be traded off between adjacent owners to suit their particular needs.
The basic units at the start are all of equal size consisting of two small bays and one large one, and come ready with masonry walls, slabs and concrete beams with water and drainage points and a certain amount of space is enclosed.
The streets serving the dwellings can be orthogonal or diagonal interdisperced with public squares and gardens. Shops can be formed within individual dwellings as happens in existing barriadas.
In early stages of development private cars may be limited to perimeter of the housing area, while service vehicles will use pedestrian ways but these arrangements can be readjusted to suit future car ownership demands.
Charles Correa (India)
Correa said that the project grew from the following four objectives:
(1) Highest possible density commensurate with (2) Individual landownership;
(3) Minimum road and servicing cost; (4) Pedestrian /vehicle separation.
An arrangement of narrow row houses with access at both ends provided the logical answer both to vehicle segregation and minimization of service runs with porches and backyards acting as transition areas between pedestrian and car access and the interior of the houses along diagonal road and footpath routes so as to exploit the prevailing wind for ventilation purposes – aided by airscoopes over the central area of each house – and to achieve optimum orientation with respect to sunlight. Tree planting along pedestrian and service roadways can be employed to modulate sunlight and natural ventilation as well as traffic noise from the central thoroughfare.
The service structure of schools, shops, and church and recreation areas is strung out in a disjointed diagonal moving in the opposite direction to the footpaths and roads. They take the form of the covered shaded areas set in well ventilated clearings and can be easily reached on foot as they can be by vehicle. The shops can be serviced from cul-de-sac service roads. From individual porches one can walk along pedestrian ways until these join the central spine of patios culminating in the central church and shopping area.
There is a single underpass linking both halves of the site across the central area.
The houses themselves are designed in such a way that they can either be built by their future occupants, with the assistance of the authorities as regards prefabricated elements, subsidies, skilled labour etc.: or they can be completed by the authorities themselves and sold to individual families. The former option would allow greater flexibility and, bearing in mind the efforts have been made to minimize the number of constraints that would be necessary under the circumstances.
Narrow plots resulting in narrow frontages, in architects mind ensured that the façade to be ‘controlled’ was very small and set well back into the porch.
The short span housing offered considerable structural flexibility which could be exploited by the occupants. Further flexibility was offered by building the first stage development to be on ground floor, incorporating a front porch, living/dining area, bedroom, central patio, bathroom, kitchen and a small service patio at the rear. This was considered sufficient for a young family with one or two children. The future stages could add first floor bedrooms and bathroom.
Correa’s ‘interlaced’ scheme generated by the saw-tooth configuration of the anti- seismic outer wall is orientated along the axis that is most conducive to natural ventilation. The major changes have been made on the scale of the city block. Individual owners have now aligned their units along the street front.
“Without malleability you can not have cultural expression-
all you can get is a top-down notion of how people should live” C.C.
Esguerra, Saenz, Urdaneta, Samper (Columbia)
Project tries to create neighbourhoods units with high densities/low rise but individual ownership. This approach also reduces combining services and communications. The supervision of open spaces, security of motor cars, play areas is also assured through this community spirit.
Individual plots are square maximising the flexibility of layouts, reducing party walls, enclosing pedestrian routes with easy access to cars.
There are 20 unit designs available depending on locations within layout, service areas and staircases. The following standard structural components using a 50 cm module are extensively used;
- A standard pre-stressed concrete tee beam and accompanying hollow brick infill elements.
- Prefabricated concrete lintels and porch section and perforated bricks.
- A standard open web steel roof joist with steel support columns to support ‘Eternit’ roof sections.
- Standard prefabricated sinks, wcs, washbasins and showers.
- standardised water, gas and electricity installations.
- Metal doors and window frames and terrazzo stair treads.
Earth banks and areas of planting protect the project from the main traffic route.
This scheme avoids using neighbourhood areas as the scheme avoids the formation of hierarchical structures and offers parallel opportunities for all.
Each single unit is placed in close proximity to a sheltered open space to allow free pedestrian movement and play spaces near homes. These paths/private open spaces are connected with the central servicing zones ensuring a steady pedestrian traffic.
All houses are within ten minutes walk from the central rapid-transit route with adjacent parking areas, services and recreation facilities. Construction is intended to be gradual (north-east corner to south-west) to enable progressive occupation without excessive disturbance.
The dwellings are designed to be built in two stages in variety of ways, the first consist of primary structure, building the prefabricated concrete elements placed by a three-ton crane. The secondary structure stage of completion is carried out by tenants themselves by using lighter elements of clay or concrete blocks, lintels, wall panels, partition, windows, woven fibrous screens and textiles, all capable of assembling in number of combinations to suit occupant’s needs.
The structural walls incorporate storage recesses with doors and ventilation to open air, while shaded areas cool ingoing air.
The open nature of plan still provides acoustically quiet areas in the centre of the house, where the private rooms are situated.
J.L.Iniguez De Onzono and A.Vazquez De Castro (Spain)
The site is divided into ten neighbourhoods, each of about 500 dwellings.
A 3 m wide main pedestrian street runs centrally connecting groups of dwellings.
Groups of one-family houses are standard plans around internal and service patios.
Upper floors are planned alongside access alleys. A circular staircase links the two floors.
The structural system of prefabrication provides a series of permanent shuttered elements for poured reinforced concrete (walls, pillar, and beams).
The main structural grid used is 36m x 36m, derived from practical requirements. The structural grid is separate from the internal module making it independent from internal additions and changes.
The plan of dwelling type is based on a functional separation of service and kitchen spaces, general spaces, and sleeping spaces. This offers maximum flexibility to suit future needs of occupiers who will determine the forms themselves.
The boundary walls of all dwellings are built first. The simplest dwelling thus consists of an undivided space, with water and drainage laid on in the service yard, which at the outset will serve as a kitchen. From this starting point the owner fills in and extends his house. Sanitary and Kitchen fittings are fixed using standard components. Services are grouped to avoid long installation runs.
The structural system has shallow concrete foundation pads, a floor slab resting on the ground and concrete columns and beams, supporting a corrugated asbestos roof.
All basic dwellings are single storey, when the upper storey is required; the original roof acts as shuttering for concrete.
There is no traffic within each developed area, apart from service traffic which penetrates on several wider roads. Parking areas in the first stage are mainly reserved for public buildings.
The urban structure formed by the housing is derived from a clustering principle which operates independently of the dwelling type employed. The plot shape does not correspond to the octagonal shape of the houses, so squares, rectangles, rhomboids and free forms could be employed with equal ease. The chief advantage of the hexagonal house with its low perimeter wall is that it discourages further building by the inhabitants in any direction which would result in the loss of external spaces or internal light a frequent development in self-build barriada housing. In this sense the houses are designed so that further free development cannot work against the best interests of the occupants.
The layout is characterized by thick bands of clustered housing separated by a small number of roads placed as far apart as possible. Each band is six plots deep presenting a wall of houses made up of rows of six and two, or five and three dwellings, to the principle avenue, which is itself developed more or less symmetrically so as to achieve a more monumental character. The access footpaths serving the bands of housing have a more informal aspect which clearly differentiates from the main thoroughfares. Climatic considerations affected this layout as traffic – which is insensitive to climate – runs from east to west, whilst the pedestrian footpaths run south-east to north-west or north-east to south-west so as to take advantage of cooling breezes during the hot summer. Protection from a winter winds is achieved by means of the block staggering shown on the plan.
The arrangement of paths described above allows the breeze to penetrate deep into each band of dwellings, a process facilitated by the lateral staggering of the houses. Both house types1 and 2 are designed to take advantage of this air movement by permitting through ventilation to all interior and exterior private spaces. The triangular patios discourage building over in the manner described above, so that the achievement of a genuinely urban character – instead of a suburban – can be realized. All schools and service facilities are accessible along the diagonal pedestrian paths whilst a variety of safe play spaces for children, communal lawns, plazas with fountains and other open spaces are grouped at the ends of the footpaths in full view of all houses for security.
Car parking is provided along the principal avenues and also in certain areas off the footpaths.
In the design of the houses an effort has been made to avoid the appearance of an industrially produced minimum house – which carries with it a stigma not easily overcome by the inhabitants of former barriadas. Instead an effort has been made to build a measure of flexibility into dwellings which can not only interpret traditional and modern living styles but also adjust to different room arrangements corresponding to individual family requirements.
“It would be a grave error if pre-designed and partially pre-constructed urban environments such as this pilot project proposes should counteract the growth and development of the barriada idea and practice, instead of stimulating it through the erection of improved dwelling types, construction systems and overall community planning.” A.v.E.
Prior to taking part in the competition Aldo van Eyck visited Peru where he observed that in local houses women were at the heart of the home, he placed the kitchen in the centre of the floor plan. He also took a more proscriptive approach to how the owners should expand, creating diagonally walled courtyards to discourage people building on top of them. He failed of course. Outside space is not sacred to a family of eight with another generation on the way.
One of my favourite photos from Domus shows this combinaton of sophisticated Danish technology, precision and grace, embellished and enhanced by this proud couple, who met Knud Svensson as they occupied this house they adored from the first day. Architect promised that one day he would come back to build them a first floor extension to match what they liked, but unfortunately that never happened.
Collective/Community External spaces in PREVI
“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.
It is surprising to note how the constant transformation of the housing units distracted architecture reviewers, while the collective spaces attracted hardly any attention. The collective space, immaterial and flowing, is the most determinant and lasting element of the PREVI.” Quote from an excellent dap paper Issue 9 by Marianne Baumgartner on collective spaces. http://www.architecturalpapers.ch/index.php?ID=90
“EL TIMPO CONSTRUYE! TIME BUILDS” by Fernando Garcia-Huidobra, Diego Torres Torriti and Nichlas Tugas Barcelona 2008. A rather difficult book to get hold of, but I understand most of the Domus graphics and details are attributed to this book
Domus April 2011, report by Justin McGuirk.
Julian Salas & Patricia Lucas from openhouse international vol 37 No 1 ‘The validity of PREVI, Forty years on.
Filed in 70s Housing, Architectural Competition, Courtyard Housing, Developing Countries, Housing in 60s, Indigenous Architecture, Informal Urban Housing, Regeneration, Self-Build Housing, Social Housing, Town Planning, Urban Renewal, Vernacular Architecture
Tags: "Candilis Josic and Woods", "German Samper", "Iniguez de Ozono and Vazquez de Castro", "Knud Svensssons", "Marianne Baumgartner", "Oskar Hansen and Svein Hatloy", "Precasting", "Rationalised Masonry", "Toivo Korhonen", 60s Housing, 70s Housing, Aldo van Eyck, Charles Correa, Experimental Housing, High Density Housing, Modern Architecture, Peter Land, PREVI, Rationalised Construction