Le Havre, World Heritage Site

The southern façade of the I.S.A.I. (Buildings Without Individual Attribution).

The I.S.A.I. (Buildings Without Individual Attribution)

The I.S.A.I. are the equivalent of I.C.E. (Immeubles Collectifs d’Etat, State Collective Housing). The I.S.A.I. are private co-owned buildings, built and financed by the State before being handed over to their owners in exchange for their war damages. They belong to the first buildings erected during the Reconstruction period.

The principle behind the I.S.A.I. was set up in 1944. With these I.S.A.I., entirely pre-financed by the French State (to be deducted from future war damages), the French Administration built housing buildings for the first time. Decided on 8th September 1945, the building of the I.S.A.I. in Le Havre was entrusted to the care of Auguste Perret in February 1946. In March, he chose his main assistant-chief architects who, in April 1946, started on a large number of preliminary studies. Altogether, 14 architects of the Perret Reconstruction Studio for the town of Le Havre (all Parisian architects) were chosen by Perret for the whole scheme, divided in several operations by the French State. Veritable matrix of the reconstruction, this project proved fundamental in determining a plan for the city centre to rebuild. The choices of the structural module, volumes and overall site plans were extended to the rest of the reconstruction.

Directives and deciding on the plans.

The directives from the Ministry of the Reconstruction imposed surfaces for each type of flat. The Minister for Reconstruction and Urbanism had decided the I.S.A.I. would only contain flats. But pressure from the Rue de Paris Committee resulted in shops on the ground floor being accepted; moreover theoretical priority was given to owners who had lost a property on Rue de Paris; granting them accomodation on their pre-war site.

The two hectare site (streets included), is situated on the southern side of Town Hall Square. In sketches made by José Imbert and André Hermant, the side overlooking the square is made of continuous rows of high monumental buildings or of large tall separate blocks linked at their base.

In August 1947, the first walls of the I.S.A.I. arose. In June 1948, application for a new building permit was made for four groups of buildings. The V37, with 90 flats, was the first completed block. In the end, the density of population was 900 inhabitants per hectare.

On 27th June 1949, the High Committee for Hygiene of the Ministry of Public Health considered stopping construction of sixteen city centre blocks, even though excavating had already started, when it was found that toilet cubicles and bathrooms would be aired by ventilation shafts, not windows.

Building the I.S.A.I. was entirely pre-financed by the French State, money to be given backthe war victimsout of the eventual war damages attribute to war victims; that of the lateral extensions to the I.S.A.I. was financed by  a syndicated reconstruction association (of owners) using war damages. These extensions were designed by architects of the Perret Studio together with local architects.

Throughout the whole of the reconstructed city centre of Le Havre, high rise buildings are used to add rhythm to the urban landscape and break the monotony induced by buildings all of the same height. On Town hall Square,  the necessity for an orderly and varied frame led to alternate high and low volumes, placed according to the orientation and general aesthetics of the site as a whole. Above a 4, 90 metre high ground floor, the general volume chosen for the city allowed a maximum of five extra floors. But because of the size of the population needing to be re-housed, and in order to grant the flats a maximum of air and sunlight (André Hermant, who started studies of exposition to sunlight as early as February 1946, invented an instrument to calculate the amount of sunlight on a scale model of flats) the architects had to decide on adding higher buildings. The I.S.A.I. Housing Scheme is therefore disposed thus: behind a row of three storey buildings and linked to them by porticos, six ten storey buildings are positioned in a regular, symmetrical fashion on both sides of the axis of Rue de Paris and parallel to it. Only the top part of those six high buildings can be seen from Town Hall Square. Inside, the square blocks are shaped as largely open, sunny courtyards protected from the winds.

Articulating the volumes of the blocks bordering the I.S.A.I. was studied in order to create a backdrop to Town Hall Square as a whole, within the city’s urban landscape. Here is Pierre Dalloz’s description: “Town Hall Square will be one of the largest in France. The I.S.A.I which line it have the bearing, calm and assurance of a classical piece. The problem of their back façades was closely linked to that of the architectural composition around Commerce Dock and Gambetta Square. A choice was definitely approved by the Minister on 3rd August. The heart of the composition is held by a small, voluntarily off centre, square, whose empty space will allow, from one side to discover the I.S.A.I. and from the other, an equally flattering viewpoint, the future theatre. Set at a right angle from the three storey buildings with a view over Gambetta Square and Rue de Paris, this small square will take part in the sequencing of the I.S.A.I. from the row of five storey buildings on the opposite side, it will become part of a kind of ample greek geometrical design, placed around the theatre, Gambetta Square and Commerce Dock. The two schemes of Town Hall Square and Gambetta Square oppose one another in their arrangement around this small square, offering to the view, in harmonious and picturesque contrast, their dissimilar compositions.”

The various architects who took part in this vast building project produced a collective work using the architectural tenets of the Reconstruction Studio, promoting the strict use of a technical and architectural language defined by Auguste Perret himself. The apparent lines of the structures acquire new importance in defining the sequencing of buildings. Their composition is studied in both a refined and calculated manner, branding the urban landscape with a perspective order of a classical type. The visible constructive structure of the buildings is magnified by the use of bush-hammered concrete. Porticos, built on a uniform square module, are filled with a secondary structure of windows, rising from floor to ceiling and all on a uniform model. For the apparent reinforced concrete, the forms are wooden ones, trimmed and very neat. Between the posts and the window frames, the in-fill panels are prefabricated concrete slabs with agglomerates of natural colour; their dimensions vary to create patterns but never exceed 70cm. The low buildings hold balconies on the first and last floors, whereas high buildings have full length running balconies on the fourth and seventh floors. Rounded reinforce concrete columns add rhythm to the ground-floor. The facing panels inside the buildings are bush-hammered and lined with chiseled edges.

The roofs are terraced because, according to Perret himself, “a terrace protects from the rain as well as a roof” and “ a square top floor is less expensive than a roof”.

In the ten storey buildings lifts were added. Garages are in the basements, accessible by a ramp. There are also laundry rooms and as many cellars as there are flats. On the ground floors, near every staircase are situated stores for bicycles and push-chairs, a boiler room, two service stores and the porter’s lodge.

The ground floor shops come with a high ceiling, allowing a mezzanine to be put in by the owner.

Purety of Structural Classicism

“Standardization, first”, was Perret’s watchword. Building the I.S.A.I. led to experiments later used on the rest of the reconstruction project. The study for the I.S.A.I. led to determine the general structural module used overall. The thickness of the buildings was fixed at 12 to 13 metres, thus reducing the length of façades, always an expensive element. This equals two modules of 6 to 6, 50 metres, a very acceptable span for reinforced concrete. Perret’s final choice was a 6, 24 m module, which could be divided by two or three and whose multiples and submultiples agreed with the dimensions of surfaces imposed by the M.R.U. (Ministry of Reconstruction and Urbanism).

Therefore, the low buildings of the I.S.A.I. are six modules wide and two deep. Each span is made up of 12  modules of 0,52 m (a 6,24 m side square) and the posts are spaced the width of one module. On this site, norms were determined that would allow industrialized construction with prefabrication of constructive elements and interior fittings. These experiments proved useful examples for other constructions of lesser import, as the reconstruction of this part of the city was based on the same structural module. Thanks to this standardization, the tools developped while building the I.S.A.I. were used on other constructions built following the same methods.

Reinforced concrete foundations are done either with piles, soleplates or foundation concrete slabs. The supervibrated reinforced concrete structure (Portland cement, river sand and fine gravel) is made of posts and beams and triple thickness in-fill panels of cinder or brick debris blocks, with a plaster tile allowing space for two layers of air. The floors (slabs and ribs) are made of steel formwork.

The window bay frames, made in advance, are of molded concrete, without any finish. As for the 3500 identical windows, ready-to-build frames were machine-made.

Interior fittings are semi-standardized. Positive results for prefabrication showed for ceilings, partitions and wooden floorings but showed negative for plasterwork. Despite many experiments, prefabrication proved impossible: the plasterer still had to do his job on site.

Relative sound proofing of floorings is obtained by a layer of sand laid on the concrete slab and flooring backing strips are laid on a layer of asphalt; partitions and frames do not sit directly onto the concrete slab; windows are double-glazed.

Terraced roofs are insulated by two layers of hollow bricks, made waterproof by a layer of asphalt laid on kraft paper and a slab of lean concrete. Heating is provided by a low steam, forced air system, where the air is both moistened and filtered. Two heavy oil boilers provide heat and hot water for flats and the ground floor shops and their mezzanines.

It must be added that, at the time of building the I.S.A.I., materials were so difficult to obtain that the building site run out out steel and cement.

Architecturally speaking, the lightness and strength of the buildings in Le Havre result from Perret’s will to expose the structure of the buildings, thus following in the steps of ancient time architects. The various architects of the Perret Studio all agreed on following the principles of Structural Classicism as edicted by their master.

As for materials, this is how he used to justify his choices: “in Le Havre, I use, as always, bush-hammered concrete, which is more beautiful, more durable and nobler than stone.” The colour shades of the in-fill panels decorating the façades and the aggregates used, were chosen subtly so as to obtain a pastel hue (sand, crushed stone, cement). These variations create discreet patterns avoiding monotony over the façades. On the detailed quote sent to builders, the mix used to obtain pink coloured tiles is indicated.

Perret was greatly blamed for his use of vertical windows which, however, flood flats with sunlight and are the result of quasi-philosophical thinking: “Glass walls are for workshops, for tool machines. Man requires vertical windows, which are the true frame for human beings. Horizontal lines express rest and death, vertical lines mean standing up, they mean life”.

For the interior decoration of the I.S.A.I., Auguste Perret suggested using the services of André Beaudouin, local master cabinet maker and interior decorator: “Interior decoration was designed on a modern theme in order to agree with the architecture. I chose a cheerful, bright note for the whole flat, high quality furniture certainly, but which could still be manufactured industrially.” The furniture is light in colour, shows smooth shapes, made of cerused oak or sycamore; its classical simplicity adapts easily to the architecture.