Author(s): BMC2
Contributor: Frédéric Bonnet Obras, Collectif AJAP14

Vertical corridor

Why are you interested in Grand-Mare? You know, this project did not leave good memories…

During our first call, the unequivocal response of Plaine Normande gave us a glimpse of the complex  and troubled  history  which  led to the renovation, by the architects Arnaud Bical and Laurent Courcier of the agency BMC2, of the five tower blocks of social housing of Grand-Mare  built in 1970 in one of the four neighbourhoods undergoing  urban renewal in the Hauts-de-Rouen.

Two years ago, Venice posed the question about the relevance of modern architecture and its capacity  to continue. In France, a country highly urbanised in the twentieth century, the renovation of modern social housing areas is a considerable  challenge and paradoxically an afterthought, of little interest for architects. Although the resources allocated are considerable,  rash decisions  are some- times taken. The first wave of the ANRU led to many demolitions, sometimes justified but more often than not symbolic, resulting in the disappearance  of an extremely  robust  heritage and housing that was often large and comfortable.


In 2004, the ambitions of the Grand Projet de Ville (GPV) carried forward by the mayor Pierre Albertini and driven by its Director Pierre Vionnet, initiated  a fundamental transformation of the social housing  areas of Hauts-de-Rouen,  focused in particular on the development of new public spaces and facilities and on the connection with the town centre via public transport.

The tower blocks of Grand-Mare are a chroni- cle of a failure foretold;  the history of a gap between the needs of a neighbourhood  and the resources implemented.  In 2004, at the request of the Caisse des Dépôts, with the aim of diversifying owners in the Hauts de Rouen, Plaine Normande  acquired  6 tower blocks in Grand-Mare  committing to their renovation. The favourable context  of the GPV led the landlord to organise an architecture competition based on ambitious  specifications. “The inventive and contemporary architectural  aspect of the renovation of the façades, the comfort and quality of the housing, the recovery and embellishment of the interior and exterior communal areas” were the stated objectives from the start.

Without really any reference to the subject, the agency BMC2 was selected for the com- petition.  The renovation budget was very small, BMC2 presented  an economical  and frugal strategy based on slight adaptations to the poorly redeveloped original architecture (development of the overlay of the concrete and timber fascia) and more fundamental transformations in relation to the top and bottom  of the tower blocks (enlargement of entrance halls and installation of maisonettes and roof terraces).

The agency won the competition with much enthusiasm from its client. However, the studies were Dantean and the result of the first call for tenders indicated construction costs far above the objectives of the client.

The architects restarted  their studies,  the project lost its access to the roofs, the over- hanging balconies, certain angles or glazed aprons, the maisonettes were reduced in size and entrance halls made smaller. In spring

2007, in a context  of rocketing  prices  preceding the economic  crisis, the second call for tenders  moved even further  away from the objectives. The relationship between the architect and its landlord became very strained. In a letter dated 7 May 2007, Arnaud Bical, seeing that the project could not be carried out under acceptable conditions  and that any ambition  of the project  in terms of improving the living environment was disappearing, asked to be released from the contractual obligations.

Plaine Normande acknowledged this and notified BMC2 of the termination. A few months later, relying on another project management team, a new building permit application  was filed. It was refused by the mayor of Rouen, Pierre Albertini  who, in a well-documented letter, advised by the technical actors of GPV, asked Plaine Normande  for a return to the original  project.  In September  2007, Plaine Normande called BMC2 back, recognising with  remote  honesty  the need  to  resume the contract  in order to carry the renovation through to the end under the original architectural ambitions  shared by the city of Rouen. Ironically,  in July 2008, the project  contract was signed for an amount far beyond that of the first call for tenders.

Working on an essentially complex  project, small disputes still ongoing with the contractor bring back bad memories. However this is the short story.  The social  landlord  was a client  which  organised  the consultation, wrote the programme and ensured a balanced financing package for each operation. It was also a manager which rented apartments, drew up inventories, settled neighbours’ disputes  and repaired broken doors. At Plaine Normande like elsewhere, these two functions are separate; they are two different jobs carried out by different people. For the Grand-Mare project, the contracting authority was in Caen, and the manager on site in Rouen.

The bad memories are those of the contract- ing authority,  the same people who did not wish to accompany us to visit the site, six years after its delivery, preferring to send us to their fellow managers at the local office in Rouen. Confronted from one day to the next with difficulties as regards the operation management of social housing, the reality check is often cruel for projects  and the managers are not accustomed to commending the work of those who preceded them, in particular the architects.

Eric Lenoir was the Director of the agency in Rouen. He was one of the members  of the jury which, in 2005, selected BMC2’s project. From the original actors, he is the last one still in place; he is from Rouen and was born in the Hauts de Rouen. It is him who organised the visit, he came with all his team, Grégory Meunier, head of the sector which manages the allocation of housing, the three caretakers of the operation, Grégory Lebrun, Fabrice Chartier and Nathalie Duronceray, and Djamila Ferhati, maintenance employee and long-time resident of the neighbourhood. These people told us the history of this project, that which started upon delivery, when the residents started to return to their homes which they had left for the duration of the project. Here too, their opinions are unequivocal. They praised the transformation  of the tower blocks, told us of the everyday enjoyment and contentment of their work or in the lives of their tenants.

It’s quite funny that you ask me this question three years later, but I have found here a high standard of work, of living. We work in comfortable spaces, with lots of light and attractive materials,  the small mosaic is sublime, it captures the light like it is not allowed and then brings much more. Ultimately  it is not just that, I chose this neighbourhood, I chose this property,  I chose this landlord,  nothing but the quality of the renovation.

But then, why so much resentment with regard to the architects from their client? Was this an over-investment,  a one-off  operation in a negative sense, forced  by the circumstances? Did the landlord use its own funds; was the renovation of Grand-Mare carried out to the detriment of all others?

Nearly 4 million  euros of additional costs, 25%. Technically, it is clearly an error of the project management team. This is obviously a voluntary  transgression  of the architects, an undertaking  for the project  beyond pure contractual logic. Regarding  the result, we can only praise this courage, this battle, at the frontline of the mediocrity, led by Arnaud Bical and Yannick Gourvil, his project manager.

However, beyond the architectural and urban issue, we tried to understand the actual cost of the operation, to evaluate the economic performance objectively. The first indication was given by the manager himself, the vacancy  rate of dwellings  is close to 10%. An indicator  particularly scrutinised by the parent company, the group SNI. It is a very good result which demonstrates  the attractiveness of the operation within the housing market, in a neighbourhood  that is overall in little demand on a regional level.

The expenditure calculated by Plaine Normande indicates that the total cost of the operation was close to 850 euros per square metre of habitable space. In France no social landlord is capable of building a new opera- tion below 1400 euros, almost double the amount.

We are not talking here about the subsidies from which the project benefited, or the positive economic  consequences  on the neighbourhood  or city, the question is not for the mayor of Rouen but for the landlord. We are only talking about the gross cost of the renovation of a thirteen-story tower block  in a deprived neighbourhood.

Purely on an economic  basis? It is a profit- able operation for us” confirms Eric Lenoir, “The few dwellings which remain empty cor- respond  to refusals  that we have made in order not to empty neighbouring buildings.

We receive many applications.  In the evening, people come to check which apartments do not have any lights on in order to support their application.


The Hauts-de-Rouen is one of twelve neighbourhoods in the city. Classed as sensitive urban zones, urban free zones and priority safety zones, it now houses twenty-five thousand inhabitants of a city which has one hundred thousand in total. The place suffers as a result of an image of a deprived  area, skirmishes with the police and burnt out cars in deserted  car parks are a regular feature in the local newspaper.  On the day of our visit, a small battalion of police officers were securing a construction site with surveillance cameras over the paving stones of the shop- ping centre.

However, at the beginning,  during the construction of the first buildings, the dynamic was completely different. The Hauts de Rouen was built as an extension of chic residential areas aimed at executives, like in other cities at that time. There was the idea of living a modern life through collective housing, the tower block in particular. The height was synonymous  with clear views, fresh air, the French were leaving compact and unhealthy city centres for spacious and light apartments adapted to the comforts of modern life.

At the time, it was surgeons who were living in the apartments at Grand-Mare, now we would like to house some nurses but the CHU only sends us the orderlies in difficulty…

The caretakers attest to this decline and the gradual  disappearance of the social diversity which  would  have ensured  the stability of the Hauts de Rouen. They remember the worst times when, in the 1980s, certain landlords moved en masse the most under- privileged populations, the famous clearance operations.

They then talk about the ANRU, the efforts of communities,  the renovations,  the arrival of public transport, the development  of new public spaces. They now explain all the attention they give to allocating housing, their way of maintaining the balance of each landing, stairwell and building.

We understand that the bottom was affected and that modern neighbourhoods like the Hauts de Rouen barely recover and the climb back up will be long. The importance of solidarity in this process between regions should be highlighted, on which the ANRU’s principle is based. Public money from the government, region and local authorities enables the regeneration of neighbourhoods which with- out this would  be forgotten, pushed aside. The first public intervention dates back to the 1990s; the ANRU started up in 2003. Where are we now? What is the news from the front line regarding the renovation of modern neighbourhoods?

A little further on in the Grand-Mare  neighbourhood,  Arnaud Bical shows  us the elegant glass and metal block  shapes built in 1968 by Marcel Lods. The recent history of their development teaches us a lot about the relationship that society has with the modern heritage of these neighbourhoods.

It should be remembered that this operation was, at the time, in 1968, at the forefront  of architectural and technical  innovation.  The project is the result of the work of the GEAI (a research group for industrialised architecture), bringing together glass and aluminium manufacturers  and those in the steel sector (Saint-Gobain, Pechiney and Otua). Plots of twenty dwellings, assembled from scratch from prefabricated  housing, three times less heavy than their concrete equivalents, were built in sixty days. Inside, the removable wooden partitions,  the largely glazed dwellings and entrance halls with natural light from above, opened up large spaces for the entire height of the building.

However, the history is complicated. Although everybody historically recognises the quality of the housing, criticisms of the soundproofing and heating are ongoing.  At the end of the 1990s, the property seemed to have particularly deteriorated  and its demolition  was planned. It was the inhabitants who rallied together  to defend their buildings,  resulting in the purchase  and then the renovation  of eighteen of the twenty-five plots by the property group 3F and its local subsidiary IBS.

On 20 July 2011, there was a fire in one of the renovated buildings, killing two young children and causing an outcry with the people of Rouen who blamed, right up to the mayor’s office, the metal structure and demanded the demolition  of the ‘Lods’.  In November 2011, for above all symbolic reasons, fourteen plots of Grand-Mare were demolished. The four others were to be renovated into offices and one would be graded as a historical monument. This was followed in 2014 by the demolition  of another building  constructed by Marcel Lods on Avenue Jean Rondeaux.

However, the disappearance of this contemporary property  did not constitute  the most unfortunate outcome. In 2015, the relocation  of  tenants  was  ensured  on site  with the construction of one hundred smallter- raced houses. The so-called  rural image of the village house in this modern neighbour- hood with twenty-five thousand inhabitants was bordering  on the ridiculous.  The cheap modenature of the roof  lines replaced  the elegant design of Lods’ metal assemblies, large windows  opening onto the landscape were replaced by small windows,  and small cramped  gardens  meant a lack of privacy between homes.

The houses are too small; people had to sell their furniture to move in

The de-densification goes against the national need for preservation of natural and agricultural areas; the morphology is a fallacy on a thermal  level and a luxury on an economic level.

It is not about writing the morals of a complicated  history  but about  simply  showing the ideological  and cultural decline that has marked  the transformation of social housing neighbourhoods in France for fifty years and about highlighting  the exemplary nature of the renovation of the Grand-Mare tower blocks.  The negative symbolism  of the bar and the tower  block  often leads us to for- get the initial qualities of the housing and deny any economic reality. In addition, in the 1960s, the ambitions  for social housing and the desire to experiment had a universal aim. Now ambitious projects are the exception.


The prix de l’équerre  d’argent,  an architectural prize, awarded in 2011 to Lacaton & Vassal for the renovation of the Bois le Prêtre tower block  in the seventeenth  arrondissement of Paris where the latest projects  like the one of LAN in Lormont  in the Bordeaux suburbs shows that the renovation of con- temporary  neighbourhoods is a major issue for the transformation of cities. Although there are projects of particular interest revealing the capacity of this heritage to take on a second life, we should also recognise that the resources implemented  are exceptional  and do not enable the construction of replicable models.

The renovation of the Grand-Mare tower blocks was a standard commission  and it is here that we recognise its exemplary nature. At the start of the project, when the architects were calculating the compulsory expenditure, the rebuilding  of the heating system, painting of façades,  internal  insulation,  cooling of apartments and exterior fittings, already used  up  three-quarters of the  budget.  In this case, the architectural expression  and economic  strategy  were both aspects  with the same problem.  The project  was relying on an accompanying aesthetic; the trans- formation  work was nearly the same as the maintenance.

The resolution  to the heating  problem  perfectly illustrates this frugal strategy, the illustration of a discrete aesthetic. Above all it is necessary to remember the countless outsulation campaigns carried out for several years on social housing buildings which led to the installation of weak, fragile and rough materials on non-synthetic, robust and compound masonry: stone base, ceramic, terracotta  or precast concrete façades, etc.

During a previous  renovation,  the fitting  of white  plastic  trim on a dark yellow  render, covered up the original tectonic choices based on the stacking of concrete fascia, installing  moreover  an internal ladder from the small window, quite ridiculous  for tower blocks with thirteen floors. The architects tried to come back to the original expression without the luxury or the need to completely transform the façade.

The robust concrete fascia was kept and insulated on the inside. Between them, the installation of white aluminium panels neutralised the impact of the plastic trim and restored  a simple  clarity  at the neighbour- hood level. The major decision not to replace the thousand  or so window  frames fitted  a few years ago released money for the installation of large glazed areas, in the angles of the tower blocks along the entire height. By reducing the volumes from the outside, the majority  of dwellings  now benefit from very light living rooms with expansive views over the distant landscape.

The removal of the ground floor apartments, built in a position with little privacy, beneath the parking area, that were poorly lit, allowed scope for developing the large entrance halls, connecting the bottom level from the roads to the central raised garden. The double height and large glazed façades  completely rein- vent the relationship  with the ground of the imposing tower blocks. The collective space is clear; the entrance halls are an extension of the new position.  The discrete  attention with which BMC2 has organised  these five entrance halls needs to be seen. The ad hoc use of the coloured glass paste, the resin plinth skirting,  concrete  staircase,  the stylish design of metal letter boxes and the high ceilings make it very inviting, nearly chic, ultimately a very sixties ambiance.

The renovation shows an affectionate respect for the architecture  of these tower blocks. It was not a question of inventing a new com- position,  of rebuilding new façades in order to suggest that the architecture is new, in the sense of the image that it reflects.  The difficult economic  context  of the operation led the architects to assess the original qualities and tend to the small pathology  of use that appeared. They kept the stone sills from the windows, replanted a garden, reorganised the fences, they became the archaeologists for this ordinary heritage. We use the word heritage to describe the legacy built in the 1960s.

It is difficult  to compare the tower blocks of Grand-Mare to an eleventh century church. The cultural value of this current production of modern architecture  is not as obvious as the radiant city. However, when we hear about the enjoyment of the caretakers, the pride of the inhabitants, when we measure the project economics, that of the reconstruction of the Lods and finally when we recognise the need for commonplace social housing in France, this heritage becomes valuable.


- BMC2
- Société d'aménagement d'HLM la Plaine Normande – Groupe SNI
- Rehabilitation of 6 blocks and 291 housings
- Rouen
- 2012
- 29000 m²
- 12 M € HT