The challenges of creating sustainable social housing are shared by co-founders of Avenier Cornejo Architectes Christelle Avenier and Miguel Cornejo, and Carles Oliver Barcel, architect at IBAVIChristelle Avenier One of our first projects as a studio was a social housing project for 38 apartments on the edge of central Paris, in Clichy, and it was for this project that we won the AR Emerging awards in 2017 (AR November 2017). Our work has become more diverse since then: we have also designed akindergarten and private housing among other things.Carles Oliver Barcel I believe there isan evolution in your work, from the projects finished around 2016 and your morerecentwork. Your first projects are more expressive in volume, while more recent buildings are more massive, simple, orderly and regular.Christelle Avenier We agree that over time the facades have become more regular and more efficient, in order to put the energy into lowcarbon materials. We wantto design good buildings that are ecological, but this is always a fight within the budget; our work is to make projects where we have mastered the details but they do not cost too much, so that we can put financial resources into materials.Avenier Cornejo Architectes won the AR Emerging awards in 2017 with a design for brick social housing in Clichy, on the outskirts of Paris (lead image). They are currently working with Dchelette Architecture (who were shortlisted in the AR Emerging awards 2024) on a project for social housing made out of stone at ZAC Hbert in Paris (above)Credit:Avenier Cornejo ArchitectesCarles Oliver Barcel Lowcarbon materials are more expensive than others, and this is where our work begins, as architects, to perform the miracle of fittingnatural materials into the budget. Inregular and repetitive ways of building, there is the opportunity to perform this miracle: to recover the vernacular materials at the scale of the city.In a project for eight social housing units in Palma that we designed in 2018 at the Instituto Balear de la Vivienda (IBAVI, theBalearic Housing Institute) and completed in 2021 (AR April 2022), the window openings are not regular, and we adapted the structure to the programme. This made construction more complicated. It was also the first building that we madewith stone vaults, and we took thedecision that the vaults would sit on aconcrete beam. This is not something Iwould do again, not only because of the massive amount of concrete that it needed, but also because this beam became the main character of the space.It is essential to learn from these ongoing processes and to refine designs. We were able to solve this in a more recent project inSanta Eugnia, which is version 2.0. The buildable area was bigger and that allowed us to use three rows of columns rather than two: one row along each facade and one along the middle of thebuilding which the vaults sit on rather than a concrete beam. Both the structure and the facade are very repetitive, to reduce the cost as much as possible; all the stone is local, and the wood is recycled from timber beams.Miguel Cornejo In a metropolis like Paris, the luxury is not only the material but also space. It is a real challenge today. We are fighting to provide nice living spaces for families which is not easy whenyou are working, not only with socialhousing, but also in the private sector, where the purpose is to make money.As architects, we have a lot of power because we decide which materials are used and which are notChristelle Avenier Since the beginning, we have always put a lot of effort into the drawing of the apartment, because in Paris apartments are very small we have to work twice as hard to make them liveable.Miguel Cornejo I think our work has matured and we have identified the two really important things in a project: the luxury of space on the one hand, and noble and healthy materials with simple details onthe other.Carles Oliver Barcel I like to ask architecture students if, having designed the plan and the volume, they then decide the projects material at the very end of term, on the last night and many do. Ifwehave learnt to design buildings that way, ittakes a lot of time to start designing from the material.I had a chance to study the meaning of sustainability at IBAVI. In 2009, we started a project in Formentera (AR July/August 2019), funded by the European nature conservation programme, LIFE+. At first, the LIFE+ programme told us that they were not going to pay for a building and wehad to explain that we were not just designing a building but making visible therelationship between theway we extract and produce materials and how these processes are affecting the ecosystem that we live in. We do not live ina house, but an ecosystem.Every material was studied according tonot only lowcarbon emissions, but also where it was produced and the labour conditions of the workers, to ensure that damage was not done, not only at home butalso in other countries. This model is one for providing global social justice.Since then, we have designed small projects as a means of research to keep testing this way of working and to show other architecture practices, who are entering competitions for social housing onthe Balearic Islands, that this is possible.Carles Oliver Barcel won the AR Emerging awards in 2022. A project for eight social housing units in Palma, Mallorca, completed in 2021 by IBAVI, for whom Oliver Barcel works, was thefirst in which they recovered stone vault constructionCredit:Jos HeviaThe vault structure was optimised in a later project in Santa Eugnia, also on MallorcaCredit:Milena VillalbaIts facade is more regularand repetitive than earlier iterationsCredit:Milena VillalbaMiguel Cornejo I like this approach to sustainability: the idea that we do not live in a house but in an ecosystem. In your context of Mallorca, there is an ecosystem, but there is also another system of mass tourism. Against this context and its many constraints, how are you able to reach this highquality architecture?Carles Oliver Barcel The project of social housing in the Balearic Islands is verycollective, and there are many local architects who are working in this sustainable way; I think this way of working is a reaction to mass tourism on the island and the problems we are facing. We share knowledge, we share recipes, weshare everything. This is different from some cities or universities where it seems that architects are trying to protect their own research. Here, we are happy to provide what we have learnt to other architects. They build on your research andthen you can pick it back up and take itto another level that you would never otherwise be able to reach by yourself.Miguel CornejoI can feel the strength of your community and the collective thought in the architectural production in the materials and in the spaces that you all make. I am very happy to see that it is possible it encourages us to work the same way here, sharing our experiences andknowledge.Carles Oliver Barcel What is next for your practice?Christelle AvenierWe would like to explore more environmentally virtuous materials. We are excited to have the opportunity to explore stone in a social housing project we are working on at ZACHbert in Paris with Dchelette Architecture (p46), made of solid stone both for the structure and the external facade. We would love to next work with raw earth bricks or pis (rammed earth).The construction industry has forgotten how to build tall stone buildingsMiguel Cornejo This is the aim of many ofus here in Paris. It is a special time for construction in France because we are waking up and moving away from concrete building. Instead, many architects in Paris are looking for materials such as stone or straw. But it is not easy to propose these materials when you are making hundreds ofunits of social housing. In big cities there are many constraints: not only economic and political but also in terms of density and scale.Christelle Avenier The building will be 11 storeys high, and we are facing some technical difficulties. All architects working with stone in Paris at the moment are facing the same trouble and we are working together: How did you find the solution forthis? Did you find a solution for that? Weneed a lot of solidarity if we want to succeed, and we are sharing our troubles and exchanging any technical advances.Miguel Cornejo The main challenge we are facing is that the construction industry has forgotten how to build tall stone buildings.Christelle AvenierWe have to remember the way to build in stone, as itwas done before by Haussmann in Paris, but with the regulations of today.Carles Oliver Barcel There is the sameproblem here. In Paris and Mallorca, we areall facing the same challenges: how to recover a material that was absolutely underused. When we started designing social housing in stone, we could not find asingle structural engineer on the island able to design it. There are now many engineers in Spain who can design these kinds of structures. You need very specific collaborators.When I was in Paris with practice Barrault Pressacco (AR November 2022), who design a lot with stone, they took me toa quarry near Paris, and it was good to discover that the quarries in Paris are much healthier than the quarries in Mallorca. Most of the quarries in Mallorca are in danger of extinction; in the last 12 years, 12quarries have closed down. The stone inParis is incredibly strong and that is whyyou can design 11storey buildings outof it.That is not possible in our case; the maximum height would be around five tosix storeys.The scenario that I would like to see is that use of these materials is no longer an isolated experiment, but just a regular way of building. This is how buildings have been built for centuries, so why can they not be now.OliverBarcel iscurrentlyworking on thetransformation of a 17th-century cloister intoa research centre for the vernacular architectureof the Balearic IslandsCredit:Carles Oliver barcelMiguel Cornejo There is a system of economy that was based on a concrete system of building. Now is the time to change it.Carles Oliver Barcel There are ways tochange it: through one of the projects built on Eivissa (Ibiza) by Peris+Toral (ARSeptember 2024), we discovered that rammed earth blocks are produced using the same technology at the factory that is used to produce concrete paving blocks. That means that this factory could very easily, with very low investment, produce rammed earth blocks.Factories and manufacturers need to make this kind of transition and have tochange the model. And as architects, wehave a lot of power because we decide whichmaterials are used and which are not.Itisincredible how we can affect theenvironment in which we live.Opinions expressed in this interview by Carles Oliver Barcel are his alone and do not represent the views of either IBAVI or the regional government2024-11-08Sixten RahlffShare AR November 2024Buy Now