With climate change, and in particular the heat wave last summer, the city is no longer in the odor of holiness. Mineral, polluted, concentrated, it no longer makes you dream. Founder of the PCA-Stream agency, Philippe Chiambaretta was very interested in these issues, whether in his project to “re-enchant the Champs-Elysées” at the request of the Committee of the same name or in the construction of the tower Link in La Défense, which will be, when delivered in 2025, the tallest tower in the business district. For 20 minuteshe returns to the role of the architect and the way of thinking and building the city.
How does the architect, whose work is part of the long term, deal with the brutal environmental changes that we are experiencing today?
Since I created my agency in 2000, what has really marked me is the extent to which we have entered a period of change that is constantly accelerating. These changes are multiple: global warming, extinction of biodiversity, scarcity of resources. If we don’t think about what’s going on, the time of an architectural project is so long that we will necessarily create obsolescence. We must understand these changes and see how we can act on them, knowing that many are not going in the right direction.
What are the consequences for architecture today?
Doing architecture to make a beautiful building, to have fun in a style competition, this is perhaps what we blame this generation for which had a lot of success in the years 1990-2000, it was still the star-system of the archi-star. Basically, what was needed was to make a signature, which is quite an egotistical process. We can ask ourselves whether this approach is not a bit outdated. If I took an ecofeminist approach, I could consider that it is a masculine vision of marking one’s territory, of marking one’s power with symbols, with strong gestures. It really peaked until the 2000s with the Bilbao effect in particular, where each city wanted its monument designed by a star architect to exist on the map.
What are the difficulties faced by the architect today?
We have a way of inhabiting the Earth, especially cities, which is completely disastrous, but we don’t know how to approach the problem. Because it is a phenomenon of immense complexity. All the chain consequences of these dynamic systems have not been taken into account because since the 18th century the world has been divided into silos. That’s why we’re working on this notion of city-metabolism: looking at the city, not as a collection of objects but as a living system. It’s quite understandable if you look at the human body and see how it works. We know that in the body there are several subsystems (blood, respiratory, nervous system), but it is all of these systems that make up the organism. And for the city, an approach similar to that of medicine should be developed.
Can you develop this notion of city-metabolism?
The whole point is to return to an understanding of the living and no longer see ourselves as outside living systems. It means a complete paradigm shift, and considering the city as a metabolism. Like a body made up of different systems: nature, infrastructure (roads, networks), buildings, mobility and the use of this city. And to understand the health of this city, you have to understand the interactions between these different layers. We have to be able to objectify the approach we have, like doctors. Tomorrow, we need to be able to have measurable objective criteria, to then be able to say: “we do such and such an intervention, we want to have such and such a result”. We measure the impact and we correct if it does not work. Just like when you have medical treatment.
And is the car the cancer of the city?
Two opposing models. A 20th century model where the car was the symbol of freedom, of emancipation. The roads movies which fueled our youth, the car was freedom! It’s not that all of a sudden, “all those boomers were jerks who don’t understand today’s problems”. This is opposed to another vision which is that of the misdeeds of the car, for a city of tomorrow, sober with walking, cycling. The problem is quite simple in the heart of cities. In Paris, there is no question about the future of the automobile. Cities have already made this change: Copenhagen, Amsterdam, it’s happening in Italy. It’s becoming such a hell to have a car in Paris. We can judge the method but on the end, I think that within ten years, if there are fewer cars in Paris, it will obviously be more pleasant for Parisians. The question it raises is more to know what does it mean for the suburbs and the people who have to come by car to Paris because there is no public transport. And there will have to be answers to that. With Eole, the Grand Paris Express, things should improve. But this trend is inevitable.
What role can architecture play in the ecological transition?
Architectural transition is one of our lines of research. How to build tomorrow to be low carbon, so as not to have a negative impact on biodiversity? What materials to use? Do we build in concrete, in stalls, in wood? And always try to objectify that. Because there are always fads, such as wood construction. But what happens if you build everything out of wood? Are we going to succeed in keeping up with the forest? Be careful not to rush into solutions.
The recycling of materials is also something that we study a lot. That is to say that for two years, when we renovate a large building, we make an inventory of all the reserves of materials that we are going to deposit and we ask ourselves the question of what we are going to do with them. Can we, for example, use the facade stone by crushing it and making a terrazzo that we will use for the floor? Can we take these ugly light fixtures and turn them into something cool with the help of an industrialist? There is a frontier to explore.
Today, towers seem completely obsolete in the face of the new environmental paradigm, what do you think?
For the carbon footprint of a building, you have to look at its life cycle, not just the act of building. Building a tower takes you five years and after that it will be used for 50-60 years. We must not simply look at the energy and the carbon cost of the construction, which will certainly involve concrete, steel, glass and that, no doubt, is carbon. It is also necessary to take into account the movements of the occupants, the energy to heat and cool this tower. And the question of the ecological aberration of a tower no longer appears so simple. Is making five buildings, even in wooden construction, scattered around Paris where all the people will go by car for forty years is so advantageous in terms of the carbon footprint, compared to a tower which is placed on a transport node in common where no one comes by car? In the tower that we are building, there is not a parking space on 130,000 m². Look, I don’t have the answer today.
With the population increasing, we make the city on the city and we densify, there is no alternative to that. It doesn’t shock me that there are places in the city where you can have a high density with towers. Certainly, the object itself may have a carbon footprint that is worse than that of lower buildings, made of wood, but the whole in a territorial system is not necessarily diabolical. It is not necessarily an ecological disaster. And that’s where it deserves a little measure in the positions we can take.