They are an obvious part of Paris, the gray tin roofs. The majority came into place during the 19th century when Napoleon III wanted to get rid of the medieval atmosphere with narrow alleys and make the city more grand with wide boulevards and multi-story buildings.
Zinc, which most of the roofs are made of, was perfect. Malleable and relatively cheap. At that time, the cramped spaces at the top of the houses were inhabited mainly by servants. Now they have been converted into attractive apartments, sometimes with skylights where the sun shines freely.
A forgotten surface
A study that analyzed the consequences of the extreme heat wave in Paris in the summer of 2003 found that those who lived directly under the roofs of houses had four times the risk of dying than others. The tin roofs become like frying pans and the spaces under them like ovens. It is not uncommon for temperatures to reach 50 degrees when the temperature outside is around 30.
Despite the fact that metal roofs make up a large part of the surface of Paris, no one has really looked at them in the work of climate adaptation, says Eytan Levy, architect and co-founder of the start-up company Roofscapes.
He himself grew up high up in an apartment building and knows how unbearable it can be. During his architectural training, he and his classmates began to sketch out a solution that could both contribute to more greenery and make the apartments cooler. The solution was to create wooden decks with plantings on top of the zinc roofs.
The difference is noticeable. One day in July last year with 32 degrees in the air, the thermometer showed 47 degrees in the apartments with original tin roofs. In the premises under the plantings it was barely 30.
The scent of thyme and rosemary wafts from the rooftop of the Académie du Climat, a stone's throw from Paris City Hall. Roofscapes has a pilot planting here that they have established together with the city of Paris and businesses.
We also have a system for harvesting rainwater because there will likely be water restrictions in Paris in the future, says Eytan Levy.
Tough rules
Roofscapes has several projects underway, but there are some obstacles in the way. One is the cost, around 1,800 euros per square meter for a facility similar to the one in the pilot project. Although it is possible to get some subsidies, it is a hefty sum for many building owners. Another is the strong protection that prevents interventions in old houses. This summer, a proposal was made to include health aspects when decisions are made about building conservation protection.
“All these apartments, especially the ones at the top, will become uninhabitable in the coming years. It’s not about making Paris ugly. It’s about protecting the health of the residents,” Dan Lert, deputy mayor and head of the city’s climate plan and transformation, told The New York Times in September.
He is one of those who believes that the application processes currently in place are too slow and not in line with the green transition.
Now the roofs are built to be just roofs, but we see that they can become spaces to hang out and find coolness, says Eytan Levy.
