Summer 2026, the hottest ever. But some people have stopped complaining and started doing: The Breathing City case
This summer, we will remember it for the heat. And, probably, for some time to come, we will continue to talk about it as one of the hottest summers we have experienced.
The numbers, after all, leave little room for subjective impressions. According to the European Copernicus service, June 2026 was the second-hottest June ever recorded in Europe and the hottest ever in Western Europe. The average temperature over European land reached 19.14°C, 1.78°C above the 1991–2020 average. In Western Europe, the difference reached as much as +3.06°C. In Italy, France, Spain, Germany and the Benelux countries, anomalies reached 3–5°C.
And July and August continued to put cities, infrastructure and people to the test. The problem, however, is not only how hot it gets. It is where the heat is.
It is an ancient principle applied through contemporary technologies.
A city made of concrete, asphalt and impermeable surfaces absorbs and retains heat. This is the phenomenon known as the urban heat island, which can make urban areas significantly hotter than the surrounding rural areas. The European Environment Agency now considers it one of the main challenges cities face in adapting to heatwaves.
At this point, the question is almost inevitable: what can we do, other than complain?
The most common answer is that an individual cannot change anything unless they act together with others. That is true. But there is another possibility: start small, experiment with solutions that work, and make sure they can be replicated.
Because while a city cannot be rebuilt from scratch, it can gradually be transformed. One roof at a time. One wall at a time. One courtyard at a time.
This, ultimately, is the philosophy behind Breathing City, an association founded in Italy with the aim of raising awareness and supporting people in transforming urban spaces through greenery, green walls, rooftop gardens and intelligent water management.
“I have always been sensitive to environmental issues,” says Luca Marzocchi, founder of Breathing City. “But when my son was born, I felt an even stronger sense of urgency to do something. So I decided to put my professional background at the service of trying to build something concrete.”
Marzocchi’s journey began with seemingly different experiences that, when viewed together, tell a single story: water, earth and sun. Irrigation and water management systems, the production of substrates for plants and rooftop gardens, and the design of photovoltaic systems.
This experience led to the creation of Genera, an integrated system that connects green roofs, photovoltaics, cooling and rainwater recovery. It was an idea developed at a time when talking about these integrations was much less common than it is today, and which was turned into a prototype covering approximately 1,700 square metres, including a filtering garden, a biolake and around 120 square metres of green roof integrated with photovoltaic panels. The system was then subjected to technical testing to measure energy production and water recovery capacity.
But why should we care about a green roof?
The simplest answer is: because it can also matter to our wallets.
A traditional roof exposed to the sun can reach extremely high temperatures. A vegetated roof, on the other hand, uses shading and evapotranspiration to limit surface overheating and the transfer of heat into the building. This is not merely a theory: the European Commission cites experiences in which the introduction of green solutions reduced indoor building temperatures by 4–6°C and electricity consumption associated with cooling by more than 11%.
And then there is water.
A green roof is not simply a roof that becomes green: it can become part of a stormwater management system. Vegetation and storage layers retain some of the rainwater, slowing its runoff. A study conducted in Germany found, under specific experimental conditions, an average rainfall retention of 40% in vegetated systems, compared with 29% for bare substrate.
It is an ancient principle applied through contemporary technologies: water falling from the sky does not necessarily have to go straight down the drain. It can be collected, filtered, stored and used to support vegetation.
The scale changes, but the principle remains the same: fewer surfaces that accumulate heat, and more surfaces capable of absorbing water and releasing moisture back into the environment.
And this is not merely a theoretical vision. A European study estimated that if 35% of urban surfaces across the European Union were transformed through green infrastructure, summer cooling energy demand could be reduced by up to 92 TWh per year, while around 10 km³ of rainwater per year could be converted into “green water”.
Naturally, nobody expects every roof to become a garden tomorrow morning. There are structural issues, costs, maintenance requirements, water availability and, above all, different characteristics for every building. But this is precisely where the idea behind Breathing City comes into play.
“The association’s goal is to create a network of people interested in carrying the initiative forward,” explains Marzocchi. “I would like someone to see what we have done and think: ‘Wait, there is a school, a warehouse, a shop or a house near where I live that could adopt a similar solution.’ And we can help that person from a design and technical perspective.”
A kind of environmental peer-to-peer approach: rather than always waiting for the municipality, the state or someone else to intervene, create a network of people who themselves become concrete examples.
Perhaps this is the perspective from which we should look at the heat in our cities. Not simply as something we have to endure, but as a problem to which we can begin to respond by modifying, centimetre after centimetre, the spaces we already have.
Because one green wall will not change the planet’s climate. One green roof will not stop the climate crisis on its own. But a thousand walls and a thousand roofs start to become something else.
And above all, they remind us of one simple thing: a city does not necessarily have to be all concrete simply because it was built that way. Little by little, it can begin to breathe.
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