As Europe struggles with increased heatwaves, cities are seeking new ways to keep urban areas cool and liveable
With limited space for new parks and trees, a new creative solution is unfolding, making buildings themselves into green spaces.
Across Spain and Italy, projects such as BIG4LIFE and Life+ A_GreeNet are leveraging the use of green roofs and facades to combat rising temperatures, enhance biodiversity, and enhance urban living.
Turing buildings into living ecosystems
In Spain’s Catalonia region, the BIG4LIFE project is working in Barcelona, Lleida, and El Prat de Llobregat to integrate greenery into existing buildings. This concept, known as building-integrated greenery (BIG), encompasses features such as rooftop gardens and vertical plant-covered walls.
Instead of building new parks, the projects reimagine the urban landscape by adding vegetation directly to structures such as offices, homes, and public facilities. Overall, the goal is to mitigate the urban heat island effect, where dense concrete and metal absorb heat, creating healthier and calmer environments for residents.
One example is an office building in Tibidabo amusement park in Barcelona, where plants grow along the outer walls. In the historic old town, a residential building features a green roof that doubles as a community gathering space.
Sustainable greening for a harsh environment
Urban environments, especially in the Mediterranean, pose challenges for maintaining greenery. Concrete and asphalt intensify heat, while water resources are limited. BIG4LIFE addresses this through xeriscaping, a water-efficient landscaping method that utilises drought-tolerant plants and ground coverings like stones or mulch to minimise water evaporation.
The project is also involving local communities in the maintenance of green roofs and facades. By empowering building owners and residents, the initiative ensures these spaces remain vibrant and sustainable over time.
Recently, a green roof on the L’Artesà Auditorium in El Prat de Llobregat was revitalised after failing due to weed overgrowth. The team replaced it with heat- and drought-resistant plants, such as sedum, a low-maintenance species ideal for rooftop gardens. Camera traps are now used to monitor wildlife activity on these sites, revealing visits from birds such as magpies and sparrows.
A joint European effort to cool cities
BIG4LIFE is part of the Cities Refresh campaign, led by the EU Covenant of Mayors, which promotes nature-based solutions to cool urban spaces. It also complements the New European Bauhaus initiative and the EU Strategy on Adaptation to Climate Change, placing environmental sustainability at the heart of urban development.
Meanwhile, in Italy, the Life+ A_GreeNet project is making similar strides along the Adriatic coast. Combining green walls, restored soils, urban forests, and water features like fountains and lakes, the initiative aims to reduce city surface temperatures by 4–10°C by 2030.
In the heatwave summer of 2023, when prolonged temperatures above 30°C claimed hundreds of lives, A_GreeNet’s Climate and Health Observatory urged for urgent action. Its recommendations included less asphalt and more greenery, which are now being integrated into long-term city planning.
The future of Urban life
Both BIG4LIFE and Life+ A_GreeNet demonstrate that climate action in cities is not just a technical challenge, but also about reshaping how people live, work, and interact with their environment. By transforming buildings into green oases, these projects provide practical and scalable solutions that reintroduce nature to the heart of the city.
