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“Intelligens” is the title of 19th International Architecture Exhibition of La Biennale di Venezia (2025) curated by Carlo. Read here


Atlas of the Senseable City, Carlo Ratti's new book, tackles how the growth of digital mapping, is affecting cities and daily life.




International design and innovation office CRA-Carlo Ratti Associati and Bouygues Immobilier have unveiled the design of ILOW, a new building in Paris that aims to act as a bridge between La Défense, the French capital’s financial powerhouse, and the nearby Tours Nuages (Cloud Towers), one of the most iconic social housing projects of the postwar era. The building, designed in collaboration with Agence d’Architecture Willerval et Associés, is shaped like two open arms connecting two different socio-economic neighborhoods. Moreover, it leverages parametric design to generate a facade that reinterprets the Tours Nuages. CRA has filed building permits to the local municipal authority.

ILOW (pronounced EE-LOW) is located on the margin of La Défense, Europe’s largest business district, in the western part of the Parisian metropolitan area. The building edges towards a neighborhood in the municipality of Nanterre, which is home to the mimetic, soft-shaped “Cloud Towers” designed by architect Émile Aillaud between 1973 and 1981. The Tours Nuages are a bold, pioneering social housing experiment. Pulitzer Prize critic Ada Louise Huxtable defined the towers with their multi-color cloud patterns as “surprisingly beautiful buildings”, while leading art curator Robert Hughes included them in his famous 1980 BBC documentary “Shock of the New”.

CRA’s design aims to bring together two adjacent neighborhoods that have long been socially separated from each other. The building is structured around two wings – like two open arms – with a central green courtyard unfolding between them, connecting ILOW with the neighboring public park. The design provides 12,500 square meters (134,550 square feet) of mixed-function spaces, including offices, a restaurant, and a café. The ground floor is transparent and open to the public, promoting the mixing of different communities, while the top of the building features a roof garden. In short, ILOW strives to create a physical “common ground” that extends on different levels while creating visual connections with the surrounding areas. 

 “We are trying to use design promote social encounters between different people, cultures and social groups,” says Carlo Ratti, founding partner of CRA and director of the Senseable City Lab at the Massachusetts Institute of Technology. “This is what is unique about physical – as opposed to digital – space, something which the pandemic made us all too aware of. We can use architecture to bridge across different social worlds.”

With ILOW, CRA pays tribute to Aillaud’s radical visions, reinterpreting them to develop a contemporary “atmospheric architecture.” The building’s curvaceous façade uses a parametric approach – by which a form unfolds following a mathematical model conceived to satisfy a set of specific, ever-evolving targets or “parameters.” Prefabricated modules of various sizes are arranged to create a curved surface that is designed to follow the sun’s trajectory, guaranteeing the optimum lighting conditions indoors while reducing energy consumption. The focus on environmental sustainability also inspires the project’s name. ILOW is a pun on the French word for “small island”, often used in the turn of phrase un îlot de verdure (an island of greenery), that hints at the building’s low energy consumption. 

ILOW is the latest project by CRA to experiment with office design. The 280-meter-high CapitaSpring under construction in Singapore’s Central Business District, designed jointly by CRA and BIG, features both residences and a tropical forest at its core. When completed later this year, it will be the second-tallest skyscraper in the country. CRA also recently developed the interior design for the headquarters of biotech company Zambon, and just unveiled the design for Sella Group’s Open Innovation Center in Turin. The project leverages digital technologies to encourage social interactions and serendipity in the work environment while opening the buildings towards the surrounding city.




A project by CRA for Bouygues Immobilier

Location: Nanterre, France

Creative Consultancy: Italo Rota

CRA Team: Carlo Ratti, Andrea Cassi (Project manager), Anna Morani, Mario Daudo, Matteo Zerbi, Alberto Benetti, Andrea Fasolo, Valentina Grasso, Federico Riches, Oliver Kazimir, Galla Vallée
CRA Graphic Team: Gary di Silvio, Pasquale Milieri, Gianluca Zimbard



Agence d’Architecture Willerval et Associés (Associate Project Management)

Auris (Research Coordinator)

VP & Green Engineering (Structural and Façade Engineering)

Alto Ingenierie (MEP Engineering)

Acoustique & Conseil (Acoustic Engineering)

Green Soluce (Haute Qualité Environnementale Consultant)

BTP Consultants – Agence Tertiaire (Building Technical Control)

Iliade Ingenierie (Economist)

Systal (Food and Services Consultant)