HAS Massy (Essonne), for Eiffage Immobilier, project owner, the Swiss international design office KCAP delivered in 2024 Cœur Atlantis, a program of 86 housing units ranging from 45 to 115 m². Area: 6,000 m². Budget: n/a Press release.
Gravity-defying on the outskirts of Paris, Cœur Atlantis is a new 86-apartment building defined by spectacular two-metre cantilevered balconies and rooftop penthouses, which merge charcoal and gold elegance. Inspired by Jane Jacobs's 1961 “eyes on the street” concept, it offers serene, luxurious, leafy courtyard living – and is located a 20-minute train ride from central Paris.
This new housing program in Massy, a suburb undergoing urban transformation, on the southern outskirts of Paris, embodies a dense and robust residential intervention in a constantly evolving context. Characterized by its strategic proximity to Orly airport, and known in France as a major RER and TGV hub; Massy has experienced accelerated growth since the mid-20th century, even if the town remains a maturing Parisian suburb, particularly to the south and southeast of the station.
The south of Massy is defined by numerous new housing estates, offices and, clustered around the train station, a plethora of restaurants, theaters, dentists and daycares, and everything residents expect to find in a neighborhood emerging urban. This new building, with concrete facades painted gold and anthracite, thus contributes to the demographic expansion and densification of Massy, by harmonizing its presence with its environment while retaining the existing urban morphologies.
Coeur Atlantis totals approximately 6,000 m², with 86 units ranging in size from approximately 45 to 115 m². It occupies a corner plot in the Atlantic district of Massy, located at a 45-degree rotation from the north, ensuring that all residences receive sufficient sunlight throughout the day. It is bordered by a very busy boulevard and a tree-lined and less busy cross street: a secondary entrance to the building and its private courtyard, accessible from rue Léonard de Vinci, the main public entrance being located rue Galvani, which demarcates this Massy district.
Shaped like a horseshoe, the building is defined by its vast vector expanses of gold and black, with spectacular two-metre cantilevered balconies extending on all sides except the one facing Galvani Street. The black balconies cast deep, angular shadows that move with the movement of the sun, creating visual rhythms that are always playful and poetic. This theatrical – almost cinematic – effect of the light on the building adds an ethereal sophistication to this otherwise heavily ” anchor ».
To ensure the robustness and durability of the building, concrete poured on site, a construction technique widely used in France, was chosen for its frame. This method accentuates the monolithic character and tactile materiality of the building, emphasizing this know-how and structural authenticity.
Additionally, the use of cast-in-place concrete minimizes the need for additional structural elements, thereby reducing joints and seams where potential weaknesses might otherwise arise. Therefore, the entire complex functions as a unified whole, demonstrating resilience to external forces such as weather, seismic activity and general wear and tear over time.
The application of this technique also makes it possible to obtain smooth and seamless surfaces; to better capture the many shadows that cross them. The building's monolithic structure, spectacular gold and anthracite facades and generously proportioned balconies create a nuanced contrast with the predominantly white buildings that otherwise characterize this emerging district of Massy.
What further differentiates Cœur Atlantis from its neighborhood neighbors is the porosity of the building towards its environment; due to its multiple entrance sequences and courtyard-side houses, accessed through private gardens. Balconies replace private gardens, for houses located on the upper six floors; while duplex rooftop penthouses, with private terraces, offer panoramic skyline views.
The integration of the building into its context draws inspiration from Jane Jacob's 1961 “eyes on the street” principle, which states that the vitality of urban spaces is enhanced when buildings are designed with multiple access points and areas allowing natural surveillance. The approach promotes community cohesion by allowing interaction between building occupants and passers-by.
The many ways to access Coeur Atlantis, its plethora of balconies, private gardens and terraces, blur the lines between indoor and outdoor living. Designed for young families, the building is serene, well connected and bustling Paris is only a few minutes away by train.
