Characterised by its location in a privileged environment, the building renovated by AZC architectes stands out for its six floors staggered on the hillside. The lower floors are reused as car parks and offices, while the upper floors house the new homes.
The project maintains the original character of the building while adapting to contemporary needs. The pre-existing modular structure facilitates the transformation of the space, while on the outside the prefabricated concrete parapets are reused.
Jean Moulin by AZC architectes. Photograph by Julien Hourcade.
Project description by AZC architectes
This project aims to transform a former office building, constructed in 1987 in La Celle-Saint-Cloud by architect Jacques Grellier, into a social residential complex of 69 apartments along with 1,400 sqm of activity spaces. Facing the Château de la Seine Saint Cloud estate, the site benefits from an exceptional setting characterized by the natural hillside terrain.
The building, with a floor area of 5,400 sqm, is situated on a 6,182 sqm plot and is ideally located near the city center and the train station, both within walking distance.
Designed with a post-and-beam concrete structure, the building stands out with its six staggered floors and facades featuring precast concrete spandrels with an exposed aggregate finish.
The two lower levels, initially designated for parking and technical facilities, retain this function, while the four upper levels, previously used as offices, are converted to accommodate residential units. The lowest level (R0) houses technical spaces, 69 parking spaces, and accessible entrances for individuals with reduced mobility, providing direct connection to vertical circulation.
The R1 level, formerly divided between parking and offices, has been cleared of its initial functions to be dedicated to new activities. Pedestrian access is maintained and enhanced by adding a landscaped ramp, offering an easy pathway from the outside.
The upper floors (R2 to R5) have undergone partial structural transformation to meet residential program requirements. A new spatial configuration is achieved by modifying the central voids to expand patios and optimize apartment layouts. These patios, measuring 10.4 meters per side, play a key role in orienting cross-ventilated apartments and accommodating smaller units. The existing staircases, spacious and naturally lit, are preserved to encourage foot traffic, while an existing elevator shaft is also repurposed.
This renovation project, conducted in consultation with heritage authorities, demonstrates the feasibility of adapting a building to contemporary needs while preserving its distinctive architectural character. This approach balances conservation and change, highlighting the effectiveness and durability of the original design choices.
Conservation and Reuse
We have adopted a conservation and reuse strategy based on analyzing the qualitative elements of the existing structure. The building is given a second life by preserving its structure, facades, and most of its cores.
By reusing existing floors, systems, and materials, the project aligns with a qualitative and sustainable development approach. Preserving the site's topography, access points, facades, and the building's character results from a series of decisions within the team, aiming to retain the quality aspects of the existing structure: facades, stairwells, patios.
The functional quality of the apartments is central to the project. Given the atypical configuration of the existing building, the new layout aims to optimize space, ensure evident functionality, and provide various orientations based on each apartment's size.
Structure
Based on a 5.4-meter grid, the structure is easily adaptable for the residential project. With slab-to-slab heights varying from 3.02 to 3.04 meters, the quality of the apartments surpasses that of current new constructions.
Stairwells
Spacious, comfortable, and naturally lit, the staircases are preserved as is. The floor configurations and the sloping terrain benefit the project, allowing the stairwells to remain open, making common areas more welcoming.
Facades
The prefabricated concrete spandrels are cleaned and retained. The window strips are replaced with new insulating glazing and insulated cladding panels where necessary, such as in front of bathrooms. Solar protection is provided by robust, blackout roller shutters that also serve as security features.
Planters
All existing boxes planted on the terraces are reused in arrangements compatible with the new project.
Exterior Space Treatment
The main challenges of the project were related to the site's topography and the necessity of construction in a sparsely populated residential area. With adapted logistics for material and equipment movement, the company committed to minimizing construction nuisances.
The project integrates into the existing environment, closely aligning with the site's local characteristics and the building. The terrain's topography and the appearance of exterior spaces were slightly modified to enhance accessibility to activity spaces and apartments.
The 69 parking plots dedicated to the apartments are all located within the building, at the basement level (R0). The 28 spaces allocated for activities are arranged on the current outdoor parking area, with slight topographical adjustments to ensure accessibility for people with reduced mobility.
Access to the apartments is separated from that of the activity spaces and parking areas. Pedestrian pathways are secured, utilizing durable and low-maintenance materials such as exposed aggregate concrete and grassed areas.
Parking areas, both inside the building and outdoors, are clearly marked, illuminated, and include pedestrian pathways. Spaces are numbered. Shelters for two-wheeled vehicles are enclosed and protected within the building, equipped with attachment points for securing them.
