Driven by a shared ambition to promote off-site construction and strengthen the sector in order to reduce the carbon footprint of the building industry and enhance construction quality, GA Smart Building, in partnership with Grand Paris Aménagement, is designing and delivering the first fully off-site timber housing demonstrator for 60 family units in Saint-Cyr-l’École, Yvelines.
The project addresses multiple challenges: optimizing design and construction to achieve financial balance, meeting high standards for user experience, landscaping, and environmental quality, all while preserving strong architectural value. The off-site construction process also significantly raises the level of quality and finish.
The U-shaped development, with attic levels reaching up to four stories (R+3), includes 60 family apartments ranging from studios to five-bedroom units, spanning a total floor area of 4,000 m². Each apartment meets minimum surface standards for its type, features dual orientation, and most are cross-ventilated. Kitchens benefit from natural light, and loggias provide private outdoor spaces for residents.
Based on a program and technical brief incorporating off-site construction principles developed by GA Smart Building, the public developer Grand Paris Aménagement, and the municipality of Saint-Cyr-l’École an architectural competition was launched in spring 2023. Selection criteria focused on architectural, functional, and environmental quality, as well as carbon footprint reduction.
The unanimous winner was ITAR Architectures, recognized for its innovative use of off-site construction to serve architectural design. The agency proposed unique housing concepts that foster new relationships with outdoor spaces. The Charles Renard Est neighborhood in Saint-Cyr-l’École offers the perfect context for a hybrid, bio-based construction approach.
Landscape design is another major focus of the project. With support from landscape agency LIN, the team developed strategies for water management, rainwater harvesting, and the design of outdoor areas that prioritize natural ground surfaces to support local biodiversity.
This true demonstrator of off-site timber housing construction naturally carries strong environmental ambitions. In addition, it will be NF HQE certified and will comply with the 2025 threshold of the RE2020 standard.
GA Smart Building’s industrial off-site approach enables an exceptionally fast construction timeline. The group manages the entire process from FullBIM digital modeling, to the manufacturing of structural and façade components at its Ossabois facility, and the production of comfort equipment at its Equilab plant in Labège, to on-site assembly. This method minimizes environmental impact and neighborhood disruption while ensuring high build quality and tight scheduling.
Construction is scheduled to start by the end of 2025, with an 18-month work period.
Contact
Sophie Meynet
Managing Director, Residential Real Estate