At the heart of the Rues Basses district, the Croix d’Or and Madeleine building project is continuing with a series of major structural interventions aimed at changing the building use while preserving its heritage value.

The Croix d’Or and Madeleine project is progressing, marked in recent months by significant structural works on these emblematic buildings. Listed for their heritage value, the 1902 and 1924 buildings feature heterogeneous structures shaped by more than a century of alterations, requiring extensive upgrading works.

Initial interventions focused on the foundations and underground levels, including foundation strengthening using minijetting columns, basement enlargement through underpinning works, and the construction of a new sewer network beneath the raft slab. These works were complemented by additional underpinning operations for future developments.

The project also involved major works on load-bearing structures. These include demolition and reconstruction of deteriorated slabs, strengthening of the existing steel structure and its conversion into a composite steel-concrete system, as well as slab strengthening using UHPC layers and punching shear reinforcement. Timber floors were also converted into composite timber-concrete slabs.

Finally, vertical circulation and built volumes underwent major adaptations, including demolition and reconstruction of reinforced concrete stair cores, as well as the reconstruction of the connecting building in reinforced concrete.

These operations illustrate the diversity and complexity of an urban construction site, combining geotechnical constraints, heritage requirements and structural engineering. With the structural works nearing completion, the project is entering a new fit-out phase. By 2026, the buildings will meet current standards, enabling the client to sustainably continue its commercial activities in the Rues Basses district.