As part of the interior transformation of a house in Grasse, OMPT GROUPE was called in for the enlargement of an existing opening in a load-bearing masonry wall. The client's goal: to create a wider passage between the kitchen and the living room, while respecting the technical requirements for the stability of the structure.
Preliminary structural study
Before any work began, a full study was carried out by a structural engineer to assess the forces transmitted by the permanent and variable loads on the opening area. This structural assessment made it possible to define a made-to-measure underpinning solution, meeting current standards and the specific features of the existing building.
Implementing the mixed reinforcement: reinforced concrete and steel structure
The work required a combined reinforcement mixing reinforced concrete and steel sections:
- A reinforced concrete column cast in place was built at the foot of the wall, playing an essential role in distributing the vertical loads.
- As a counterpart, a UPN180 counter-column was anchored in the opposite load-bearing wall, taking up the lateral loads and maintaining structural alignment.
- A steel beam of the HEA180 type, installed as a lintel above the enlarged opening, carries the horizontal load and guarantees the rigidity of the whole.
The anchors were made with high-performance chemical anchor bolts and the interfaces were treated to limit thermal bridges and ensure the durability of the structure.
Quality control and finishing
After the reinforcement elements were installed, checks were carried out to verify the alignment, fixity and stability of the structure. The entire system was approved by the structural engineering office. The site was then cleaned and prepared for the finishing work (plastering, cladding, etc.).
This job in Grasse demonstrates OMPT GROUPE's expertise in underpinning, able to handle complex structural openings thanks to the combined use of reinforced concrete and structural steel. Every project is carried out in close collaboration with engineers and in compliance with safety and durability standards.
