Architect's glossary
Technical studies office
A qualified person, whose job is to design the plan of a building and to direct its execution. The profession of architect requires both technical and artistic knowledge. It is now regulated and validated by a state diploma.

In regards to:
One technical design office (BET) is a private or public company made up of technicians and engineers, whose role is to carry out studies to guide and confirm the technical and structural choices of a project.
Specifically, their mission consists of:
- make recommendations based on calculations and analyzes
- propose technical solutions for carrying out the work
- suggest modifications concerning the choices of the sponsor to guarantee the feasibility of the project.
Generally solicited for their expertise by the project manager (most often an architect), or even by the building owner (the end customer), the design offices can be generalist or specialized.
https://www.travauxlib.com/construction/bureau-etudes
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