The land was purchased in exchange for land located at Quai de la Megisserie. Following an invitation to tender, the project of the architects Pellechet and Rohault de Fleury was approved. Rohault de Fleury, the unsuccessful applicant against Garnier for the construction of the opera house, was one of the first architects to use iron and became famous for his construction of glasshouses in the Jardin des Plantes.
The Notaries’ Chamber profited from these techniques, which were at the forefront of progress at the time, particularly through the use of metal beams in the roof.