The securing intervention was determined by the state of the pavement of the two terraces on the first floor, the one placed near the Office of the President of the Province and the one of the Lodging of the Prefect. Appropriate surveys have been carried out to detect the surface stratification of the floors without damaging the waterproofing layer already present. It has decided to remove only the floor in terracotta/clinker and its masset, in order to lay out a high performance waterproof protection sheath and subsequent floating floor. In order to avoid damages to the representative rooms and to the conference room placed on the ground floor, it is expected to create, for each terrace, a protective roof made at the same time as the scaffolding. The arranged intervention is also necessary in order to control the cover of the property, which has shown several losses although localized. On the cover, the intervention concerns the installation of lifelines necessary for the projects and future maintenance, located on the highest coverage.