The present operation consists of the thermal rehabilitation of 32 collective housing units located at 63 avenue Maginot in Bourg en Bresse with work on the building envelope, common areas and housing. It should be noted that the work will take place on an occupied site. Nevertheless, there were 7 vacant dwellings. The purpose of this heavy rehabilitation is to upgrade the technical and envelope elements of the building in order to guarantee all tenants a better comfort of use and thermal of their housing. The objective is to reduce the energy expenditure of buildings and improve the comfort of tenants. The operation aims at the BBC labeling of housing.