Eco rehabilitation of 97 housing units 10 boulevard Champollion for energy gain and reduction of tenants’ expenses. The work includes the insulation of facades, the replacement of exterior joinery, and radiators. The operation will make it possible to switch from a consumption before work of 194 kWhEP/m².an (energy label D), to a consumption after works of 89 kWhEP/m².an (label B and BBC level renovation), i.e. a gain of 105 kWhEP/m².an.