This work is a contribution to understand the thermal behavior of the composite material based on granular cork embedded in plaster. An experimental investigation of its thermal properties was mainly performed using the Flash method and the tiny Hot Plate method in steady state regime. This will allow compare its thermal properties with those of plaster for motivate the proposal that this composite will be used as false ceiling. A comparison of the energy performances of the composite material and plaster was made; it allows deducing a very interesting energy gain. The preliminary findings indicate the composite is better than plaster in term of thermal insulation, energy storage capacity and lightness.