The studies described in the present paper have been developed by the teams involved in the French National Research Programm "ARC Convection Naturelle dans l'Habitat" coordinated by CNRS-PIRSEM (Inte disciplinary Research Programm on Energy and Materials, National Scientific Reseach Center) and suported by AFME (French Agency for Energy Management). After a short description of the experimental facilities of each laboratory, we give some significant results on high Rayleigh number natural convection in rooms.