This paper presents simulations of the energy consumption for heating and cooling of residential building, by using different methods concerning thermal zoning. In this study we compared the simulation results of the single and the detailed zoning strategies. The Zoning is done during model creation to define its complexity. The Simulated models have been performed using the Program Ecotect. According to The results of this study, it was determined that the simulated energy load and indoor temperature were particularly sensitive to the thermal zoning, outdoor temperature and the rate of air exchange.