This paper concerns with optimum design and performance parameters related to energy management of a small solar house. The house is designed to satisfy the main requirements of electrical power and space heating. The proposed house has a south facing PV module employed for direct converting of solar energy into electricity as well as an air solar collector that is integrated behind the solar module. Integration of the solar collector with the PV module aims to enhance the efficiency as well as to decrease the capital cost of the unit. A heat and mass flow numerical model for the energy and mass balances of the flowing air behind the PV module is developed. Temperature variation of individual rooms inside the house is also considered in the study. The developed model has been employed to determine: an appropriate size for the solar house as regards to the given area of PV module, the optimum mass flow rate through the solar collector, and the best configuration of the solar cell array. The simulation results show that an area of 2 m(2) of the PV module would satisfy an acceptable room temperature in the season of winter with a solar house size of 24-48 m(3). Besides, there would be a significant enhancement in thermal efficiency at high mass flow rate of flowing air through the system. Furthermore, higher thermal efficiency and an acceptable room temperature would be achieved in longitudinal configuration of PV module. (C) 2015 Elsevier Ltd. All rights reserved.