The aim of this paper is to demonstrate the role of shading devices in the improvement of energy efficiency of buildings in hot dusty and dry tropical regions. The effect of shading in reducing the energy consumption of buildings is investigated by considering a case study of a guest house chosen because of its logical design approach to reduce thermal loads. The building plan, measurements, and details on schedules of building usage activities have been used as input data to a simulation program of the building. Based on the inputs, a thermal building model is developed in trnsys 17 simulation program and the effect of external shading on the building has been explored. It is seen that building design and orientation determine the effectiveness of shading. Movable shading over windows has a significant impact reducing temperatures by about 1.5 °C in each thermal zone. The difference in thermal energy loads of the building calculated from modeling simulations of the base case and the control case utilizing movable shading devices is approximately 8%. A programmable logic controllers (PLC)-based movable shading device has been designed to facilitate optimal shading control. The results enable us to draw inferences regarding the additional contribution of the shading factor in energy saving techniques for buildings.