eQUEST is a building energy simulation tool comprehensive enough to perform detailed analysis of today's state-of-the-art building design technologies which combines a building creation wizard, an energy efficiency measure (EEM) wizard and graphical reporting with a simulation "engine", derived from the DOE-2. The present study aimed to evaluate Energy Performance of buildings when energy efficiency measures are integrated, using eQUEST software. Energy conservation measures related to external shading, building envelope and heating ventilation and air conditioning (HVAC) systems were considered and the net energy savings are evaluated.