By establishing the linear regression equations, Carlo and Lamberts developed regression equations to assess the effects of different building envelope influencing factors such as building volume indicator, roof heattransfer coefficient, solar heat gain coefficient, etc. on the electricity consumption on commercial buildings in Brazil. In another study conducted by Bansal and Bhattacharya , the detailed simulation results were used to develop simplified regression equations which can predict a single zone building annual energy demand in addition to maximum heating and cooling loads for the central India weather conditions.