Recent official statistics have shown that Saudi Arabia electricity consumption growth rate at 7%. Buildings primary energy consumption and electricity consumption are 23% and 80%, respectively. This trend of high energy consumption is expected to rise in the upcoming few years. According to governmental statistics, 70% of the buildings in Saudi are not insulated. Furthermore, most of the air-conditioners in existing buildings were installed before enforcing minimum performance standards on air-conditioners. In this paper, an uninsulated existing residential building model was developed and validated against utility data.