The issue of increasing energy consumed in buildings and the need for thermal insulation regulations has become a major concern in Palestine with increasingly alarming warnings of climate change and the depletion of fossil fuels. In this study, the overall heat transfer coefficient U-value in the Palestinian energy-efficient building code was reviewed for walls, floors, roofs, doors, and windows. U-value expresses the amount of heat transfer from the building to the external outside air. U-value was investigated concerning the average value for the U-value (Average U-value), heating degree days, and energy consumption due to the heating load. The investigation in this study suggested a new average U-value of 0.85 W/m 2 .K was suggested which can result in approximately 44% energy saving and make the energy consumption in the Palestinian residential buildings comparable to the values of the International Energy Consumption Codes.