Recently, the world needed a lot of energy to provide consumers' needs to compensate for a shortage of non-renewable resources represented in fossil fuels for energy production. This leads to climate change, the effect of greenhouse gases (GHG) that leads to damage to the environment and people's health. The research discusses the effect of the cooling loads on the building and applied as a case study of a residential building in Egypt as external walls, openings, roofs by using the simulation (Design Builder) program which can create a model housing unit to simulate and test of thermal behavior of building. The results were reached after the simulation process with the high total cooling load value of 2916.15 k.W/h, which can be considered the highest value of the cooling load without any appropriate treatments. After other cases, treatments were used in walls, windows, and roofs to reduce the total cooling Loads to 2207.93 k.W/h.