Thermal loads are of the most important problems faced by residential spaces to reach thermal comfort. The external envelope of the building is one of the most important factors affecting the thermal gain or loss within the residential spaces. As the designer tries to enhance the natural lighting within the residential spaces, he may sometimes ignore the convex thermal load of the glass used in the openings
Therefore, there are many different reasons to control the amount of solar radiation within the spaces, because increasing in thermal loads leads to an increase in consumption of cooling energy.
The thermal performance of the exterior envelope of the buildings (wall, ceiling, openings, and floor of the building) is one of the most important problems that consume energy in a large amount in order to achieve the requirements of thermal comfort inside the buildings. The thermal loss of single-storey buildings is estimated at 45% of the walls and outside windows, while the thermal loss in the multi-story building is estimated at about 70% of the walls and outside windows.[1] Therefore, the external envelope of the building represents one of the most important factors affecting the achievement of thermal comfort and reduction of thermal loads to reach the highest energy efficiency in residential buildings because of continuous exposure to solar radiation.
The type of glass used and the well-designed sun shading devices can significantly reduce the peak heat acquisition and cooling requirements and improve the natural lighting quality, the annual cooling capacity reduction would reach 5% to 15%.
The aim of this research is to review the modern ideas of the types of glass used in the openings to achieve the highest reduction in the requirements of cooling within the residential spaces and clarify the differences between the different types of glass.
The methodology includes reviewing the literature and the different types of glass used in the openings and methods of treatment of the openings to reduce the thermal loads which gained inside the spaces. The research then deals with the practical study through the simulation of a residential unit (the type of glass used in the openings of clear single glass thickness 6 mm transparent color) to study the effect of the different glass used in the openings as one of the components of the outer cover of a single-oriented housing unit in the 6th of October City on the amount of thermal loads through the Design Builder program, resulting in a decrease in cooling loads by 12.3% in the case of double glass, 17.9% And Single Glass - Low-E coated (22.6%) in the case of double-glazed with Low-E coated.