Transparency on facades and thermal performance of buildings

In current conditions that pollution of the Earth s environment and overuse of fossil fuels have caused increased greenhouse conditions on Earth, alternative architectural methods should be considered and utilized that can synchronize the architecture with climate to reach sustainable architecture. This is possible through building the construction of structures with suitable architecture for the climate. The creation of such sustainable architecture not only improves the quality of life, but also provides a good relationship with the environment. Sustainable architecture is to meet the needs of residents with the lowest energy consumption and minimal damages to the surrounding environment. All-glass facades were employed since application of modern architecture era in buildings. If no attention is paid to the climate of construction location of the project, orientation of the building according to the climate and creation of appropriate shade in such façades, in case of solar radiation into the inner space during the warm and mild temperatures of the year, the inner temperature will bring no comfort to the residents and the building becomes hotter. Therefore, in order to replace the loss of energy to reach a level of comfort, greater use of energy and fossil fuels would be needed. This leads to increased environmental problems caused by indiscriminate use of fossil fuels. This paper reviews the energy problems of glass facades in the Regional Center Building of Shiraz (warm and dry climate). The building has an entire glass facade to the south and a low glass facade to the north. First, we examined the factors affecting energy losses in the mentioned building. Temperature measurement was carried out by field testing using standard air temperature measurement devices. Then, through software simulations by Energy plus, the thermal state of the building was analyzed. The results show that the southern side of the building with a glass facade toward the direct sunlight is the main cause of heat losses of the building. Therefore, after looking for various solutions, a 180-degree rotation of the building was considered, so that the glass facade to the south with unfavorable condition is transferred to the north with no solar radiation. The results of this study indicate that in order to prevent the building from getting hotter in warm climates, no façade with a high percentage of transparency should be used in the southern side.