The optimization of orientation, type of materials and construction detail of facade of residential buildings in Tehran in order to reduce energy consumption

Climate change is a tremendous long-term challenge facing the Earth today. The energy- and thermal-performance of buildings has gained global importance in recent years, due to the aim of maintaining thermal comfort with a more efficient approach. The most important part of the buildings regarding to energy dissipation is the building envelop. Proper building envelop with good thermal behavior, provides the highest thermal comfort in the interior with the least use of mechanical equipment, can greatly save energy. The construction sector must take responsibilities for environmental problems, as in every phase of the construction life-circle energy is consumed at a different level. Construction materials represent an important share of this consumption, and the energy consumed by the building materials during their life cycle becomes a significant parameter in the determination of the energy efficiency of the construction. In this research, focusing on the East, West and South regions of Tehran, the cooling and heating load in buildings at different geographical directions has been compared and in relation to the building façade material and construction details and optimal choices have been proposed. For this purpose, the simulation tool has been utilized using Energy plus software with a design builder interface for thermal analysis. The results of this study show that the heating load of residential buildings in Tehran is higher than the cooling load in the western and northern units and the cooling load of the building is higher than the heating load in the southern and eastern units. This can affect the choice of building orientation according to the type of use (for example, buildings that are more active during the day and in most cases require less heating energy than buildings that are active around the clock). In this regard, the heating load in the west facing units is 8% and, in the north facing units is 15 to 26% more than the cooling load. In south-facing units, the heating load of the building is 11 to 30% and in the east-facing units, the heating load of the building is up to 20% less than the cooling load. Comparison of heating load in southern, northern, eastern and western units shows that the best orientation of the building in Tehran to reduce the heating load of the building are south-facing, east facing (19 to 22% more than the southern unit), west facing (20 to 25% more than southern units) and north facing (30 to 40% more in facades with different materials than southern units). The best orientation of the building in Tehran to reduce the cooling load of the building are the south facing units, north facing units (0.5 to 7.5% in facades with different materials more than the southern unit), west facing units (6.5 to 7% more than the southern unit) and east facing units (10.5 to 11% more than the southern unit). In general (total cooling and heating load) the best orientation of the building in Tehran to reduce energy consumption in the building are south facing and east facing units (about 16% more than the south facing unit), west facing (15 to 17% more than southern units) and north facing (18 to 20% more than southern units). Priorities of selection of facade materials and the construction details in south facing facades due to reducing the total cooling and heating load of the building, are brick facade with dry connection method, concrete panels with dry connection method and stone facades with dry connection method. In north-facing units, this arrangement includes brick facade with dry connection method, concrete panels with dry connection method and stone facades with dry connection method. The best facade material to reduce the overall energy load of the building in the west facing units and walls are concrete panels with dry connection method, brick facade with dry connection method, stone facades with dry connection method. In the east facing units, brick facade with dry connection method, stone facades with dry connection method, ceramic facade with dry connection method and concrete panels with dry connection method be suggested.