Energy-Efficient Design of Conventional High-Rise Buildings by Façade Modification in Cold and Dry Climates; Case Study of Mashhad City;Running Head: Façade Modification of Conventional Tall Buildings

Energy-efficient buildings reduce energy demand. The parameters of the building envelope, as an interface between the interior of the building and the outdoor environment, can greatly influence energy consumption. The main objective of this study is to ‎optimize the parameters of buildings’ envelopes for reducing energy consumption while ‎considering‏ ‏the common style of architectural design in cold-dry regions. The case study research methodology is used to investigate the effect of various openings characteristics on the energy performance of the building. This paper studied one of the stories of a high-rise residential building as the case study and component blocks were used for the rest of the stories. To find an ‎energy-efficient model for the buildings’ façade, considering the effective parameters, ‎numerous simulations were performed by the EnergyPlus as an energy simulation engine. The factors analyzed in this article included the type of glazing, the type of window frame, the window-to-wall ratio (WWR), and shading placement. The results show that a combination of Low-E ‎glazing ‎ and Argon gas with a 5.98% reduction, a UPVC window frame with a 0.36% ‎reduction, a WWR of 30% with a 1.57% increase, an overhang shading with 20cm thickness ‎and 15cm depth with a 1.12% reduction in annual energy consumption can cause a total ‎reduction of 2.45% in annual energy consumption compared to the initial model.‎‏ ‏These ‎changes did not compromise the required lighting for the interior spaces while reducing the ‎energy consumption of the building.