Analysis of The Impact of Window Properties On the Main Living Space with The Aim of Daylight Efficiency and Energy Saving in The Hot and Dry Climate of Isfahan

Document Type : Original Article


Department of Architecture, Advancement in Architecture and Urban Planning Research Center, Najafabad Branch, Islamic Azad University, Najafabad, Iran.



Today, considering that the building sector accounts for approximately 30% of the total global energy consumption, the approach of the sustainable architecture model is more emphasized in this area. Windows, as one of the main building elements, play a crucial role in absorbing enough daylight to improve interior space quality and to reduce energy consumption. Therefore, this study aims to design the window optimally considering four window variables, including window-to-floor ratio (WFR), as well as the position and shape of windows in the north and south façades of residential areas in Isfahan City. Finally, the findings indicate the impact of each parameter on daylight and energy consumption by simulating it in the DesignBuilder software. For example, a window with 50% WFR and rectangular shape (ratio of 1:1.5) at the top position of the south façade has optimal conditions in terms of static daylight metrics; however, the same window position at the bottom and middle of the façade will not have acceptable conditions in terms of the metrics. Obviously, other scenarios are not exempt from this rule, and it is complicated to select an optimal model. Consequently, by considering several metrics and evaluating them, it can be claimed that a rectangular window with 40% WFR in the south façade with a ratio of 1:2 at the top position of the façade can provide the optimum model in terms of suitable daylight and energy saving for a residential space in Isfahan and the general requirements of daylighting of the National Building Regulations should be examined considering the proposed glazing to floor ratio and the climate of each region.


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