Volume 22, Issue 1 (2025)
ioh 2025, 22(1): 240-256 |
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Ethics code: IR.IUMS.REC.1403.220
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Rafieepour A, Irvani H, Jafari Nodoushan H, Jafari M J, Alimohammadi I, Moradi Hanifi S et al . The influences of horizontal external window shading on energy savings in the office building. ioh 2025; 22 (1) : 14
URL: http://ioh.iums.ac.ir/article-1-3734-en.html
URL: http://ioh.iums.ac.ir/article-1-3734-en.html
Athena Rafieepour 
, Hasan Irvani , Hamidreza Jafari Nodoushan , Mohammad Javad Jafari , Iraj Alimohammadi , Saber Moradi Hanifi , Mohammad Javad Afshari *
, Hasan Irvani , Hamidreza Jafari Nodoushan , Mohammad Javad Jafari , Iraj Alimohammadi , Saber Moradi Hanifi , Mohammad Javad Afshari *
Air Pollution Research Center, Department of Occupational Health, School of Public Health, Iran University of Medical Sciences, Tehran, Iran. , mohammad.j.afshari13@gmail.com
Abstract: (588 Views)
Background and Aims: Buildings consume more than 40% of global energy, significantly contributing to carbon dioxide emissions. Windows play a key role in heat exchange between indoor and outdoor environments, and external shading can notably impact building heat transfer. This study investigates the effect of horizontal external shading on energy savings in buildings.
Materials and Methods: In this study, external shading was designed and modeled in the form of horizontal blades perpendicular to the window surfaces for a 10-story office-commercial building in Tehran. The blades were designed such that the resulting shadow would fully cover the window surfaces, with a focus on August 1st (the hottest day of the year) when the highest direct solar radiation hits the window surfaces. The effect of the designed external shading on the building’s cooling load was evaluated using the Carrier HAP software.
Results: The results indicated that the eastern and western windows have the most significant impact on the building's cooling load in the morning and afternoon, respectively. The proposed shading reduced the cooling load demand by 9.23%, 11.33%, and 16.37% in July, August, and September, respectively. This led to an electricity cost saving of 108 US dollars during the period. Implementing this shading in a megacity like Tehran could result in substantial energy savings during the summer and enhance thermal comfort.
Conclusion: External shading systems effectively contribute to energy savings, improved thermal comfort, and aesthetic goals. Further research on various shading structures would be beneficial in this context.
Materials and Methods: In this study, external shading was designed and modeled in the form of horizontal blades perpendicular to the window surfaces for a 10-story office-commercial building in Tehran. The blades were designed such that the resulting shadow would fully cover the window surfaces, with a focus on August 1st (the hottest day of the year) when the highest direct solar radiation hits the window surfaces. The effect of the designed external shading on the building’s cooling load was evaluated using the Carrier HAP software.
Results: The results indicated that the eastern and western windows have the most significant impact on the building's cooling load in the morning and afternoon, respectively. The proposed shading reduced the cooling load demand by 9.23%, 11.33%, and 16.37% in July, August, and September, respectively. This led to an electricity cost saving of 108 US dollars during the period. Implementing this shading in a megacity like Tehran could result in substantial energy savings during the summer and enhance thermal comfort.
Conclusion: External shading systems effectively contribute to energy savings, improved thermal comfort, and aesthetic goals. Further research on various shading structures would be beneficial in this context.
Article number: 14
Type of Study: Research |
Subject:
Physical agents at work
Received: 2025/03/5 | Accepted: 2025/07/28 | Published: 2025/03/30
Received: 2025/03/5 | Accepted: 2025/07/28 | Published: 2025/03/30
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