Effect of Window Area and Proportions of Iwan on Daylight in Adjacent Room: An Investigation in Yazd City

Document Type : Original Article


1 Architecture Department, North Tehran Branch, Islamic Azad University, Tehran, Iran

2 Architecture Department, Bam branch, Islamic Azad University, Bam, Iran


Yazd is located in a hot-dry region with harsh weather conditions. Houses with an iwan were suitable for establishing comfort conditions in the past. An evaluation of the visual comfort conditions in residential courtyard buildings in Yazd city was carried out by investigating the effects of the depth of the iwan and the ratio of the adjacent rooms' openings.  Research is currently being conducted on an optimal model of the iwan in an effort to facilitate sustainable development and increase the use of such a model in contemporary housing. The effect of the parameters was investigated by simulating models containing different proportions of the iwan and sizes of the window in the Design Builder software. The results indicate that the proportion of the iwan and Window Wall Ratio of the adjacent room's window significantly affects the daylight that penetrates into the rooms. For the purposes of this study, climate-based daylight metrics (CBDMs), such as Useful Daylight Illuminances (UDI) with thresholds of 100–3000 lux and Spatial Daylight Autonomy (sDA) over 300 lux. In models with an iwan depth of 1.5 and above, windows from 20% to 60% WWR have the ability to bring a suitable amount of light into the room. This means that by using the iwan, wider windows can be designed without having glare and adding extra thermal load to the building. Results obtained from this research will provide new insight into the concepts of iwan. Furthermore, findings of this research help architect to design spaces with the utilization of daylight.


Main Subjects

  1. Gibson, M. D., 2011. Integrating geometry and light: daylight solutions through performance-based algorithms, in Gamper, B. & Plowright, P. (eds.) Considering Research: Reflecting Upon Current Themes in Architectural Research: Lawrence Technological University, pp. 111-126. ISSN: 1257321897.
  2. Hosseini, S. M., Mohammadi, M. and Guerra-Santin, O., 2019. Interactive kinetic façade: Improving visual comfort based on dynamic daylight and occupant's positions by 2D and 3D shape changes, Building and Environment, 165, pp. 106396. Doi:10.1016/j.buildenv.2019.106396
  3. Nikpour, M., Ghasemi, M. and Fallah, H., 2011. Study of the effectiveness of solar heat gain and day light factors on minimizing electricity use in high rise buildings, International Journal of Civil and Environmental Engineering, 5(1), pp. 21-25. Doi:10.5281/zenodo.1061547
  4. Roshan, M., Kandar, M. Z. B., Nikpur, M., Mohammadi, M. P. and Ghasemi, M., 2013. Investigating the performance of anidolic daylighting system with respect to building orientation in tropical area, Engineering Science and Technology, 3(1). Available at: https://www.academia.edu/download/34144196/ESTIJ-2-2013.pdf
  5. Yazdi, H., Sad Berenji, S., Ludwig, F. and Moazen, S., 2022. Deep Learning in Historical Architecture Remote Sensing: Automated Historical Courtyard House Recognition in Yazd, Iran, Heritage, 5(4), pp. 3066-3080. Doi:10.3390/heritage5040159
  6. Pirnia, M. K. and Memarian, G. H., 2005. Introduction to Islamic architecture of Iran. Tehran: Soroosh Danesh. Soroush Danesh. ISSN:9649611371. [In Persian]
  7. Bolouhari, S., Barbera, L. and Etessam, I., 2020. Learning Traditional architecture for future energy-efficient architecture in the country; Case study: Yazd city, Naqshejahan-Basic Studies and New Technologies of Architecture and Planning, 10(2), pp. 85-93. Available at: http://bsnt.modares.ac.ir/article-2-39832-en.html
  8. Kasmaei, M., 2003. Climate and architecture. Tehran, Iran: Khak Publishing. ISSN:9645583470. [In Persian]
  9. Maleki, B. A., 2011. Traditional sustainable solutions in Iranian desert architecture to solve the energy problem, International Journal on Technical and Physical Problems of Engineering (IJTPE), 3(6), pp. 84-91. Available at: http://www.iotpe.com/IJTPE/IJTPE-2011/IJTPE-Issue6-Vol3-No1-Mar2011/16-IJTPE-Issue6-Vol3-No1-Mar2011-pp84-91.pdf
  10. Zare’ei, M. I. and Mirdehghan Ashkezari, S. F., 2019. Investigating the Interaction between the Residential Architecture Principles in Muzaffarids and Qajar Eras in Yazd from the Perspective of the Solar Energy Orientations, Armanshahr Architecture & Urban Development, 12(27), pp. 83-94. Doi:10.22034/AAUD.2019.92451
  11. Tavassoli, M. 2006. Climatic design of buildings. Tehran.
  12. Nikpour, M., Shamsolmaali, S., Dehghani, H. and Kandar, M. Z., 2012. Creating sustainability in central courtyard houses in desert regions of Iran, International Journal of Energy and Environment, 6(2), pp. 226-233.
  13. Mohammad Alinezhad, F., 2020. Energy Saving through Connection of Sunken Garden with Nature and Passive Cooling in Traditional Buildings of Hot and Dry Climate of Iran, Iranian (Iranica) Journal of Energy & Environment, 11(1), pp. 19-25. Doi:10.5829/ijee.2020.11.01.04
  14. Soflaei, F., Shokouhian, M. and Zhu, W., 2017. Socio-environmental sustainability in traditional courtyard houses of Iran and China, Renewable and Sustainable Energy Reviews, 69, pp. 1147-1169. Doi:10.1016/j.rser.2016.09.130
  15. Taleghani, M., Tenpierik, M. and van den Dobbelsteen, A., 2012. Environmental impact of courtyards—A review and comparison of residential courtyard buildings in different climates, Journal of Green Building, 7(2), pp. 113-136. Doi:10.3992/jgb.7.2.113
  16. Moradi, A. M. and Akhtarkavan, M., 2008. Sustainable architecture in the hot, arid and sunny regions of Iran, IUST International Journal of Engineering Science (Architect Engineering Special Issue), 19(6), pp. 21-29.
  17. Nabil, A. and Mardaljevic, J., 2005. Useful daylight illuminance: a new paradigm for assessing daylight in buildings, Lighting Research & Technology, 37(1), pp. 41-57. Doi:10.1191/1365782805li12
  18. Al-Oraier, F. (2005) Thermal analysis of traditional adobe dwellings in Riyadh City, Saudi Arabia. PhD thesis, Cardiff University (United Kingdom). Available at: https://www.sid.ir/EN/VEWSSID/J_pdf/80720080603.pdf
  19. Nikpour, M., Kandar, M. Z. and Mousavi, E., 2013. Empirical validation of simulation software with experimental measurement of self shading room in term of heat gain, World Applied Sciences Journal, 21(8), pp. 1200-1206. Doi:10.5829/idosi.wasj.2013.21.8.27
  20. Tayari, N. and Nikpour, M., 2022. Investigation on Daylight Quality of Central Courtyard’s Adjacent Rooms in Traditional Houses in Hot Dry Region of Iran: A Case Study Yazdanpanah House, Iranian (Iranica) Journal of Energy & Environment, 13(4), pp. 320-332. Doi:10.5829/ijee.2022.13.04.01
  21. Petersen, A., 1996. Dictionary of Islamic architecture. Psychology Press. ISSN:0415060842.
  22. Mahmoudi, M., 2005. Review the importance of iwan in traditional houses (with special attention to the bam), Fine Arts Journal, 22.
  23. Kuhn, T. E., Bühler, C. and Platzer, W. J., 2001. Evaluation of overheating protection with sun-shading systems, Solar Energy, 69, pp. 59-74. Doi:10.1016/S0038-092X(01)00017-2
  24. Aste, N., Adhikari, R. S. and Manfren, M., 2013. Cost optimal analysis of heat pump technology adoption in residential reference buildings, Renewable Energy, 60, pp. 615-624. Doi:10.1016/j.renene.2013.06.013
  25. Huang, B.-X., Chiou, S.-C. and Li, W.-Y., 2019. Study on courtyard residence and cultural sustainability: Reading Chinese traditional Siheyuan through Space Syntax, Sustainability, 11(6), pp. 1582. Doi:10.3390/su11061582
  26. Kim, G., Lim, H. S., Lim, T. S., Schaefer, L. and Kim, J. T., 2012. Comparative advantage of an exterior shading device in thermal performance for residential buildings, Energy and Buildings, 46, pp. 105-111. Doi:10.1016/j.enbuild.2011.10.040
  27. Kolaitis, D. I., Malliotakis, E., Kontogeorgos, D. A., Mandilaras, I., Katsourinis, D. I. and Founti, M. A., 2013. Comparative assessment of internal and external thermal insulation systems for energy efficient retrofitting of residential buildings, Energy and Buildings, 64, pp. 123-131. Doi:10.1016/j.enbuild.2013.04.004
  28. Stamatakis, A., Mandalaki, M. and Tsoutsos, T., 2016. Multi-criteria analysis for PV integrated in shading devices for Mediterranean region, Energy and Buildings, 117, pp. 128-137. Doi:10.1016/j.enbuild.2016.02.007
  29. Tzempelikos, A., Bessoudo, M., Athienitis, A. and Zmeureanu, R., 2010. Indoor thermal environmental conditions near glazed facades with shading devices–Part II: Thermal comfort simulation and impact of glazing and shading properties, Building and Environment, 45(11), pp. 2517-2525. Doi:10.1016/j.buildenv.2010.05.014
  30. Nabavi, F., Yahaya, A. and Goh, A. T., 2012. Daylight and opening in traditional houses in Yazd, Iran, 28th International PLEA Conference, Lima, Peru. Available at: http://www.plea2012.pe/pdfs/T08-20120129-0036.pdf
  31. Ragette, F., 2003. Traditional domestic architecture of the Arab region. Edition Axel Menges. ISSN:3932565304.
  32. Maleki, B. A., 2012. Natural Daylighting in Iranian Hot and Arid Region, International Journal on Technical and Physical Problems of Engineering, 4(11), pp. 191-196. ISSN: 2077-3528
  33. Li, D. H., 2010. A review of daylight illuminance determinations and energy implications, Applied Energy, 87(7), pp. 2109-2118. Doi:10.1016/j.apenergy.2010.03.004
  34. Athienitis, A. and Tzempelikos, A., 2002. A methodology for simulation of daylight room illuminance distribution and light dimming for a room with a controlled shading device, Solar energy, 72(4), pp. 271-281. Doi:10.1016/S0038-092X(02)00016-6
  35. Kandar, M. Z., Sulaiman, M. S., Rashid, Y. R., Ossen, D. R., MAbdullah, A., Wah, L. Y. and Nikpour, M., 2011. Investigating daylight quality in Malaysian government office buildings through daylight factor and surface luminance, International Journal of Civil and Environmental Engineering, 5(11), pp. 589-594. Doi:10.5281/zenodo.1062582
  36. Nikpour, M., Ghomeshi, M., Moeinzadeh, N. and Ghasemi, M., 2011. Investigating the effectiveness of self-shading strategy on overall thermal transfer value and window size in high rise buildings, International Journal of Civil and Environmental Engineering, 5(2), pp. 103-108. Doi:10.5281/zenodo.1335096
  37. Nikpour, M., Ghomeshi, M., Mojtabaei, H. and Moeinzadeh, S., 2011. Investigating Sustainability in Hot and Dry Climate of Iranian Cites, Through Central CourtyardHouses, The 5th International Conference of the International Forum on Urbanism (IFoU). Available at: http://globalvisions2011.ifou.org/Index/Group%204/FOUA00141-00202P2.pdf
  38. Guedouh, M. S. and Zemmouri, N., 2017. Courtyard building's morphology impact on thermal and luminous environments in hot and arid region, Energy Procedia, 119, pp. 153-162. Doi:10.1016/j.egypro.2017.07.063
  39. Dubois, C., Demers, C. and Potvin, A., 2007. The influence of daylighting on occuopants: comfort and diversity of luminous ambiences in architecture, Proceedings of the solar conference, Cleaveland, Ohio, USA, 7-12 July: Conference Proceedings of the American Solar Energy Society (ASES); American Institute of Architects, pp. 720.
  40. Gunay, H. B., O'Brien, W. and Beausoleil-Morrison, I., 2016. Implementation and comparison of existing occupant behaviour models in EnergyPlus, Journal of Building Performance Simulation, 9(6), pp. 567-588. Doi:10.1080/19401493.2015.1102969
  41. Clarke, J., Janak, M. and Ruyssevelt, P., 1998. Assessing the overall performance of advanced glazing systems, Solar Energy, 63(4), pp. 231-241. Doi:10.1016/S0038-092X(98)00034-6
  42. Crawley, D. B., Lawrie, L. K., Pedersen, C. O., Winkelmann, F. C., Witte, M. J., Strand, R. K., Liesen, R. J., Buhl, W. F., Huang, Y. J. and Henninger, R. H., 2004. EnergyPlus: New, capable, and linked, Journal of Architectural and Planning Research, 21(4), pp. 292-302.
  43. Tayari, N. and Nikpour, M., 2023. Investigating DesignBuilder Simulation Software's Validation in Term of Heat Gain through Field Measured Data of Adjacent Rooms of Courtyard House, Iranian (Iranica) Journal of Energy & Environment, 14(1), pp. 1-8. Doi:10.5829/ijee.2023.14.01.01
  44. Nikpour, M., Kandar, M. Z., Ghasemi, M., Ghomeshi, M. and Safizadeh, M. R., 2012. Heat transfer reduction using self shading strategy in energy commission building in Malaysia, Journal of Applied Sciences, 12(9), pp. 897. Doi:10.3923/jas.2012.897.901
  45. Kirimtat, A., Koyunbaba, B. K., Chatzikonstantinou, I. and Sariyildiz, S., 2016. Review of simulation modeling for shading devices in buildings, Renewable and Sustainable Energy Reviews, 53, pp. 23-49. Doi:10.1016/j.rser.2015.08.020
  46. Nikpour, M., Kandar, M. Z. and Roshan, M., 2013. Empirical validation of IES simulation in term of daylight in self-shading office room in Malaysia, Journal of Basic and Applied Scientific Research, 3(10), pp. 106-112.
  47. Dahanayake, K. K. C. and Chow, C. L., 2017. Studying the potential of energy saving through vertical greenery systems: Using EnergyPlus simulation program, Energy and Buildings, 138, pp. 47-59. Doi:10.1016/j.enbuild.2016.12.002
  48. Lomas, K., Eppel, H., Martin, C. and Bloomfield, D., 1997. Empirical validation of building energy simulation programs, Energy and Buildings, 26(3), pp. 253-275. Doi:10.1016/S0378-7788(97)00007-8
  49. Ahmad, A., Prakash, O., Kumar, A., Hasnain, S. M., Verma, P., Zare, A., Dwivedi, G. and Pandey, A., 2022. Dynamic analysis of daylight factor, thermal comfort and energy performance under clear sky conditions for building: An experimental validation, Materials Science for Energy Technologies, 5, pp. 52-65. Doi:10.3390/heritage5040159
  50. Al-Sakkaf, A., Mohammed Abdelkader, E., Mahmoud, S. and Bagchi, A., 2021. Studying energy performance and thermal comfort conditions in heritage buildings: A case study of murabba palace, Sustainability, 13(21), pp. 12250. Doi:10.3390/su132112250
  51. Ilbeigi, M., Ghomeishi, M. and Dehghanbanadaki, A., 2020. Prediction and optimization of energy consumption in an office building using artificial neural network and a genetic algorithm, Sustainable Cities and Society, 61, pp. 102325. Doi:10.1016/j.scs.2020.102325
  52. Ellis, P. G. and Torcellini, P. A. (2005) Simulating tall buildings using EnergyPlus: National Renewable Energy Lab., Golden, CO (US). Available at: https://www.osti.gov/biblio/15016731.
  53. Lomanowski, B. A. and Wright, J. L., 2009. Modeling fenestration with shading devices in building energy simulation: a practical approach, Proceedings of the 11th International IBPSA Conference, Glasgow, Scotland, pp. 27-30,
  54. Loutzenhiser, P., Manz, H., Felsmann, C., Strachan, P. and Maxwell, G., 2007. An empirical validation of modeling solar gain through a glazing unit with external and internal shading screens, Applied Thermal Engineering, 27(2-3), pp. 528-538. Doi:10.1016/j.applthermaleng.2006.06.016
  55. Hasan, S., Usmani, J. and Islam, M., 2018. Simulation of Energy Conservation in a Building: A Case Study, Iranian (Iranica) Journal of Energy & Environment, 9(1), pp. 10-15. Doi:10.5829/ijee.2018.09.01.02
  56. Kamyab, A., Mahmoodi Zarandi, M. and Nikpour, M., 2023. Investigating the Effect of Different Proportions of Iwan and Window Area of Adjacent Room on Cooling/Heating Load and Energy Consumption in Central Courtyard Model in Yazd, Iranian (Iranica) Journal of Energy & Environment, 14(2), pp. 118-126. Doi:10.5829/ijee.2023.14.02.04
  57. Amleh, D., Halawani, A. and Hussein, M. H., 2023. Simulation-Based Study for Healing environment in intensive care units: enhancing daylight and access to view, optimizing an ICU room in temperate climate, the case study of Palestine, Ain Shams Engineering Journal, 14(2), pp. 101868. Doi:10.5829/ijee.2023.14.02.04
  58. Lm, I., 2013. Approved method: IES spatial Daylight autonomy (sDA) and annual sunlight exposure (ASE), Illuminating Engineering Society.
  59. Dubois, M.-C., 2001. Impact of solar shading on daylight quality. Measurements in experimental office rooms.
  60. Chi, D. A., Moreno, D., Esquivias, P. M. and Navarro, J., 2017. Optimization method for perforated solar screen design to improve daylighting using orthogonal arrays and climate-based daylight modelling, Journal of Building Performance Simulation, 10(2), pp. 144-160. Doi:10.1080/19401493.2016.1197969