Impact of building envelope design modification on indoor temperature in classrooms in typical Omani schools

Document Type : Research Paper

Authors

1 College of Engineering and Technology, University of Technology and Applied Sciences, Muscat, Oman..

2 School of Housing, Building and Planning, Universiti Sains Malaysia, Penang, Malaysia.

3 Faculty of Built Environment and Surveying, Universiti Teknologi Malaysia, Johor, Malaysia.

4 Department of Architecture and Building Sciences, College of Architecture and Planning, King Saud University, Riyadh, the Kingdom of Saudi Arabia.

10.30772/qjes.2025.161051.1585
Abstract
In Oman's hot-arid climate, school buildings often experience elevated indoor temperatures due to inefficient building envelope designs, resulting in a heavy reliance on air conditioning systems and high energy consumption. To address this issue, this study aims to evaluate indoor air temperature in typical Omani school buildings and determine how modifications to key envelope components, such as walls, roofs, and glazing, can improve indoor temperature conditions and enhance thermal comfort. A mixed-method approach was adopted, combining field measurements with computer simulation. Indoor temperature and relative humidity were monitored in selected classrooms, while DesignBuilder software was used to model existing conditions and test alternative envelope configurations. This integrated method is appropriate for quantifying the thermal performance of building envelopes under realistic climatic and operational settings. Results showed that baseline classrooms reached average indoor temperatures of 33 °C in summer and 24.5 °C in winter, exceeding recommended comfort limits during hot periods. The most effective design alternative reduced indoor temperature by up to 2.3 °C and increased the number of hours within the comfort range by 29%. The study concludes that optimizing wall insulation, roof composition, and glazing selection can significantly improve indoor thermal comfort and energy efficiency in Omani schools, providing practical design guidance for future educational buildings in hot-arid climates.

Keywords

Crossmark

  1. M. of Education, “Education annual report,” 2017. [Online]. Available: https://home.moe.gov.om/library/119/show/750
  2. NCSI, “Electricity consumption in Oman 2010-2017,” Current Breast Cancer Reports, 2018.
  3. PAEW, “Annual report of the general consumption of water and energy,” Muscat, Oman,” Chemical Engineering Journal, 2018.
  4. A. Al Buloshi and E. Ramadan, “Climate change awareness and perception amongst the inhabitants of muscat governorate, Oman,” Am J Clim Change, vol. 4,
    no. 04, pp. 330–336, 2015. [Online]. Available: https://doi.org/10.4236/ajcc.2015.44026
  5. P. Huovila, “Buildings and climate change: Status, challenges, and opportunities,” United Nations Environment Programme, Sustainable Consumption and
    Production Branch, 2007. [Online]. Available: https://www.uncclearn.org/wp-content/uploads/library/unep207.pdf
  6. “Cibse, building energy and environmental modelling: Applications manual. london: The chartered institution of building services engineers,” 1998.
  7. S. Al-Saadi and K. Al-Jabri, “Energy-efficient envelope design for residential buildings: A case study in oman,” in 2017 Smart City Symposium Prague
    (SCSP), vol. 10, no. 1, p. 1–8, 2017. [Online]. Available: https://doi.org/10.1109/SCSP.2017.7973853
  8. T. Ashrafian and N. Moazzen, “The impact of glazing ratio and window configuration on occupants’ comfort and energy demand: The case study of a school
    building in Eskisehir, Turkey,” Sustain Cities Soc, vol. 47, p. 101483, 2019. [Online]. Available: https://doi.org/10.1016/j.scs.2019.101483
  9. M. Azam, J. Berger, S. Guernouti, P. Poullain, and M. Musy, “Parametric pgd model used with orthogonal polynomials to assess efficiently the building’s
    envelope thermal performance,” J Build Perform Simul, vol. 14, no. 2, p. 132–154, 2021. [Online]. Available: https://doi.org/10.1080/19401493.2020.1868577
  10. B. Al Hattali and N. Husin, “An evaluation study of public schools in the sultanate of oman: Financial and environmental criteria,” in Proceedings of the 2nd
    International Conference on Government and Public Affairs, 2021. [Online]. Available: https://www.academia.edu/70364061/An Evaluation Study of Publi
    c Schools in the Sultanate of Oman Financial and Environmental Criteria
  11. M. Khoukhi and N. Fezzioui, “Thermal comfort design of traditional houses in hot dry region of algeria,” International Journal of Energy and Environmental
    Engineering, vol. 3, p. 1–9, 2012. [Online]. Available: https://doi.org/10.1186/2251-6832-3-5
  12. G. Kokogiannakis, P. Tuohy, and J. Darkwa, “Impact of material surface properties on building performance across a variety of climates,” International
    Journal of Low-Carbon Technologies, vol. 7, no. 3, p. 181–186, 2012. [Online]. Available: https://doi.org/10.1093/ijlct/cts018
  13. A. Sharma, A. Kumar, and K. Kulkarni, “Thermal comfort studies for the naturally ventilated built environments in Indian subcontinent: A review,” Journal
    of Building Engineering, vol. 44, no. 1, p. 103242, 2021. [Online]. Available: https://doi.org/10.1016/j.jobe.2021.103242
  14. N. Ma, D. Aviv, H. Guo, and W. Braham, “Measuring the right factors: A review of variables and models for thermal comfort and indoor air quality,”
    Renewable and Sustainable Energy Reviews, vol. 135, p. 110436, 2021. [Online]. Available: https://doi.org/10.1016/j.rser.2020.110436
  15. G. Kirankumar, S. Saboor, S. Vali, D. Mahapatra, A. Setty, and K. Kim, “Thermal and cost analysis of various air filled double glazed reflective windows for
    energy efficient buildings,” Journal of Building Engineering, vol. 28, p. 101055, 2020. [Online]. Available: https://doi.org/10.1016/j.jobe.2019.101055
  16. C. Mu ˜noz-Viveros, A. P ´erez-Fargallo, and C. Rubio-Bellido, “Influence of the type of solar protection on thermal and light performance in classrooms,”
    Energy Reports, vol. 8, no. 22, p. 5329–5340, 2022. [Online]. Available: https://doi.org/10.1016/j.egyr.2022.04.007
  17. Z. Liu and et al., “Impact of exterior envelope thermal performance on energy demand and optimization strategies for university teaching-office buildings,”
    Scientific Reports, vol. 15, no. 1, p. 15171, 2025. [Online]. Available: https://doi.org/10.1038/s41598-025-00045-y
  18. M. Elnabawi, E. Saber, and L. Bande, “Passive building energy saving: Building envelope retrofitting measures to reduce cooling requirements for a
    residential building in an arid climate,” Sustainability, vol. 16, no. 2, p. 626, 2024. [Online]. Available: https://doi.org/10.3390/su16020626
  19. A. Mohamed, A. Amir, and A. Ragab, “The effect of aerogel glazing on daylight and heat gain in school buildings in hot and dry climate,” Environment,
    Development and Sustainability, vol. 28, p. 1805–1826, 2024. [Online]. Available: https://doi.org/10.1007/s10668-024-04963-1
  20. A. Mohamed, M. Gomaa, A. Amir, and A. Ragab, “Energy, thermal, and economic benefits of aerogel glazing systems for educational buildings in hot arid
    climates,” Sustainability, vol. 15, no. 8, p. 6332, 2023. [Online]. Available: https://doi.org/10.3390/su15086332
  21. M. Elnabawi and E. Saber, “A numerical study of cool and green roof strategies on indoor energy saving and outdoor cooling impact at pedestrian level in a
    hot arid climate,” J .Build Perform Simul, vol. 16, no. 1, p. 72–89, 2023. [Online]. Available: https://doi.org/10.1080/19401493.2022.2110944
  22. R. Hart, H. Goudey, and D. Curcija, “Experimental validation for thermal transmittances of window shading systems with perimeter gaps,” J Build Perform
    Simu., vol. 11, no. 6, p. 705–717, 2018. [Online]. Available: https://doi.org/10.1080/19401493.2018.1436192âĂŔ
  23. H. Abba, R. Majid, M. Ahmed, and O. Gbenga, “Validation of designbuilder simulation accuracy using field measured data of indoor air temperature
    in a classroom building,” Journal of Tourism, Hospitality and Environment Management, vol. 7, no. 27, p. 27171–178, 2022. [Online]. Available:
    https://doi.org/10.35631/jthem.727014
  24. ASHRAE, “Ansi/ashrae standard 55-2020: Thermal environmental conditions for human occupancy. atlanta, ga: American society of heating, refrigerating
    and air-conditioning engineers, inc.” 2020. [Online]. Available: https://www.ashrae.org/technical-resources/bookstore/standard-55-thermal-environmental-c
    onditions-for-human-occupancy
  25. N. Al-Tamimi, A. Qahtan, B. Alotaibi, and M. Abuhussain, “Innovative retrofitting approaches for energy saving in saudi public schools,” Indoor and Built
    Environment, vol. 33, no. 7, p. 1260–1279, 2022. [Online]. Available: https://doi.org/10.1177/1420326X241236876
  26. M. Alwetaishi and A. Taki, “Investigation into energy performance of a school building in a hot climate: Optimum of window-to-wall ratio,” Indoor and Built
    Environment, vol. 29, no. 1, p. 24–39, 2017. [Online]. Available: https://doi.org/10.1177/1420326X19842313
  27. A. Shamseldin, “Environmental assessment for sustainable educational spaces: Optimizing classroom proportions in taif city, ksa,” Sustainability, vol. 17,
    no. 7, p. 3198, 2025. [Online]. Available: https://doi.org/10.3390/su17073198
  28. W. Zhao, P. Mustakallio, S. Lestinen, S. Kilpel ¨ainen, J. Jokisalo, and R. Kosonen, “Numerical and experimental study on the indoor climate in a classroom with
    mixing and displacement air distribution methods,” Buildings, vol. 12, no. 9, p. 1314, 2022. [Online]. Available: https://doi.org/10.3390/buildings12091314
  29. N. Sulong, S. Mustapa, and M. a. Abdul Rashid, “Application of expanded polystyrene (eps) in buildings and constructions: A review,” J Appl Polym Sci, vol.
    136, no. 20, p. 47529, 2019. [Online]. Available: https://doi.org/10.1002/app.47529
  30. A. Al-Abduljabbar, M. Al-Mogbel, S. Danish, and A. El-Leathy, “Insulation performance of building components and effect on the cooling load of homes in
    saudi arabia,” Sustainability, vol. 15, no. 7, p. 5685, 2022. [Online]. Available: https://doi.org/10.3390/su15075685
  31. M. Abdelhafez and et al., “Investigating the thermal and energy performance of advanced glazing systems in the context of hail city, ksa,” Buildings, vol. 13,
    no. 3, p. 752, 2023. [Online]. Available: https://doi.org/10.3390/buildings13030752
  32. H. Leong Wen, M. Abdul Nasir, M. Mohd Salleh, M. Mohd Isa, H. Basher, and Y. Arab, “Influence of glazing material selection and cavity thickness of
    double skin fac¸ ade on the thermal performance of hotel guestrooms in malaysia,” Journal of Advanced Research in Fluid Mechanics and Thermal Sciences,
    vol. 130, no. 2, p. 130–149, 2025. [Online]. Available: https://doi.org/10.37934/arfmts.130.2.130149
  33. “Ashrae handbook - heating, ventilating, and air-conditioning applications. american society of heating, refrigerating, and air conditioning engineers,”
    ASHRAE, 2007. [Online]. Available: https://doi.org/10.1615/atoz.a.american society of heating refrigeration and air-conditioning engineers ashrae inc
  34. M. Alwetaishi and O. Benjeddou, “Impact of window to wall ratio on energy loads in hot regions: A study of building energy performance,” Energies, vol. 14,
    no. 4, p. 1080, 2021. [Online]. Available: https://doi.org/10.3390/en14041080
  35. T. Xue, Y. Wan, Z. Huang, P. Chen, J. Lin, and et al, “A comprehensive review of the applications of hybrid evaporative cooling and solar energy source
    systems,” Sustainability, vol. 15, no. 24, p. 16907, 2023. [Online]. Available: https://doi.org/10.3390/su152416907
Volume 19, Issue 1
Winter 2026
Pages 110-124

Supplementary File

  • Receive Date 01 June 2025
  • Revise Date 14 October 2025
  • Accept Date 28 December 2025