In collaboration with Payame Noor University and Iranian Geography and Urban Planning Association

Document Type : Research Paper

Author

Assistant Prof, Department of Department of Geography and Urban Planning, Payame Noor University, Tehran, Iran.

10.30473/psp.2026.78043.2816

Abstract

Introduction                               
Amid accelerating urbanization and escalating energy demands in the built environment, enhancing the thermal efficiency of building envelopes has become imperative, particularly in climatically challenging regions.
Methodology
This study investigates and optimizes the thermal behavior of external walls in residential buildings within the cold, mountainous context of Bonab, East Azerbaijan Province, Iran. The building sector accounts for nearly 40% of Iran’s final energy consumption, with a substantial portion attributed to heating and cooling loads. To address this, a hybrid methodology integrating on-site measurements and dynamic energy simulations - conducted using DesignBuilder - was employed to evaluate various wall assemblies and façade configurations across representative residential structures in Bonab.
Results
The analysis encompassed multiple wall constructions, including clay brick, lightweight expanded clay aggregate (Leca), and autoclaved aerated concrete (AAC), combined with extruded polystyrene (XPS) insulation, alongside window-to-wall ratios (WWR) varying between 15% and 45%. Results demonstrate that an AAC–XPS composite wall system delivers optimal thermal performance, achieving a 42% reduction in annual energy consumption relative to conventional clay block walls. Furthermore, a daylight factor between 25% and 35% is identified as the ideal WWR range for Bonab, balancing energy efficiency with sufficient natural illumination. By leveraging localized climatic data and empirical validation.
Discussion and Conclusion
This research provides evidence-based, scalable recommendations for architects, building engineers, and urban planners seeking to advance energy-resilient design strategies in cold, highland climates.

Keywords

Ahmadi, N., & Tavakoli, R. (2023). Parametric optimization of building envelopes in cold climates: A case study of Tabriz. Journal of Building Engineering, 65, 105879.
Ahmadi, N., Tavakoli, R., & Kiani, A. (2023). Field validation of thermal performance simulation in residential buildings: A case study in Northwest Iran. Building and Environment, 228, 109834.
Al-Homoud, M. S. (2021). Performance characteristics and practical applications of common building thermal insulation materials. Building and Environment, 30(1), 7-129.
ASHRAE. (2020). ASHRAE Handbook - Fundamentals. American Society of Heating, Refrigerating and Air-Conditioning Engineers.
Chen, Y., & Liu, Sh. (2024). Robust optimization for building envelope design under climatic uncertainty. Energy and Buildings, 298, 113765.
Garcia, M., Rodriguez, P., & Fernandez, A. (2024). Social and cultural factors in sustainable building design: Lessons from traditional architecture in cold climates. Sustainable Cities and Society, 92, 104563.
Ghorbanian, A., & Naderi, M. (2024). Thermal performance of traditional and modern building materials in cold and arid climates: Case study of Yazd, Iran. Journal of Architectural Engineering, 30(2), 04024006.
Hosseini, M., Rezvani, A., & Naderi, S. (2023). Thermal mass effect on energy consumption in residential buildings of cold regions: A case study in Urmia, Iran. Journal of Thermal Analysis and Calorimetry, 148(2), 212-225.
IEA. (2023). Global Energy Review 2023. International Energy Agency.
Iran Energy Organization. (2024). National report on energy consumption in the building sector. Tehran: Ministry of Energy. (In Persian)
Iran Meteorological Organization. (2024). Climatic statistics and data for Bonab city. Tehran: Iran Meteorological Organization. (In Persian)
Johnson, D. R. (2023). Combined qualitative and quantitative methods in building performance research: Theory and practice. Building Research & Information, 51(1), 43-58.
Kazemi, M., & Salehi, A. (2022). Analysis of window-to-wall ratio in residential buildings of cold and dry climates using energy simulation. Architecture & Environment, 12(2), 89-104. (In Persian)
Kazemi, M., & Tavakoli, H. (2024). Optimization of window-to-wall ratio in cold and arid climates: A case study of Tabriz. Energy and Buildings, 288, 112987.
Kazemi, M., Tavakoli, H., & Hosseini, M. (2023). Validation and calibration of DesignBuilder for simulation of residential buildings in cold climates of Iran. Building Simulation, 16(2), 87-99.
Lee, S., Kim, J., & Park, Ch. (2023). Optimal insulation thickness for building walls in cold climates: A comprehensive energy and economic analysis. Energy and Buildings, 280, 112745.
Li, X., & Chen, Y. (2023). Advanced glazing systems for energy-efficient buildings in cold climates: Performance analysis and optimization. Solar Energy, 251, 87-98.
Liu, B., Wang, Ch., & Zhang, D. (2023). Impact of wall insulation on heating energy consumption in cold climate residential buildings: Field measurement and simulation. Energy and Buildings, 280, 112710.
Mogharrabi, A. (2024). Optimization of residential building envelopes in the cold climate of East Azerbaijan Province. Journal of Architectural Engineering, 32(1), 43-58. (In Persian)
Mohammadi, A. (2023). Investigating the thermal performance of residential buildings in Iran's cold and dry climate. Arman Shahr Architecture & Urbanism, 16(4), 89-102. (In Persian)
Naderi, M., Rezvani, A., & Hosseini, M. (2024). Comparative thermal performance of AAC and LECA blocks in cold and dry climatic conditions. Scientific-Research Journal of Building, 25(3), 109-124. (In Persian)
Naderi, S., & Rezvani, A. (2023). Genetic algorithm optimization for building envelope design in cold climates. Journal of Building Performance Simulation, 16(3), 132-145.
Naderi, S., Hosseini, M., & Rezvani, A. (2024). Optimal window-to-wall ratio for residential buildings in cold and arid climates. Building and Environment, 247, 110943.
Okeil, A. M., & Elsayed, A. (2020). Thermal characteristics and energy saving potentials of low-emissivity coating and aerogel-filled glazing units. Energies, 13(2), 461.
Petrovski, A., Zileska-Pancovska, V., & Zujo, V. (2023). Improving building sustainability by optimizing facade solar illumination use in cold and arid regions. Building and Environment, 232, 110132.
Rezaei, F. (2022). Traditional architecture and indigenous materials in Iran's cold and dry climate. Iranian Architecture Studies, 9(2), 63-80. (In Persian)
Rezaei, M. (2023). Investigating the thermal performance of clay and AAC walls in cold climatic conditions. Architecture & Sustainable Development, 11(3), 75-90. (In Persian)
Rezaeinia, M. (2024). Sensitivity analysis of parameters affecting the thermal performance of residential buildings in cold climates. Scientific Journal of the Faculty of Engineering, 25(1), 119-135. (In Persian)
Rezaeinia, M., Hosseini, M., & Kazemi, A. (2023). Validation of thermal simulation models using field data from buildings in Bonab. Architectural Engineering, 30(4), 109-126. (In Persian)
Shi, Y., Li, J., & Zhang, H. (2023). Multi-objective optimization framework for building envelope design considering energy, economic, and environmental aspects. Applied Energy, 332, 120487.
Smith, J., Brown, A., & Johnson, M. (2023). Mid-rise residential buildings in cold climates: Specific challenges and design strategies. Journal of Building Engineering, 68, 108043.
Wang, L., & Brown, T. (2023). Algorithm selection for building energy optimization: Comparing genetic algorithms and gradient-based methods. Building Simulation, 16(4), 143-160.
Wang, R., Zhang, Q., & Li, X. (2023). Window-to-wall ratio optimization for energy efficiency in cold climate residential buildings: A multi-objective approach. Energy and Buildings, 289, 113042.
Wang, Sh., Chen, Y., & Liu, Zh. (2022). Impact of window-to-wall ratio on energy consumption and daylighting in residential buildings: A comprehensive analysis. Building and Environment, 220, 109276.
Zhang, Da, & Liu, Bin. (2023). Advanced glazing systems for energy-efficient buildings in cold climates: Performance analysis and optimization. Solar Energy, 251, 176-189.
Zhang, Y., & Liu, X. (2022). Field validation of building energy simulation tools: A critical review. Energy and Buildings, 268, 112190.
Zhou, L, & Wang, H. (2023). Performance comparison of different thermal insulation materials for building envelopes in cold climates. Construction and Building Materials, 376, 130985.