Energy Consumption of Contemporary Office Buildings Based on Envelope Materials and Building Dimensions: A Simulation-Based Study in a Semi-Arid Climate (Case Study: Tehran City, Iran)

Moeini, Seyedmahmood; Shaabanian, Mahdi; Saeidipour, Saeid; Moradi, Zahra

doi:10.22034/ijumes.2025.738696

Energy Consumption of Contemporary Office Buildings Based on Envelope Materials and Building Dimensions: A Simulation-Based Study in a Semi-Arid Climate (Case Study: Tehran City, Iran)

Document Type : Case Study

Authors

Seyedmahmood Moeini ¹

Mahdi Shaabanian ²

Saeid Saeidipour ³

Zahra Moradi ²

¹ Department of Architecture, Mal.C., Islamic Azad University, Malayer, Iran

² Department of Architecture, Ha.C., Islamic Azad University, Hamedan, Iran

³ Department of Architecture, Karazin Kharkiv National University, Kharkiv, Ukraine

10.22034/ijumes.2025.738696

Abstract

Buildings are responsible for roughly one-third of global final energy use, and contemporary office buildings rank among the most energy-intensive segments of the non-residential stock. In hot, semi-arid climates the combined influence of envelope material selection and overall building dimensions on office energy demand remains insufficiently quantified, because designers commonly treat thermal and geometric decisions in isolation. This study evaluates how envelope materials (wall insulation, glazing, and roof finish) and building dimensions (window-to-wall ratio, plan aspect ratio, and number of floors) jointly govern the annual energy consumption of a representative contemporary mid-rise office building in Tehran. A validated Design Builder/Energy Plus parametric model was employed, varying one factor at a time across realistic ranges and benchmarking outcomes against Iran’s National Building Code (Topic 19). Model reliability was confirmed against measured indoor temperatures (R² = 0.89; RMSE = 1.1 °C). Results show the demand is strongly cooling-dominated and that glazing type and window-to-wall ratio are the most influential parameters: replacing single glazing with double low-emissivity units lowered energy use intensity (EUI) by about 22%, while an optimal window-to-wall ratio near 30% minimized the total load. Wall insulation captured most of its benefit within the first 5–7 cm, and compact forms (lower aspect ratio, greater height) reduced EUI by roughly 10%. A combined material–dimensional optimization reduced EUI by about 19% (from 150 to 121 kWh/m²·yr). It is concluded that material and dimensional decisions must be co-optimized rather than addressed separately for cost-effective, low-energy contemporary office design in semi-arid regions.

Graphical Abstract

Energy Consumption of Contemporary Office Buildings Based on Envelope Materials and Building Dimensions: A Simulation-Based Study in a Semi-Arid Climate (Case Study: Tehran City, Iran)

Highlights

· Envelope materials and building dimensions were co-evaluated for office energy use in a semi-arid climate.

· A validated DesignBuilder/EnergyPlus parametric model of a Tehran mid-rise office was used (R² = 0.89).

· Glazing type and window-to-wall ratio were the most influential design parameters.

· Double low-E glazing and a window-to-wall ratio near 30% minimized the cooling-dominated demand.

· Combined material–dimensional optimization reduced energy use intensity by about 19%.

Keywords

Building envelope

energy simulation

contemporary office buildings

semi-arid climate

window-to-wall ratio

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