Optimizing Thermal Performance of Double-Wall Systems in Tehran's Climatic Conditions: A Simulation-Based Approach

Hassani, Ashkan; Khoshbakht Bahramani, Shooka; Ghobadian, Vahid

doi:10.22034/ijumes.2025.2057838.1307

Optimizing Thermal Performance of Double-Wall Systems in Tehran's Climatic Conditions: A Simulation-Based Approach

Articles in Press

Document Type : Case Study

Authors

Ashkan Hassani

Shooka Khoshbakht bahramani

Vahid Ghobadian

Department of Architecture, CT.C., Islamic Azad University, Tehran, Iran

10.22034/ijumes.2025.2057838.1307

Abstract

Energy efficiency is an essential part of sustainable urban development strategies, especially in cities with wide temperature ranges like Tehran, where a significant amount of energy is consumed to maintain occupants’ comfort. Double-wall systems with an air cavity can minimize reliance on mechanical heating and cooling sources; however, there
are few quantitative studies of insulation materials in Tehran’s climatic conditions. In this study, we use a simulation-based approach utilizing the DesignBuilder program and EnergyPlus engine to evaluate the thermal performance of eight insulation materials (polystyrene, PVC, rock wool, fiberglass, polyurethane, glass wool, polyurethane foam, and extruded polystyrene) in double wall systems, with insulation thickness ranging from 5 to 15 cm, for a typical residential unit located in Tehran, using the actual climate data to analyze heat transfer .The results showed that both the insulation type and thickness play an important role in energy efficiency. Polyurethane and polyurethane foam delivered the best performance in this study with approximately a 30% reduction in heat transfer at 12 cm thickness. Other materials also exhibited more energy efficiency than a non-insulation process, although performance improvement was limited as thickness increased. The study concludes that high-performance insulation, particularly polyurethane at 12 cm, can effectively enhance thermal efficiency in Tehran’s residential buildings. This research provides a technical basis for optimizing wall systems in urban environments. Future studies should incorporate cost, environmental impacts, and advanced insulation technologies to develop more comprehensive strategies for sustainable building design in Tehran and comparable climates.

Graphical Abstract

Optimizing Thermal Performance of Double-Wall Systems in Tehrans Climatic Conditions: A Simulation-Based Approach

Highlights

Simulation-based optimization of double-wall insulation systems in Tehran’s climate
This study uses DesignBuilder to quantitatively evaluate the thermal performance of eight insulation materials across multiple thicknesses under Tehran’s real climatic conditions.
Polyurethane and polyurethane foam identified as top-performing insulators
Results show that these materials consistently achieve the highest thermal efficiency, especially at increased thicknesses, making them optimal for energy-conscious building designs.
Proposed framework supports material selection for sustainable urban construction
The study introduces a practical optimization model to guide engineers and architects in selecting insulation types and thicknesses that enhance building energy performance in hot-summer, cold-winter climates.

Keywords

Double-wall systems

Thermal insulation

Energy efficiency

Building materials

Tehran city

Simulation analysis

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