Study of thermal performance of building roofs in the city of Tehran

Document Type : Research Paper


Department of Mechanical Engineering, Shahrekord University, Shahrekord, Iran


The design of a building can provide the highest thermal comfort in the interior without any mechanical equipment and save energy to a large extent. The roof of a building is an important part for thermal loss. This research studies the thermal performance of 14 conventional roof structures in Tehran city by using designbuilder 4.5. It is found that the polystyrene block performs best compared to other structures. Despite the time and cost required to implement the beam for building roofs, the use of the polystyrene block is recommended. The results indicate that the use of 5 cm of thermal insulation in the structure of the roof results in 5.85% decrease in heat loss during winter and 5.65% decrease during summer. A reverse roof has a more favorable performance on hot days of the year. Also, the performance of roofing with heat insulation is better than that of the reverse roof in cold days.


[1] Mohammad S., Evaluating the Thermal Performance of Wall Construction Materials, Case Study: Residential buildings of Tehran, Journal of Architectural and Urban Arts (2014) 53: 69-78.
[2] Heydari S., Comfort Temperature of Iranian People in City of Tehran, Journal of Architectural and Urban Arts (2000) 38: 5-14.
[3] Swan L.G., Ugursal V.I., Modelling of End-Use Energy Consumption in the Residential Sector, A Review of Modeling Techniques, Renewable and Sustainable Energy Reviews (2009)13: 1819–1835.
[4] Dong B., Cao C., Lee E.S., Applying Support Vector Machines to Predict Building Energy Consumption in Tropical Region, Energy and Buildings (2005) 37 (5): 545-553.
[5] Lee W.S., Kung C.K., Using Climate Classification to Evaluate Building Energy Performance, Energy (2011) 36 (3): 1797-1801.
[6] Zhang Q., Residential Energy Consumption in China and its Comparison with Japan, Canada, and USA, Energy and Buildings (2004) 36 (12): 1217-1225.
[7] Hirst E., Goeltz R., Carney J., Residential Energy Use: Analysis of Disaggregate Data, Energy Economics (1982) 4 (2): 74-82.
[8] Kaza N., Understanding the Spectrum of Residential Energy Consumption: A Quintile Regression Approach, Energy Policy (2010) 38 (11): 6574-6585.
[9] Michalik G., Khan M.E., Bonwick W.J., Mielczarski W., Structural Modelling of Energy Demand in the Residential Sector: 2. The Use of Linguistic Variables to Include Uncertainty of Customer’s Behaviour, Energy (1997) 22: 949–958.
[10] Arabzadeh S. Kazemzadeh S., Investigating the Effective Parameters on Energy Consumption in the Residential Section in Iran, Fourth International Conference on Fuel Consumption Optimization in Building, Tehran (2004).
[11] Tarzaghan S., Bagheri Sabzevar H., Effect of External Wall Insulation Materials on Energy consumption (Case study Yazd), Third National Climate Conference, Building and Energy Consumption Improvement with Sustainable Development Approach, Isfahan(2016).
[12] Viseh S., Mazlumi M., Thermal Insulation of Flat Roofs of Buildings with Reverse Roof System, Building and Energy Consumption Improvement with Sustainable Development Approach, Isfahan (2016).
[13] EnergyPlus Version 8.8.0, Documentation. Engineering Reference, American Society Department of Energy (1996-2017).
[14] ANSI/ASHRAE Standard 140-2004. Building Thermal, Envelope and Fabric Load Tests, DesignBuilder Version 1.2.0 (incorporating EnergyPlus version 1.3.0), American Society of Heating, Refrigerating and Air-conditioning Engineers Incorporated (2006).