Energy and Buildings 130 (2016) 244–252 Contents lists available at ScienceDirect Energy and Buildings journal homepage: www.elsevier.com/locate/enbuild Evaluation of energy consumption during production and construction of concrete and steel frames of residential buildings Gholamreza Heravi (Associate Professor) a,∗ , Tina Nafisi (Former Postgraduate) a , Rahimeh Mousavi (Former Postgraduate) b a School of Civil Engineering, College of Engineering, University of Tehran, 16 Azar Ave., P.O. Box: 11155-4563, Tehran, Iran b Department of Civil Engineering, Amirkabir University of Technology, Hafez Street, Tehran, Iran a r t i c l e i n f o Article history: Received 31 May 2016 Received in revised form 5 August 2016 Accepted 25 August 2016 Keywords: Energy consumption Production of material Construction phase Concrete framed building Steel framed building Residential buildings a b s t r a c t There is a growing attention to energy consumption (EC) of buildings during their life cycle. The con- struction phase has been less considered due to its small share of the EC in buildings life cycle, as well as the lack and inconsistency of data, especially in developing countries. The purpose of this research is to evaluate the EC during production and construction (PAC) of concrete and steel frames of residential buildings. To address the mentioned purpose, the EC during PAC of frames of 14 concrete and steel framed buildings in Iran’s capital city, Tehran, is studied. The findings show that the EC during PAC of concrete frames is about 27% less than steel frames. Comparison of EC during various PAC processes shows that production of steel is the most energy consumed process. As an example, considering total area of res- idential buildings constructed in Tehran in 2014, replacing steel frames by concrete could lead to 13% energy saving. Moreover, with respect to optimistic and pessimistic evaluated values of EC during PAC of concrete and steel frames of buildings constructed in the mentioned year, about 43% of energy can be saved. © 2016 Elsevier B.V. All rights reserved. 1. Introduction Nowadays, the optimized EC would be one of the most impor- tant human priorities around the globe, due to energy resources’ limitation and environmental issues. The construction industry is a highly active industry in both developed and developing countries, so the social, economic and environmental indicators of sustainable development are drawing attention [1]. For example, 40% of EC in Europe is related to buildings [2]. In Iran, the equivalent amount is even more than 40% of the total EC [3]. In this regard, the manage- ment of EC related to buildings is more critical than other facilities. A building uses energy throughout all phases of its life cycle including raw material extraction, manufacturing, transportation, construction, operation, demolition, and recycling. Energy in build- ings can be categorized as either operational energy (OE) or embodied energy (EE). The OE includes all energy requirements for lighting, heating, and cooling so as to provide a required comfort level. The EE is the energy used in the mining and resource extrac- tion, resource transportation, building product manufacturing and ∗ Corresponding author. E-mail addresses: heravi@ut.ac.ir (G. Heravi), t nafisi@ut.ac.ir (T. Nafisi), rahimeh2533@yahoo.com (R. Mousavi). component manufacturing, subassemblies or building systems, and also energy required to demolish the building and transport the material to landfill sites [4,5]. Focusing only on the usage phase forgoes the opportunity to reduce other building-related emissions [6], and even if the environmental impacts from construction are small compared to other phases, these impacts may be large when looked at on a national level [7]. This research aims to evaluate EC during PAC of concrete and steel frames of residential buildings. To address the mentioned pur- pose, the EC, included electricity and fossil fuels, by considering major PAC processes of concrete and steel frames of 14 buildings in the developing country of Iran is studied. The results of this study are validated by using Athena EcoCalculator software, and com- paring with some previous studies. This research, also, studies the EC and potential energy saving, regarding the under construction areas of the residential buildings in Iran’s capital city, Tehran, in 2014. Eventually, cost of EC is evaluated and discussed to highlight its importance. 2. Literature review Due to importance of energy around the globe, many studies were carried out to evaluate the EC in buildings. For many years http://dx.doi.org/10.1016/j.enbuild.2016.08.067 0378-7788/© 2016 Elsevier B.V. All rights reserved.