Sustainable Industrialization in the Building Industry ...

ICCREM 2013 CONSTRUCTION AND OPERATION IN THE CONTEXT OF SUSTAINABILITY PROCEEDINGS OF THE 2013 INTERNATIONAL CONFERENCE ON CONSTRUCTION AND REAL ESTATE MANAGEMENT October 10-11, 2013 Karlsruhe, Germany SPONSORED BY

The Construction Institute (CI) of the American Society of Civil Engineers Modernization of Management Committee of the China Construction Industry Association EDITORS

Yaowu Wang, Ph.D. Kunibert Lennerts, Dr.-Ing., Dipl.-Wi.-Ing. Geoffrey Q. P. Shen, Ph.D. Yong Bai, Ph.D., P.E., F.ASCE ASSOCIATE EDITORS Xiaolong Xue, Ph.D. Chengshuang Sun, Ph.D. Zhili (Jerry) Gao, Ph.D, P.E. Yudi Wu Weirui Xue

Published by the American Society of Civil Engineers

Acknowledgments Organized by Harbin Institute of Technology, P.R. China Karlsruhe Institute of Technology, Germany Hong Kong Polytechnic University, P.R. China North Dakota State University, USA Queensland University of Technology, Australia University of Florida, USA Purdue University, USA University of Salford, UK University of the West of England, UK Florida International University, USA National University of Singapore, Singapore Executive Editors Yudi Wu Anshen Liu Yan Li Qiuxuan Tong Lu Wang Wenjing Li Zaihui Zhou Zhihe Yang Manman Shi

Wanhong Wu Guina Ren Yihe Sun Xiao Zhu Qi Chen Longhui Liao Yaxin Wang Chunting Huo Tao Li

Conference Committee Conference Chair Prof. Dr.-Ing. Dipl.-Wi.-Ing. Kunibert Lennerts, Karlsruhe Institute of Technology, Germany Committee Chairs Prof. Yaowu Wang, Harbin Institute of Technology, P.R. China Prof. Geoffrey Q.P. Shen, Hong Kong Polytechnic University, P.R. China International Steering Committee Director Marvin Oey, Construction Institute of ASCE, USA Prof. Yong Bai, North Dakota State University, USA Prof. Jay Yang, Queensland University of Technology, Australia Prof. R. Raymond Issa, University of Florida, USA Prof. Robert Cox, Purdue University, USA Prof. Mustafa Alshawi, University of Salford, UK Prof. Ming Sun, University of the West of England, UK Asso. Prof. Yimin Zhu, Florida International University, USA Prof. George Ofori, National University of Singapore, Singapore

International Scientific Committee Prof. Andrew Baldwin, Loughborough University, UK Prof. Andy van den Dobbelsteen, Technical University Delft, Netherlands Prof. Baisen He, Tianjin University, P.R. China Prof. Changchun Feng, Peking University, P.R. China Prof. Chimay Anumba, Pennsylvania State University, USA Prof. Craig Langston, Bond University, Australia Prof. Denny McGeorge, University of Newcastle, Australia Prof. Derek Walker, RMIT University, Australia Prof. Dongping Fang, Tsinghua University, P.R. China Prof. Frank Schultmann, University of Karlsruhe, Germany Prof. Fuzhou Luo, Xi’an University of Architecture & Technology, P.R. China Prof. Ghassan Aouad, University of Salford, UK Prof. Godfrey Augenbroe, Georgia Institute of Technology, USA Prof. Goran Runeson, University of Technology Sydney, Australia Prof. Graeme Newell, University of Western Sydney, Australia Prof. Guiwen Liu, Chongqing University, P.R. China Prof. Hao Hu, Shanghai Jiaotong University, P.R. China Prof. Heng Li, Hong Kong Polytechnic University, P.R. China Prof. Hong Ren, Chongqing University, P.R. China Prof. Hongyu Liu, Tsinghua University, P.R. China Prof. Hu Cheng, Southeast University, P.R. China Asso. Prof. Zhili (Jerry) Gao, North Dakota State University, USA Prof. Jianguo Chen, Tongji University, P.R. China Prof. Jianting Wang, Tianjin Institute of Urban Construction, P.R. China Prof. Jiayuan Wang, Shenzhen University, P.R. China Prof. Jinxin Tian, Harbin Institute of Technology, P.R. China Prof. Liyin Shen, Chongqing University, P.R. China Prof. K.W. Chau, University of Hong Kong, P.R. China Prof. Martin Betts, Queensland University of Technology, Australia Prof. Martin Fischer, Stanford University, USA Prof. Mengjun Wang, Central South University, P.R. China Prof. Miroslaw J. Skibniewski, University of Maryland, USA Prof. Naoto Mine, University of Kitakyushu, Japan Prof. Patrick X.W. Zou, University of Canberra, Australia Prof. Peter Brandon, University of Salford, UK Prof. Qiming Li, Southeast University, P.R. China Prof. Ruhe Xie, Guangzhou University, P.R. China Prof. Saixing Zeng, Shanghai Jiaotong University, P.R. China Prof. Shizhao Ding, Tongji University, P.R. China Prof. Shouqing Wang, Tsinghua University, P.R. China Prof. Spike Boydell, University of Technology Sydney, Australia Prof. Weixing Jin, Xi’an University of Architecture & Technology, China Prof. Xiaodong Li, Harbin Institute of Technology, P.R. China

Prof. Xueqing Wang, Tianjin University, P.R. China Prof. Yisheng Liu, Beijing Jiaotong University, P.R. China Prof. Yongshi Pang, Guangzhou University, P.R. China Prof. Yongxiang Wu, Harbin Institute of Technology, P.R. China Prof. Yoshito Itoh, Nagoya University, Japan Prof. Yousong Wang, South China University of Technology, P.R. China Prof. Yun Le, Tongji University, P.R. China Prof. Zahir Irani, Brunel University, UK Prof. Zhihui Zhang, Tsinghua University, P.R. China Prof. Zhongfu Li, Dalian University of Technology, P.R. China Prof. Zhuofu Wang, Hohai University, P.R. China Prof. Ziga Turk, University of Ljubljana, Slovenia Organizing Committee and Secretariat General Secretariat Prof. Xiaolong Xue, Harbin Institute of Technology, P.R. China Committee Members Asso. Prof. Chengshuang Sun, Harbin Institute of Technology, P.R. China Dr. Qingpeng Man, Harbin Institute of Technology, P.R. China Dipl.-Ing. Kai Janisch, Karlsruhe Institute of Technology, Germany Dipl.-Wi.-Ing. Heike Schmidt-Bäumler, Karlsruhe Institute of Technology, Germany Mr. Yudi Wu, Harbin Institute of Technology, P.R. China Mr. Weirui Xue, Harbin Institute of Technology, P.R. China

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Sustainable Industrialization in the Building Industry: On the Road to Energy Efficient Construction Management Søren WANDAHL1 and Lene Faber USSING2 1

Professor, Department of Engineering, Aarhus University, 8000 Århus, Denmark, PH (45) 41893216, Email: [email protected] 2 Associate Professor, Department of Mechanical and Manufacturing Engineering, Aalborg University, 9210 Aalborg, Denmark, PH (45) 99407322, Email: [email protected] ABSTRACT Since the Brundtland report in 1987 sustainability has been an issue in all parts of the world, and the focus is increasing in these years. The building industry has in the same period also been under heavy pressure to increase productivity in the same pace as other manufacturing industries. An important question is then how well these two highly relevant areas can go hand in hand. By means of comparing the main ideas and drivers behind sustainability and industrialization respectively, common threads, possible synergies and evident barriers put forward in this discussion paper. The main method is a review to track past merits in the two domains and to detect knowledge gaps that has research potential. A strategic research agenda focusing on energy efficient construction management is outlined showing the need for future focus on combining industrialization in construction management with sustainability and energy concerns in construction management. INTRODUCTION The building industry is continuously undergoing changes. If viewed as an open system the outer context will influence what, how, when and for whom we build. Human mankind has always strived after doing things better and more efficient and in a capitalistic world we strive after doing things cheaper or with higher profit margins. Basically, this effort could be called an industrialization process, and influences both the build products and the building process itself (Bejder et al. 2008). Another influence is buyer preferences and political influence. This evolves in several areas, but in this paper the focus is only on sustainability. The awareness of our environment, global climate and natural resources has initiated a strong sustainable agenda in the building industry. The question is then if it is possible to combine the continuous industrialization of the building industry with a sustainable approach. That is the topic discussed in this paper. The purpose of the paper is, therefore, to look at industrialization and sustainability respectively, and, thereafter, to investigate if any obvious barriers or possible synergies occur in the combination of sustainability and


industrialization in the building industry. The overarching aim is to put forward a strategic research agenda for future energy efficient construction management endeavors. The structure of this discussion paper starts with a short review of industrialization and the historical development. In this an industrialization framework is put forward. This framework suggests that industrialization can take place in an off-site / on-site dimension and in a product / process dimension. The ideas behind sustainability are thereafter explained. Sustainability can be viewed from three different perspectives, namely an environmental, an economical and a social perspective. Drivers behind industrialization and sustainability are compared and finally a feasible approach to sustainable industrialization is discussed. INDUSTRIALIZATION IN BUILDING In society industrialization expresses the process where inhabitants of a country or region are transforming from working mainly in primary trades such as farming, fishing, forestry etc. to working in factories. England is often referred to as the first country beginning the industrialization around the 18th century. In general the western world is industrialized today, but in the third countries industrialization is still ongoing. Today the western world does not speak of industrialization of the society; instead the word is used when talking about improving traditional trades like construction, agriculture, etc. in terms of productivity and efficiency. This is often also called an industrialized process, which is defined as “a process based on factory production and refining of products in large amounts, especially with help of machines”. Hereby, it becomes clear that the opposite of an industrialized production process is craftsmanship. The building industry is among others characterized by a lot of the work is carried out by hand. In construction there should, therefore, be more employees to conduct the production than in e.g. manufacturing industry, which is highly industrialized. Foster and Greeno (2007) mention industrialization in the construction industry as “the rationalization of the whole process of building (which includes the process of design, the forms of construction used and the methods of building adopted), in order to achieve integration of design, supply of materials, fabrication and assembly so that building work is carried out more quickly and with less labor on site and, if possible, at less cost”. Industrialization in the construction industry should, therefore, be considered very broad. When seeking an answer to why we want industrialization, different scenarios occur. In developing countries there might be a need for houses / shelters / facilities in a large scale to a very low cost. In other parts of the world industrialization is part of market strategy for companies to increase their competitiveness. The rationalization of the whole construction process should in both cases increase the production output and lowering the production costs. Labor productivity is, therefore, the most common measurement of how industrialized a process or trade is. Labor productivity is calculated as a ratio of value added compared with the use of labor hours as single production factor (OECD 2001). In Figure 1, the development in labor productivity for the industry in different countries is compared with the average productivity development for the manufacturing industry. This reveals a clear tendency of a modest productivity

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development in the building industry compared to the manufacturing industry (AE 1998). It is not unrealistic to expect a productivity development of 2% per year, which is a common goal in other industries. This would result in a total development to index 150 over a 20-year period. Only the building industry of United Kingdom can present such a development. Index 240 220 200 180 160 140 120 100 80 1980

Average Manufacturing United Kingdom Sweden Denmark Netherland 1985

1990

1995

2000

2005 Year

Figure 1.Development in labour productivity for the building industry own illustration of OECD data. The poor productivity development has a direct effect on the cost of building, which increases, and the problem of expensive houses is what we are facing today. In (EBST 2000) it is argued that a productivity development of 2% p.a. will accumulate to more than a 10% improvement in five years. Such an increase would result in a 4% fall in real prices on building. This lower price would increase the demand, and the productivity would further increase by 1%. This would in total benefit the general Danish welfare with 1.3 billion US$. From this it can be concluded that an unexploited potential for improvement exists (Wandahl et al. 2011). There are several reservations to take when concluding on comparative analysis of productivity, but the tendency is clear. Since 1980 the productivity development in the international building industry has not been overwhelming. Even though Figure 1 indicates that the construction industry not is industrialized; in some areas it is. A lot of building components are produced off site in large amounts in controlled environments, like windows, kitchens, staircases, concrete walls, etc. We tend to call these for system components because they are designed to fit into the building system. Larger modules are also seen produced off site, like elevator shafts, complete bathrooms, and even complete modules of houses. If instead the more broad definition of industrialization in the construction industry is adapted, there are still a huge potential in rationalizing the construction process. The next paragraph will, therefore, explain different generic approached to industrialization of construction.


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APPROACHES TO INDUSTRIALIZATION IN BUILDING The strategies for achieving industrialization can be dived into an off-site / on-site dimension and a product / process dimension (Alinaitwe et al. 2006). Off-site industrialization is often called prefabrication, because the component in mind is produced prior to installing on-site. Prefabrication spans from small components over large size modules to complete houses. It applies factory mechanization to produce and assembly construction components. The factory setting is a more controlled environment where high quality and mass production can be enhanced affordable. The ultimate goal is a radical change that will lead to new buildings, fully constructed with prefabricated elements assembled on site quickly. In the housing industry some systems are already successful. On the other hand, on-site industrialization refers to the application of advanced techniques, materials and tools on building sites. Product industrialization focuses on the technological aspect of construction in terms of products, material, tools and manufacturing techniques. Off-site product industrialization is concerned with large volumes and automated production of building components. When product industrialization is taking place on site it involves often mechanization of assembly methods, with more advanced tools and materials. On the other hand, process industrialization is concerned with how construction participants are cooperating, contractually and informally. On-site process industrialization is seen in areas like lean constructions planning methods, JIT, logistic and also in cooperation thinking like partnering. Off-site process industrialization involves the whole construction process from idea to facility management. Key areas are buildability, value creation, integrated design processes and strategic cooperation. All these factors are illustrated in Figure 2. Lean planning JIT Cooperation

Buildability Lean processing Strategic cooperation

Waste reduction Components Assembly Prefab methods Massproduction Materials Mechanization Automatization

Figure 2.Different approaches to industrialization. To get an idea of recent tendencies within this framework, the historical development of industrialization in the building industry will briefly be described in the next paragraph.


HISTORICAL DEVELOPMENT IN INDUSTRIALIZATION This paragraph serves to describe the historical development of industrialization in the Danish construction industry. By doing this, some general trends in the development surfaces. These observations are possible very general and hence valid in other European countries – even though this not is investigated. In the period after World War 2 the industrialization of the construction industry was slower compared to other industries. One of the reasons was that material suppliers primarily was extraction of raw materials with very little refinement, e.g. wood, concrete, tile and brick. The main shaping and refinement took place on site. The leading trades were bricklayers and carpenters. These two trades stand for app. 60% of the production costs (Boligministeriet 1997). By the ending of the 40’ies the urbanization speeded up. This created a high demand for housing in the major cities. This combined with the lack of materials and trained craftsmen was a threat to the general welfare. More capacity was hence necessary in construction companies. The Danish government, therefore, established the first department for housing. Shortly thereafter the department created an act that supplied government funding to prefabricated element housing which at that time was a new construction form and also a shift in material. The industrialization of other manufacturing industries speed up in this period, and consumers started to expect the same development in the construction industry. In the early 60’ies prefabrication and system product had become common. This was products like, windows, doors, kitchens, stairs, etc. The use of prefab concrete elements created a demand for a new player on the construction site; the general contractor. The use of these prefab elements also created a demand for more project engineering. The design could now be a part of a building contract, and by this the design-build contracts supplemented design-bid-build contracts. In the 70’ies it was concluded that the construction industry now had enough capacity to handle the future demand. This was among others achieved by have more and more parts produced off site. This industrialization was mainly centered on the main construction components, e.g. the core structure, whilst installations and surfaces still was a trade job on site. In 1972 the activity of prefab element housing peaked. Despite a productivity increase in this period, the cost of housing stayed at the same level, among other because an increased interest level, higher lot prices and higher contribution margins. Through the 80’ies the volume in new build housing decreased dramatically, in fact the volume was halved. This stagnation continued in the 90’ies, and in 1992 Denmark reached the lowest level of activity in new build of housing since World War 2. Since we did not build new houses we had to live with those we had. But by the ending of the millennium severe critic of the prefabricated building mass erected in the 60’ies and 70’ies was launched. People did not live very well in these large concrete blocks, and the quality of the buildings was low and in particular the indoor environment was bad. Based on this, people demanded smaller and more individual houses. The dominating housing form then became low dense family houses. This housing form is to-day still the predominant. Parallel to this development the need for renovation increased, which resulted in weakening of the benefits of large scale

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production in construction. At the entering of the new millennium it is well documented that productivity in the Danish construction industry is stagnated, cf. Figure 1. Compared to other industries the productivity development is very poor, and this has resulted in relative more expensive products in the construction industry. There are probably several reasons for the weak productivity development. In the 50’ies to the 80’ies industrialization had only one area in focus. That was prefabrication of building components. What was left was the production process on site, which among others holds the inefficient division of trades, communication and cooperation. The most recent initiatives in the industry are more process than product orientated. For example partnering which aims at a better cooperation between construction companies. The idea of partnering is that by developing common goals and activities the final result will provide all parties more value for money. It is a holistic approach, e.g. the chain is not stronger than the weakest link. In a broad sense this is an industrialization of the process, where focus is on creating value for all parties. In Denmark the partnering concept started around the 90’ies and is still widely used. Whilst partnering has focus on cooperation between management in companies the initiative BygSOL (a Danish acronym for Cooperation and Learning on site) has focus on cooperation between workers on site. From 2003 until 2007 this has been an EU support development initiative with great success. Again this is an example of that the focus in developing the construction industry has shifted to a more soft and process oriented. In the past five years the activity in the Danish construction industry has been overwhelming high. Unemployment rate is as low as 2-4%. Engineers, contractor and architects have been quite busy, and have hence not the same amount of time to spend on each case. This initiated a focus on the competencies of the client. There has never existed and education for professional clients – but now the clients are organized in the Danish clients union. They offer help and different courses to improve the competencies of clients. The mission is to have professional clients that can take the leading part in construction projects. The latest development in the construction industry is Lean Construction. It seems to have a biased focus on both industrialization of the process and the product. An effective on-site planning tool, called the Last Planner System (Ballard 2000) is a central part of implementation of lean construction. Moreover, there is much focus on removing non value adding parts of both the product and the process. But the most industrialized part of lean construction is still the understanding of the construction process as a “real” production process like in other manufacturing industries. In conclusion, the historical development is (a bit generalized) plotted into the industrialization framework. This is illustrated in Figure 3. This clearly shows that the focus has shifted between industrialization on-site and off-site. It is however, quite clear that a movement upwards in the framework has taken place. Industrialization is no longer about developing prefab components and new assembly methods; it is now also to focus on value adding processes in perhaps a long term strategic cooperation with multiple suppliers.

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1980

1940 On-site

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Figure 3.A generalization of the historical development in industrialization in construction. SUSTAINABILITY IN THE BUILDING INDUSTRY

Sustainable development or simply sustainability has worldwide been on the agenda for at least 25 years. The awareness of global warming, pollution and use of natural resources is becoming high, and everybody aggress that sustainability is a positive focus. Sustainability as a term is often associated with issues around “keeping alive”, “continuing”, and “lasting”. The goal of all production is in a wide sense to sustain, because there hardly seems any point to developing if the effort to do so is not sustained. Like all value-laden phrases, the seductive nature of sustainability has meant that many different definitions have been put forward. Much of the literature on sustainability has, therefore, multiplied entities rather than narrowing them down in an effort to ensure more meaningful discourse (Pearce 2006). The most common definition for sustainable development was formulated by the World Commission on Environment and Development, also known as the Brundtland Commission. It states that “Sustainable development is development which meets the needs of the present without compromising the ability of future generations to meet their own needs” (WCED 1987). When reading different definitions, sustainability includes three broad components; social equity, environmental protection, and economic growth; often known as the ‘triple bottom line’ (Parkin et al. 2003). Different literature often advocates only one at the components, which might be due to failure to distinguish definitions of sustainability from the conditions necessary to achieve it (Pearce 2006). Lately, the environmental aspect has surfaced. Issues such as greenhouse gases, extermination of species, natural disasters due to rising world temperatures, etc. have attained attention in media. Much effort is then undertaken to design and produce e.g. zero energy houses, which mainly focuses on environmental and not economic issues. When focus is broader on the development of societies, it must be recognized that human evolution evolves around economy. Sustainability in an economical expression is all about the


generation of human well-being, or welfare, or, an old-fashioned term, utility. Therefore, sustainability is all about making individual well-being per capita rise over time (Pearce 2006). Let us now shift the attention towards sustainability in the construction industry in particular. As a discipline, sustainable construction has been evolving since the late 1980’ies. It continuously gains momentum as increasing evidence about depletion of the environment and environmental loadings becomes obvious. However, regardless of its importance and the expanding foundation of knowledge in the field, sustainable construction is by no means standard industry practice in many world countries. The International Council for Research and Innovation in Building and Construction (CIB) has since 1995 had sustainability as a priority theme, and several other research initiatives now focus of the three aspects. The built environment also provides a synthesis of environmental, economic and social issues. It provides shelter for the individual, physical infrastructure for communities and is a significant part of the economy. (1) Environmental issues in sustainable construction are clearly evident. Construction uses large amounts of production factors in terms of materials and energy. Human mankind has furthermore a tendency towards building assets where possible. The environmental impact is large not only in the process from transforming raw materials into construction material and erection of these on-site, but also in the following long term use phase. (2) The built environment surrounds us, and it is therefore important the constructions we build create social wellbeing and happiness. It is about understanding the reel needs of the people using the buildings and also to understand how a building’s design and function stimulates such feelings. (3) Economical sustainability is about developing a healthy and lasting economic situation for a country or region. The building industry is a major player in all countries, and holds a large part of all workplaces. Different reports also acknowledge that the state of the building industry directly influences the general welfare. APPROACHES TO SUSTAINABILITY ASSESSMENT

Several different approaches to systematics sustainable approaches in the building industry do occur in theory. In common they have a Life Cycle Approach (LCA) to assess the impact of the different undertakings to reduce emissions, energy consumption, recycling, etc. In order to overcome the increasing concern of today’s resource depletion and to address environmental considerations in both developed and developing countries, life cycle assessment (LCA) can be applied to decision making in order to improve sustainability in the construction industry. Energy use in construction is related to where the usage occurs. The total life cycle energy use consists of Initial Embodied Energy, Recurring Embodied Energy, Operational Energy and Decommissioning Energy. A framework for assessing the sustainability in terms of energy usage is illustrated in Figure 4. A very biased research progression has evolved over time in relation to energy assessment in construction. On one hand research has focused on operational energy. This is a very logical approach since the main part of a constructions

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lifecycle is in the operating/use phase time-wise. Journal paper (Sartori and Hestnes 2007) investigates 60 construction cases and concluded that operational energy is by far the largest contributor to the total energy use. They also conclude that there is a linear relation between operating and total energy valid through all the cases. Journal paper (Ramesh et al. 2010) sums op that operating energy adds up to 80-90% of the total energy use for different construction types, such as residential and office housing. On the other hand a research trend of looking into Initial Embodied Energy especially in relation to different types of construction materials shows great interest in research publications. This topic is about sustainable materials and reducing C02 footprint during processing and transportation of construction materials. 1. Extraction of raw materials 2. Transportation 3. Manufacturing/ processing 4. Transportation 5. Construction process 6. Operation 7. Repair and maintenance 8. Demolition 9. Transport to recycle Figure 4.An energy assessment framework in relation to a constructions’ lifecycle.

Improvements within both directions have been significant in the last decade. It is now possible to design low energy, passive and even zero energy hosing. This has gained much interested by media and by clients and users. Important, though, this way of speaking about sustainable housing is not based on a life cycle view, but only limited to an operational view.


DISCUSSION OF STRATEGIC RESEARCH AGENDA ON ENERGY EFFICIENT CONSTRUCTION MANAGEMENT

Although conclusions about energy an environmental performance of a building should be based on the results of a whole life cycle analysis, there are always opportunities to explore each phase individually to collected detailed information and strengthen information databases. It seems that the actual construction of building is the least investigated phase when the scope is lifecycle energy use. A main reason for this historical limited interest in energy use during construction is twofold. Firstly the “return of investment” has so far seemed very low, because only around 7-10% of the total energy use is related to this phase. Secondly, it can (and has been) argued that to minimize energy use during construction is a design task. The design phase outlines the possible scope of events for improving the construction process in general in the construction phase (Wandahl 2004) This is about to change. Modern construction now provides opportunities for low energy and even zero energy housing. The terms “low” and “zero” refers to the energy demand in the use phase. When we have very little energy demand from the use phase, we will have a relative large contribute from the construction phase. In other words, the life cycle ration of energy use in construction is shifting from a relative distribution of 18% Embodied Energy, 80% Operational Energy and 2% Decommissioning Energy towards 85% Embodied Energy, 5% Recurring Embodied Energy and 10% Decommissioning Energy. This shift in focus will dramatically increase the interest in reuse of materials and strengthen the focus on activities on-site. Only few research reports on this issue. (Shrivastava and Chini 2011) concludes that that the energy used in extraction, manufacturing, transportation, and installation of building components will play a more significant role in construction of energy efficient buildings. Also that the contractors play a major role in development of energy efficient means and methods to reduce energy consumption, hence carbon foot print during construction phase of the building. It is, therefore, proposed to raise a strategic and international research agenda on Energy Efficient Construction Management to be prepared for tomorrow’s challenge of making construction even more sustainable. CONCLUSION

By means of looking at historical trends in industrialization of construction process, and recent movements in the sustainable construction agenda, the purpose of this paper was to discuss and propose a new strategic research agenda focusing on Energy Efficient Construction Management. If the society for real wants to have zero, low, or passive energy houses a shift in research focus toward Embodied Energy is needed. Several obvious focus areas in construction management could possibly have large impact on lowering embodied energy in construction. In relation to the proposed industrialization framework in Figure 2, these possible focus areas are all in the process/on-site quadrant. Transportation and logistics both to site and internal transportation on site carry out for a significant energy contribution of Embodied Energy. Waste in a broad sense covers both waste of materials and waste of

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resources. In both circumstances it will lead to a higher than needed energy use. Planning of the construction process is an overseen factor in making construction sustainable, and correct planning in a lean construction framework will reduce the amount of rework needed. Finally, modern methods of construction can provide solution for alternative methods and materials that requires less energy contribution. REFERENCES

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