4. 1. Abstract
The recent increase in the awareness of carbon emissions, global warming and environmental
footprint is exerting pressure on the construction industry to emphasize on the environmental impact
of the industry. A paradigm shift from the conventional objectives of cost, quality and time to a
broader view in terms of environmental sustainability is the need of the hour. This demands the
introduction of construction management strategies that can control and reduce environmental
impact, and at the same time those which ensure profit and customer satisfaction. „Lean‟ construction
is such a production based strategy that focuses on reducing all types of resource wastage and also
ensures reliability in the work flow of the construction processes.
This paper investigates the impact on environmental footprint due to the implementation of the „lean‟
principles to improve various construction processes like open foundation, piling, concreting works,
block work and structural steel work, observed at different sites in India. Value stream mapping tool
was used to diagnose the wastes defined by „lean‟ literature, for the various activities. The study
showed that if these wastes were targeted under the „lean‟ perspective then the carbon emissions
could be reduced to a considerable extent. By implementing „lean‟ concepts in the process, for a
Piling and Open foundation activity a reduction of 16% and 26% of carbon emissions was possible.
Similar was the case with concreting activity (13%) and block work activity (18%). The paper thus
emphasizes on the need of better construction practices like „lean‟ to make construction „green‟.
2. Introduction
Construction industry is making significant contribution to the economic development but, the process
of construction and building operation is directly or indirectly leading to depletion of natural resources,
increased emissions, high energy consumption, degradation of the ecosystem and unpredictable
climate change.( Kibert, 1998, Hendrickson & Horvath, 2000; Horvath, 2004). For example, building
construction and operation accounts for 40% of the materials and 33% of the energy used in the
world economy (Rees, 1999). The construction industry should take considerable effort in reducing
the impact on environment by improving the environmental performances of the buildings and
infrastructure.
Major focus of studies in the area of environmental sustainability of buildings has been concentrated
around the building‟s operation phase (USGBC, 2005; Kibert, 2007; Jensen & Kouba, 2007); while
the other phases are given inferior attention. Even the „Green‟ rating systems like LEED (Leadership
in Energy and Environmental Design), and GRIHA (Green Rating for Integrated Habitat Assessment)
the on-site factors like carbon emissions from equipments, transport etc. are not given critical
attention. It is essential that, for a project to be called „environmentally sustainable‟ efforts should be
taken to enhance its environmental performance while designing, during construction, operation and
finally when demolition or rehabilitation becomes necessary.
Numerous studies have been conducted to develop process and technology innovations and
alternative low carbon materials, to achieve better environmental performances. However, it should
be noted that the non-technical issues should not be overlooked when reducing carbon emissions, i.e.
the improvement at the managerial level (Wu Peng and Low Sui Pheng, 2011). Hence focus should
shift to adapt strategies which can balance both the technical and non-technical improvements
required in the construction process. „Lean‟ production system could be a probable strategy in this
background, as it talks in terms of waste minimization and improving work flow reliability. This
research is therefore aimed to highlight the relevance of „lean‟ culture in construction and understand
how it can yield „green‟ benefits. It should be noted that „Green‟ in this paper refers primarily to
reduction in the carbon emissions due to on-site operations like from improper use of equipments.
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5. 3. Lean Construction
Traditional construction practices focused mainly on three major parameters cost, quality and time
while modern design and construction additionally concentrates on minimization of resource
depletion, minimization of environmental degradation, and creating a healthy built environment (Kibert
1994). A paradigm shift of this nature calls for a change in the prevailing culture of the construction
industry so as to promote infrastructure that is reliable, sustainable, and economical and serves its
ultimate purpose.
„Lean‟ construction‟ presents itself as a revolutionary philosophy, extracted from the manufacturing
industry, which underwent huge reforms on introduction of Toyota‟s „Lean‟ production management
systems. „Lean‟ philosophy brought out the concept of conversion activities (value-adding) and flow
activities (non-value adding). While traditional management improvement did not give due concern to
non-value adding activities, „lean‟ strategy treated conversion and flow activities separately.
Conversion activities are to be improved while flow activities are to be eliminated.
The Toyota Production system is the birthplace of „Lean‟. Engineer Taiichi Ohno was the architect in
formulating the „Lean‟ philosophy which focused on minimization of all types of wastes. Lauri Koskela
proposed the Transformation-flow-value understanding of construction (Koskela, 1999) in the
background of the established manufacturing theories of „lean‟. He explained the framework in which
„lean‟ production system could be applied to construction. The goal was to take the basic „lean‟
motives such as elimination of waste, cycle time reduction, variability reduction; pull driven production
control, continuous flow and continuous improvement, as foundation stones and developing
methodologies and applications in the context of construction.
The „Lean‟ Project Delivery System (LPDS) is a product of the „lean‟ construction institute founded by
Howell and Ballard to develop a leaner way to design and build capital facilities (Ballard 2000). The
„Lean‟ Construction Institute (2004) defines the term „Lean‟ construction as: „Lean‟ Construction is a
production management-based approach to project delivery -- a new way to design and build capital
facilities.
The simple ideology of „Lean‟ construction is to give customers what they want and at the specified
time and with minimum wastage of resources. „Lean‟ is not a methodology or tool that can be used for
improving performance; it is a philosophy to be inculcated into a process to promote reliability down
the line to the final construction product. It ultimately promotes speedy and reliable construction with
reduced wastes along with overall profit and competiveness. Where current project management
views a project as the combination of activities, lean thinking views the entire project in production
system terms, that is, as if the project were one large operation. To understand the potential „lean‟
thinking in addressing environmental problems it is essential to understand the core principles of
„lean‟ in which are briefly described in the context of construction as follows.
Value: - The first step in „Lean‟ implementation is to understand how „value‟ is perceived from the
customer‟s view point. In construction it means identifying the tasks which add „value‟ to the final
constructed facility. Everything that does not add „value‟ is to be considered a waste. For e.g.:-
Idle labour, machines, rework, waiting for instructions etc. Thus it is essential to derive a „value
stream‟ for the entire construction process which involves identifying and integrating the
processes that deliver „value‟. The focus should be on identifying the proper „value stream‟ and
targeting the non-value adding tasks so that cycle times can be reduced and efficiency can be
improved.
Flow: - One of the prime objectives of „Lean‟ is to make „value‟ flow, by eliminating the obstacles
which hinder the smooth conduct of the tasks. Koskela (2000) states that “Creating continuous
flow in construction is a huge challenge due to its fragmented nature, low standardization patterns
of activities and uniqueness of construction projects”.
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6. Pull Mechanism: - The principle highlights on the necessity to produce only what is wanted,
when it is wanted. This contradicts the conventional approach maximizing individual productivities
to achieve results. The downstream demand should trigger the upstream working as per „Lean‟
theory.
Perfection:- Quality improvement programs have progressively become integral aspects of the
construction industry. Results of this strategy are that reasonable improvements and
standardization of tasks have been achieved (Flavio and Granja, 1999). „Lean‟ thinking focuses
on pursuing perfection through a continuous improvement process thus restructuring the process
continuously so as to improve performance.
Suitable changes and modifications have to be made in the „Lean‟ theory principles developed by
Toyota to allow its better application in construction scenario because of the uniqueness of the
industry‟s products. Implementation of „Lean‟ is a simple two-step process namely: - Finding waste
and eliminating it. SECBE (2008) estimated that 30-40% of construction activity did not add „value‟ for
the customer. Examples include waiting for information and materials, reworking due to defects,
double handling of materials, unnecessary movements around site due to poor site layout and access
arrangements etc. There is evidence in the literature and industry practice that waste reduction is
achieved through „Lean‟ implementations, in particular material waste (Womack and Jones 1996;
Salem and Zimmer 2005; Nahmens 2007; Nahmens and Mullens 2009).
Taicchi Ohno (1998) categorized the non-value adding activities or „waste‟ in production systems into
seven categories as listed below. These categories are suitably defined in the context of construction
as follows. The possible environmental impacts of these wastes are also briefed.
Waiting Waste: -It results from periods of inactivity due to incomplete or delayed preceding
activities. For e.g.:-Mobilization delays, equipment waiting etc. resulting in increased cycle times,
energy wastage due to unnecessary working of machine/equipment , spoilage or damage of
materials (Concrete, pile bore etc.).
Motion waste: -When there is problem in the process layout, defects and excess inventory etc.,
extra steps have to be taken to mitigate these inefficiencies which are termed as motion waste.
This leads to doing tasks which add no „value‟ but increase the duration and Increased energy
consumption and emissions. It might also lead to damage and spill due to excess movement
Over-processing waste: - This refers to unnecessary tasks carried out in the construction
process with a view of adding „value‟ to the process but actually leads to excess costs and
increase in cycle time. It includes double-checking, double handling, reprocessing etc. More
materials consumed than necessary and also leads to excess energy consumption, emissions
and material wastage
Over Production waste: - Such waste occurs because of producing more than what is needed,
faster than needed or before it is needed when ideally the tasks should have stopped. This leads
to incurring excess costs, excess inventory, storage and maintenance problems. It leads to
wastage of materials and energy in making unnecessary products.
Transportation wastes: - As termed it means, wastes due to excess transportation of man,
material or machines due to improper planning of job or poor logistics at the site. It should be
given due attention because it leads to increased cycle time with no „value‟ adding activity being
performed; excess costs are incurred and materials are exposed to handling damages. It also
contributes to excess energy consumption and emissions.
Inventory waste: - Waste of storage space, material damage and accumulated monetary loss
occurring due to stocking of materials or equipment in excess than required or when there is low
a demand/usage. Inventory demands extra energy consumed in creating suitable storage
conditions and space for different materials.
Defects/Rework waste: - Waste of time and material occurring due to flaws in the construction
which needs to be rectified. It occurs mainly with design changes, poorly skilled labour, work not
conforming the quality standards or specifications etc. Rework leads to further consumption of
energy and materials and unwanted emissions.
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7. Most of the wasteful practices can be reduced by changing managerial practices while design,
procurement and production stages. Most of the wastes can be eliminated with proper planning and
control of the construction activities.
Though „lean‟ philosophy leads to the improvement of the efficiency and reliability of construction, it is
important that it does not impact the environment negatively. „Lean‟ considers the aspect of waste
reduction which also is a goal of „green‟ construction but, it is necessary to investigate if it burdens the
environment by any other aspect. This study thus focuses on analyzing possible linkages between
„lean‟ and „green‟ philosophies and to establish if by being „lean‟ can we be „green‟ too.
4. ‘Lean’ and ‘Green’ relationship
Green Building, also known as Sustainable Building, is the practice of creating structures and using
processes that are environmentally responsible and resource-efficient (U.S Environmental Protection
agency). As per emission statistics in UK and USA about 80-90% carbon emissions is said to be from
the building operation phase while remaining is contributed by the raw material, on-site construction,
and demolition or recycling phases of the building‟s life cycle. Some existing research have thus
assumed that the impacts of the „construction phase‟ on the environment are negligible (Horvath et al.
2003), while others have indicated that the environmental impacts associated with on-site
construction processes are underestimated (Hendrickson2000). This is due to the lack of well-defined
„green‟ construction practices and lack of metrics to collect accurate construction data and measure
environmental sustainability. Process-specific quantification of resource and environmental impacts of
on-site construction processes is essential to understand and improve the environmental performance
in the construction phase.
Since „Lean‟ is a philosophy originated from manufacturing environment, it is essential to track down
the relationship of „Lean‟ and the environment from the production platform itself. In the manufacturing
context, it was found that by adopting the aspects of „Lean‟ production philosophy and that of
environmental management systems they could achieve reduced pollution and increased efficiency
(King 2001, Hart et al., 1999, Gandhi et al., 2006). The EPA (2003) proposes that „Lean‟ provides a
platform that is highly focused on waste minimization and pollution prevention in an operational
environment, and hence provides an excellent foundation for environmental management tools such
as life cycle assessment and design for environment.
Riley et al. (2004) stated that, the greatest barrier to the construction of „Green‟ buildings in a large
scale was the higher initial costs, which were largely due to the learning curve of workers in building
with complex technologies and using unfamiliar materials, large design iterations, plus the added cost
resulting from immature construction processes. Isabelina and Laura (2011) suggest that the
introduction of „Lean‟ construction could solve these problems as; it provides a more structured job-
plan into which the „Green‟ objectives can be easily incorporated. Nahmens (2009) stated that it was
a natural extension to apply the „lean‟ concept to achieve „green‟ production and construction.
Wu Peng and Pheng, (2011) studied whether „lean‟ production philosophy is applicable in precast
concrete factories to achieve sustainability They found that for a precast concrete column
construction, an amount of 8.3% carbon emissions was reduced when the „lean‟ production
philosophy was adopted in the casting yard. They suggested that the evaluation of the „lean‟ concept
in achieving environmental sustainability could only be examined when environmental sustainability
was set at the target at the very start. The contribution of the „lean‟ concept to „green‟ could not be
fully assessed when reducing initial costs and eliminating waste were set at the targets.
Koskela,(1998) suggested that the principles of „lean‟ construction should converge to the
sustainability objectives in the form that „Eliminating „waste‟‟ should mean minimization of resource
depletion, minimization of pollution and, adding „Value to the Customer‟ should mean business and
environmental excellence.
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8. Wang and Guiyou (2011) highlighted that in the aspect of cost management, the nature of the „Lean‟
construction is to eliminate waste, which will change or eliminate the invalid time and outputs and thus
deliver projects without increasing cost. They concluded that the theory of „Lean‟ construction was
already offering the conceptual basis, and potential for novel methods and tools for sustainable
construction.
Though literature shows that „lean‟ has the potential to incorporate „green‟ objectives into its strategic
plan, it does not show precise and direct linkages between the two concepts. Researchers also argue
that „lean‟ might demand excess and sophisticated technology which might not cater to the „green‟
objectives. A study is thus necessary establish a direct linkage between the wastes defined by the
„lean‟ theory and the quantum of impact their reduction/elimination has on the emissions.
5. Research Methodology
The methodology followed for the research is summarized as follows
Different construction activities at sites and at different stages of construction were identified.
„Lean‟ value stream map was used as the tool to diagnose the wastes in construction activities
Current state maps of different activties were drawn.
Equipment emission data was collected and material wastage if any was noted.The energy
consumed in the process was converted to carbon dioxide equivalent values.
In each process the sub-activites were categorised to value adding and non-value adding.The
non-value adding activities were targetted and eliminated/reduced
A future State Map was proposed for the activities by trying to eliminate all the possible wastes in
the process as defined by „lean philosophy and the results were validated
Carbon emissions were recalculated based on the new future state map to identify considerable
changes, if any, due to reduction in cycle time in the future state map.
For the purpose of this study four construction sites were selected from which six individual activities
were chosen to obtain qualitative and quantitative data (Table 1). Qualitative data was obtained
through activity observation and semi-structured interviews with the engineers. Quantitative data
related to energy use of equipments was obtained from P&M department. The activities were chosen
in such a manner that they would act as a representative of an entire construction project i.e. from
initial piling or foundation stage through structural concreting works and some finishing works. The
author intends to present these activities not from an individual perspective but as though it
represents all the major stages of a project i.e. foundation, structure and finishing works.
Table 1:-Activities studied
TYPE ACTIVITIES CHOSEN FOR STUDY
SITE 1 IT Building Piling activities.
SITE 2 IT Building Concreting activity and Block work activity
SITE 3 Residential Concreting activity
SITE 4 Metro rail station Open foundation and Concreting activity
Studies suggest that VSM is one of the best visual tools that clearly depict information and material
flow in a process. It has generally been used to assess the cycle time, lead time, and inventory levels
etc. to define value and waste, since these are the key focus areas of „lean‟. VSM increases the
transparency and predictability of construction processes and hence helps people to have a thorough
understanding of processes. This tool can be made more useful by adding environmental impact data
to it. Symbols can be used to denote the emissions and other environmental hazards.
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9. For each activity, a current state map was drawn which showed the cycle time, inventory and also
depicted the wastes in the process. The aim was to attack these problems found in the process and
to reduce/mitigate them. Symbols are used to denote the processes, flow, inventory etc. A timeline is
shown below which indicated the time flow at each point of the process. The current state map of an
open foundation activity at Site 4 is shown in Figure 1. along with the proposed improvements.
Figure 1: Current state map and proposed improvements of an Open foundation activity at Site
4
A future state map is now drawn incorporating all the measures taken to improve the process. The
future state maps represent a better way in which the work could be done and in lesser time. The
proposed future state maps should be validated preferably by actual on-site implementation or by
using simulation software‟s. Figure 2 shows the future state map of the open foundation activity.
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10. Figure 2:- Future state map of open foundation activity at Site 4
After the current state map is derived, the carbon footprint calculation of the process in the
perspective of equipment emissions is done. Measurement of carbon emissions is one way to
understand and improve the environmental performance of onsite construction processes. The
energy consumption of all the equipments used in a particular process is considered for carbon
emission calculation. The energy consumed in liters of fuel or kilo watt hour of electricity is then
converted in terms of Kilograms of CO2 to get the emissions. The conversion values used in this
study is based on the National Atmospheric Emissions Inventory UK (2003).
Recalculation of this footprint is done as per the proposed future state map. The difference shows the
percentage reduction in emissions by following a better and reliable process after eliminating all the
„lean‟ wastes identified. Due to the limitation in the time frame of the study, in this study only
construction equipment emissions are considered for carbon footprint calculation. Material embodied
energy or energy consumption of small electrical appliances like bulbs etc. are not considered. The
energy consumption of the equipments are calculated and converted to kg CO2 equivalent using the
conversion factors. Only countries like US and UK have specific conversion factors to find out the
KgCO2 value, but they are considered as standard values because they represent the values based
on burning of one unit of the fuel. The activities considered are briefed as follows. Current and future
maps for all the activities could not be shown in the paper due to limitation in space and hence
readers are requested to follow the representative example in figures 1 and 2.
6. Foundation activity
Piling Activity:- The installation or construction of pile foundations is generally associated with
numerous problems. The current state map of the piling activity observed showed that mobilization
delays and poor site logistics were the main issues. Initial errors in surveying caused delays and
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11. alignment problems. Also the ground over which pile rig was placed was not leveled leading to
stability issues. Another major delay was due to the improper planning for the bentonite flow, which
requires bunds to be made so that the bentonite can overflow away back to the tank. The poor
logistics also effected the transport time of concrete and steel to the pile location. Concrete supply
was interrupted frequently owing to the frequent technical problems in the concrete batching plant
leading to stoppage of work. This delay caused further difficulties in the removing the casing from the
pile. Most of these problems could be addressed by proper planning and control of the activity.
The main objective of the current state map is to understand the problems or „wastes‟ in a process.
The seven wastes defined by „lean‟ literature were looked upon. The various sub-activities observed
were categorized into value-adding and non-value adding as per the „lean‟ principles. The non- value
adding activities were further divided to two categories:- Type 1 and Type 2 muda. Type 1 muda
means those which are necessary for the process but do not add any direct value to the final
product/output. They cannot be eliminated but can be modified to reduce the cycle time. Type 2 can
actually be eliminated or is not required in the process but is still performed. Most of the sub-activities
found as wastes were those which were required for the process but were not judiciously planned and
executed. The study focused primarily on the wastes which caused unnecessary emissions, like delay
in emptying of concrete trucks, idle operation of equipments, excess transport emissions due to poor
logistics, and delay due to poor planning. It should be noted that the equipments should work to add
value to a process and working more than what is required leads to wasteful emissions.
In the piling activity it was observed that by ensuring proper logistics at site and better site planning
the cycle time per pile could be reduced from 4.15 hours to 2.8 hours. This resulted in a
corresponding reduction in the carbon footprint by16%. This was mainly due to improvement in terms
of a properly prepared ground surface and better logistics for movement and better planning and
monitoring of works, which permitted smooth flow of work and lesser environmental impact.
Open Foundations:- In Open foundation activity at Site 4 about five foundation works were observed
and the major problem was the site traffic management because of the congested location. Getting
better productivity from the excavator was also a major challenge. Concrete trucks queued at the site
creating further problems. Improper labor mobilization and poor quality were other pinching problems
found in the site. Following Just-in-time concrete delivery and logistics plan approach in the „lean‟
perspective could bring down the cycle time from 26 hours to 23 hours for each footing. This resulted
in a reduction of carbon emissions by about 26%. Such constructions should give key attention to
ensure proper site planning prior to commencement of work (Refer Figure 1 and 2 for current state
and future state maps)
7. Structural Concreting activities
Concreting activities observed showed that the major problem is the interruption of concrete supply or
excess waiting at the point of delivery. In the concreting activity at site 2, reduction of cycle time of
concrete work from 23 hours to 17 hours reduced the overall emissions by about 13%. Better
mobilization and planning of concrete activity can thus lead to positive impact on the carbon footprint.
The reduction mainly comes about by eliminating idling of the miller at the location and promoting
more just-in time delivery.
In the concreting activity at Site 3, reduction of cycle time from 22 to 18 hours showed a decrease of
only 3% in carbon emissions. This is because the process was already quite efficient except for a few
logistics problems. By mitigating them the process becomes more efficient and greener.
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12. 8. Finishing activities
Block work: - The current state map of the block work activity at site 2 showed that, the major „lean‟
perspective problems were inventory at the ground and deficiency or waiting for blocks at the top
floor. Meeting the demand of blocks called for an alternative or parallel mechanism to transfer the
blocks. A management solution could not solve the problem and hence a more technical approach
that proposed the use of a crane to minimize the „lean‟ wastes of inventory and waiting was
suggested. This had a positive effect on both the cycle time as well as the carbon footprint. The cycle
time per cycle (45 blocks transport and placing is one cycle) reduced by 60 minutes. Overall cycle
time for the whole activity reduced from 12 hours to 10 hours. So from the „lean‟ perspective using a
crane is justified because it promotes flow of work. Here focus was on the equipment used to transfer
the blocks i.e. a crane has to work only 10 hours while the hoist will have to work 20 hours to
transport same number of blocks. In this case it was observed that using a crane yielded lower
carbon emissions (18% lower) than when the hoist was use. But if we consider the cost and footprint
associated with mobilizing a crane for the activity it is very clear that it is not a „green‟ option. But in a
situation where a crane is available for use at site and if it can be applied for the activity, it serves the
„Lean‟ and „green‟ purpose. However a contradictory finding here was that the „per hour carbon
emissions‟ of a crane is much larger (38%) than a hoist. So the number of working hours of the
equipment is the key factor to be considered here.
Structural steel Fabrication and erection: - Overall in the structural steel process the flow was well
maintained and the current state map reflected a „Lean‟ process. But the major issue was the non-
availability of civil work front for erecting the truss work. This caused inventory at site, damage during
storage and rework resulting in additional emissions due to rework. Observing the activity showed
that the work flow plan of the activity had to be improved. All the sub-activities were initially in the
same place in a line. But due to site restrictions, the work flow area had to be distributed and certain
sub-activities had to be shifted to different locations at site, which called for more transport. Mitigating
this transport waste could bring a reduction of 3% carbon emissions. It was also observed that the
material waste (Wastage due to cutting and grinding) could be reduced from 25% to 13% by using
properly customized steel sheets other than the standard market available sheets for work. In terms
of embodied energy, it reduces the carbon footprint by 22 % which is quite huge. This shows that
proper technical expertise of the activity as well as consideration of workflow can design a perfect
process.
9. Conclusion
Table 2:-Summary of Results
ACTIVITY Cycle Time Reduction Due To ‘Lean’ approach Reduction In Emissions
Piling (1 pile) 1.35 hours 16%
Open foundation (1 foundation) 3 hours 26%
Concreting of slab at site 2 (360cum) 6 hours 13%
Concreting of slab at site 3 (500 cum) 4 hours 3%
Block work (800 blocks working) 2 hours 18%
Structural steel fabrication(one truss) (In the order of days) 3%
Table 2 summarizes the results obtained for each activity observed. From the study it was observed
that concreting activities had a major impact on the carbon footprint. Activities which involved
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13. concrete delivery on site showed larger footprints owing to the large amount of transportation of
millers. It is difficult to generalize that a certain stage of construction or activity has a larger
environmental impact than others. But it is clearly observed that the transportation at site has the
largest and most direct impact on the environmental footprint. This is because; most of the
construction equipments are used for hauling or shifting purposes. Reducing unnecessary movement
at site should be a focus area. Inventory has the lowest impact in the perspective of equipments of
machines because; machines when idle don‟t create any emissions. „Waiting‟ wastes implies to when
equipments like concrete trucks are kept waiting at the concrete delivery points without unloading.
This is mainly because of improper planning and mobilization of the works. The equipment in-charge
and site engineers should ensure that the equipments are used judiciously and site preparations for a
work are done before the start of the work,
„Lean‟ and „Green‟ can be concluded to have a direct and positive linkage. This linkage can be
understood clearly from the study because carbon footprint calculation acts as the measurable
quantity of this linkage. Reduction in carbon emissions as a process becomes „lean‟er shows that the
strategies are strongly correlated. Other than implementing costly technical improvements and
innovations to achieve sustainability, the application of the „lean‟ production concept which includes a
series of management practices that do not involve high investment costs, will help to achieve better
performance and environmental sustainability. „Green‟ design and „green‟ products are not just
enough to make construction eco-friendly; the facility should be delivered in a „green‟ manner. Better
construction should be the focus of the time and „lean‟ provides a firm platform for the same.
Future study in the area linking „lean‟ and „green‟ could be focused on finding the impact of various
„lean‟ tools on the environment. Considering the effect of „lean‟ on „sustainability‟ i.e. not just
environmental aspect but the economic and social aspect, would be a promising research. This study
only considers equipment emissions while a comprehensive study requires calculation of embodied
energy of materials and other minor tools as well and it will show a better picture of the „Lean‟ and
„Green‟ linkage.
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16. 11. Author’s Profile
I am a civil engineer by profession. I have completed my B-
Tech in Civil from M. A College of Engineering,
Kothamangalam, Cochin. I have done my M-tech in
Construction Technology and Management from IIT Madras.
Presently I am working as a Planning engineer at L&T
construction in an ongoing project at Gujarat. The paper is a
based on the one year research work done as part of my M-
tech project.
Email: ann.fra12@gmail.com
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