Lean construction - Revision history

Tkokotas at 12:20, 20 December 2018

2018-12-20T12:20:43Z

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			''Developed by Anton Badman''


	The construction industry is known for working in projects, and those projects are today complex, uncertain and quick (CUQ)<ref name="Koskela2002"> Koskela, L.; Howell, G.; Ballard, G.; Tommelein, I. (2002). ''Foundations of Lean Construction''. In Best, R. & de Valence, G. ''Design and Construction: Building in Value.'' Oxford, UK: Butterworth-Heinemann, pg 211-226 </ref>. The industry is also known for having lower productivity and higher wastes than other industries<ref name="Ahmed2011"> Ahmed, S. & Forbes, L. (2010) ''Modern Construction: Lean Project Delivery and Integrated Practices''. Boca Raton, USA: CRC Press </ref>. Lean construction thinking started in the middle of 1990 as a way to handle these CUQ-projects. Lean production is well known within manufacturing industries to increase productivity and reduce wastes, but the lean production thinking cannot directly be applied to the construction industry. The reason is that there is a list of factors that differentiates the construction industry from manufacturing industries, e.g. duration of projects, the nature (repetitive or one-of-a-kind), etc<ref name="Gao2014"> Gao, S. & Low, S. (2014). ''Lean Construction Management''. Singapore: Springer</ref>.		The construction industry is known for working in projects, and those projects are today complex, uncertain and quick (CUQ)<ref name="Koskela2002"> Koskela, L.; Howell, G.; Ballard, G.; Tommelein, I. (2002). ''Foundations of Lean Construction''. In Best, R. & de Valence, G. ''Design and Construction: Building in Value.'' Oxford, UK: Butterworth-Heinemann, pg 211-226 </ref>. The industry is also known for having lower productivity and higher wastes than other industries<ref name="Ahmed2011"> Ahmed, S. & Forbes, L. (2010) ''Modern Construction: Lean Project Delivery and Integrated Practices''. Boca Raton, USA: CRC Press </ref>. Lean construction thinking started in the middle of 1990 as a way to handle these CUQ-projects. Lean production is well known within manufacturing industries to increase productivity and reduce wastes, but the lean production thinking cannot directly be applied to the construction industry. The reason is that there is a list of factors that differentiates the construction industry from manufacturing industries, e.g. duration of projects, the nature (repetitive or one-of-a-kind), etc<ref name="Gao2014"> Gao, S. & Low, S. (2014). ''Lean Construction Management''. Singapore: Springer</ref>.

Bdmn: /* Last Planner System (LPS) */

2015-01-06T14:05:18Z

Last Planner System (LPS)

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	DOCTOR OF PHILOSOPHY)</ref>.		DOCTOR OF PHILOSOPHY)</ref>.
	# '''The weekly work plan (WWP):''' The weekly work plan provides detailed work plan for each phase. It is weekly updated and based on discussion between different disciplines depending on the complexity of the project. The WWP also includes planning buffer for future work<ref name="Ahmed2011"/>.		# '''The weekly work plan (WWP):''' The weekly work plan provides detailed work plan for each phase. It is weekly updated and based on discussion between different disciplines depending on the complexity of the project. The WWP also includes planning buffer for future work<ref name="Ahmed2011"/>.
	# '''A daily plan (If this is required):''' The daily plan is especially needed in more complex projects and fast moving projects where~~. The~~ daily plan is a more detailed version of the WWP and does not only plan the activities of the day but also time of the day<ref name="Ahmed2011"/>. The last planner is responsible for this highest level of planning. It can be the foreman or other professional. The daily/weekly planning schedule determines the next days specific work assignments. The reason with this production control is to shield production from upstream uncertainty and to avoid wastes. Percent Planned, Complete (PPC) is used to measure the weekly accomplishment and LPS uses weekly meetings to evaluate the performance and a root cause analysis is carried out to find the reasons for underperformance and improve the performance for upcoming weeks<ref name="Ahmed2011"/>.		# '''A daily plan (If this is required):''' The daily plan is especially needed in more complex projects and fast moving projects where the daily plan is a more detailed version of the WWP and does not only plan the activities of the day but also time of the day<ref name="Ahmed2011"/>. The last planner is responsible for this highest level of planning. It can be the foreman or other professional. The daily/weekly planning schedule determines the next days specific work assignments. The reason with this production control is to shield production from upstream uncertainty and to avoid wastes. Percent Planned, Complete (PPC) is used to measure the weekly accomplishment and LPS uses weekly meetings to evaluate the performance and a root cause analysis is carried out to find the reasons for underperformance and improve the performance for upcoming weeks<ref name="Ahmed2011"/>.

	Communication and collaboration between different disciplines is essential for the LPS since many different stakeholders are involved and affected by the scheduled assignments.		Communication and collaboration between different disciplines is essential for the LPS since many different stakeholders are involved and affected by the scheduled assignments.

Bdmn: /* Last Planner System (LPS) */

2014-11-28T15:27:14Z

Last Planner System (LPS)

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	The LPS is based on different levels of planning, see Figure 3. There are three to four levels of planning dependent of the projects requirements:		The LPS is based on different levels of planning, see Figure 3. There are three to four levels of planning dependent of the projects requirements:
	[[File:Last-planner-system.jpg\|450px\|thumb\|right\|'''Figure 3:''' The Last Planner System process flow. Based on a figure in Ballard 2000<ref name="Ballard2000a"/> ]]		[[File:Last-planner-system.jpg\|450px\|thumb\|right\|'''Figure 3:''' The Last Planner System process flow. Based on a figure in Ballard (2000)<ref name="Ballard2000a"/> ]]
	# '''The master pull schedule:''' An overview of the major phases in the project and the milestones for these phases. Traditional master schedules are often included in the contractor's bid and often optimistic in the timeframes<ref name="Ahmed2011"/>.		# '''The master pull schedule:''' An overview of the major phases in the project and the milestones for these phases. Traditional master schedules are often included in the contractor's bid and often optimistic in the timeframes<ref name="Ahmed2011"/>.
	# '''The look-ahead schedule:''' The look-ahead schedule is an update of the phase plan and it is used for work flow control. For typically construction tasks this spans around 6-8 weeks<ref name="Ahmed2011"/>. The look-ahead schedule is common in traditional construction practices but is more comprehensive in the LPS and serves several functions e.g. shape the sequence and rate of workflow, match the capacity with the work flow, detailed methods for work execution, break down master scheduled activities and update schedules of higher level<ref name="Ballard2000a">Ballard, G. (2000) ''The Last Planner System of Production Control''.Birmingham: The University of Birmingham (A thesis submitted to the Faculty of Engineering for the degree of		# '''The look-ahead schedule:''' The look-ahead schedule is an update of the phase plan and it is used for work flow control. For typically construction tasks this spans around 6-8 weeks<ref name="Ahmed2011"/>. The look-ahead schedule is common in traditional construction practices but is more comprehensive in the LPS and serves several functions e.g. shape the sequence and rate of workflow, match the capacity with the work flow, detailed methods for work execution, break down master scheduled activities and update schedules of higher level<ref name="Ballard2000a">Ballard, G. (2000) ''The Last Planner System of Production Control''.Birmingham: The University of Birmingham (A thesis submitted to the Faculty of Engineering for the degree of

Bdmn: /* Definitions of Lean Construction */

2014-11-28T15:22:08Z

Definitions of Lean Construction

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	Lean construction is derived from the success of lean thinking within manufacturing industries. There are two slightly different main interpretations of lean construction, see figure 1. The first interpretation, as mentioned above, is about the application of lean production methods to construction. The second interpretation, on the other hand, views lean production as inspiration to the development of a new theory-based methodology for the construction industry<ref name="Koskela2002" />.		Lean construction is derived from the success of lean thinking within manufacturing industries. There are two slightly different main interpretations of lean construction, see figure 1. The first interpretation, as mentioned above, is about the application of lean production methods to construction. The second interpretation, on the other hand, views lean production as inspiration to the development of a new theory-based methodology for the construction industry<ref name="Koskela2002" />.

	[[File:Lean-construction-interpretations.jpg\|450px\|thumb\|right\|'''Figure 1:''' The relationship between the two main interpretations of lean construction. The figure is based on a figure in <ref name="Gao2014"/>]]		[[File:Lean-construction-interpretations.jpg\|450px\|thumb\|right\|'''Figure 1:''' The relationship between the two main interpretations of lean construction. The figure is based on a figure in Gao & Low (2014)<ref name="Gao2014"/>.]]

	These two interpretations are shown in two different definitions of lean construction. The first definition is from Koskela et al. (2002, pg. 211): "Lean construction is a way to design production systems to minimize waste of materials, time, and effort in order to generate maximum possible amount of value." This definition shows that lean construction endeavors for the same goals as lean production, which corresponds to the first interpretation.		These two interpretations are shown in two different definitions of lean construction. The first definition is from Koskela et al. (2002, pg. 211): "Lean construction is a way to design production systems to minimize waste of materials, time, and effort in order to generate maximum possible amount of value." This definition shows that lean construction endeavors for the same goals as lean production, which corresponds to the first interpretation.

Bdmn: /* Definitions of Lean Construction */

2014-11-28T15:21:31Z

Definitions of Lean Construction

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	Lean construction is derived from the success of lean thinking within manufacturing industries. There are two slightly different main interpretations of lean construction, see figure 1. The first interpretation, as mentioned above, is about the application of lean production methods to construction. The second interpretation, on the other hand, views lean production as inspiration to the development of a new theory-based methodology for the construction industry<ref name="Koskela2002" />.		Lean construction is derived from the success of lean thinking within manufacturing industries. There are two slightly different main interpretations of lean construction, see figure 1. The first interpretation, as mentioned above, is about the application of lean production methods to construction. The second interpretation, on the other hand, views lean production as inspiration to the development of a new theory-based methodology for the construction industry<ref name="Koskela2002" />.

	[[File:Lean-construction-interpretations.jpg\|450px\|thumb\|right\|'''Figure 1:''' The relationship between the two main interpretations of lean construction]]		[[File:Lean-construction-interpretations.jpg\|450px\|thumb\|right\|'''Figure 1:''' The relationship between the two main interpretations of lean construction. The figure is based on a figure in <ref name="Gao2014"/>]]

	These two interpretations are shown in two different definitions of lean construction. The first definition is from Koskela et al. (2002, pg. 211): "Lean construction is a way to design production systems to minimize waste of materials, time, and effort in order to generate maximum possible amount of value." This definition shows that lean construction endeavors for the same goals as lean production, which corresponds to the first interpretation.		These two interpretations are shown in two different definitions of lean construction. The first definition is from Koskela et al. (2002, pg. 211): "Lean construction is a way to design production systems to minimize waste of materials, time, and effort in order to generate maximum possible amount of value." This definition shows that lean construction endeavors for the same goals as lean production, which corresponds to the first interpretation.

Bdmn: /* Lean Project Delivery System */

2014-11-28T15:20:28Z

Lean Project Delivery System

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	The Lean Project Delivery System (LPDS) is a trademark of the Lean Construction Institute developed in the beginning of 2000s of Glenn Ballard. Projects are defined in terms of phases. The LPDS points out the importance of the relationships between the phases and the involvement stakeholders in each phase <ref name="Koskela2002" />. The overlapping triangles in Figure 2 represent the five different phases; project definition, lean design, lean supply, lean assembly and use. There are two modules that are embedded in the five phases and extends through the whole project time; Product control and work structuring. A summary of the phases follows:		The Lean Project Delivery System (LPDS) is a trademark of the Lean Construction Institute developed in the beginning of 2000s of Glenn Ballard. Projects are defined in terms of phases. The LPDS points out the importance of the relationships between the phases and the involvement stakeholders in each phase <ref name="Koskela2002" />. The overlapping triangles in Figure 2 represent the five different phases; project definition, lean design, lean supply, lean assembly and use. There are two modules that are embedded in the five phases and extends through the whole project time; Product control and work structuring. A summary of the phases follows:

	*'''Project definition:''' The project definition phase includes three elements: purpose, design criteria, and design concept(s). The role of this first step is to align and find the customer and stockholder values and needs. All the elements in this first phase is influencing each other, so there is an importance of good communication between the stakeholders<ref name="Koskela2002" />. This phase should include representatives from all different stages in the facility's life cycle; from the production team that will design and build the facility to the end user and stakeholders <ref name="Ballard2000"> Ballard, G. (2000). ''Lean Project Delivery Systems.'' Lean Construction Institute white paper-8, (Revision 1) </ref>. This differs from other project definition phases which traditionally only includes the architect and the client<ref name="Koskela2002" />.		*'''Project definition:''' The project definition phase includes three elements: purpose, design criteria, and design concept(s). The role of this first step is to align and find the customer and stockholder values and needs. All the elements in this first phase is influencing each other, so there is an importance of good communication between the stakeholders<ref name="Koskela2002" />. This phase should include representatives from all different stages in the facility's life-cycle; from the production team that will design and build the facility to the end user and stakeholders <ref name="Ballard2000"> Ballard, G. (2000). ''Lean Project Delivery Systems.'' Lean Construction Institute white paper-8, (Revision 1) </ref>. This differs from other project definition phases which traditionally only includes the architect and the client<ref name="Koskela2002" />.

	*'''Lean design:''' The alignment of the elements in the project definition allows the start of the lean design phase. This phase includes the elements: design criteria(s), design process, and product design. The relationships between the elements are similar with the project definition in the sense that they are developed simultaneously and require good communication between stakeholders<ref name="Koskela2002" />. It is important that the project team is observant of opportunities to increase the value for the customer and expanding the purpose of the facility. If the project allows this opportunity, the project needs to go back to the project definition in order to update the purposes and design criteria<ref name="Ballard2000"/>. Traditional design phases have the tendency to narrow the design phase by focus on one single solution to early in the project with the opportunity for a faster design phase but the threat of rework. To lower the risks of rework, the lean design phase should be ended at the last responsible moment streamlining the work and supply chains<ref name="Koskela2002" /><ref name="Ballard2000"/>.		*'''Lean design:''' The alignment of the elements in the project definition allows the start of the lean design phase. This phase includes the elements: design criteria(s), design process, and product design. The relationships between the elements are similar with the project definition in the sense that they are developed simultaneously and require good communication between stakeholders<ref name="Koskela2002" />. It is important that the project team is observant of opportunities to increase the value for the customer and expanding the purpose of the facility. If the project allows this opportunity, the project needs to go back to the project definition in order to update the purposes and design criteria<ref name="Ballard2000"/>. Traditional design phases have the tendency to narrow the design phase by focus on one single solution to early in the project with the opportunity for a faster design phase but the threat of rework. To lower the risks of rework, the lean design phase should be ended at the last responsible moment streamlining the work and supply chains<ref name="Koskela2002" /><ref name="Ballard2000"/>.

Bdmn: /* LPDS summary */

2014-11-28T15:20:10Z

LPDS summary

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	==== LPDS summary ====		==== LPDS summary ====
	LPDS is designed and structured with principles and techniques in order to pursue the goals of the TFV model. Such techniques are e.g. involving stakeholders from the whole project life cycle earlier in the project, last responsible moment thinking to prevent reworks, aligning stakeholder interests to increase the end value for the customer and carefully plan buffers to make them more responsive and agile.		LPDS is designed and structured with principles and techniques in order to pursue the goals of the TFV model. Such techniques are e.g. involving stakeholders from the whole project life-cycle earlier in the project, last responsible moment thinking to prevent reworks, aligning stakeholder interests to increase the end value for the customer and carefully plan buffers to make them more responsive and agile.

	The table 2 below summarizes the Lean Project Delivery System by comparing it to a traditional delivery system.		The table 2 below summarizes the Lean Project Delivery System by comparing it to a traditional delivery system.

Bdmn: /* Definitions of Lean Construction */

2014-11-28T15:19:10Z

Definitions of Lean Construction

← Older revision		Revision as of 15:19, 28 November 2014
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	Lean construction is derived from the success of lean thinking within manufacturing industries. There are two slightly different main interpretations of lean construction, see figure 1. The first interpretation, as mentioned above, is about the application of lean production methods to construction. The second interpretation, on the other hand, views lean production as inspiration to the development of a new theory-based methodology for the construction industry<ref name="Koskela2002" />.		Lean construction is derived from the success of lean thinking within manufacturing industries. There are two slightly different main interpretations of lean construction, see figure 1. The first interpretation, as mentioned above, is about the application of lean production methods to construction. The second interpretation, on the other hand, views lean production as inspiration to the development of a new theory-based methodology for the construction industry<ref name="Koskela2002" />.

	[[File:Lean-construction-interpretations.jpg\|450px\|thumb\|right\|'''Figure 1:'''The relationship between the two main interpretations of lean construction]]		[[File:Lean-construction-interpretations.jpg\|450px\|thumb\|right\|'''Figure 1:''' The relationship between the two main interpretations of lean construction]]

	These two interpretations are shown in two different definitions of lean construction. The first definition is from Koskela et al. (2002, pg. 211): "Lean construction is a way to design production systems to minimize waste of materials, time, and effort in order to generate maximum possible amount of value." This definition shows that lean construction endeavors for the same goals as lean production, which corresponds to the first interpretation.		These two interpretations are shown in two different definitions of lean construction. The first definition is from Koskela et al. (2002, pg. 211): "Lean construction is a way to design production systems to minimize waste of materials, time, and effort in order to generate maximum possible amount of value." This definition shows that lean construction endeavors for the same goals as lean production, which corresponds to the first interpretation.

Bdmn: /* Definitions of Lean Construction */

2014-11-28T15:18:55Z

Definitions of Lean Construction

← Older revision		Revision as of 15:18, 28 November 2014
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	[[File:Lean-construction-interpretations.jpg\|450px\|thumb\|right\|'''Figure 1:'''The relationship between the two main interpretations of lean construction]]		[[File:Lean-construction-interpretations.jpg\|450px\|thumb\|right\|'''Figure 1:'''The relationship between the two main interpretations of lean construction]]

	These two interpretations are ~~showed~~ in two different definitions of lean construction. The first definition is from Koskela et al. (2002, pg. 211): "Lean construction is a way to design production systems to minimize waste of materials, time, and effort in order to generate maximum possible amount of value." This definition shows that lean construction endeavors for the same goals as lean production, which corresponds to the first interpretation.		These two interpretations are shown in two different definitions of lean construction. The first definition is from Koskela et al. (2002, pg. 211): "Lean construction is a way to design production systems to minimize waste of materials, time, and effort in order to generate maximum possible amount of value." This definition shows that lean construction endeavors for the same goals as lean production, which corresponds to the first interpretation.

	On the other hand, The Lean Construction Institute defines lean construction as: "Lean Design and Construction is a production management-based approach to project delivery /.../ Lean Construction extends from the objectives of a lean production system - maximize value and minimize waste - to specific techniques, and applies them in a new project delivery process." This shows that LCI's definition correspond to the first interpretation. It has the same objectives as lean production and applies the techniques into construction.		On the other hand, The Lean Construction Institute defines lean construction as: "Lean Design and Construction is a production management-based approach to project delivery /.../ Lean Construction extends from the objectives of a lean production system - maximize value and minimize waste - to specific techniques, and applies them in a new project delivery process." This shows that LCI's definition correspond to the first interpretation. It has the same objectives as lean production and applies the techniques into construction.

Bdmn: /* Definitions of Lean Construction */

2014-11-28T15:18:22Z

Definitions of Lean Construction

← Older revision		Revision as of 15:18, 28 November 2014
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	==Definitions of Lean Construction==		==Definitions of Lean Construction==
	Lean construction is derived from the success of lean thinking within manufacturing industries. There are two slightly different main interpretations of lean construction. The first interpretation, as mentioned above, is about the application of lean production methods to construction. The second interpretation, on the other hand, views lean production as inspiration to the development of a new theory-based methodology for the construction industry<ref name="Koskela2002" />.		Lean construction is derived from the success of lean thinking within manufacturing industries. There are two slightly different main interpretations of lean construction, see figure 1. The first interpretation, as mentioned above, is about the application of lean production methods to construction. The second interpretation, on the other hand, views lean production as inspiration to the development of a new theory-based methodology for the construction industry<ref name="Koskela2002" />.

	[[File:Lean-construction-interpretations.jpg\|450px\|thumb\|right\|The relationship between the two main interpretations of lean construction]]		[[File:Lean-construction-interpretations.jpg\|450px\|thumb\|right\|'''Figure 1:'''The relationship between the two main interpretations of lean construction]]

	These two interpretations are showed in two different definitions of lean construction. The first definition is from Koskela et al. (2002, pg. 211): "Lean construction is a way to design production systems to minimize waste of materials, time, and effort in order to generate maximum possible amount of value." This definition shows that lean construction endeavors for the same goals as lean production, which corresponds to the first interpretation.		These two interpretations are showed in two different definitions of lean construction. The first definition is from Koskela et al. (2002, pg. 211): "Lean construction is a way to design production systems to minimize waste of materials, time, and effort in order to generate maximum possible amount of value." This definition shows that lean construction endeavors for the same goals as lean production, which corresponds to the first interpretation.