Benefits Of Lean Construction Engineering Essay

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This report examines the history of Lean. It explains the early beginning of Lean and how it has developed as a planning tool. I also define what Lean with basic principles and gives further knowledge of how Lean is implemented in construction industry. Furthermore in my report you will find knowledge about Last Planner System and advantages of using that theory.

Toyota Production System, Value, Waste, Lean, Lean Construction, Last Planner System, Planning.

Introduction / Problem statement

As part of the final semester of the education as Bachelor of Architectural Technology and Construction Management I've written this dissertation. Before I started this education, I worked as a carpenter in Iceland. My interest to write about Lean has come from studying Constructing architect and working in the construction industry.

When I started my education in VIA University Collage I have been hearing about the term Lean, this has made me curious about what it is. According to my experience in Iceland, I have recognised a problem within the construction industry that facing the project without good or well implemented planning. With these problems in mind and with no good result, I found out that some tools or knowledge is needed to improve the building industry. That is why I turned to the most used theories that exists today, Lean thinking, as Lean have been very successful in planning. In my interest to learn Lean, I wanted to gain knowledge of what Lean is, and it´s magical features as well as planning ahead.

Research questions

I chose to write about Lean, to answer questions which were important for me to know:

What is the history of Lean?

What is Lean?

What is Lean in construction?

What is Last Planner system?

The Road to Lean

Toyota Production System (TPS)

Sakichi Toyoda (1867-1930) the founder of Toyota Industries is often mentioned as the father of Japanese industrial revolution, like Henry Ford with American industrial revolution. He invented many of weaving devices which were called automatic looms. The automatic loom is a machine that spins thread for cloth and weaves textiles automatically. In 1896, Sakichi Toyoda invented Japan's first self-powered loom called the "Toyoda Power Loom." Subsequently, he incorporated many revolutionary inventions into his looms, including the automatic stopping device, which automatically stopped the loom when a thread breakage was detected, the warp supply device, and the automatic shuttle changer. Then, in 1924, Sakichi invented the world's first automatic loom, called the "Type-G Toyoda Automatic Loom (with non-stop shuttle-change motion)" which could change shuttles without stopping operation. From his invention comes the words jido and jidoka which were later used in the Toyota production system (TPS). The term "jido" is applied to a machine with a built-in device for making decisions. Jidoka refers to "automation with a human touch," as contrasting to a machine that simply moves under the observing and direction of an operator. The loom stopped when a problem arose, no defective products were produced. This meant that a single operator could be put in charge of many looms, resulting in a great improvement in productivity.

Kiichiro Toyoda (1894-1952) son of Sakichi entered his father's company in 1920, after graduating from Tokyo Imperial University. In 1921 he visited the United States and England for several weeks to visit textile factories and observe production methods in the West. It was in America that he became convinced that the age of the automobile had arrived and it was his dream of building automobiles, which was already becoming everyday transport for ordinary people. Kiichiro went back to Europe and America in 1929 to study automobiles factories and manufacturing techniques. In 1933 he established an automobile department within Toyoda Auto Loom Company and started s serious study of how to build a car. He completed his first car in 1936 calling it the Model AA which was a good competitor for American and European cars, both in price and technology. Toyota Motor Corporation was established in 1937 with Kiichiro as president. For Kiichiro to be able to compete with automotive manufacturers in other countries meant having to work out high productivity and low cost. Inspired by his favourite book My Life and Work (Henry Ford) and study of Ford´s management and production system led him to discover the belt conveyor (first conveyor in Japan) system´s purpose and eventually to the idea of "just-in-time" method (Producing or delivering only the items that are needed by the next process when they are required and in the quantity needed). In 1950´s Toyota announced massive layoffs because of Japan´s recession; this led to their workers going on strike. To settle the strike Kiichiro Toyoda stepped down as president. Kiichiro died two years later.

After graduating as an engineer from the University of Tokyo in 1936 Eiji Toyoda (1913- ) joined the Toyoda Automatic Loom Works, he was Sakichi Toyoda´s nephew. When Kiichiro stepped down as president Eiji was promoted to Managing Director of the Toyoda Automotive Works of the manufacturing arm in 1950. Toyota Motor had been in the business of manufacturing cars for 13 years at this stage, and had produced just over 2,500 automobiles. Like his nephew Eiji Toyoda travelled to the United States to visit Ford´s Rouge River Plant in Michigan, in his first year as Managing Director, his main reason was to study the auto industry and return to Toyota with a report on American manufacturing methods. When studying production planning during their visit to Ford, Eiji Toyoda and his managers observed lots of equipment making large amounts of products that were stored in inventory, only to be later moved to another department where big equipment processed the product, and so on to the next step. They saw how these discrete process steps were based on large volumes, with interruptions between these steps causing large amounts of material to sit in inventory and wait. After touring the Ford Motor Company, Eiji returned to Japan with a desire to redesign the Toyoda Automotive Works plants. After exploring Ford Motor's U.S. facilities, Toyoda turned to the task of redesigning Toyota's plants to incorporate advanced techniques and machinery. Toyoda decided to adopt US automobile mass production methods but with a qualitative twist. He saw opportunities to improve the production system and therefore set the tone for eliminating wasted time, motion, processing, resources, and inventories. His vision evolved into what is now called "Lean Manufacturing." He learned a lot about the Ford Motor Company "suggestion system", and Eiji promoted the concept of "continuous improvement" ("Kaizen"- A Japanese term that means to continuously improve in incremental steps.).

Taiichi Ohno (1912-1990) who is considered to be the father of the Toyota Production System, which became Lean Manufacturing in the U.S. Taiichi Ohno was born in 1912 and graduated from Nagoya Technical High School. He joined Toyota in 1932, when Sakichi had passed away 2 years earlier, and for about twenty years worked his way up through the firm. Ohno was the assembly manager for Toyota and developed many improvements that eventually became the Toyota Production System. Ohno was transferred to Toyota Motor in 1943 to restructuring its manufacturing division. After the war, Kiichiro instructed Ohno to "catch up with America" within 3 years. Toyota was verging on bankruptcy during much of this period and could not afford major investments in new equipment or massive inventories. Like other managers of Toyota, Taiichi Ohno travelled to America in 1956 to look at American mass production methods, the knowledge he gained about Ford´s assembly line was useful to his idea of continuous flow process. On his way developing the TPS, Taiichi Ohno gave credit to two concepts: The first concept he referred to Henry Ford as described in the book "Today and Tomorrow" (1926), and the second concept he referred to the supermarket operations in the USA which Taiichi Ohno studied during his visit in 1956. The second provided the basis of a continuous supply of materials as the supermarket provided a continuous supply of merchandise on the store shelves. By doing so the supermarkets demonstrated the concept of the "pull system"(production is triggered by the customer, as opposed to a forecasted schedule. Supplier processes can only produce if given a signal by a customer process). He was also known to be "ruthless" in his desire to drive out waste (any activity that consumes resources but creates no value for the customer) from the production of Toyota company. The elimination of waste marked the start of the Toyota Production System and remains the basis from which it has evolved to this day. He also instituted a system of problem solving called "the five why's." Workers were taught to trace every error back to its ultimate cause, then to develop a fix so that it would never occur again. Ohno's career accelerated as a result of his success as Assembly Shop Manager and he became an executive Vice President in 1975. In the early 1980's, Ohno retired from Toyota and was president of Toyota. Taiicho Ohno died in Toyota City in 1990.

The term Lean did not come from Toyota them self but from American researchers, Daniel Roos, James P. Womack and Daniel T. Jones, all employee of International Motor Vehicle Program (IMVP) at Massachusetts Institute of Technology (MIT). They came to realize that Japanese auto industries were dominating the American auto industry. To understand why this was happening the three directors summed together a team to investigate and study American, European and Japanese auto industry. After five years of study the result was the revolutionary book the machine that changed the world. It is now over twenty years since the term "lean" was given its modern meaning by John Krafcik (who at that time was studying at MIT). John Krafcik proposed the term during a meeting "This new system needs less of everything to design and produce products economically at lower volumes with fewer errors. It's lean." Since then "Lean Production", "Lean Management", "Lean Thinking" and "Lean Construction" have been well established terms.

Lean construction as a concept emerged in the early 1990´s through a work that was performed at Stanford University in California. In this development, attempts were made to adapt the Japanese Lean production thinking into the construction process. Lauri Koskela who is considered the founder of Lean construction introduced his understanding of construction process in his paper in 1992(Application of the New Production Philosophy to Construction). Koskela presented a production management paradigm where production was speculated in three complementary ways, namely, as Transformation, as Flow, and as Value, also termed the TFV theory of production. This three-way view of production has led to the birth of Lean Construction as a discipline that considers the transformation-dominated contemporary construction management. The production theory for construction proposed by Koskela and the concept of production as a flow showed almost immediately its usefulness by practitioners rethinking the construction management methods and later the management principles. Since 1992 modification of the Lean production concept in the construction industry has been continuing by Koskela.

Alongside development of Lean construction is the Last Planner System which was introduced by Glenn Ballard in 1993. Since the start of the work on the Lean construction there have been two major influences in the development, one as mentioned before from Lauri Koskela, the other from is Glenn Ballard and Greg Howell´s Last Planner method of production control, which have been outstanding leaders in the Last planner system. The method is well known worldwide and is implemented within the Danish construction industry. Last Planner System development continues under the direction of the Lean Construction Institute Directors Professor Glenn Ballard and Greg Howell with support from users around the world.

Essence of Lean

The word Lean is a big word for explanation and there are many terms within Lean that exists. All of the terms have though the same principals and all of them seek there idea logy from TPS. Lean is constantly evolving and is achieving one of its principals, continuous improvement. There are many theories, principals and terms in Lean that I would like to explain what it is we must take a look at in the first step of Lean thinking, which is to understand value, with necessary activities and resources are to create value. First step is learning to see waste. If something does not directly add value, it is waste. If there is a way to do without it, it is waste.

There are many Japanese words in Lean and one the most important is the word "muda" and it´s the one you really must understand. It is a word that doesn´t give the impression to sound good and it is somewhat we should avoid to achieve and be in constant awareness of, because the word "muda" means waste. So the elimination of waste is the basic principle of Lean Thinking. Taiichi Ohno, the mastermind of the Toyota Production System was ruthless toward waste and he identified seven types of waste, and they have become known as the 7Ws.

The 7 Wastes:

Figure : Waste cycle

Overproduction - When Ohno the ruthless enemy of waste was identifying the 7 wastes he noticed that the most serious of them all was the overproduction, because it is a root of many problems and other wastes. In simple terms overproduction is making too much, too early "just-in-case". This causes a many of problems, by producing too much too early the manufacturer will have excess inventory which can lead a standstill production of the product. "The aim should be to make or do or serve exactly what is required, no more and no less, just in time and with perfect quality."8

Waiting - Is the second most important waste and it is connected with flow. Keeping a good flow to the costumer is what Lean prosper on, rather than keeping the workers busy. In a factory, any time that an item is seen to be not moving (or not having value added) is an indication of waste. Waiting is the enemy of smooth flow. Although it may be very difficult to reduce waiting to zero, the goal remains.8

Motion - Redundant motions for both workers and layout of company is probably next important waste. If workers have to make unnecessary movement and waste time on workstation by non-optimal layout, it ultimately affects the quality and customer. "These wastes are often repeated many, many times per day - sometimes without anyone noticing. In this regard 5S can be seen as the way to attack motion waste."8

Transporting - With this in mind, the customer does not want to pay for unnecessary transporting of goods. Therefore material movement is a waste. On the other hand this waste can never be zero, but over period of time this should be reduced as much as possible. Double material handling is a waste affecting production and quality. "The number of transport and material handling operations is directly proportional to the likelihood of damage and deterioration."8

Overprocessing - Is the fifth of Ohno´s waste philosophy and it deliberates to "using a hammer to crack a nut". To discuss this matter further we have to think also about to use a one big machine instead of using many smaller ones. If we have one big machine it leads us to run that machine constantly rather than using several smaller machines that will do the same work for us. It becomes more flexible for the operators to. By using one big machine can lead to "bottleneck" in the production. "Think "small is beautiful". Smaller machines avoid bottlenecks, improve flow lengths, perhaps are simpler, can be maintained at different times and may improve cash flow and keep up with technology."

Inventory - As mentioned here before overproduction is waste affect, bearing that in mind that will lead to excessive inventory which is also a waste factor. Even though by having no inventory is somewhat is hard to obtain. Therefore by having big inventory will lead to waste of space and will affect quality and productivity. "Note the three types of inventory: raw material, work in process, and end items."8

Defects - The last of Ohno´s waste is the waste of defect. Failure always cost money as it comes up to doing the same thing again, rework and delay is also a waste factor for producer. Even though defect is a waste it is something that workers can learn from and improve from, rather than seeing it as rework or poor management. In service, "zero defections" has become a powerful theme, recognising that the value of a retained customer increases with time.

To improve yourself in Lean Thinking is to identify and learning to see waste. Waste is in its simplest form, when something does not add value to the production. As eliminating waste is the heart of the Toyota Production System and the basic principle of Lean thinking it is therefore very important to recognise waste. As stated above the 7w´s was developed Ohno´s idea in the TPS, nevertheless as that system relies on continuous improvement there have been other kind of waste stated and are definitely more to come in the future.

Womack and Jones´ 5 principles of Lean

Lean assists to bring detail to a systems view of the cosmos by advancing managerial concern in the method of work and data flows through the system, especially where it flows freely and where there's possibly constrictions. This allows for us to focus advance efforts on those areas that will amend the all system and avert sub-optimal alterations.The common estimate of lean is attractively simple; it's that the organisation ought to act obsessional on the most efficient intends of acquiring value for their customers. An organisation applying lean will access this dispute by: implementing 5 basic lean principles; focusing on understanding waste and value in its work and; training staff who do and manage the work to act as improvement teams to

Figure : 5 steps of Lean

bring about change. Lean aligns the organization to deliver customer value and eliminate waste. Because Lean thinking is in continuous improvement and a huge term to grasp for a person who is learning Lean for the first time, it is very helpful to go through the application of the five lean principles, as it revealed in the book Lean Thinking, the 5 principles are:

â- Specify Value - "The critical starting point for Lean thinking is value. Value can only be defined by the ultimate customer. And it´s only meaningful when expressed in terms of a specific product (a good or a service, and often both at once) which meets the customer´s needs at a specific price at a specific time". Ultimately it's the customer which is creating value for the organisation, because it's the customer that is purchasing the merchandise from the manufacturer. From the purchasers viewpoint it's the manufacturer that is producing value for them. Lean thinking consequently must begin on a specified endeavour to accurately specify value in terms of particular merchandises with particular capabilities offered at specific prices through a negotiation with particular purchasers. The main subject for this principal is for the producer to think about value from the eyes of the customer.

â- Identify Value Stream - "The value stream is the set of all the specific actions required to bring a specific product is the set of all the specific actions required to bring a specific product (whether a good, a service, or, increasingly, a combination of the two) through the three critical management tasks of any business: problem-solving task, information management task, physical transformation task". To identify the value stream we need to think about the final outcome of the product and the path toward that outcome. This principal is about thinking about the system of activities to design, develop, and provide a particular good or service for the customer along with information, raw material and the flow of the product.

â- Improve the Flow - "Once value has been precisely specified, the value stream for a specific product fully mapped by the lean enterprise, and obviously wasteful steps eliminated, it´s time for the next step in lean thinking - a truly breath-taking one: Make the remaining, value - creating steps flow". Improving flow is to model and design the production system with product development, including fulfilment of order and to have the production properly organised. It ultimately leads to avoiding wasteful activities and material. As Henry Ford invented the conveyor belt, he was improving the flow and having it more continuous from raw material to the customer with well-designed production system at that time.

â- Pull - "In fact, it is because the ability to design, schedule, and make exactly what the customer wants just when the customer wants it means you can throw away the sales forecast and simply make what customers actually tell you they need. That is, you can let the customer pull the product from you as needed rather than pushing products, often unwanted, onto the customer." By having pull implemented in your production system you are therefore minimizing a change of overproduction and reducing inventory amendment. This is ideal and fits perfectly with the JIT in TPS, because the customer is pulling the product just-in-time from the organisation.

â- Pursue Perfection - "It dawns on those involved that there is no end to the process of reducing effort, time, space, cost, and mistakes while offering a product which is ever more nearly what the customer actually wants. Suddenly perfection, the fifth and final principle of lean thinking, doesn´t seems like a crazy idea." By specifying value, identifying value steam, improving flow, fulfilling pull, ultimately it leads to perfection for the organisation as these four steps are repeated a state of perfection is reached, eventually creating perfect value with no waste. As it leads to continuous improvement, this principal will deliver a product requirement for the customer with no inventory for the manufacturer.

These 5 simple principals introduced in Lean thinking by Womack and Jones, are a good steps to follow to reduce waste and maximise value, not only for the customer but also for the manufacturer. Even though these are basic principles to follow it is used within the Lean terms that have evolved out from Lean thinking, Lean production, Lean management and Lean construction have all the same main principles to implement.

Lean thinking introduces a number of terms and designations. In the following text some descriptions and explanations are given.

Kaizen - is the Japanese word for continuous improvement. As the main objective of Lean, Kaizen seeks to eliminate waste. Kaizen is not only used in manufacturing but also in healthcare, government, banking among other industries.

Kanban - a Japanese term for signalling device or system that gives instruction for production.

5S - is set of 5 Japanese words, seiri, seiton seiso, seiketsu and shitsuke. It is a list that teaches employees how work should be done.

Sorting - have only necessary tool within the working area.

Straightening - everything has its place and with clear labelling. Items arranged in a decent manner endorse better work flow.

Shining - have everything in the right place and clean the work area. With this rule it is easier for worker to know for sure where tools, materials or items are in the working area.

Standardizing - by having work standardized workers should know there responsibilities by following the first 3´Ss.

Sustaining - continue the same standard of work with the previous 4S´s in mind and think about new way of working.

Heijunka - Production levelling. Fluctuations in production increase waste, therefore it is best for the organisation to have the process implemented at constant and predictable rate.

Hansei - comes from Japanese culture and means to recognize your own mistake and initiate improvement.

Muda, Muri, and Mura - the three types of waste. Muda has previously been explained. Muri is overburden on the workers affecting his morale which can lead to undesirable manner. Mura stands for inconsistency in the production system, wide variety of workload is a waste as it can have effect on the workers.

Push - when manufacturer is producing a product without any demand from the customer thus creating inventory and other wastes.

5 whys - basically asking 5 times why which guides the inquirer to the root of the problem.

Poka-Yoke - a procedure to prevent defects and human error to occur.

Critical path - number of activities that are connected with each other, as the next activity cannot begin until the former step has been completed.

These fundamental theories are the main principals of Lean thinking. Never the less these fundamental principles and theories work within all other Lean concepts and are followed to instruct continuous improvement. On the basis of these above mentioned Lean theories there have been developed and elaborated further into the Lean systems. One branch of the Lean systems leads to development of the construction industry, given the name Lean construction, which will be researched in the following chapter.

Lean in construction


The construction industry has in the past been accused for bad performance in many factors; deadlines, cost, and rework amongst others as common methods can be inefficient and ineffective. It was therefore needed to rethink construction work. In 1992 the first workshop on Lean Construction was held and The International Group for Lean Construction (IGLC) was formed. Originally the Lean Construction was implemented from manufacturing. IGLC has since 1992 had annual meetings as it aims to improve theories in construction.

Lean manufacturing or Lean production where well established in books by Womack and Jones, The machine that changed the world and Lean thinking. When Lauri Koskela published a report in 1992 he wanted to implement these theories into construction. His objective was to improve performance in construction. Lean in construction seeks the main goals from Ohno´s TPS theory, "maximizing value by eliminating waste". To be able to understand construction as a production Koskela identified a concept, Transformation-Flow-Value or TPS-concept.

Figure : The TFV theory of production

Transformation - explains that production is understood as steps adding value for the product. As Transformation is considered as management tool and its findings leads us to the lowest price.

Flow - this approach seeks its concept all the way to Henry Ford's production system, and provides efficient flow of material just-in-time and eliminating non-value activities. Koskela´s vision of flow is activities of events linked together, inspection, transport and waiting.

Value - maximizes the final value for the end customer to meet his requirement in the best way.

The concept of TFV gives us more clear vision to the construction industry and opens up new approach to the process of construction and management in the industry. With Koskela´s concept it revels also the construction as a one-of-a-kind production as construction varies from project to project.


Lean thinking is develop standardize product in manufacturing, this is not the case for construction. The products in construction emphasises the unique production or in other words, one-of-a-kind production. As a one of a kind, construction implements a production in a rigid assembly structure, as operation cannot be substituted and most of the production takes place in the random and momentary situation of the construction site. It is therefore important to have good cooperation the customer and the team of production at the early phases. Good work in the early stages have to take in count detailed analysis of client´s needs and requirement for the project as it will therefore be easier to implement the customer need in construction phase. Subsequently as a result the construction phase will require less rework, delays and changes.

In resent construction development project are becoming more and more standardized. Manufacturing many of building components are implemented in the construction, such as structural steel and pre-fabricated concrete elements are becoming well known in building construction. Correspondingly the construction materials are turning more to components or systems with great amount of prefabrication, thus having the process at construction site more assembly process. The construction industry is corresponding to these needs by having modularized manufacturing system and having construction process complication reduced. Although this form of construction is becoming more common, the scheme of building production is still considered as a one-of-a-kind product.

Complex system

To fully understand a construction it has to be looked at from complexity perspective, when forming an effective management system for new project it can be complex to deal with organisation and operating the project. The construction project process is a form of procedures performed by workers and machines from the trade contractors taking part in the project. Nevertheless the trade contractors all work on other projects at the same time as well, making the most out of there resources thereby having well defined network within their area and acting as one construction group.

This network deals with activities within the company organisation, project managers tend to move the workers around projects and are likely to neglect the human factor. This movement of staff affects the workflow. Consequently if the workers are uncertain, the workflow begins to fluctuate which can lead to a waste for the project.


A dictionary definition of cooperation is: "the act of working or acting together to achieve a common goal". As we look at the construction as a complex process and one-of-a-kind project, cooperation is therefore needed to establish a good flow. Well-formed cooperation between all contractors of the construction project is necessary for all participants of the project to be able to achieve the same goal. "That things are bad may be hard to prove. But experiments with new forms of cooperation and a new management style almost immediately show a better performance through a more efficient process."


As Lean Construction pursues the principals from the TPS theory it also have come to realize how each construction project unique, therefore coming up with new concept was important for Lean Construction to improve. As a construction project is complex system and on-of-a-kind a well-constructed planning system was required for the process to have reliable work flow. "In construction work is released by an administrative act, planning. In this sense, construction is directives driven and so measuring and improving planning system performance is the key to improving work flow reliability." At the similar time as the idea of Lean Construction was developed an approach to planning was introduced by Glenn Ballard, the Last Planner System. It has become a useful tool in Lean Construction and produces reliability for the workflow of construction. In the upcoming chapter I will research this system further.

Want to ad more here f.x

Promise cycle and or


Last Planner System (LPS)

In 1992 Koskela presented a concept to understand construction as production. Further development in that area within Lean Construction, was developed a management tool for construction process. The Last Planner System of production control (LPS) was presented in 1992 and is used with connection to Lean Construction. LPS accentuates the connection between scheduling and production control and has become the most used as well as best developed tool within Lean Construction. The LPS invented by Ballard is set to improve productivity for the construction industry as it is a technique that shapes workflow and addresses project variability in construction. LPS is set to make production plan ready which is performed in workshops for continuous improvement, ultimately it will reduce time and cost alongside increase quality and safety.

Figure : Structure of Last Planner system

LPS is divided into four levels of planning with each level deliberating what should and can be done. In this way the planning of the project helps the planners to clarify problems and remove them from the project to achieve their goals, thus reducing waste and deliver value to the customer.

The master schedule is design and scheduled by designer and costumer. It should establish realistic work plan as it determines available time and displays execution strategies. Master plan must identify milestones that are important for the customer as well as other stakeholders with project objectives in mind. The master schedule should have as much detail as possible, as it seeks to identify relationship between tasks, areas of uncertainty and to increase that project objectives are achievable. Master schedule is important for project scheduling but is not designed to tell us how work will be done. The master plan demonstrates the critical path in the project but cannot be used as site management tool as it only clarifies simple sequence relationship between tasks.

Figure : LPS in Gantt chart

Phase scheduling (RPS) is then created according to the master schedule. As it uses a pull technique the reverse phase schedule, as it is often called, develops a schedule that works backwards from the milestones of the master schedule. This schedule is created by all of the last planner, client, main contractors, sub-contractors and suppliers. This second phase of planning demonstrates more reliability to the on how we are going to do the work and increase confidence upon if we can deliver the milestones. As the process becomes closer to the end of the schedule a clearer vision for duration of activities should be established and most of the undefined activities defined. The planners should also explore how the phase can react to early completions.

Look-ahead planning (SWLA) is often known as six-week look-ahead plan. When the phase schedule has clarified the important milestones a plan to look-ahead is formed to ensure the requirements for good workflow. As large activities are identified in the phase schedule the look-ahead schedule plans specifies the task in more detail to ensure requirements for the task and identify availability of workable backlog. Look-ahead plan implements the work that is supposed to be done in near future, usually 6 weeks before the work is supposed to be done.

The purpose of the look-ahead schedule is to:

Shape workflow in the best achievable sequence and rate for achieving project objectives that are within the power of organization at each point in time.

Match labour and related resources to work flow.

Produce and maintain a backlog of assignments for each frontline supervisor and crew, screened for constraints.

Group together work that is highly interdependent, so the work method can be planned for the whole operation.

Identify operations to be planned jointly by multiple trades.

Figure : Example of Look-ahead schedule

Develop detailed plans for how work is to be done considering safety, environmental, and quality issues.

Figure : Look-ahead process

Once tasks are applied in the look-ahead schedule they are magnified to more detail so the planner can screen activities to be ready at planned milestone date. Screening the activities the planner can determine if an activity can be made ready for the planned date based on activity restrictions, taking into consideration the possibility if a task can be implemented to the look-ahead plan. Subsequently activities are made ready by solving the restrictions before the actual construction so they ready for the weekly work plan. Lean look-ahead planning is the process to reduce uncertainty to achieve possible constraint free assignments.

Figure : Weekly work plan process

Weekly Work Plan (WWP) is made in co-operation with the Look-Ahead-Plan, it further elaborates the six week schedule in more detail. After the look-ahead plan clarifies the work that should be done by creating a workflow of activities with related resources and labour. Subsequently should is transformed into what can be done impending on foreseen circumstances. The uncertainty factor becomes clearer and increases communication between trades. As the last planners (Foremen) identifies the work that can be performed a schedule made for what they can do, resulting on that they give a commitment on what they will do. "Thus the certainty of workflow from one crew to the next is a key to improving project performance." As a weekly work plan is formed a mid-week meeting is held to report on the process of WWP, it gives ability to adjust and reform the schedule of ongoing week.

Figure : Weekly Planning Cycle

Figure 10: PPC assessment

As the weekly work plan have been made it is therefore necessary to review and reflect on whether or not an activity has been completed. Consequently a measuring tool is needed to calculate the performance. With the weekly work plan a schedule is made for activities that will be made the calculation tool, Percent Plan Complete (PPC) gives us outcome on how well will matches did. As a result, gives a percentage number on the process performance for the past week. Only yes or no answer is taken into account for this measuring system, only completed work is taken into consideration. For further understanding if work has not been completed a simple question has to be asked 5 times, why?-Thus being able to discover the root of the problem.

A work that is ready to be done but

Want to talk about

Workable backlog

Within the last planner system is also other On site techniques:

Increased visualization

First run studies - act/plan/do/check

5s process

Final words

Push vs. pull

Talk about promise cycle

Good definition on the guide at page 1

Summary of working process

This dissertation is based on analytical research methodology specially directed at my future within the building and Construction profession. I have looked at the problem of planning and reviewed Lean Construction that are commercially available and which claim to solve the problem. Lean Construction was analysed on the basis of eliminating waste and to maximize value, the results documented and final conclusions made.

I have been analysing existing facts and theories. My research is based on information from books and the World Wide Web. During my research I have picked up the relevant information that has increase my knowledge of Lean.


I have researched and documented many aspects of Lean thinking specially the tools and technique that is required to develop a construction process. I have also defined the main theories of Lean, starting from manufacturing down to the Last Planner system. My goal for this report was simple, to gain a better knowledge of Lean. Therefore I started with the beginning and the development of the Toyota Production System. As one of the main principals of that system, continuous improvement, I came to realize that this theory is continuously evolving, revealing new opportunities to project planning.

Lean Construction tends to produce good results which can only be an advantage to anyone managing a project. In effect Lean Construction is one of the best forms of delegation which can save companies both money and time.

When I start as a project manager, I will be able to see the importance of planning and communication of all participants within a project. I now know the principals of Lean process and will be prepared to implement that system into project planning.

I recommend all future project leaders to put time and effort to motivate their workers and implement the Last Planner System into their construction process. This can save the company from getting a bad working environment, which will cost them time and money by eliminating waste and maximizing value.