1.0 Chapter One – Introduction
This chapter begins with an introduction into the study background and the current housing situation that the U.K is facing. It will follow with the consideration for Lean implementation in the residential sector, supported by a research question and objectives to assist with this study.
The Current situation in the U.K.
After world war two, the UK used to build 300,000 new homes each year (Wheeler, 2015). However, as of recent years, this has not been the case as only half of these houses are being managed to be built as highlighted in figure 1 (Castella, 2015). Figure 1 gives a graphical representation of how the house building numbers has dropped over the recent years.
Figure 1: Demographics in the house throughout the years
Source: Castella (2015)
The U.K is current leading towards a serious a house building crisis. A decade ago, the Barker Review of Housing Supply (2004) noted that about 250,000 homes needed to be built every year to prevent spiraling house prices and a shortage of affordable homes. Castella (2015) further eludes to this point by which the target has been consistently missed. He also stated that in 2012 – 2013, the UK hit a post war extreme low of 135,500 homes, which was ultimately due to the financial crisis. In 2014, the figure recovered slightly to 141,000 homes, although the target required by labour specifically in 2007 had dropped by the coalition.
In May 2014, Mark Carney, governor of the Bank of England, complained that housebuilding in the UK was half that of his native Canada, despite the UK having a population twice the size. The consequences have been rocketing prices in London, the South East and some other parts of the country. (Elliott and Treanor, 2013)
As stated by Office for National Statistics (2013) a total of approximately 3.3 million 20-34-year-olds were still living with their parents in 2013, a record breaking number since the research began in 1996. This has not improved as a new report by Shelter in 2015 found the housing crisis was at its the lowest level in which a quarter of adults under the age of 35 were still living at home in their childhood bedroom (BT, 2016). Therefore, it is evident that an issue has arisen by the productivity and delivery of houses within the housing industry.
Wilson (2010) indicates that the failure of housing supply is having a number of wider economic and social implications. Due to improved life expectancy rates and a rise in the number of households with just one person, it is evident that this rising demand is not being met. The growing concern with housing supply not being met is becoming more of an issue for the modern society. The affordability of these houses also plays a factor. As seen by Hilber (2015) in the last 40 years, house price growth has grown dramatically and is increasing faster than ever. Moreover, Wolf (2015) further eludes on this point highlighting that the whole housing crisis is becoming a serious issue. This places importance on why there needs to be such study to review the tools and techniques used within the construction industry and other approaches that can be adopted to improve the residential sector.
Introduction of Lean
The efficiency of Lean that has been illustrated in the literature of manufacturing companies in Japan has lead Lean to become a popular tool (Womack, Jones & Roos, 1990, p. 188). “Mr. Taiichi Ihno and Mr. Kiichiro Toyoda” executives of Toyota are known to be the initial developers of Lean. They analysed the production system and were able to identify the different kinds of waste in the system (Black & Miller, 2008, p. 4). However, most recently, Lean has advanced into a more management approach that aims to improve all processes across the industry (Taleghani, 2010). Construction operations are substantial in the global economy because of growing need and demand for buildings (Frozen Food Digest, 2002; Bowen & Youngdahl, 1998). Employees productivity is improved by approximately 30% when Lean implemented, which then increases quality for the customer (The Staff of the Corporate Executive Board, 2010). Nevertheless, regardless of this fact, housing contractors are not offering quality houses to customers (Piercy & Rich, 2009).
Despite the growing awareness of the need for Lean implementation in the construction sector, few studies have examined its effectiveness to strengthen their financial position. Subsequently, there are not many books and journals about best practices on Lean in the construction industry, where organisations could learn before applying this tool (Sarkar, 2009). Hook et al. (2008) also highlighted that even though there are several studies for Lean in the housing sector, these studies do not have a strong base, and they significantly lack the analysis on the implementation process of Lean tools and techniques.
To fill this gap, this research study aims to explore and understand Lean implementation process in the construction sector with the emphasis on the residential sector. In this context, the research will contribute to understanding Lean tools and techniques, as well as the critical success factors (CSF’s) and challenges that are faced while implementing them.
Academic research on Lean is focused mainly on production and its impact on process improvement and a organisations performance; however, minimum on implementing Lean in the residential sector. Therefore, the following research question has been formulated:
“Can the implementation of Lean tools and techniques improve performance in the residential sector?”
Using this research question will allow a current understanding of Lean tools and techniques as well as the challenges and benefits of Lean implementation in the residential sector. The current tools and techniques will be discussed through the literature review. Furthermore, the support to answer this research question will be from data and analysis from individuals within the residential sector and those who have implemented Lean successfully on their own projects. This awareness, will create a more in depth understanding of the benefits that can be made through Lean.
To help understand and support the research question, there needed to be the identification of objectives to meet the overall end goal. The objectives were as followed:
Objective 1 – Summarising the current housing crisis being faced within the UK and the impact it has on the end user.
Objective 2 – Determining the current awareness and appreciation of Lean construction within the residential sector, while comparing to the traditional constructional approach.
Objective 3 – Investigating the current Leans tools being used in construction projects.
Objective 4 – Proposing Lean tools which can be used within residential projects.
Definitions of Main Concepts
To fully understand the goal of the research, there are key concepts which were established to ensure enough substance to the topic. The main concepts are defined below:
Lean Production: (Womack et al., 1990, p. 67), mention that this concept originated from the Toyota production line with the main objective of reduction in waste and utilisation of fewer resources than that of a mass production line. Furthermore, the Lean production aims to eliminate non value added activities by using reduced resources as stated by Emiliani (1998). Furthermore, Lean production was expanded by Kolberg et al (2006) in regards to the enhancing the shop floor techniques to all manufacturing functions by including and involving the whole organisation.
Lean Thinking: The main objective of this concept is to have minimal waste by working faster and more efficiently. It is created when organisations operate in thinking and listening culture, where process design is developed by workers who deliver products or services (Atkinson, 2004). For the effective development of Lean Thinking, success factors that are associated with this concept should be communicated effectively to organisations that implement it. Also, (Melton, 2005) mentions that waste identification should be carried out continuously, customer satisfaction should be focused on and process flow monitoring.
Lean Construction: The Lean construction concept results from the evolution of production management to construction. Key features of Lean construction include construction, concurrent design, clearly defined of objectives for the successful project delivery, the application of project control throughout the life cycle of the project from design to delivery and aims for customer satisfaction by maximising project performance (Aziz, 2013).
Waste: Any activity that doesn’t add value to the customer or end product is deemed to be waste. Waste is created due to the type of operational proccess that that are carried out in an oranisation. however, waste cannot be eradicated completely, but it can be reduced as mentioned by Emiliani (1998).
Value added activities: These are activities that are deemed to add value to the customer and which they are willing to pay for (George 2004, p. 28). They are activities that can not be performed without susbstantial finencial or time investment (Maleyeff, 2006). Kollberg et al. (2006) expressesthat these activites are only defined by the customer.
Non-value added activities: Customers are not wiling to pay for these activites as they do not generate any value for them, hence they should be erradicated (George, 2004, p. 28). Organisational processes are the reason why these activities exist (Maleyeff, 2006)
With a growing concern over the housing crisis, it is evident this area of study was current and a key focus to improve sustainability in the future. The aim was to explore the implementation of Lean to help improve the current housing circumstance. From conducting this research, it justifies the impact that Lean can have to solve current issues within the U.K.
This research was needed for academic reasoning as it needs to be clear whether the implementation of Lean can improve and enhance the current challenge that the U.K. is facing. The research enhances our understanding of how using different concepts and methods can lead to the better housing to balance out the number of prospective buyers. It also helps to identify knowledge gaps which will need more investigation regarding what is learned academically.
There was a need for this research for businesses, councils, housing societies to understand the benefits of using Lean construction. The current housing crisis puts the U.K in a sensitive place as there are several prospective buyers currently looking for homes. Without these houses being built, it has a downwards impact on the economy. Understanding the importance or effectiveness of using the Lean concept, can potentially improve the current housing situation as businesses can begin to adopt this approach moving forward.
Delimitations of study
This research focused on data that was collected from interviews carried out. It was identified that other factors affect the delivery of housing projects such as planning permissions periods, availability of land and political influences. This research was solely based on site construction of houses and how lead times and housing quality can be increased by the implementation of Lean. Secondary data was collected from previous cases studies that had been carried out from the participants as well as outlining the positive impact that Lean has had on other construction projects. These benefits will then be used to conclude the overall research question. This study aims to answer the main research question, rather than making generalisations with the implementation of the theoretical Lean techniques and tools in the residential sector.
Procedure and method of literature review
Various kinds of sources were utilised in the study, to understand the extent of available research on implementation of Lean in the housing sector and to gain familiarity with the research topic. The online library database from Oxford Brookes University provided research results from various articles and journals associated with Lean Construction. Some books that had information on the Lean construction and Lean manufacturing were reviewed to offer a better understanding of the Lean concept and a starting point to the study. Limited research on Lean construction in the residential sector online articles and practitioner reports were used to provide a strong foundation for the literature review.
From the literature review, key findings were identified by contrasting and comparing various point of views from authors. Numerous research papers on Lean were found, key words related to the study were used as filters to narrow the relevant papers to the study at the first stage. A selection of relevant papers to the study was used to carry out the literature review.
Research Focus – The cause of the housing crisis
The housing crisis is currently a huge problem within the U.K. This is based on the assumption on factors such as cost, immigration, and effectiveness of the resources being used within the UK. As suggested by May (2012), it was claimed that a third of all new housing demand in Britain was mainly caused by immigration. As the demand increases, it is expected that the supply is also maintained, although, within the current circumstance, the housing sector is struggling to reach this new demand. Clements (2016) also indicates that Britain’s housing shortage has hit crisis point as the number of buyers ultimately outweighs the number of properties that are currently on sale.
Structure of the Dissertation
This dissertation consists of five chapters. The first one is an introduction, with the aim of exploring and analysing the background of the study, describing the research question and objectives of the study. Then it continues with the definitions of the main concepts, the significance of the study, as well as the delimitations.
The second chapter is the systematic literature review to understand the topic based on different point of views of the main contributors for Lean theories. It presents the background and the importance of Lean in the housing sector. It continues with understanding the challenges from the implementation of Lean.
The third chapter identified the relevant methodology concepts which were utitlised throughout the study. This chapter also demonstrated a comparison between certain concepts and approaches being chosen and why they were relevant for this type of study.
Furthmore, the fourth chapter analysed the data provided by the participants interviewed and establishing clear themes to support the overall research question.
The last and final chapter, concludes the research study, highlighting the proposed recommendations as well as taking each objective specifically and referring back to the data learned throughout the study. There is a summary of the research framework developed, that will help towards successful Lean implementation in the residential sector.
Figure 2 highlights the main chapters which were discussed and answered throughout the research study.
Figure 2: Structure of research study
2.0 Chapter Two – Literature Review
The research objectives guided the secondary research regarding exploring the implementation of the Lean construction approach to improve performance in the residential sector and the current housing crisis. The examination of existing literature about the objectives set were able to identify new lines of enquiry for further research.
Overall, this research investigated and compared Lean production to the traditional construction approach and how Lean could enhance the residential construction sector.
The housing crisis
Within the UK, there is a housing crisis impacting potential new buyers. Global Retail Estate Assets (2016) suggest that the gap between demand and supply in the UK property market specifically in London has widened dramatically and will grow steadily worse over time. At the current moment, it is evident that a residential building crisis is being faced by the country. Castella (2015) states that a decade ago, the Barker Review of Housing Supply found that approximately 250,000 homes needed to be built each year to prevent spiraling house prices and also a shortage of affordable homes. Likewise, Fraser (2016) suggests that building figures in London are currently stuttering.
Johnston (2015) also agrees with this and advised that just 125,110 homes were built in England in the year to March in 2015. This is roughly about half as many needed to keep up with demand, and the problem is therefore compounded every year. The National Housing Federation (2015) estimates that compared with the demand, there is now a shortfall of more than half a million dwellings which demonstrates a severe problem within the UK. This mainstream issue which is occurring indicates there needs to be an understanding of why the UK residential sector is struggling and a revaluation of the production tool and techniques which are presently being used. As seen in figure 3, it shows quarterly figures for house building starts and their completions are given on a seasonally adjusted basis.
Figure 3: Seasonally adjusted trends in quarterly housing starts and completions, England
Source: Department for Communities and Local Government (2015)
The figure highlights the trends experienced within the U.K and evidentially there was a sustained growth from 2001 until 2005. Moving forward from 2005 statistics were broadly steady in which on average there were around 44,000 units each quarter until late 2007. There was then a period which was strongly affected by the economic downturn. From the beginning of 2008, there was a rapid decline to a trough in the March quarter of 2009. Despite fluctuations and a clear indication of growth and decline throughout the period, it is clear that the housing situation is still not where it needs to be and matching the current demand (Office for National statistics, 2015).
Cost, immigration, and delivery of projects are not the only problems that the residential industry is facing as some designs may be too complex to build and may require significant time management. Some of the problems that are being faced have been resolved by taking a more traditional approach to solve them effectively. As stated by Masterman (2002) the concept of construction management has been identified as the planning of a particular project about the relevant resources being allocated to complete the project on time and budget.
Using relevant approaches and techniques can potentially enhance and improve the current housing crisis. Griffith (2013) suggests that to improve the current housing crisis, there needs to be the adoption of using different methodologies to build these houses and investing time and money into the approaches used. Likewise, NHBC Foundation (2016) indicates that traditional methods of construction have a long history in the UK and there needs to be changes to attitudes to think about more innovative methods being used amongst housing associations and house builders. Lean construction is a clear indication of a technique which can be used in contrast to the traditional constructional approach the UK has constantly been using.
Lean Production Background
Following World War II Japanese’s companies had been confronted with the actual problem associated with huge shortages associated with materials, monetary, as well as recruiting. Due to this, the Lean manufacturing concept was developed by Taiichi Ohno at Toyota Motor Company in the 1950’s. It was developed as “an innovative technique based on the mind and hand philosophy of the craftsmen era, merging it with the work standardisation and assembly line of the Fordism, and adding the glue of teamwork for good measure.” Krafcik (1988).
The concept behind Lean manufacturing is to minimise the amount of waste in a production line, reduction of operational costs and empowerment of employees (Womack and Jones, 2013). furthermore, Monden, (1998) further stated that the Japanese approach believes that customers are ultimately the generators of a selling price. This means that the more quality built within a product, the more service can be offered and ultimately the more the customer will be prepared to pay. The difference between the cost of the product and this price is what determines the profit (Monden, 1998).
Lean manufacturing principle is to work in every aspect of value stream by waste elimination for cost reduction, capital generation, boost sales, and global market growth. According to Hines and Taylor, (2000) value stream is defined as “the specific activities within a supply chain required to design, order and provide a specific product or value.”
The term “Lean” as defined by Womack and Jones (2013) as a system that utilises less, in term of all inputs, to create the same outputs as those created by a traditional mass production system. In addition, by utilising less it contributes increased varieties for the end customer stated by Panizzolo (1998). Therefore, the main principle of Lean is for organisations to reduce cost using continuous improvement, in the long run, costs of services and products can be reduced to generate profit for the organisation.
Persoon (2006) indicates that Lean manufacturing tool and techniques have been used widely in various industries such as the automotive industry such as the Toyota production line as seen in figure 4. However, the Lean concept is still not widely applied among the construction organisations and projects within the UK and therefore the purpose of understanding how Lean production can help is fundamental to enhance productivity and quality of future projects (Mossman, 2009).
Figure 4 shows the Lean system that was developed by Toyota; the pyramid consists of several levels that are required for the implementation of Lean (Liker, 2008). It is clear to see that it requires a number of different elements in order for Lean production to be implemented successfully.
Figure 4: Elements of Lean within the Toyota Lean production line
Source: Liker, 2008.
The Evolution of Lean Manufacturing to Construction
Lean was firstly adopted in a manufacturing sector which was in the Toyota construction plan. It is clear that lean manufacturing has evolved into lean construction, although it hasn’t been fully understood within the construction sector. The current construction sector processes are beginning to be more perplex and consequently such a comprehensible management method. Egan (1998) suggests that the application of Lean thinking to the design and construction process creates improved project delivery in order to meet client needs and improve efficiency. This indicates the involvement and added benefits that Lean consutrction can have on a number of other elements including the residential sector.
The main aim of the Lean concept is to minimise waste and maximise value by utilising the relevant Lean tools (Blakey 2008). Evidently, there are substantial variations in the manufacturing and construction sector but despite these differences, that they have they both share common targets and follow the same values such as work flow by removing difficulties, continuous improvement, system optimisation through collaboration and creating pull production.
Challenges arise when implementing a Lean methodology to construction because of the many significant differences which occur between manufacturing and construction. Further to this point, construction is site based and it accounts for a number of processes which need to be adhered to (Skitmore and Marson, 2004). Whereas, manufacturing requires machine power and the processes are the same and do not need to be changed. Although it is intended to be a resolution, it still highlights a lot of potential ways to ultimately advance the industry. (Hines et al, 2004)
Futhermore, Salem et al (2006) proposes that the contractor should always ensure that profound values for the established components when on site is mostly impacted by the site environments. Firstly, one-of-a-kind production presents the occurrence of customising elements in construction and that it tends to be much more advanced than in the manufacturing field where customers play a crucial character in customisation throughout a project (Koskela, 1992).
In contrast, manufacturing tends to be known for using specific and unique equipment to standardise the items that accept sufficient levels of customisations by the major retailers (Salem et al. 2006). On the other hand, complexity focuses on the construction process which is more complex, complicated and dynamic. Therefore, each project is viewed as a new duty which is accompanied by the different designs and resources with adjustable and flexible specifications.
This is contrary to manufacturing where the production method is maximised by using focused facilities with relevant technology and resources to assure the reliability and smooth running of the product (Aziz, 2013). Some of these features cause a lot of reservations in the whole of the production process. Therefore, causing significant impacts on the overall cost and time of the project and the process that it goes through (Salem et al. 2006).
Regardless of the variations in the manufacturing and construction sectors, they tend to both focus on producing competitive products which require the shortest manufacturing time with low cost, quality and the maximum value (Zimmer, 2005). Ultimately, each of the different industries has their approaches to achieve the success of Lean and how it is implemented into their projects to be most effective (Staats and Upton, 2011).
Lean Construction Principles
According to Howell and Lichting (2008), the aim of approaching projects as production systems is to change the structure of work in both design and construction to maximise project performance. Lean principles present whole process optimisation through collaboration, continuous improvement, elimination of waste and customer satisfaction by delivering the value desired by the end-user (Enache-Pommer, et al. 2010). Lean construction thinking applied to production systems on site has increased awareness of the benefits of stable work, of pull flow of teams and materials to reduce inventories of work in progress (WIP), and of process transparency to all involved (Sacks, Treckmann and Rozenfeld 2009). Lean construction concentrates efforts on defect prevention (Salem et al, 2006).
Seven Types of Waste in Construction
Lean focuses on the abolishment or reduction of waste. In addition to the abolishment or reduction as well as the capitalisation or utilisation of activities that add value to customers. From a customer’s point of view, the value of a product or service is correspondent to anything that they are willing to pay for it. Therefore, waste elimination is the basic principle of Lean construction. Russell and Taylor (1999) define waste as anything other than the minimum amount of equipment materials, parts, space, and time that are essential to add value to the product. This was furthered by Nicholas (1998) in which waste can take in any form and can be of complexity, labour, overproduction, space, energy, defects, material, time and transport. The different types of waste are identified in tables below:
Table 1: Types of Waste
Table 1 Comparison of Over processing
Table 2 Comparison of Transportation
Table 3 Comparison of Waiting
Table 4 Comparison of Inventory
Table 5 Comparison of Overproduction
Table 6 Comparison of Motion
Table 7 Comparison of Defects
Lean Tools and Techniques
There is a range of Lean tools and techniques that have been developed for the manufacturing sector. These can vary dependent on the industry and the organisation executing them. Recently, these techniques have tools have been applicable in the automative industry. The main objective of Lean is to reduce waste and increase productivity. Lean concepts and techniques are explained below:
The 5S concept is an organised aproach which was presented in the early 1980s by Takashi Osada. According to Jimenez et al. (2014), 5S is a workspace management method which emerged in Japan as a consequence of the application of the Kaizen culture and is a vital tool for organisations to date. In this context, Sui-Peng and Khoo (2001) stated that the 5S is the acronym of five Japanese words which are:
• ‘seiri’ which means tidiness or simply known as sort,
• ‘seiton’ which translate to orderliness (straighten)
• ‘seiso’ meaning cleanliness (shine)
• ‘seiketsu’ which means standardization
• ‘shitsuke’ which means discipline (sustain).
(Bronski and Iannello, 2016)
The 5S concept is illustrated in figure 5. This gives a clear understanding of the concept and how they interlink together.
Figure 5: The 5S Concept
Source: The Lean Accountants (2011)
Ikuma and Nahmens (2014) view the 5S concept as a way to yield efficiency and allowing more organisation in the work environment. In this regard, the 5S will create a more pleasant work atmosphere which will boost the employees’ morale thereby leading to improved attitudes. Furthermore, Neuwirth, (2017) pointed out that the 5S concept contributes to the management practice which also leads to the creation of a better workplace in so doing plummeting the employees’ workload as well as mistakes. This in turn leads to neatness and a healthier atmosphere as well as providing training and education to employees to enhance their quality and productivity (Forbes and Ahmed, 2010).
Rexhepi and Shrestha (2011)stated that “In the beginning, 5S methodology was used to develop an integrated management system which developed in the total production maintenance (TPM) highlighting the importance of the tool.” Khamis et al. (2009) furthered this by indicating that the 5S tool is a technique used to maintain and establish a quality environment in an organisation.
Morrow and Main (2008) and Bicheno (2004, p. 52) agree that 5S is a simple and helpful tool to create a Lean culture within an organisation. Sort emphasizes on putting the material that is part of final product or service in the right order (Morrow & Main, 2008). Bicheno (2004, p. 52) suggest that organisations should try to analyse different items, and throw those that are not used. As stated by Wastradowski (2015) the tool 5S hopes to create efficiently and keep workplaces organized and equipped to carry out daily tasks in a safe manner. However, it does require resources to become an effective tool for companies.
Futhermore, Vaidya (2015) reported that the implentation of Lean 5S approach and the initial use of applying the concepts cou;d be reduced by 70% during certain surgical procedures. Although, not necessarily applicable to the construction industry, this highlights that if the tool is used appropriately, it can have effective and positive implications.
Oakland and Marosszeky (2017) suggest that Collaborative planning is one Lean construction tool that is highly recommended. It is known to improve collaboration and communication between the project participants. Skanska, (2012) evokes that the key words for the collaborative planning reliability, predictability and lastly programme compression. The collaborative planning concept aims to continuously produce a plan that defines the intended work subjected so that the resolution of issues can ensure the reliability of assumptions (Alarcon, 1997). A factor that might be important in the planning is ensuring that the right people are constantly available. This way they can make the crucial decisions which are needed so it eliminates delays and increases productivity. The collaborative planning technique is interlinked to teamwork concepts and ultimate production control.
Ballard and Howell, (2003) state that all members of the project such as designers, contractors, sub-contractors and clients need to be involved in the planning. Management and leadership are important when it comes to the implementation of Lean (Koskela, 1992). It is essential that the management must create an environment that is suitable for the adoption of Lean and for them to understand the Lean philosophy. For the implementation to be a success the management will need to ensure that they are the ones who facilitate it, rather than having external experts and specialists. This type of implementation needs to be made directly by the management, not by external specialists or experts.
According to Womack et al. (2007), the design stage of a Lean system consists of four core factors. These factors are teamwork, simultaneous development, communication and leadership. Compared to large production, Lean production emphasise on putting effort at the first stages of the design process to mitigate the risk of having problems down the production line as it would require more effort to sort it out (Kotter, 2012). The utilisation of simultaneous development ensures that the production can be carried out before the final design is finalised, in a Lean production system. This is made possible because of the strong communication link between the production and design teams. Comparing with mass production, the final design of a product is required before production can commence. Lean has to be implemented among all employees, e.g. managers, leaders and front-workers, or as stated by Gao and Low (2013). They suggested that without good leadership, commitment, long term relationships with stakeholder and partners, the implementation of Lean will not be effective and remain incomplete.
Skanska (2012) suggest that the collaborative planning can be split into four different components. These are:
• Look ahead planning
• Master planning session
• Daily/weekly coordination meetings
• Lean daily briefings
The collaborative planning is not exactly something new, it is just a more efficient way of working and collaborating to ensure the best results for projects. One of the concepts which will be further discussed is look ahead planning. This was identified by Hamzeh et al (2012) as the key focus when understanding collaborative planning within the lean implantation.
Look ahead planning
There is also the look ahead planning schedule which focuses on the form of the work flow and matching it with the available resources as well as developing details about the operation of the assignments (Ballard and Howell, 2003). The look ahead plan also consists of maintaining the backlog of ready work and eliminating delays (Hamzeh et al, 2012).
This technique is used to take control over the production (Ballard, 1997). The construction foreman or front line supervisor commits to a weekly plan of tasks. The tasks or activities are from a typically 6-week look ahead plan where constrains and problems are shown. Cohn (2006) evoke that as part of this technique it allows for greater detailed planning which allows for the closeness to work performance. Within the look ahead planning tool, the individual tasks need to be based on quality requirements to increase the feasibility of the actual task. The tasks are monitored and the percentage of the planned tasks completed are determined at the end of the week. This is to track and measure the completeness (Forbes and Ahmed, 2012). Once tasks are completed, the reasons for any failures are evaluated for continuous improvement moving forward. Hamzeh et al, (2012) suggest that there needs to be the rethinking of the lookahead planning tool in order to optimise construction workflow.
Despite the advantages of this system (Alarcón and Cruz 1997, Gonzalez et al. 2008), the current practice on many construction projects shows a poor implementation of lookahead planning resulting in a wide gap between long-term planning (master and phase schedules). Furthermore, short-term planning (commitment/weekly work plans) reduces the reliability of the planning system and the ability to establish foresight.
Last Planner System
Another concept within lean implementation is the last planner system. This technique focuses on the work made on request not command (Ballard and Tommelein, 2012). Further to this, Munje and Patil (2014) indicates that Last Planner System (LPS) is an important technique of lean construction, which allows for a sequence of work and project variability in construction. Given the industry is constantly changing, this tool allows for adjusting and adaptation.
The Last Planner is the team or person which is assigned for operational planning, this facilitates and allows for the improvement of sequence work aswell as the achievement of individually assigned task at the operational level (Muje and Patil, 2014). Ballard and Howell (2003) discussed the last planner system as a tool which improved the reliability and had the ability to predict the construction production process. Further to this, Mossman (2013) indicates the last planner tool increases safety and reduces waiting time, in addition to reducing costs and decentralising decision making.
Moreover, the last planner tool can manage relations and allows collaboration to ensuring that the right production decisions are made. It allows for the involvement of all stakeholders including the lower level of employees that are involved within the project (Mossman, 2013). The tool has great successes as stated by Chick (2003) where it has been identified that through utilising the last planner tool, there was a 30% improvement in the rebuilding time for runways. Ballard (2000) indicated the last planner system has been successfully applied by companies which have direct responsibility for production management such as speciality or bespoke contractors.
However, Mossman (2013) mentioned that last planner in a systematic matter then the likelihood is that it will fail. Further to this, there is high risks of costs, time and quality blowouts when last planner tool is not implemented and utilised properly as suggested by Davies et al, 2011. To add to this, a concern regarding the use of the last planner system, it is difficult to implement if the system is known by a minimum work force beforehand (Simonsen and Lemming, 2015).
Just in Time
Just in time is another main principle that is closely related to Lean production, it is a management idea that attempts to eliminate sources of manufacturing waste by producing the right part in the right place at the right time. According to Nahmias (1997), this system addresses waste such as work-in-process material, defects, and poor scheduling of parts delivered. As suggested by Preston (2014) Just-in-Time is just one method which has its set of principles and practices. It often applies only to the production aspect of a particular business. Whereas, Lean encompasses all areas of the business, by having different methods for the numerous departments in the organisation.
In addition, the Just-in-time concept enables the internal process of a company to adjust and react to sudden changes in the demand pattern by producing the right product at the right time, and in the right quantities according to Monden (1998). However, just in time is a fundamental tool for management of an organisation’s external activities such as distribution and purchasing. Karmarker (1989) states there is increasing importance situated on relatively stable demand, which allows for efficient capital utilisation rates. Alarcón (1997) argues that without stable demand, just in time becomes untenable in high capital cost production. This evokes the importance of using such method and the types of organisations that can optimise from this tool.
Continuous Improvement, Learning and Quality
Continuous improvement is an important element of Lean as it improves productivity on construction projects. Gao and Low (2013) state that construction projects should expose problems easily to facilitate with continuous improvement on a project. As current, the construction industry has a blaming attitude, this needs to change in order to motivate employees so they are willing to identify solutions to problems. For problems to become opportunities for continuous improvement, it needs involvement from all employees. When the problem has been identified there needs to be a period of reflection where solutions can be created to mitigate the same problem from coming up in other projects.
Implementation and Compatibility of Lean in Construction
Implementation of Lean
According to Emilian (2013) to help an organisation survive specifically for the long term, as there are changing conditions and new competition, if lean is done successfully, it can make an organisation more flexible adaptable to change. With the construction industry, applying the lean concept enables adjustments to be made and allows for organisations to better serve their customers over time (Pink et al, 2013).
The trend in businesses implementing Lean is increasing as this removes waste from the construction project, team commitment is built, processes are streamlined and there is continuous improvement of the project. However, this contrasts with theory from Netland (2015) whereby two out of three Lean programs fail to achieve their initial objectives. This is on the basis that they are not fully implemented correctly. Mossman (2013) suggests that Lean needs to be implemented properly with the relevant tools and techniques for the benefits to be seen.
For Lean to be successful in an organisation, the management has to be committed as this is necessary for them to lead and give support to the organisation (Castella, 2015). The workforce of the organisation will also need to be trained and educated in Lean, as if they are not provided with the knowledge the implementation of the Lean will not be successful (Womack, 1990). It is important for organisations to understand that when implementing Lean, the results will not be seen overnight, it takes evolving and reviewing each technique and tool.
Compatibility of lean when compared to traditional construction
In order for Lean to be compatible for the construction industry, there needs to be the understanding of how it differs from current traditional processes. To be fully effective, the problems within traditional construction management are discussed to allow Lean to be a solution. Koskela (year) states that the conceptual approach to traditional construction processes is that it neglects non value-added activities which therefore leads to an uncontrolled and unpredictable variability of production. Munje and Patil (2014) furthers this by stating that the traditional construction approach focuses unsynchronised processes and creates a major gap between planned work and the actual amount of work achieved. Whereas, Forbes and Ahmed (2010) suggest that lean construction differs significantly from the traditional approach as processes within Lean construction are actively controlled and metrics are utilised in the planning system to allow for reliable workflow and the ability to predict outcomes for a project.
In addition, traditional production management is based on ‘pushing’ work to the companies and their subcontractors in objective to perform the tasks planned whether or not these stakeholders have all the necessarily resources needed (Bajjou, 2017). When compared to Lean construction, the concepts within Lean adopt a pull strategy specifically within the tool just in time whereby Kanban cards are used to reduce the amount of inventory and ensure resources are in the right place at the right time (Enhassi and Zaiter, 2014).
Furthermore, Forbes and Ahmed (2010) states that lean construction involves more short-term planning and control that ultimately improves the time taken to complete job tasks ensuring that projects are completed on time. Whereas with the traditional construction approach, there is not necessarily enough focus on planning and therefore causes disruption to the completion of tasks. In addition to this, the traditional construction approach does not focus on decreasing the production of waste, contrary to lean construction which the core principle is to reduce waste and non-value adding activities (Tessari, 2015).
Norris (2017) from Lean Consulting Works suggests that lean construction is always looking for ways to improve processes. Whereas, in contrast the traditional construction approach states that if a process is currently working then there is no need to fix it. Within the construction industry, there are lots of factors which are evolving and as technology improves, there needs to be more emphasis on looking towards new processes and ways to adapt (Gallagher, 2017).
Likewise, it has been suggested by Norris (2017) that lean construction view problems as opportunities for improvement often through using the root cause analysis. Comparing this to the traditional construction approach, problems are viewed as just problems. Proverbs et al (2000) stated that within the UK construction industry, the focus on a blame culture is one of the major problems being faced. As seen in table 8, it highlights the differences between the two different construction approaches.
Table 8 Comparison of Lean construction to Traditional Construction
Source: Bajjou (2017)
Critical Success Factors of Lean Implementation
For Lean construction implementation to be deemed successful there are critical success factors (CSF) that need to be followed. These factors include the use of Lean techniques and tools, having a plan or vision, resource allocation and training.
Training of employees is a key CSF for lean implementation. If employees are not educated or aware of the fundamentals of Lean, the implementation will not be successful. Netland and Fredows (2016) propose that within the early stages of Lean implementation, internal corporate resources or eternal consultancy firms can help ensure and build the required knowledge needed. A good start for success is to benchmark organisations which have successfully implemented Lean (Chan, 2004). Further to this, Alarcon (1997) state without the training, employees will not feel involved and therefore this can jeopardise the completion of tasks.
Having a vision of where an organisation wants to be or position itself is meaningless if there is no detailed plan for how this vision will be accomplished. Cain (2008) suggests that having a plan is an important CSF for Lean to be implemented successfully. Steps of how the plan will be delivered will need to be clearly defined. These steps will need to be monitored in the form of performance targets and monitored regularly with involvement from all stakeholders.
According to Netland and Fredows (2015) allocating the necessary resources to assist implementation and then sharing these gains amongst all employees is definitely crtiical for success. A budget for the implementation of Lean will have to be allocated for the transformation as this is very important. The improvements gained in the transformation process will need to be shared amongst the team. Chiang et al (2015) propose that during the early stages there needs to be the introduction of reward schemes. This ensures employees feel appreciated and recognised by the management team for the effort put in. without this critical success factor, lean implementation is not at it’s full effect.
Use of tools and techniques
Utilising Lean tools and techniques is the last main CSF, as is crucial for any successful lean implementation. The Lean tools and techniques that are commonly used according to Netland (2015) are “waste reduction, visualisation, problem-solving, team concept, continuous improvement, daily management, value stream mapping, and 5S.” Achanga et al (2006) furthers this by stating these techniques are well known for the Lean methodology. Lean tools and techniques are necessary and effective for the implementation of Lean; they are not efficient if they are to be implemented on their own the other critical success factor will need to complement them (Forbes and Ahmed, 2010).
Challenges of Implementing Lean
Despite the apparent benefits from Lean construction practice over the past two decades, the uptake of the Lean concept in the UK seems to be sparse (Bashir, 2015). When it comes to constrction projects the implemeantation of Lean can be challenging. The learnings and principles of Lean manufacturing are compatible to the construction sector, however the need to be fully adapted in order to reach maximum benefits. The implementation of Lean in the construction sector is different due to the diffrence in nature of construction processes as opposed to maufacturing proccesses as stated by Sarkar (2009).
The identification of Lean challenges can be carried out in various ways. Ingram (2016) suggests that Lean manufacturing relies on smaller workforces where employees are highly trained, change in company culture and integrated technological systems. Each of these elements can present distinct challenges that must be overcome to achieve a truly efficient lean manufacturing system. Pearce (2013) adds to this by stating that lean can be difficult to implement and apply in specific organisations. One of the main reasons for this is the complicated factor of change management. Lean implementation is a transformational process and needs to support the overall organisation development aswell as improving processes, further agreed by Mossman (2013). Miina (2012) adds to this that success or failure of lean initiatives strongly depends on companies approach to it and on whether company has created they own philosophy towards lean – lean house. Therefore, it is clear that each individual company needs to fully understand and value the lean concept in order for the benefits to show.
Some of the factors that contribute to the challenges that Lean implementation are faced with are mentioned in Table 9.
Table 9Challenges of Lean Manufacturing Implementation.
CODE CHALLENGE OF LEAN IMPLEMENTATION
1 Uncertainties in demand
2 Pressure from customer
3 Pressure from top management
4 Noneffective method (e.g., inventory management)
5 Knowledge and information transfer (effective communication)
7 Lack of common vision
8 Non-Lean behavior (increase flow time, increase waste)
9 Projects implementation
Source: Cheah, Peng & Deng (2012)
Throughout this chapter it has been identified that the UK is facing a housing shortage and at the current rate at which new builds are being built, the annual target will not be met. The benefits of Lean being implemented in the Toyota production line have given a new perspective on how these principles and tools could be implemented in the residential sector. As Toyota was able to cut down it’s lead times, the same can happen for residential projects if Lean is implemented correctly. It has been seen that Lean has evolved over the years and needs to be considered more for the construction industry specifically residential projects to help tackle the current housing crisis.
From the research in this chapter, it is clear there are a variety of different Lean concepts and tools which need to be adhered to or considered to ensure success on projects. As there are several techniques, it is crucial that organisations adapt the relevant techniques which can create value to their specific projects. There is no blue print that shows how to implement Lean construction and achieve the various benefits associated with it, as it is widely dependent on how the company implements Lean.
Lastly, concluding this chapter, it is evident that the primary objective of Lean is to reduce non value added activities, continous improvement and inccreasing value for the customer. When compared against the traditional construction approach, Lean construction has some added benefits and views concepts in a new way which can help aid the current housing crisis. However, it is apparent that there are some challenges faced when implementing Lean such as resistance to change and non-Lean behavior. Although by using critical success factors such as training and having a vision it can potentially overcome these challenges.