Tese de mestrado integrado. Mestrado Integrado em Engenharia Civil - Especialização em Construções Civis. Faculdade de Engenharia. Universidade do Porto. 2012

Purpose: As of today, the knowledge of lean production, and its development into the construction industry, lean construction, has been well described in most of the necessary aspects. In what way lean could affect the work environment in a construction project, be it good or bad, has to date not been thoroughly documented. In Sweden, lean has been mildly tested in the construction industry but the results concerning the effect it has on the work environment is yet to be found in the literature. Lean itself is a strategy for manufacturing processes. The purpose of this study is to contribute to the knowledge of lean itself and how it, theoretically, could affect the work environment at construction site. Method: To achieve the purpose, documents from the participating company concerning work environment has been analysed in order to visualize what routines the company currently follows. In addition to this, seven interviews were conducted with employees of the company. The persons participating in the interviews were asked about how well they think the work is organized on the construction site right now and furthermore about their thoughts of lean-concept that had been produced, based on the theoretical framework. Findings: Based on the theoretical framework and findings in the empirical data that has been collected, a lean-concept was developed and refined. The concept includes what routines and what documents that are vital when implicating lean in an effective way, and also what needs to be considered in order not to impede the work environment at the construction site. Implications: Implicating a well-structured lean-concept in the construction process of a project would, theoretically, most definitely improve effectiveness within the project. It could also improve the work environment of the project, considering the risk awareness and the easier waste-control that the concept could provide. However, it could also make it worse through the elimination of variance and monotonous work tasks that are needed to improve the effectiveness. Limitations: The most important limitations that the study has had is the fact of it only being a theoretical implication of a lean concept, not a practical case study of the sort. This is due to the defined and limited time that project has had. In addition, the study has also had to limit its’ research to the frame supplement phase of the construction project. This is because of the fact that the work with the theoretical framework and the empirical study would have been too overwhelming, had the study considered the entire production phase of a construction project.

<p>Byggbranschen brottas idag med en hel del fel och brister i byggprocessen. Exempel på problem är bl.a. höga byggkostnader, kvalitetsbrister samt att det förekommer slarv och okunskap. Produktiviteten i byggbranschen har inte utvecklats lika mycket som i tillverkningsindustrin som använder sin ledningsfilosofi Lean Production.</p><p>Syftet med detta examensarbete är att få insikt i vilka vanliga fel och brister som förekommer i byggbranschen, samt att kunna ge förslag till förbättringar i enlighet med lean-tänkande. När man talar om Lean i byggsammanhang benämns det Lean Construction. Lean Construction har sin teoretiska bakgrund i verkstadsindustrins Lean Production och Lean Thinking.</p><p>Lean Production är en industriell produktionsmetod vars syfte är att öka produktionseffektiviteten och har sin bakgrund i japanska bilindustrin. Lean Thinking är en vidareutveckling av Lean Production och är ett begrepp som används för att omfatta fler branscher utöver tillverkningsindustrin. Att arbeta enligt Lean innebär att hela tiden arbeta med ständiga förbättringar samt att identifiera och eliminera allt slöseri. Slöseri kan ses som en aktivitet som inte skapar något värde för kunden men som ändå förbrukar resurser.</p><p>När man tillämpar Lean i sin organisation så analyserar man hur en effektivisering kan ske utifrån sin egen produktionsprocess. Några av grundelementen inom Lean är Kaizen som betyder ständiga förbättringar samt Just In Time.</p><p>Det har utförts vissa studier kring slöseri i byggbranschen, delar av dessa presenteras i denna rapport. Det som kartlagts som slöseri är bl.a. omarbete, materialspill, överproduktion och väntan hos personal. Det är utifrån dessa kartlagda slöserier som vi har utformat enkäterna i vår undersökningsstudie.</p><p>Studien visar inte på några större skillnader mellan platschefer/arbetsledare och yrkesarbetare vad det gäller deras uppfattning om vilka fel och brister som är vanligt förekommande. Båda yrkeskategorierna är överens om att slöseri kan minskas, t ex genom effektivare materialhantering på byggarbetsplatserna och bättre kommunikation och planering på alla plan.</p> / <p>The Construction industry struggles with quality deviances and defects in the building process. Various kinds of problem are for example expensive costs for production, defects in quality and negligence and ignorance in the industry in general. The development of productivity in building process has not progressed at the same rate as companies within manufacturing industry who are using the Lean Production philosophy.</p><p>The purpose whit this degree project is to bring knowledge about what kind of deviances and defects that exist in the industry, and to recommend suggestions for improvements in accordance with Lean Thinking. When you speak about Lean in the construction business it is called Lean Construction. Lean Construction has its theoretical background in the engineering industries Lean Production and Lean Thinking.</p><p>Lean Production is an industrial production method which purpose is to increase the effectiveness of production. It originates from the car-industry in Japan. The concept of Lean Thinking is a further development of Lean Production and it includes all industries, not just the manufacturing industry. To work according to Lean means that you all the time tries to achieve constant improvements and to identify and eliminate all kinds of waste in time and materials. Waste can be seen as an activity that do not create any added value for the customer but still however consume resources.</p><p>While implementing and using Lean in your business corporation you have to analyze how a potentiate can be achieved outgoing from the existing production process. Some main elements within Lean are Kaizen, which means constant improvements, and Just In Time.</p><p>There have been many studies about waste in production in the construction industry. Some are introduced in this report. Activities that have been identified as waste are among others reworking, waste of material, overproduction and misplanning causing waiting times among employees. Based on these ascertained wastages we have formulated the questionnaire study.</p><p>The study does not show large differences between local managers/team leaders and construction workers when it comes to their opinion about what kinds of deviances and defects they find as frequent. The both professions agree that waste can be reduced, by the way of for example efficacious material handling on the building sites and better communication and planning on several levels.</p><p>Keywords: Building process, Lean Construction, Wasting, Kaizen and Just In Time</p>

Byggbranschen brottas idag med en hel del fel och brister i byggprocessen. Exempel på problem är bl.a. höga byggkostnader, kvalitetsbrister samt att det förekommer slarv och okunskap. Produktiviteten i byggbranschen har inte utvecklats lika mycket som i tillverkningsindustrin som använder sin ledningsfilosofi Lean Production. Syftet med detta examensarbete är att få insikt i vilka vanliga fel och brister som förekommer i byggbranschen, samt att kunna ge förslag till förbättringar i enlighet med lean-tänkande. När man talar om Lean i byggsammanhang benämns det Lean Construction. Lean Construction har sin teoretiska bakgrund i verkstadsindustrins Lean Production och Lean Thinking. Lean Production är en industriell produktionsmetod vars syfte är att öka produktionseffektiviteten och har sin bakgrund i japanska bilindustrin. Lean Thinking är en vidareutveckling av Lean Production och är ett begrepp som används för att omfatta fler branscher utöver tillverkningsindustrin. Att arbeta enligt Lean innebär att hela tiden arbeta med ständiga förbättringar samt att identifiera och eliminera allt slöseri. Slöseri kan ses som en aktivitet som inte skapar något värde för kunden men som ändå förbrukar resurser. När man tillämpar Lean i sin organisation så analyserar man hur en effektivisering kan ske utifrån sin egen produktionsprocess. Några av grundelementen inom Lean är Kaizen som betyder ständiga förbättringar samt Just In Time. Det har utförts vissa studier kring slöseri i byggbranschen, delar av dessa presenteras i denna rapport. Det som kartlagts som slöseri är bl.a. omarbete, materialspill, överproduktion och väntan hos personal. Det är utifrån dessa kartlagda slöserier som vi har utformat enkäterna i vår undersökningsstudie. Studien visar inte på några större skillnader mellan platschefer/arbetsledare och yrkesarbetare vad det gäller deras uppfattning om vilka fel och brister som är vanligt förekommande. Båda yrkeskategorierna är överens om att slöseri kan minskas, t ex genom effektivare materialhantering på byggarbetsplatserna och bättre kommunikation och planering på alla plan. / The Construction industry struggles with quality deviances and defects in the building process. Various kinds of problem are for example expensive costs for production, defects in quality and negligence and ignorance in the industry in general. The development of productivity in building process has not progressed at the same rate as companies within manufacturing industry who are using the Lean Production philosophy. The purpose whit this degree project is to bring knowledge about what kind of deviances and defects that exist in the industry, and to recommend suggestions for improvements in accordance with Lean Thinking. When you speak about Lean in the construction business it is called Lean Construction. Lean Construction has its theoretical background in the engineering industries Lean Production and Lean Thinking. Lean Production is an industrial production method which purpose is to increase the effectiveness of production. It originates from the car-industry in Japan. The concept of Lean Thinking is a further development of Lean Production and it includes all industries, not just the manufacturing industry. To work according to Lean means that you all the time tries to achieve constant improvements and to identify and eliminate all kinds of waste in time and materials. Waste can be seen as an activity that do not create any added value for the customer but still however consume resources. While implementing and using Lean in your business corporation you have to analyze how a potentiate can be achieved outgoing from the existing production process. Some main elements within Lean are Kaizen, which means constant improvements, and Just In Time. There have been many studies about waste in production in the construction industry. Some are introduced in this report. Activities that have been identified as waste are among others reworking, waste of material, overproduction and misplanning causing waiting times among employees. Based on these ascertained wastages we have formulated the questionnaire study. The study does not show large differences between local managers/team leaders and construction workers when it comes to their opinion about what kinds of deviances and defects they find as frequent. The both professions agree that waste can be reduced, by the way of for example efficacious material handling on the building sites and better communication and planning on several levels. Keywords: Building process, Lean Construction, Wasting, Kaizen and Just In Time

This report, written by Måns Ridzén and Jonas Stenberg, presents the thesis carried out the spring of 2012. The authors met the first time in 2008, when they started their studies at Uppsala University. Since then they have completed various projects, both within and without the university. This study is based on a theory that was first conceived when Jonas Stenberg did his internship in the summer of 2010. The theory states that blueprint management is carried out wrong. This statement does not only concern specific companies, but the entire Swedish construction industry. Sustenance for this thesis can be found in earlier research done about waste and communication in the construction industry. The expenditures behind the waste and the communication can be connected to incorrect blueprint management. The thesis is divided into three main groups to make it more clearly for both the authors and the participants of the study. Based on these main groups, four questions are asked; who, what, why and cost? To gather information to answer these questions people with different expertise is asked. The result gathered is then analyzed and the four questions are answered. The goal to find an example that contributes to waste is succeeded and examples are brought up in the report. The conclusion is that there is a big waste in the construction industry and that this waste. / I denna rapport, skriven av Måns Ridzén och Jonas Stenberg, presenteras exa- mensarbetet som genomfördes våren 2012. Författarna träffades redan 2008 då de började sina studier vid Uppsala Universitet. Sedan dess har de genomfört flera projekt, både inom och utanför universitetet. Studien bygger på tesen ”fel ritningshantering”. Problemet är något som berör hela branschen och som kos- tar det svenska samhället många miljoner varje år. Stöd för denna tes finns i ti- digare genomförd forskning som berör slöseri och kommunikation inom byg- gindustrin. Både kostnaderna bakom slöseriet och onödig kommunikationen kan kopplas till felaktig ritningshantering. Tesen delas in i tre huvudgrupper för att göra det tydligare för både författare och deltagare i studien, dessa huvudgrupper är: fel version, felavläst och felri- tat. Med dessa tre huvudgrupper som utgångspunkt ställs fyra frågor; vem, vad, varför och kostnad? För att besvara dessa frågor söks information genom tre kanaler; projektörer, tjänstemän inom produktion och hantverkare. Resulta- tet skiljer sig mellan de olika kanalerna, d.v.s. att de olika aktörerna i byggpro- cessen har olika bilder över hur verkligheten ser ut. Dock så är det vissa punk- ter där alla aktörer är överens. Efter att resultatet samlats in så analyserades det. Analysprocessen har som mål att besvara de fyra frågor som ställdes i början av studien. Flera exempel på fel observeras i studien. Ett exempel berör pålning, där fel ritning användes och resulterade i en omkostnad på över 188 000kr. Slutsatsen är att fel ritningshan- tering kostar branschen miljoner, om inte miljarder, årligen. Dessa kostnader döljs ofta inom budgeten för produktion, även om de uppkommit redan under projekteringsstadiet. Författarna ger flera rekommendationer till åtgärder för att begränsa dess kostnader. Rekommendationerna berör b.l.a. vikten av att lyfta fram dolda kostnader i ljuset, samt att anpassa ritningen efter rätt ändamål. Rapporten gräver djupt ner i ett känsligt ämne och lyckas på ett lättsamt sätt presentera hur verkligheten ser ut idag. Fortsatta studier inom ämnet är en nödvändighet om Sveriges byggindustri ska behålla kontroll över den svenska marknaden i en allt mer globaliserad värld.

The purpose of this Master Thesis is to study how the value stream mapping concept can be applied along the construction supply chain for prefabricated massive timber floor elements. Identification and qualification of waste are starting points to propose suggestions on how to reduce and/or eliminate them. In order to use the value stream mapping along the construction supply chain, pertinent data has been collected and analyzed. To conduct the value stream mapping, the first three steps of the lean thinking principles in construction have been followed. The first step aims at defining the customer and his value as well as the value for the delivery team and how it is specified in the product. The second step is based on identifying the value stream and this is done through defining the resources and activities needed to manufacture, deliver and install the floor elements. This is conducted by using the VSMM methodology. In addition the current practice should be standardized and key component suppliers should be defined and located. The third and last step identifies non-value adding activities, in other words waste and suggestions on how to remove and/or reduce waste have been reached. Wastes from product defects, transportation waste and waste of waiting were to be found in the construction supply chain. Propositions to reduce and/or eliminate wastes were to implement a more careful planning of the manufacturing process and production schedule, to apply lean production principles in the manufacturing facility and decrease and or eliminate storage time. The study made has shown that in the supply chain of massive timber floor elements at Limnologen there is a big potential to lower costs and increase customer value as value added-time accounted for only 2% of the total time.

One of the major change efforts for the construction industry is lean construction. This thesis analyzes the practices of the construction companies in Turkey from the lean construction perspective. Prior to the analysis in question, requisite information about change in the construction industry, lean thinking and lean construction will be presented. A questionnaire, based on a lean construction model, is used to survey the practices and gather the data for the analysis. Various statistical analysis methods are performed on the gathered data to make inferences. According to these analyses, the lean construction characteristics of the construction companies will be discussed and the recommendations for improving the lean conformance of the construction companies will be presented.

ABSTRACT A GUIDE FOR CONSTRUCTION COMPANIES TO APPLY LEAN SIX SIGMA METHODOLOGY D&Uuml / gME, Fatma Zehra M.S., Department of Civil Engineering Supervisor: Asst. Prof. Dr. Yasemin NIELSEN April 2008, 245 pages The construction sector is an immensely important industrial sector in terms of economic and social impact and also employment facilities. Nonetheless, much research has pointed out a gap in terms of labor productivity, quality, performance and responsiveness to customer needs when compared with other large industrial sectors / sectors that have recently experienced huge gains and cost reductions via methods like Lean Six Sigma. In this study, the construction industry will be examined for determination of the potential Lean Six Sigma implementation level and expected benefits from its use. The author conducted interviews with three companies in order to find out their readiness for such a management by innovation. One of the companies was selected for further study due to suitability of their organizational structure, innovative strategy and interest in this study. By taking up this pilot study and Lean Six Sigma principles as references, five roadmaps are generated as a guidance to implement Lean Six Sigma methodology for companies indicating the general steps before and during the implementation. The proposed roadmaps and applied questionnaire/interview questions developed in this thesis will also be helpful to construction companies to scrutinize their own structure and performance levels and as a guide on how to pursuit improvements through the proposed implementation of the Lean Six Sigma methodology.

<p>The purpose of this Master Thesis is to study how the value stream mapping concept can be applied along the construction supply chain for prefabricated massive timber floor elements. Identification and qualification of waste are starting points to propose suggestions on how to reduce and/or eliminate them. In order to use the value stream mapping along the construction supply chain, pertinent data has been collected and analyzed. To conduct the value stream mapping, the first three steps of the lean thinking principles in construction have been followed. The first step aims at defining the customer and his value as well as the value for the delivery team and how it is specified in the product. The second step is based on identifying the value stream and this is done through defining the resources and activities needed to manufacture, deliver and install the floor elements. This is conducted by using the VSMM methodology. In addition the current practice should be standardized and key component suppliers should be defined and located. The third and last step identifies non-value adding activities, in other words waste and suggestions on how to remove and/or reduce waste have been reached. Wastes from product defects, transportation waste and waste of waiting were to be found in the construction supply chain. Propositions to reduce and/or eliminate wastes were to implement a more careful planning of the manufacturing process and production schedule, to apply lean production principles in the manufacturing facility and decrease and or eliminate storage time. The study made has shown that in the supply chain of massive timber floor elements at Limnologen there is a big potential to lower costs and increase customer value as value added-time accounted for only 2% of the total time.</p>

A Construção Enxuta (CE) tem sido introduzida, gradativamente, na construção civil através de práticas como controle de perdas, gestão da qualidade e planejamento e controle da produção. Tendo em vista a disseminação da CE na indústria da construção, há a necessidade de medir o nível do seu uso nas empresas, o que permite identificar melhores práticas e oportunidades de melhoria. Desta forma, o presente trabalho tem por objetivo desenvolver um protocolo de auditoria do uso de práticas da CE. Esse método foi desenvolvido ao longo de quatro etapas: (a) uma revisão da literatura para identificar categorias de práticas da CE, tendo como base o material publicado nos anais dos eventos do International Group for Lean Construction (IGLC) entre 1993 e 2010; (b) definição de fontes de evidência para avaliar o uso de cada categoria de prática; (c) definição de pesos referentes à importância de cada prática, com base nas opiniões de sete especialistas em CE; e (d) aplicação do protocolo a um empreendimento da construção civil. O protocolo foi inicialmente aplicado como um estudo piloto em um canteiro de obras o que possibilitou melhorias no documento. A versão revisada do protocolo foi então aplicada no mesmo empreendimento em que ocorreu a aplicação piloto, gerando dados que possibilitaram a avaliação do protocolo segundo sua utilidade. / The Lean Construction (LC) hás been introduced gradually in construction through practices such as loss control, quality management, and production and planning control. Given the spread of the LC in the construction industry, there is a need to measure the level of use of LC in the companies, which allows us to identify best practices and improvement opportunities. Thus, this study aims todevelop a protocol for the use of audit LC practices. This method was developed over four stages: (a) a literature review to identify LC categories of practice, based on the papers published in the Annual IGLC Conferences between 1993 and 2010, (b) sources of evidences definition to evaluate the use of each category of practice, (c) definition of weights referring to the importance of each practice, based on the opinions of seven LC experts; and (d) the protocol aplication in na construction site. The protocol was initially implemented as a pilot study on a construction site which led to improvements in the audit document. The revised protocol was then applied in the same project that occurred in the pilot application, generating data that enabled the evaluation of the protocol according to its usefulness.