Construction Management as a field of applied science has escaped canonical definition. But one typical definition is that of Clough and Sears (1994) wherein Construction Management was defined as “The judicious allocation of resources to complete a project at budget, on time, and at desired quality”. This definition captures the essence of what inspired, drove, and guided practice and research in the Construction Management field. However, the failure and inability of the conceptual models of Construction Management (time-cost-quality tradeoff, work breakdown structure, critical path methods, and earned value) to deliver on the mantra of ‘on-time, at budget, and at desired quality’ is evident to practitioners and academics alike. For example, recurring negative experiences on projects, as manifested by endemic quality problems and rising litigation, indicate that construction projects are low efficiency systems (Koskela 2000). Analysis of project schedule failures by Ballard and Howell (2003) also indicated that “normally only about 50% of the tasks on weekly work plans are completed by the end of the plan week” and that most of these planning failures were possible to mitigate by contractors through an “active management of variability, starting with the structuring of the project - as a temporary production system - and continuing through its operation and improvement.”.
Koskela’s seminal 1992 report argued that Construction Management viewed projects as a transformation-based endeavor where the main focus is on transforming inputs to outputs with typically no management of the transformation process itself. He further stated that the mismatch between the conceptual models of construction management and observed reality on projects underscored the lack of robustness in the existing constructs of Construction Management and signaled the need for a comprehensive theory of production management in construction.
As a result of an outward-oriented search into the production paradigms that dominated and competed in the manufacturing industries, namely, craft, mass and lean production paradigms, and using the ideal production system embodied in the Toyota Production System, Koskela conceived a more overarching production management paradigm for project-based production systems. Koskela presented the ‘TFV’ theory of production wherein production was conceptualized in three complementary ways, namely, as a Transformation (T) of raw materials into standing structures, as a Flow(F) of the raw material and information through various production processes, and as Value (V) generation and creation for owners through the elimination of value loss (realized outcome versus best possible).
This tripartite view of production has lead to the birth of Lean Construction as a practice and discipline that subsumes the transformation-dominated contemporary construction management. In this author’s view, a profound implication of the TFV concept of production is that it changes the definition of Construction Management to the judicious allocation of resources to transform raw materials into standing structures while maximizing flow of material and information, and value to the customer.
Koskela and Howell (2002) have also argued that the management theory that underpins Project Management in general and Construction Management in particular was fraught with shortcomings– specifically as related to the planning, execution, and control paradigms – in dealing with project-based production systems. They suggested that planning-as-organizing, the action/language perspective, and the scientific experimentation model were critically needed elements to make Project Management theory more robust and contemporaneous. The Last Planner®System developed by Ballard and Howell (1994), is a production planning and control system that allows all team members to be active participants in the process and contemporaneously results in higher production unit performance and reliable work flow (hand-offs) between production units (see Ballard 2000 for more details).
Both conceptualizations, the TFV and the new PM theory, provide a solid intellectual foundation of Lean Construction as evident from both research and practice. Also recognizing that construction sites reflect prototypical behavior of complex and chaotic systems, especially in the flow of both material and information on and off site, Bertelsen (2003) suggested that construction should be modeled using chaos and complex systems theory and specifically argues that construction could and should be understood in three complimentary ways, namely, as a project-based production process, as an industry that provides autonomous agents, and as a social system.
The following figure depicts Lean Construction in terms of the new production and management theories, as well as the autonomous agents and social system view of Bertelsen (2003), and completes the entire façade of new paradigms that will govern Lean Construction research and practice for years to come (Abdelhamid 2004).
Thus far, in this discussion, no explicit definition of Lean Construction has been stated. Prior to doing that, we must talk about Lean Production. Following is a wonderful and authentic excerpt describing what Lean Production is. This description also captures the essence of Lean Construction. The excerpt is from a June 16, 2004 posting by Mr. Norman Bodek to the NW LEAN group ( http://www.NWLEAN.net/ ). Mr. Bodek is considered the godfather of the lean movement outside of Japan. He translated and published the writings of Taiichi Ohno, Shigeo Shingo, Seiichi Nakajima, and others who were the architects behind the Toyota Production System.
“…..Lean is fundamentally empowering all workers to be partners in your continuous improvement efforts. You ask them to make their work easier and more interesting. You challenge them to grow every day on the job. You ask them to cut costs, to improve safety, to improve quality and reduce the time line to deliver superior products and services to their customers. And you listen, listen, listen and learn from them. Of course, we focus on the wastes but we allow everyone to participate…………..There are two barriers to advancing lean manufacturing; one is just living in the old paradigm where we don't ask workers to be involved in creative problem solving. "Keep your brains at home," was the subliminal sign over the factory's front door." And secondly is the incredible resistance to change, the "not invented here syndrome." Yes, you can "always," find reasons not to do something. Most people are experts in this. There are those that like to play the "devil's advocate," and end up doing nothing………….Ohno and Shingo both loved to say simply - "Do it!" And then leave you the challenge to figure it out for yourself. They rarely ever had a cookbook approach for you. In fact, Ohno would never let anything be written down on how to do lean. He wanted it to be a system that allowed for constant change. Sure, their disciples created the Kaizen Blitz, which became a million dollar product for them. While others have created Six Sigma another million dollar product. Somehow we just resist change until everyone is doing it then we jump on the bandwagon”
Lean Construction is not a variant of Lean Production. Lean construction aims to embody the benefits of the Master Builder concept. Essentially, Lean Construction recognizes that desired ends affect the means to achieve these ends, and that available means will affect realized ends (Lichtig 2004).
While Lean Construction is identical to Lean Production in spirit, it is different in how it was conceived as well how it is practiced.
The common spirit flows from shared principles:
**A focus on delivering the value desired by the owner/client/end-user
**Whole System Optimization through Collaboration and systematic learning
**Allowing value to flow by systematically eliminating obstacles to value creation and those parts of the process that create no value
**Creating pull production
**Continual improvement/pursuit of perfection involving everyone in the system
Lean construction supplements traditional construction management approaches with: (1) requiring the deliberate consideration of material and information flow and value generation in a production system; (2) different project and production management (planning-execution-control) paradigms; and (3) a social science approach to the project organization and the individual.
So, what is Lean Construction? A simple, not simplistic, definition is that Lean Construction is a “way to design production systems to minimize waste of materials, time, and effort in order to generate the maximum possible amount of value (Koskela et al. 2002)”.
Designing a construction production system to achieve the value desired by owners and minimize the waste during the construction process itself is only possible through the collaboration of all project participants (Owner, A/E, Constructors, Facility Managers, End-user) at early stages of the project. This goes beyond the contractual arrangement of design/build or constructability reviews where constructors, and sometime facility managers, merely react to designs instead of informing and influencing the design.
"Lean Construction is a neologism, and draws upon the principles of project-level management and upon the principles that govern production-level management. Lean Construction recognizes that any successful project undertaking will inevitably involve the interaction between project and production management." (Abdelhamid 2007)
The Lean Construction Institute defines Lean Construction as a production management-based approach to project delivery -- a new way to design and build capital facilities….. Lean Construction is particularly useful on complex, uncertain and quick projects. It challenges the belief that there must always be a trade between time, cost, and quality…see ( www.leanconstruction.org)
The AGC of America Lean Forum defines Lean Construction as: A set of ideas, practiced by individuals in the construction industry, based in the holistic pursuit of continuous improvements aimed at minimizing costs and maximizing value to clients in all dimensions of the built and natural environment: planning, design, construction, activation, operations, maintenance, salvaging, and recycling…see www.agcleanforum.org
*A very important value of Lean Implementation is the state of being "Born Lean". This is the state of planning in the development phase of design and manufacturing. This is critical for the success and timeliness to the market if the lean philosophy is from the onset (J.Lars - Principal IE 2007)
Another definition, that of this author, is the following: A holistic facility design and delivery philosophy with an overarching aim of maximizing value to all stakeholders through systematic, synergistic, and continuous improvements in the contractual arrangements, the product design, the construction process design and methods selection, the supply chain, and the workflow reliability of site operations.
Basically, as a philosophy, Lean in the Construction Industry seeks the ideal state of constructing a facility that maximizes value to the client with no waste in execution by: 1) Achieving a state of early and common understanding of what is to be built among all project participants; and 2) doing the right things right the first time around.
Here’s a comparison between conventional CM and Lean Construction:
We know how to TRANSFORM materials into standing structures.
We (still) know how to TRANSFORM materials into standing structures.
We expect to have scope changes and design errors during construction, which will be field-engineered by construction teams.
We design product and construction process together to avoid design errors/omissions that lead to constructability issues.
We empower managers to be the SOLE planners.
We empower managers to be the FIRST planners of processes and phases and foremen and workers to be the LAST planners of operations.
We assume that reducing cost in one piece will reduce cost of the entire project – the whole is the sum of its parts
We treat entire project as a system and use Target Costing to achieve project cost reductions – the whole is more than the sum of its parts
We push for high local productivity mistakenly thinking that this is a way to achieve global efficiency.
We push for high system throughput which is the only way to achieve global efficiency.
We manage the process using schedules of cost-accruing elements – the ones on which progress payments are based.
We use schedules of cost-accruing elements as INPUT to the planning and control of site production operations.
We are guided by the time/cost/quality trade-off paradigm. We know from practice that you can only get one of the three, two if you’re lucky.
We challenge the time/cost/quality trade-off paradigm by removing the sources of waste in the design/production processes to promote better and more reliable WORKFLOW.
We don't plan or control site production operations unless we observe deviations in targeted time and cost - we wait until problems happen then react to get project back on track.
We plan and control site production operations to preempt cost-accruing elements from going off targeted time and cost. We make things happen.
We consider VALUE delivered to the owner when product performance is maximized relative to its cost – A Value Engineering (VE) approach.
We consider VALUE delivered to the owner when product value is increased (the facility better fulfills the true needs of the owner purposes) by managing construction process value – a Value-based Management (VBM) approach (Wandahl and Bejder 2003).
Abdelhamid (2007). Lean Construction Principles. Graduate class offering at
Abdelhamid, T., S. (2004). “The Self-Destruction and Renewal of LEAN CONSTRUCTION Theory: A Prediction From Boyd’s Theory”. Proceedings of the 12th Annual Conference of the International Group for Lean Construction, 03-06 August 2004, Helsingør, Denmark.
Ballard, G (2000). The Last Planner System of Production Control. PhD dissertation, University of Birmingham, UK.
Ballard, G. and Howell, G. (1994a). “Implementing Lean Construction: Stabilizing Work Flow.” Proceedings of the 2nd Annual Meeting of the International Group for Lean Construction, Santiago, Chile.
Ballard, G. and Howell, G. (1994b). “Implementing Lean Construction: Improving Performance Behind the Shield.” Proceedings of the 2nd Annual Meeting of the International Group for Lean Construction, Santiago, Chile.
Ballard, G. and Howell, G. (1998). “Shielding Production: Essential Step in Production Control”. Journal of Construction Engineering and Project Management, Vol. 124, No. 1, pp. 11 - 17.
Ballard, G., and Howell, G. A. (2003). “Competing Construction Management Paradigms.” Proceedings of the 2003 ASCE Construction Research Congress, 19-21 March 2003, Honolulu, Hawaii.
Ballard, Glenn (1994). “The Last Planner.” Northern
California Construction Institute Spring Conference,
Ballard, Glenn (2000a) , Ph.D. thesis,
Ballard, Glenn (2000b). “Lean Project Delivery Systems.” LCI white paper-8, (Revision 1)
Bertelsen, S. (2003a). “Complexity – Construction in a New Perspective”. Proceedings of the 11th Annual Meeting of the International Group for Lean Construction, Blacksburg, Virginia, USA.
Bertelsen, S. (2003b). “Construction as a Complex
System”, Proceedings of the 11th Annual Meeting of the International Group for
Bertselen, S. and
Koskela, L. (2002). “Managing The Three Aspects Of Production In
Construction.” Proceedings of the 10th
Conference of the International Group for Lean Construction,
Cain, C. T. (2003). ISBN 0-415-28965-3. 'Building Down Barriers-A Guide to Construction Best Practice'. A simple guidebook explaining supply chain management and lean thinking, primarily aimed at the demand-side client.
Cain, C. T. (2004b). 'Performance Measurement for Construction Profitability'. ISBN 1-4051-1462-2. A detailed action-learning guidebook aimed at supply-side construction firms (including trades contractors) explaining why performance measurement is the key to lean construction.
R. H. and Sears, G. A. (1994). Construction
Construction Management Association of America (2006). “Sixth Annual Survey of Owners.” FMI, Management Consulting, http://cmaanet.org/user_images/sixth_owners_survey.pdf (visited 6/11/06).
Howell, G. A. (1999). “What is Lean Construction.” Lean Construction Institute
Koskela, L. (1992).
“Application of the New Production Philosophy to Construction”.
Technical Report # 72, Center for Integrated Facility Engineering, Department
of Civil Engineering,
Koskela, L. (2000). An exploration towards a production theory and its application to construction, VVT Technical Research Centre of Finland.
Koskela, L. and Howell, G., (2002). “The Underlying Theory of Project Management is Obsolete.” Proceedings of the PMI Research Conference, 2002, Pg. 293-302.
L., Howell, G., Ballard, G., and Tommelein, I. (2002). “The Foundations of Lean Construction.” Design and Construction: Building in
Value, R. Best, and G. de Valence, eds.,
Kuhn, T. S. (1970).
The Structure of Scientific Revolutions.
Lichtig, W. (2005). "Ten Key Decisions to A Successful Construction Project." American Bar Association, Forum on the Construction Industry, September 29-30, 2005, Toronto, Canada.
Mastroianni, R. and Abdelhamid, T. S (2003). “The Challenge: The Impetus For Change To
Lean Project Delivery”. Proceedings of
the 11th Annual Conference for Lean Construction, 22-24 July 2003,
Sowards, Dennis, “5S’s that would make any CEO Happy,” Contractor Magazine, May 2004.
Wandahl, S., and Bejder, E. (2003). “Value-based Management in the Supply Chain of Construction Projects”. Proceedings of the 11th Annual Meeting of the International Group for Lean Construction, Blacksburg, Virginia, USA.