What is Lean Construction? Methodology, Principles, & Best Practices of Lean Building

Definition of Lean construction

Lean construction represents a new approach to delivering construction projects. It is a project management-based approach that prioritizes companionship and collaboration throughout the project realization process.

Construction projects are highly complex processes involving multiple parties, dozens of participants, and massive budgets. The construction industry is also known for its overall inefficiency, as it is a relatively conservative industry that has struggled to improve its results using modern technologies.

This inefficiency leads to on-site deaths and injuries, missed deadlines for project completion, and project overruns. Many of these shortcomings are attributable to the general outdated structure that many industry players use today.

Lean construction can resolve many of these issues simultaneously, emphasizing collaboration between departments while minimizing waste and maximizing the value of the project to stakeholders. The end goal of lean construction is to create a system that releases the results of the work of one process to the next with no delays or issues.

One of the main reasons why the definition of “Lean construction” might look somewhat broad is the fact that constant evolution and improvement is in the very nature of the Lean approach, which makes it challenging to define the capabilities of the approach as a whole.

History of Lean construction

The most commonly used starting point in the history of the Lean methodology is the early 20th century and the creation of Henry Ford’s Model T automobile.

The construction of the Empire State Building in 1929–1930 is another famous example of Lean construction management. This is the first example in the construction industry, and its performance results remain impressive to this day. The building was built within budget and completed before the schedule. At their most effective, the construction team working on the Empire State Building managed to build a floor of the building per day.

Another version of the Lean project approach was popularized after WWII by Toyota in one of the first examples of lean project management in mass production. The technology has evolved considerably over the years, but it has never gained much popularity for multiple reasons that will be discussed later. There are still multiple examples of how Lean construction yields more effective results than traditional approaches, however.

For example, the T-30 Hotel in China was built using Lean production methods. It took only 15 days to create a 30-story building from the ground up with multiple unusual features such as extensive earthquake resistance.

Concept of the MacLeamy curve

The idea of a Lean approach to the construction industry has existed for a while. In 2004, Patrick MacLeamy produced the well-known graphic that has come to bear his name: the MacLeamy curve.

There are multiple interpretations of this curve in different resources, but the result is the same: a great many project design changes are performed when the cost of each change is extremely high.

This necessitates a completely new approach to the entire process of construction project planning. Lean construction is one such approach which makes it possible to perform design changes a lot earlier and keep the cost of each change much lower in comparison.

Advantages of Lean construction

The potential advantages of Lean construction project management are numerous, even if integrating the framework might be somewhat challenging. Some of the most significant advantages of Lean construction are:

• Much stricter cost control. Expenses are easily kept at a lower level due to the fact that overhead costs, material costs, and labor costs are applied only to the value stream.
• Improved team collaboration. Lean construction relies a lot on collaboration between departments and product teams, including different project phases, from start to finish. Just-in-time availability and the avoidance of costly mistakes are just some of the many advantages that heightened collaboration can offer in construction projects.
• Higher customer satisfaction. Even though the construction industry is largely used to budget overruns and missed deadlines, this does not mean that potential clients do not wish for their projects to be completed on time, if not earlier. Delivering projects under budget and within deadlines is a massive advantage to any company in the competitive field of construction.
• Better resource utilization. Because Lean construction focuses on providing the greatest possible value to the customer, the overall cost of each project is dramatically reduced. Construction companies’ constant focus on the most crucial project elements also improves their efficiency.

Lean construction and small businesses

Lean construction may seem like a very challenging concept that would be difficult to implement in most cases. This assessment holds a lot of truth, since Lean principles are dramatically different from what most companies in the industry are used to, and the number of changes is quite significant for many companies.

At the same time, it may seem that the concept of Lean construction would be even more difficult for small companies to handle, since even the most prominent enterprises struggle with changing their existing processes so much.

However, the actual situation is quite different. Most smaller companies and businesses will find it easier to adopt Lean construction principles, and there are several reasons for this:

• Small businesses often use regular changes and continuous improvements to stay relevant in this highly competitive industry. As such, adding Lean construction to this mix does not create a change that is too big for these companies specifically.
• Since Lean principles often affect many of a company’s core principles and workflows, smaller companies might find it easier to adapt to new changes due to the fact that their existing processes are not as complex and distributed throughout multiple departments and stakeholders (as the situation might be for a large construction business).

In fact, the principles of Lean construction are becoming increasingly popular among small businesses. Charlie Garbutt has written an entire book called Lean Construction: A Small Contractor’s Journey. The book does exactly what its title suggests: it explains how a small contracting company improved its results by introducing Lean construction into its existing workflows and processes.

Lean construction and BIM

Lean construction can also be used in combination with other techniques and methodologies. For example, integration with BIM can be used to get the best of both approaches within the same company. Some of the most prominent examples of the synergy between BIM and Lean are:

• BIM makes it easier for Lean construction to analyze and improve its results by providing a clear and detailed digital footprint that can be used in the analysis.
• Lean construction attempts to address all the different forms of waste, while BIM improves how Lean principles address physical waste, including more specific material orders, a smaller amount of  rework that generates waste, and so on.
• BIM enhances Lean construction’s attempt to implement a collaborative culture. It can serve as a centralized platform for data exchange, employee communication, and more.
• Scheduling can be extensively optimized by combining Lean construction’s “pull” planning approach with BIM’s extensive project visualization.
• Lean construction emphasizes maximizing the project’s value to the client, and BIM can contribute to this by performing scenario analysis and helping stakeholders with decision making.
• Both BIM and Lean methodologies attempt to avoid both waste and rework by focusing on performing all processes on the first try. BIM can simulate potential outcomes to test various scenarios, offering the ability to resolve issues before jeopardizing the state of the project.
• The combination of Lean construction methodologies and BIM tactics combines tight control over task execution with detailed planning for every task. BIM can support Lean methods by providing detailed visualization of complex sequences and schedules, making them easier to manage and explain to different stakeholders.

Principles of Lean construction

Lean construction relies on six principles, the Lean Construction Institute (LCI) Tenets:

The Lean Construction Institute is a nonprofit organization that has been working for several decades toward improving the construction industry by applying Lean principles to existing processes. It was founded in 1997 and offers multiple helpful resources for industry professionals who are interested in implementing Lean construction practices in their workflows.

• “Respect for People”

The overarching goal of the entire process is to connect every other principle in a single framework. The biggest goal of the Lean construction concept is to promote trust and cooperation between project participants while achieving the best possible results for the client. These goals can be accomplished only by promoting trust between project participants and resolving the well-known lack of trust between stakeholders in most construction projects.

• “Optimize the Whole”

The traditional approach to construction assumes that most project teams do only their own work and nothing else. However, attempting to bring in different project participants for more involvement in other phases of construction brings many more advantages to everyone involved than the traditional approach. A friendlier and conflict-free environment is necessary to get the most out of the collaborative idea of Lean construction.

• “Focus on Flow”

No one says that Lean construction is easy. It is much stricter about every project participant doing their job to the fullest. Due to the way the Lean principles work, a single process disruption may be a significant detriment to several subsequent project teams since they are connected to one another in the same project realization process. The “flow” of the entire process from start to finish is very important to the overall success of the construction project.

• “Continuous Improvement”

Lean construction is an active process and not a one-and-done situation where everything is at its best from the start. Unfortunately, that is not how modern processes work. Constant analysis and improvement are necessary for existing construction processes to stay relevant and effective for all current and future project realization processes.

• “Generate Value”

Lean construction’s concept of value can be somewhat challenging to understand. It is a collection of almost every other element of Lean procedures at once: improved collaboration, continuous enhancement of the process, constant communication with the client, and so on. “Bringing in value” can be directly translated as “adhering to Lean construction principles as much as possible.”

• “Eliminate Waste”

Waste is surprisingly common in the construction industry, mostly due to the sheer scope of the majority of projects in the industry. However, the current level of waste dramatically affects the performance of construction projects while also being extremely disrespectful to stakeholders and clients.

There are many different iterations and personal views on the principles of Lean construction, but most are generally very similar to the LCI’s version.

Waste elimination and Lean construction

Multiple types of waste are recognized in the context of Lean building practices. This is a significant topic on its own, which is why it deserves a separate category. Most companies practicing Lean construction recognize eight types of waste. For convenience, there is even an acronym for them: DOWNTIME.

• Defect – any action that requires rework due to not being done correctly the first time around.
• Overproduction – a situation in which a task is completed earlier than required and the next task on the schedule cannot be started yet.
• Waiting – the complete opposite of the previous event. This happens when workers are ready to perform a certain task on time but cannot do so because the previous process in the chain has not been completed yet.
• Not utilizing talent is the inability to match each worker’s skills and talents with the appropriate job, wasting knowledge and potential at the same time.
• Transport – can describe the unnecessary transmission of information or a situation in which materials or labor are delivered to the site before they are needed there.
• Inventory – everything that cannot be used immediately is considered excess inventory that deteriorates, requires excessive storage, and expands the budget without the need to do so.
• Motion – any movement that is not necessary for the construction process, including excessive distance between tools, materials, and workers.
• Excess Processing – any feature or activity that is added to the construction project but has no real value to the client. It is not uncommon for excess processing to appear as a result of the removal of other types of waste.

Since eliminating all forms of waste is one of the main goals of Lean construction, it is easy to understand why this classification is so long and thorough. Lean construction tools also attempt to improve sustainability in the more traditional sense, with better use of construction resources, greater energy efficiency, lower emissions, sustainable construction techniques, and more.

The term “waste” as regularly used in Lean construction is much broader than the physical waste construction companies generate during the construction phase. It also covers wastage of manpower, time, and other resources that the traditional construction approach generates regularly throughout the entire project lifecycle.

What is the Lean construction philosophy?

Adopting a Lean construction philosophy can be challenging. Many companies, large and small, resist new ideas or changes by default. This effect is even worse in the construction industry, which is known for its conservative approach to many tasks.

As such, the first step is to choose the person who will champion the change (with the full backing of management). Being able to persuade others of the various benefits of the Lean philosophy is a requirement here.

There also needs to be a reason that everyone understands, such as a crisis in the industry as a whole or a significant issue in a recent project caused by the outdated approach to the construction process.

Immediate results and visible activity are necessary in the early days of the adoption of the Lean philosophy. Selling employees on the benefits and advantages of the new approach is necessary to avoid a backlash among staff. Slowing down after the initial implementation phase is also not a good idea, either, since the entire philosophy of the Lean construction approach is continuous improvement across the board.

That is not to say that this massive change is suitable for every company from the get-go. There are many companies that may already use some elements of the Lean approach in their workflows without knowing it. However, some of the most essential elements, such as a deeper understanding of the client’s requirements, are still necessary for everyone to build a deeper relationship with the client and improve the company’s reputation.

The concepts of efficiency and productivity are not particularly common in this industry, and plenty of organizations still operate with outdated beliefs and workflows. These companies are the prime targets for implementing the Lean construction philosophy due to the sheer volume of advantages that the change in the approach to construction can bring.

Types of contract that support Lean construction

The number of contract forms that support Lean construction in some way is growing regularly. Some examples of standard contract forms also support Integrated Project Delivery (IPD) as an alternative. IPD is a relatively basic agreement that aligns project objectives with the interests of all participants while promoting transparency, cooperation, and so on.

There are at least five different forms that can be used right now:

• Integrated Form of Agreement, or IFoA. This contract form explicitly uses multiple BIM and Lean construction principles in its structure. It was first developed to be used in various healthcare-oriented projects in California, but it has spread around in recent years.
• ConsensusDocs300 is technically an addendum to IFoA. It is a tri-party agreement that also covers topics such as BIM usage, the implementation of IPD, Green Building, and more.
• PPC2000 is a standard form of contract in the UK that also supports Lean construction principles. It was initially published by the Association of Consulting Architects.
• Job Order Contracting is a long-term agreement to create a collaborative and common data environment and promote the use of lean construction principles across the board. JOC includes full auditability, complete regulatory compliance, collaborative cloud technologies, the proactive integration of new technologies, and an explicit focus on bringing value to all participants and clients.
• Document C191TM (2009) is a standard multi-party agreement form created by the American Institute of Architects. It includes the use of IPD in projects and the creation of an agreement between contractors, architects, and owners regarding design, construction, and commissioning for a particular project.

Conclusion

Lean construction can bring tremendous advantages to companies that are willing to commit to using the philosophy. On paper, it looks like a single solution to multiple long-running issues in the construction industry as a whole, such as missed deadlines, budget overruns, the generation of massive amounts of waste, lack of cooperation between stakeholders, and so on.

For example, this article discusses implementing Lean construction techniques to minimize risk in construction projects. The article also uses the specific example of an industrial project in Egypt for its testing. The bulk of the article revolves around the introduction of the Last Planner System, a tool that streamlines production planning procedures by making them more flexible and formal.

The tool helps minimize waste using detailed forward-looking scheduling and assignment-level planning. Introducing the Last Planner System to the existing weekly work plans reduced the total project time by 15.57% (calculated using two metrics: Percent Plan Completed and Percent Expected Time-Overrun).

At the same time, implementing Lean construction principles and ideas can be extremely challenging, mostly because of the entire industry’s resistance to change. A lack of understanding of how advantageous new technologies and solutions can be only worsens this resistance across the board.

It is our hope that this article will help companies and users understand how advantageous Lean principles can be if they are implemented correctly.