The ever-increasing level of digitization, automation and autonomation will change construction. And this will inevitably change the nature of Lean Construction. Ultimately, Lean Construction will result in the ultra-efficient construction site. We don’t yet know what that is, but we know that we need it! The Future of Lean Construction describes the path to the ultra-efficient construction site based on five Lean Eras. New disruptive technological change is required for the upcoming eras. The five Lean Eras are discussed in the following sections.

THE ANALOG APPROACH HELPS TO UNDERSTAND THE METHODOLOGICAL APPROACH

Analog Lean began in the early 2000s, or maybe even earlier. In addition to adapting common practices from Lean Production, there are methodologies that have been developed specifically for the construction site. The three most commonly used methodologies are:

1. Last Planner System (LPS®)
2. Takt Time Planning and Takt Time Control (TTP&TTC)
3. Lean Construction Management (LCM®)

The overall goal of all Lean Construction methodologies is to make work visible: Visualization makes work transparent – and transparency allows risks and challenges to be identified early. The result is processes that are stabilized and become steadily more permanent. This reduces the ‘mother of all waste’ in construction projects, namely schedule deviations.

THE DIGITAL ERA IS DIGITIZING THE LEAN APPROACH

There have been increased attempts to digitize and disrupt the analog methodologies that are based on sticky notes. The coronavirus pandemic and the associated restrictions were a global catalyst for development. The digitization of Lean approaches enables the collection of real-time project data including productivity rates, meeting minutes, process sequences and process durations, and more. The potential is there, but currently the primary focus is on communication and real-time collaboration. This means that solutions that digitize the Last Planner system try to recreate the emotion of the Lean room both virtually and digitally. While spreadsheets have always been used for takt time planning, a digital concept had to be created for the Last Planner system. Nevertheless, more and more software solutions are popping up for takt time planning itself that simplify and automate the creation of the takt schedule. This results in a hybrid approach to the review at daily, weekly and monthly Lean meetings: A digital tool for data acquisition with the meeting taking place in person in front of an on-site screen.

THE SMART ERA INTERCONNECTS HUMANS, MACHINES AND MATERIAL

Data, data, data! Tens of billions of terabytes of data are generated on construction projects worldwide every day. The systematic collection and analysis of this data a huge challenge for the construction industry. The Smart Era is essentially about the interconnectedness of people, machines and materials. While during the digital Lean Era data was generated and collected by entering it into the system, the vision of Smart Lean Construction is to generate and network data passively. One possible scenario for Smart Lean Construction is the networking of tradespeoples’ tools and materials with the takt schedule in the Building Information Model. This would allow progress to be seen in real time. In future, many companies in the construction industry will have the ability to collect project data in a structured way during ongoing site operations. But only those who are able to quickly evaluate the data and make improvements will remain competitive.

THE AUTONOMOUS ERA INCREASES FOCUS ON MACHINES

In the era of Autonomous Lean Construction, the construction industry will have been completely disrupted. There are hardly any blue-collar workers left on the construction site – work is performed by machines, robots and/or 3D printers. The construction project is more about supply than execution. And this results in operational changes: Lean Construction becomes very similar to Lean Production. Optimization at the level of the human being, trade chains and contractors decreases, while optimization at the level of the customer cycle (takt time), the machine and the interface to the suppliers increases. It may even be that during this era, autonomous lean construction reverts temporarily to analog. Shopfloor cascades in the construction site, integrated into the corporate unit, with a target development process (like Hoshin-Kanri) on the strategic level, will no longer be unthinkable. The current interface between the Lean Enterprise and the Lean Project will dissolve.

THE ULTRA-EFFICIENT CONSTRUCTION SITE. WE DON’T KNOW WHAT IT IS, BUT WE KNOW WE NEED IT

The vision of every Lean factory is to become a synchronous factory. The ultra-efficient construction site can probably go in this direction, resulting in a synchronous construction site with no errors and with processes that are fully digitized, smart and autonomous. One thing is certain: Project complexity will continue to increase. Sustainability requirements, increasing cost pressure and the need for ever shorter project cycles mean that, despite all the technology, construction will not get simpler. The challenges are becoming more complex and the issues that need to be resolved by engineers and technicians will become increasingly difficult. Essentially, it will be a matter of using all available technology to manage projects across the entire planning framework. The need for holistic process systems that are able to sustain and improve this synchrony in a structured way during implementation will take Lean to another level – and possibly end up being even more disruptive. The visualization and processing of project-related data streams, as well as smart connections between dependencies and influencing variables, will lead to autonomously created project and production plans. Through artificial intelligence and real-time data, the project will constantly learn. Perhaps the project will then be the platform that does everything autonomously. We don’t know. But we should position ourselves today so that we are able to change for the future.