The Last Planner System (LPS) is a project management approach used primarily in the construction industry to improve planning, scheduling, and overall project performance. It is part of the Lean Construction methodology, which aims to reduce waste, increase efficiency, and enhance collaboration among project teams. The core idea behind the Last Planner System is to engage the “last planners” in the decision-making process, particularly those workers and supervisors who are responsible for executing the work on the ground (e.g., field supervisors, foremen, and crews). This system helps improve the reliability of the schedule and creates a more predictable flow of work.
Key Principles of the Last Planner System (LPS)
- Collaboration and Engagement:
LPS emphasizes collaboration between all project stakeholders, including owners, contractors, subcontractors, suppliers, and field crews. The system encourages input from the people who are actually doing the work, because they are best placed to assess what is realistically achievable and identify potential issues before they arise. - Planning Backwards:
One of the unique aspects of the Last Planner System is its focus on pull planning. The idea is to plan backwards from the desired project outcomes, ensuring that the work flows smoothly without delays, and resources are available just in time. This approach contrasts with traditional project planning, where schedules are often pushed forward without enough consideration of actual capacity and constraints. - Continuous Improvement:
The Last Planner System uses data and feedback from actual work performance to continuously improve planning processes. By regularly reviewing how well plans were followed and identifying reasons for deviations, teams can refine their approach and make adjustments for future work. - Reliability and Predictability:
The main goal of the system is to improve the reliability of the schedule. By involving the workers who will actually perform the tasks, the planning process becomes more grounded in reality, making the project’s outcomes more predictable. The system focuses on planning for reliability rather than simply adhering to an arbitrary timeline.
The 5 Levels of Planning in the Last Planner System
The Last Planner System operates on several levels of planning, starting with high-level planning and then progressing down to the detailed execution level. These levels are:
- Master Planning (Long-term Vision):
The high-level project plan that establishes major milestones and key deliverables. This stage typically focuses on broad timelines and major construction phases but is flexible and subject to change. - Phase Planning (Medium-term Detail):
Once the broad master plan is in place, the project is divided into phases. These phases are planned in more detail, identifying critical tasks, sequencing, and resource requirements for each phase. This is where teams begin to schedule the major portions of work based on availability and dependencies. - Look-Ahead Planning (Short-term Focus):
Look-ahead plans cover the next few weeks and are continuously updated. They focus on tasks that need to be completed in the near future. The last planners work to identify tasks that could potentially cause delays, ensuring resources are available and that the flow of work will proceed smoothly. - Weekly Work Planning (Tactical Level):
At this level, the focus is on the weekly planning cycle. The team conducts a weekly meeting to plan in detail the tasks that can be completed in the upcoming week, ensuring that everything needed for the work (materials, labor, etc.) is in place. Each task must be planned in a way that it is achievable given the current site conditions, crew availability, and material delivery schedules. - Daily Execution:
The last planners (typically the foremen or crew leaders) check daily to ensure that work is being carried out according to the plan. They also adjust plans if necessary, based on the realities of the day’s work. Daily feedback is critical to ensure the project stays on track and any issues can be addressed immediately.
Key Components of the Last Planner System
- Pull Planning:
Pull planning is a technique used to engage all parties in the scheduling process. Work is “pulled” forward based on the needs of the next phase, rather than being “pushed” by external deadlines. Teams work backward from the project’s end date or milestones to create a realistic schedule, identifying the necessary tasks that must be completed to reach the desired outcome. - Make Work Ready (MWR):
This concept ensures that all tasks are fully prepared before they begin. It means confirming that all materials, resources, drawings, and information are available and that tasks can be carried out as planned without unnecessary delays. - Commitment Planning:
The key element of LPS is getting commitments from those doing the work (the “last planners”) to ensure tasks can be completed as scheduled. The last planners commit to specific tasks based on their realistic assessment of their ability to perform the work, ensuring that work is only scheduled if it can truly be completed within the required time. - Percent Plan Complete (PPC):
The Percent Plan Complete (PPC) is a metric used to measure the reliability of the schedule. It is calculated by tracking how much of the planned work was actually completed within the specified time. PPC helps to identify areas where the team may be over-committing or underperforming and provides a benchmark for continuous improvement.PPC=Number of Tasks Completed On Time / Total Number of Tasks Planned×100 - Weekly and Daily Huddles:
These short meetings (often called “huddles”) involve the project team to review the weekly and daily tasks. During these huddles, progress is reviewed, obstacles are identified, and corrective actions are discussed. This keeps everyone aligned and focused on the immediate goals of the project. - Feedback Loops:
Continuous improvement is a key element of the Last Planner System. The team regularly assesses how well the work is being completed compared to the plan. This feedback is used to adjust the planning process for future tasks, ensuring that the project continually progresses more smoothly and efficiently.
Benefits of the Last Planner System
- Improved Schedule Reliability:
Since the Last Planner System incorporates feedback from the workers who actually execute the tasks, it tends to produce more realistic and reliable schedules. This reduces delays and improves the predictability of project timelines. - Increased Collaboration and Communication:
LPS fosters greater collaboration and open communication between different project stakeholders, including owners, designers, contractors, subcontractors, and the crews doing the work. This collaborative approach helps identify potential problems early and find solutions quickly. - Reduced Waste:
By improving scheduling accuracy and reducing delays, the Last Planner System helps minimize waste in terms of time, labor, and materials. It also helps prevent overproduction or underproduction of resources, reducing idle time and unnecessary costs. - Empowerment of Workers:
The system gives workers and supervisors more control over the planning process, which boosts morale and accountability. When workers are actively involved in creating the schedule, they are more likely to meet their commitments and take ownership of their tasks. - Continuous Improvement:
Through metrics like PPC and regular reviews, the team can continuously improve its planning processes. Lessons learned from past projects or tasks are incorporated into future work, creating a culture of ongoing improvement. - Reduced Overproduction:
Overproduction, or the tendency to schedule too many tasks or too much work in advance, is minimized with the pull planning approach. This leads to better resource allocation and reduces bottlenecks in the workflow.
Challenges of the Last Planner System
- Initial Resistance:
Adopting the Last Planner System can require a cultural shift, particularly if team members are used to a traditional project management approach. Some stakeholders may resist the change or find it difficult to embrace the level of collaboration and commitment required. - Time and Resource Intensive:
The system requires significant upfront time and effort to engage all team members in detailed planning and coordination. Regular meetings, reviews, and adjustments can be resource-intensive and may add overhead to the project. - Data and Monitoring Requirements:
To be effective, LPS relies on data to track performance (such as PPC), which means accurate data collection and tracking are essential. This can require additional tools, software, or personnel to manage and analyze data. - Need for Skilled Facilitation:
Successful implementation of LPS requires skilled facilitators who can effectively manage the collaborative planning process, resolve conflicts, and ensure that team members are fully engaged and committed.
Conclusion
The Last Planner System is a lean construction methodology designed to improve the reliability of project schedules, enhance collaboration, and minimize waste. By involving the last planners—the individuals responsible for executing the work—in the planning process, the system creates more accurate and achievable schedules. Through continuous feedback, commitment planning, and regular coordination, LPS helps teams deliver projects more efficiently, on time, and within budget. While it requires significant commitment and effort, its benefits in terms of schedule reliability, reduced waste, and improved team collaboration make it a valuable tool in modern construction project management.