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The Last Planner System (LPS) improves both design and construction schedule/programme predictability – work completed as and when promised. It is a system of inter-related elements – full benefits come when all are implemented together, over time. Based on simple paper forms, it can be administered using Post-it notes, paper, pencil, eraser and photocopier. A spreadsheet can help.
LPS begins with collaborative scheduling/programming engaging the main project suppliers from the start. Risk analysis ensures that float is built in where it will best protect programme integrity and predictability. Where appropriate the process can be used for programme compression too. In this way, one constructor took 6 weeks out of an 18-week programme for the construction of a 40 bed hotel. Benefits to the client are enormous.
Before work starts, team leaders make tasks ready so that when work should be done, it can be. Why put work into production if a pre-requisite is missing? This MakeReady process continues throughout the project.
There is a weekly work planning (WWP) meeting involving all the last planners – design team leaders and/or trade supervisors on site. It is in everyone’s interest to explore inter-dependencies between tasks and prevent colleagues from over-committing.
This weekly work planning processes is built around promises. The agreed programme defines when tasks should be done and acts as a request to the supplier to do that task. The last planners(that is the trade foremen on site or design team leaders in a design process) only promise once they have clarified the conditions of satisfaction and are clear that the task can be done.
A key measure of the success of the Last Planner system is PPC. This measures the Percentage of Promises Completed on time. As PPC increases. project productivity and profitability increase, with step changes at around 70% and 85%. This score is measured site-wide and displayed around the site. Weekly measures are used by the project and by individual suppliers as the basis for learning how to improve the predictability of the work programme and hence the PPC scores.