How to Use Percent Plan Complete to Deliver Projects Faster

Percent Plan Complete (PPC) is a key metric in the Last Planner System?. If you're not familiar with the Last Planner System, you can read a detailed description on the Lean Construction Blog here.

PPC measures the percentage of tasks planned for a week that a project team completes on the planned day. This straightforward calculation helps project teams track weekly trends and planning reliability. Reliable weekly plans ensure coordinated work across disciplines, minimizing interruptions and enhancing productivity.

However, not all PPC numbers are equal. The quality of a weekly work plan significantly impacts the calculation. Quality depends on three factors:

1. Task Definition: Define tasks as measurable amounts of work that a person or crew completes in a single shift. Plans with multi-day tasks are less precise and may show higher PPC.
2. Tasks Anticipated: This measures the percentage of tasks completed from the planners' weekly work plans. Projects that focus on a limited number of basic tasks may appear to have a high PPC, which can be superficial.
3. Tasks Made Ready: This measures the percentage of planned tasks with all resources available at the start of work. Tasks not ready should not be on the weekly plan to maintain reliability and productivity.

To use PPC for faster project delivery, follow these steps:

1. Correct Task Definition: Each task on the weekly plan must be measurable and completed in one shift by a person or crew. Tasks must be sound, with preceding work completed as planned.
2. Anticipate Tasks: Include a reasonable percentage of tasks in the weekly plan based on project type. For example, new apartment building project teams can predict most tasks, while historic renovations may have more unplanned tasks.
3. Ensure Tasks Are Ready: Use a constraint management process to ensure all tasks can start when scheduled. Aim for 100% Tasks Made Ready, considering possible acceleration in productivity.

By following these steps, measuring PPC becomes a meaningful practice for faster project completion. It does so by setting the stage for learning and improvement.

The Last Planner System advises tracking the causes of plan variances, including early task completions. Teams use Pareto charts to identify common causes and test interventions. Few teams engage in this variance reduction practice.

I recommend teams go deeper with this practice. Daily, assess and recommend interventions for plan variances identified in daily huddles. Capture these in a daily report for all weekly planners. This process promotes rapid learning and planning improvements.

Aim to achieve 100% PPC quickly, setting a high standard for planning reliability. As PPC nears 100%, communication, readiness, and handoffs improve, boosting productivity and schedule gains. Advanced teams should consider defining tasks in half-day increments to learn from plan variances and workflow studies at an expert level.