Level 1 (Management/Milestone level)
Level 1 corresponds to an executive summary of the program, also known as the Project Master Schedule (PMS). Typically, it comprises a list of the most critical milestones in the project, providing a concise overview. It serves as an effective means to communicate key project dates to company management. This level is valuable for listing contractual milestones, creating executive summaries, and assigning priorities among projects.
Used for: Listing contractual milestones, communication, summarizing the schedule in documents where only a snapshot is required, conversations about project priority to assess the project against other projects, project assessment.
Level 2 (Master)
A level 2 program consists of summary bars with the duration of the main products or phases, such as engineering, procurement, manufacturing, assembly, and commissioning. It is a way to consolidate one or more plans into a simple one to create a global summary (Summary master Schedule SMS). It should include all the information from level 1, but with a higher level of detail.
Used for: Project management, executive reporting, and management reporting of project activities.
Level 3 (Project level)
Level 3 schedule summarizes detailed planning (Level 4) and feeds into Level 2. It breaks down each product or phase into summary activities with logical relationships. It is commonly used during the tender phase of a project, demonstrating the work to be performed, dates, and basic work sequence. Level 3 schedules are developed using specialized software, mainly MS Project, allowing calculation of the critical path.
In some cases, a baseline can be established after some time after signing the EPC contract, with the aim of having the engineering advanced and thus being able to carry out a more precise level 3 program.
Used for: Input to monthly reporting, contractual documentation, tender documents, creating a schedule framework for sub-contractors, establishing the critical path, consolidating level 4 schedules for project control.
Level 4 (Control/Execution level)
The Execution Schedule is a detailed work plan specifying tasks to deliver the project on time. Managed by the project delivery team and subcontractors, it enables daily and weekly activity management, resource coordination, and serves as a basis for measuring progress and performance. Level 4 schedules are essential for monitoring and controlling work activities and should be maintained in a manageable size.
The developed schedule may be for the entire project or part, depending on the size of the project and the complexity of the work to be performed. It is important to keep each schedule a reasonable size that can be easily managed, updated, and validated.
Used for: Daily project management, detailed task tracking, detailed progress control, look ahead report, float analysis, delay analysis, Project histogram (early-late curve)
Level 5 (Detail Level)
A level 5 schedule is a detailed breakdown of each level 4 activity. Reserved for critical or highly specialized tasks requiring hourly or daily planning. For example, software transition plans are often created hour by hour so that the team knows exactly what actions to take for the migration or to manage shutdowns and maintenance activities of large industries (blast furnaces, refineries…).
This is, therefore, a level that is not usually necessary for most projects. Primavera P6 offers the possibility of performing a more detailed breakdown of existing activities by using “Steps”, which can be very useful for intricate planning scenarios.
Used for: manage critical or extremely complicated activities, organize in a very detailed way the coordination between contractors.
Bullet points
- Levels are conventionally developed from the highest to the lowest and updated in the reverse order, starting from the lowest level to the highest.
- Levels 1 and 2 are normally developed as part of the prior feasibility study to determine the viability of the project.
- The Level 3 schedule is initially developed as a general description of the activities to be carried out. For some projects, the Level 3 schedule evolves into a Level 4 schedule to coordinate the execution of the works. On larger projects with multiple contractors (Level 4 schedules), the Level 3 schedule might be used as the overall integrated schedule for the project.
- Every big project requires a Level 4 schedule for daily coordination of work. It’s crucial, however, to ensure that the overall size of this schedule remains manageable and aligns with the complexity of the work.
- Level 5 planning is reserved for very specific cases where highly detailed schedule is imperative.