Now that we understand what a WBS is and the importance it plays to our project, let's review the key techniques, guidelines, and principles in building an effective WBS.
In general, the process of breaking down work is something we do frequently and is a straightforward logical endeavor. However, there are frequently two common challenges in the WBS development process.
Major deliverables should come from the project definition document and are likely second-level WBS elements.
There is no one way to organize a WBS. It should be organized in a manner that emphasizes the most important aspects and that best communicates the entire scope of the project to your stakeholders.
To start the work decomposition process, think about the following:
To continue the work decomposition process, think about these questions:
Guidelines for Effective WBS
Here are a few "guidelines" regarding the development of the project WBS that you will want to keep in mind:
WBS should always be defined at least one level lower than what is required for management reporting purposes. This allows you to better identify the source of any issues or variances.
In general, the more detail in the WBS, the more accurate the work estimates and the better level of control. However, there is a balance. Too much detail and you will incur excessive costs performing data collection, tracking, and reporting. Too little detail and you incur higher risks and be unable to effectively manage.
The level of depth (granularity) for the work package level in a WBS (lowest levels) will vary. It depends on what level of detail the project manager needs for effective management and control of the project.
In a program, or on large projects, the work package level may represent efforts in the hundreds of hours. In these cases, it is expected that the teams assigned to these work packages (or subprojects) will define the detail activities and tasks needed to complete the work package. From a practical standpoint, these teams should develop their own WBS that can then be rolled-up into the master WBS.
Most troubled projects have WBS elements that are too large. If each lower level element should be completed within the standard reporting period (every week or every two weeks), it is much easier to track actual progress and to take any corrective actions.
Knowing When to Stop
The other aspect of WBS development that creates frequent uncertainty is knowing when to stop. To determine if you have enough detail in your WBS, review these questions for each lower level item:
You will read about common rules of thumb for the proper size of work packages. The most common rules are 8/80 and 4/40, which means no task should be less than 8 hours or more than 80 hours, or in the case of 4/40, it would less than 4 hours or more than 40 hours.
These are solid guidelines, but not rules.
The most important thing to remember is to size the work package to the level you need for effective management and control. Again, setting the maximum size to correspond to your reporting period is an excellent idea.
The importance of the WBS cannot be over-emphasized. Since the correctness and completeness of the WBS has a direct impact on how well we determine our resource needs, estimate the work efforts, and properly sequence the work, it is the foundation that drives our schedule and most of our planning efforts.
The Absolute Minimum
At this point, you should have a solid understanding of the following:
The map in Figure 6.4 summarizes the main points we reviewed in this chapter.
Figure 6.4. Developing a work breakdown structure overview.
Part i. Project Management Jumpstart
Project Management Overview
The Project Manager
Essential Elements for any Successful Project
Part ii. Project Planning
Defining a Project
Planning a Project
Developing the Work Breakdown Structure
Estimating the Work
Developing the Project Schedule
Determining the Project Budget
Part iii. Project Control
Controlling a Project
Managing Project Changes
Managing Project Deliverables
Managing Project Issues
Managing Project Risks
Managing Project Quality
Part iv. Project Execution
Leading a Project
Managing Project Communications
Keys to Better Project Team Performance
Ending a Project