The work breakdown structure (WBS) is a deliverable-oriented hierarchical decomposition of the work to be executed by the project team to accomplish the project objectives and create the required deliverables.
The WBS organizes and defines the planned work tasks of the project. How detailed should it be and how many levels should it have? The obvious answer is as detailed and as low as it can be scheduled, estimated, monitored and controlled, or it won’t be effective. You can have the most detailed WBS in the world but if it cannot be managed it will not work. So, depending on the project scope and project team (which include the project manager) it should be “just right”.
How do we get to an effective WBS?
o The project team must define the tasks
Project managers manage projects, the team performs the work and produces the deliverables; they are the ones who really know what needs to be done. Ask the team to define the activities needed to produce each deliverable (top-down approach) and then perform a peer review of the activities definition to ensure they are complete (bottom-up review)
o Rolling wave planning approach
Allows to, progressively, define tasks to be done in the future at a higher level while near term tasks are defined at their lowest level so work can start on them. As future tasks come closer they are redefined to their lowest level
o Stay within project scope
Ensure that deliverables and tasks to produce them are exactly what the project asks for. Producing more and/or better without stakeholders’ approval is nice but counterproductive
A simple example of a good WBS for a house painting project:
o Clean walls (this is a deliverable)
– Rent pressure cleaner (this is an activity/task)
– Pressure clean walls (this is an activity/task)
– Return pressure cleaner (this is an activity/task)
o Paint walls (this is a deliverable)
– Select paint color (this is an activity/task)
– Purchase paint (this is an activity/task)
– Purchase paint tools (this is an activity/task)
– Paint walls (this is an activity/task)
A simple example of a bad WBS for a house painting project:
o Clean walls (this is a deliverable)
– Inspect which walls need cleaning (this is an activity/task)
– Find best price for renting pressure cleaner (this is an activity/task)
– Rent pressure cleaner (this is an activity/task)
– Pressure clean walls (this is an activity/task)
– Return pressure cleaner (this is an activity/task)
o Paint walls (this is a deliverable)
– Find best price for paint (this is an activity/task)
– Look at different paint brands, types, shines and colors (this is an activity/task)
– Select paint brand (this is an activity/task)
– Select paint type (this is an activity/task)
– Select paint shine (this is an activity/task)
– Select paint color (this is an activity/task)
– Purchase paint (this is an activity/task)
– Purchase paint tools (this is an activity/task)
– Paint north side walls (this is an activity/task)
– Paint east side walls (this is an activity/task)
A WBS is not a schedule, and I am sorry if I disappoint some of you with this statement. Schedules are activity based and indicate what to do, when to do it and the order in which they must be done. This information is derived from the WBS. If you focus on the schedule while developing a WBS you will not develop a good WBS.
Once the WBS is built you may use a scheduling tool to produce the schedule. It will automate most manual scheduling tasks such as moving dates up or down based on effort, duration, dependency to other tasks, resources used, etc.
I believe that we have broken apart the work breakdown structure. Don’t you think so…? Well, I do.
