Work breakdown structure – part 3
Number of levels
How far do you go in identifying the list of components in the work breakdown structure?
Once you get to the stage where you can allocate tasks to individuals or groups you can stop.
Even this level may be too far in terms of overall control.
Ideally, you will need to go far enough to afford accurate costs and time frames.
As you go deeper and deeper into a project the number of items in the work breakdown structure rises rapidly.
It may be OK to take the detail to a particular level that can then be ‘managed’ locally at the lower levels.
It will then be up to the local managers to identify all of their requirements to meet a particular objective that consists of many tasks.
They can do this by producing their own schedule or the project manager (as is usual) would incorporate the tasks and provide a copy for comment.
For large projects there may be Project Support who can do this.
When working using project management software it is fairly straight forward to show / hide any task that you do not want to view by ‘rolling’ up tasks into a higher level.
You should find that going down to about 5 levels is often adequate.
Also, bare in mind that the level of detail that you may need at the start of the project won’t be as high.
Initial work is carried out to look at costs, commitments and overall feasibility.
Hence, the initial work breakdown structure and subsequent schedule will be smaller with less detail.
When a plan (schedule) is put together for the submission of an estimate it is likely to be top level and not go too deeply.
In this case, the potential error in the estimation will be higher.
If the project is less complex, and thus easier, it will be possible to go to deeper levels and create a more accurate estimate.
In general, for a large project, the number of levels can reflect the number of personnel in the organisation at that level.
For, example, the very top level is run by the Chief Executive Officer who is one person.
The next may be run by Departmental managers, who may number, for example, 4.
The next level by Project Managers, who may number 3 for each department say a total of 12.
The next level may be supervisors or lower managers. There may be say, 4 for each Project Manager giving a total of 48.
Beneath these there may be 5 people for each lower level manager or supervisor, giving a total of 240 people.
Hence, the overall number of personnel in this company might be 1 + 4 + 12 + 48 + 240 = 305.
All, in effect, working on one project.
With this sort of structure accountability flows from the top to bottom with reporting flowing from bottom to top.
The use of sub projects
If you need to go to lower levels than 5 you may need to divide the major project into subprojects.
This will make the schedule easier to grasp visually and should make it easier to manage.
Some aspects of any plan will require expert skills that either you don’t posses or you don’t wish to retain on a permanent basis. In this case you will sub-contract the work to third party specialists. You will have little control over the output of these workers and it may be best treated as a sub project.
The scope may be flawed
If you find that you are heading towards level 10 it is possible that the scope of the project may be flawed and should be reviewed.
Key milestones and review points
The key milestones and any review points will be seen at the higher levels.
Management or administration
Managerial tasks are often forgotten in the schedule and should be included.
Whilst these should have little impact on the end date they will add to the cost.
horizon planning
Clearly, it can be difficult to predict what will happen 1 week from today let alone 6 months or 1 year.
Therefore, the detail in the plan should reflect the timescale involved.
The early stages of a schedule, given the go ahead, should be planned in greater detail than the latter stages.
It is only when the project approaches a milestone that the Project Manager should trigger detailed planning of the subsequent stages.
This approach is often known as ‘horizon planning’.
These are also discussed as part of 'The Complete Risk Management package'.
Budget and cash flow
The final schedule derived from the work breakdown structure has to be approved at an appropriate level before any work starts.
The schedule will contain all of the tasks, identified dependencies, timelines and durations to the best estimate of the project team.
It should also contain resources, costs and responsibilities.
It is very important that this is as accurate as possible as the schedule is a commitment of resource to the project.
Resource means expenditure and that means cash flow. The project will indicate how much cash is required and when.