How to build a WBS
Whether the WBS should be activity-oriented or deliverable-oriented is a subject of much discussion. There are also various approaches to building the WBS for a project (see e.g. How to Build a Work Breakdown Structure below). Project management software, when used properly, can be very helpful in developing a WBS, although in early stages of WBS development, plain sticky notes are the best tool (especially in teams).
An example of a work breakdown for painting a room (activity-oriented) is:
- Prepare materials
- Buy paint
- Buy a ladder
- Buy brushes/rollers
- Buy wallpaper remover
- Prepare room
- Remove old wallpaper
- Remove detachable decorations
- Cover floor with old newspapers
- Cover electrical outlets/switches with tape
- Cover furniture with sheets
- Paint the room
- Clean up the room
- Dispose or store left over paint
- Clean brushes/rollers
- Dispose of old newspapers
- Remove covers
The size of the WBS should generally not exceed 100-200 terminal elements (if more terminal elements seem to be required, use subprojects). The WBS should be up to 3-4 levels deep. Each level should be 5-9 elements broad. These suggestions derive from the following facts:
- short-term memory capacity is limited to 5-9 items.
- having fixed time to plan a project, the more terminal elements you have, the less time there is to pay attention to any single one of them. Consequently, your estimates are less thought-through.
- the more terminal elements you have the more there are potential dependencies among them (see fact 2 above for consequences).