What is a WBS? Work Breakdown Structure

What is a WBS? Work Breakdown Structure

WBS stands for Work Breakdown Structure. It is the structure that organizes project deliverables into distinct identified elements. According to the PMBOK Guide, Work Breakdown Structure refers to “a hierarchical breakdown of the total scope work that must be completed by the project team in order to achieve the project objectives and create required deliverables”.
The scope baseline of the project contains all the work required to complete the project. It consists of the scope statement and WBS. The work is what creates the WBS. The Project Manager must reference the following:
Project Charter
Contract(s)
Scope Statement(s).
Project Management Practices

The WBS covers all the work required to earn your salary. Scope creep is any work that you are asked to do for free and not included in the WBS. The Scope Statement is the first part of the WBS. It should explain “what is” or “is not” for each work element. A WBS is a short description of the work that uses nouns and not verbs. The WBS Dictionary contains detailed information about each component activity as well as scheduling information.
Another way to look at a WBS, is that it clarifies the work required to communicate project scope. The WBS should have at least two levels. WBS can also be done efficiently when it is time-phased. The WBS structure should reflect the components that are most important to the project. This can be done with a network diagram.
Let’s build a house to illustrate how a WBS works. Let’s say that you were given the scope to build a house.
Primary Structure
Electrical
Plumbing
Inside Walls

This would be the order of construction based on a network diagram. The structure of the house must be completed before electrical and plumbing can be started. After that, the inside wall finish can begin. These deliverables will only need more structure and definition. The “Primary Structure” could be used to handle many things. Therefore, it should have a couple of additional levels that describe the elements it consists of. This could include:
Primary Structure
Foundation

Topography
Excavation
Cement Pour
Exterior Walls
Roof

This is likely the order they are completed. After the walls have been erected, Exterior Walls are completed. The House Build WBS could look like this:
House Building
1. Primary Structure
A) Foundation
Topography
Excavation
Cement Pour

b) Exterior Walls
c) Roof
2. Electrical
3. Plumbing
4. Inside Walls
These components are not activities that need to be done. The WBS Dictionary contains information about the activities and resources needed to achieve your goals.
These WBS components should eventually be combined with an OBS structure in order to create control accounts. An Organizational Breakdown Structure (OBS) is a way to highlight staffing levels. A control account is a charge ID that an individual would use to identify the work they are supposed to do.
This WBS allows for easy change control, program scheduling, and documentation for horizontal and vertical traceability. Vertical traceability refers to the interdependence of project documents such as the SOW (Integrated Master Schedule) and the IMS. Horizontal traceability refers to the relationship logic between the components and how they are scheduled.
Author – Gregory Morrow