Work Breakdown Structure

The work breakdown structure (WBS) is a hierarchical breakdown of the complete project scope. It presents all of the work that will be carried out by the project team during the life of the project, including the project management work.

As a hierarchical decomposition of the project work, each descending level of the WBS is increasingly detailed. Let’s consider a construction project as an example.

The highest level of the WBS would include the project name. Beneath that, we might find levels like: footer, framing, plumbing, electric, roof and so forth.

In this example, the second level displays the project deliverables. Note; however, that there’s more than one way to decompose a project. It could also have displayed the project life cycles on the second level and placed the deliverables on third level.

Regardless, we continue with the decomposition. Beneath footer, we might find: survey, excavation, gravel, set frames, set rebar, inspection, and pour concrete.

This top-down approach to decomposition continues to a point where the WBS components represent a work package. It’s the place where cost and duration can be estimated and where products, services or results can be verified.

A work breakdown structure can be constructed in several formats. Among them, it can appear in the form of a flow chart, an outline or a quasi-list. With each of these formats, form follows function. The template below uses an outline or list type of presentation.

The work breakdown structure is created by the project manager with considerable input from the project team members. It’s crucial that the project manager seek input from subject matter experts and those performing the work.

Even with input from everyone, full decomposition might not be possible until future work is known or completely understood. As such, the WBS may be revised several times during the life of the project.

To construct the work breakdown structure, we must know all of the deliverables, requirements and the work activities; therefore, inputs include the scope management plan, the project scope statement, requirements documentation, enterprise environmental factors and organizational process assets.

The work breakdown structure is an important project management tool. For starters, it helps organize the project. Once constructed, it’s used for calculating costs and estimating the project schedule. When the project is underway, it’s used for making comparisons. Because the WBS is a part of the scope baseline, it’s also relied upon for controlling project scope.

It becomes finalized by assigning a control account (a management control point) to each work package and by establishing a unique identifier for that work package from a code of accounts. Each control account may include one or more work packages, but each of the work pages should be associated with only one control account.

Help yourself to this free WBS template. It’s easy to modify and there’s no login required.