WBS - An Overview

The work breakdown structure (WBS) decomposes the scope of a large and complex project into simply manageable chunks of work. Each work chunk is a small deliverable. The breakdown follows a hierarchical structure with the final deliverable at the top and works backward to identify the activities and tasks executed in an order, to realize the deliverables. 

WBS enables efficient management, tracking, and on-time completion of the project. Project managers use WBS for their work planning, scheduling, and organized execution of their projects.

Levels of a WBS

The WBS follows a hierarchical structure decomposing the final deliverable into its principal components, further divided at successive levels to have activities and executable tasks. The items at the lowest level are comprehensible as individual tasks to people who work on them. 

The layers of the WBS are selected to simplify the planning, scheduling, execution, and monitoring of the project from the concept stage to completion. There are four main types:

• The top-level/root - The project itself or the final deliverable.
• The phases/deliverables - Different phases in the project development and the deliverables produced at different phases.
• Work packages - Breakdown of the deliverables into work packages. Each work package is a group of related tasks to achieve the chunk of work. 
• Activities and tasks - Breakdown of the work packages into individual tasks and activities.

Forms of WBS

WBS is very flexible and can take many forms:

• Outline view - List view of the phases, deliverables, work packages, and activities/tasks/subtasks. Items in the successive levels are numbered in a multi-level numbering system.
• Tree view - The multi-level organization view shows the phases, deliverables, work packages, and activities/tasks.
• Gantt chart - The phases and tasks are shown in a Gantt chart:  

Components of a WBS:

• WBS code and task name - Each task is identified by a WBS code number. The tasks are serially numbered in a multi-level numbering system, so the tasks in the next level of the hierarchy have sub-numbers of the serial number of their parent in the previous level. The task name shortly describes the task and/or activity.
• Task owner - The subcontractor, architect, engineering, or consultant company to whom the task is assigned. This entity is responsible for moving the task from assignment to completion and marking the progress.  
• Task dependency - Some of the tasks follow other tasks and may have to wait until the parent task is commenced or completed before they can start.  
• Start, finish dates, and estimated time to complete - The prospective start and completion dates of the task and the man-hours required to accomplish the task within the planned end date.   
• Task status- The progress report of the task.

WBS for project schedule

A WBS should derive mutually exclusive tasks and comprehensively cover the full scope of the project without any omissions. It contains all activities and tasks and their order of execution to complete the project successfully. This gives clear visibility on phases, critical tasks, and subtasks and their dependencies and lets you plan on resource allocations and collaborations.  

Linarc lets you easily specify the phases, deliverables, work packages, and activities/tasks in order, their dependencies, time and cost estimates, start/end times, assigned contractors, and more from a well-structured WBS. The details are also represented as a Gantt chart, which simplifies planning, monitoring, and tracking the progress of the project.   

How to create a WBS

The following are high-level descriptions of the steps involved in creating a WBS. Each step must be drilled down to granular levels to split a huge project into simple, manageable work chunks.

• Step 1—Goals and objectives. Determine the scope, objectives, and who will participate in the project.
• Step 2 - Identify project phases - Divide the project statement of intent into a series of phases from conception to completion.
• Step 3—Identify deliverables—Create a list of deliverables for each phase and identify the subcomponents required for creating each deliverable. Examples include sub-deliverables, work packages, resources, participants, etc.
• Step 4 - Divide each deliverable into tasks and subtasks required to deliver it. List down those tasks and subtasks in the proper order in which they are to be executed. Specify dependencies between tasks
• Step 5 - Assign the tasks to respective teams. 

Linarc's master schedule tool simplifies creating a WBS and importing it into the project schedule. You can add milestones, checkpoints, etc., to your schedule to get a better breakup and vision of the progress. The scheduler also allows project managers to mark the progress of each task. The statuses of the tasks are dynamically updated in the Gantt charts and dashboard charts.