Key takeaways

  • A work breakdown structure (WBS) breaks down a project into smaller, task-oriented components.
  • There are two primary types of WBS: deliverable-based and phase-based.
  • The WBS is essential for cost estimation, schedule development, and control within a project.

What is a work breakdown structure?

In project management, a work breakdown structure represents a structured division of a project into smaller, deliverable-focused elements. It segments the team’s tasks into more digestible portions.

Infographic depicting an example of a project's work breakdown structure in a tree format.
Source: TechnologyAdvice

As outlined in the Project Management Body of Knowledge, the WBS acts as a “tiered dissection of the complete scope of work that the project group needs to execute to meet the project goals and generate the required deliverables.”

WBS stands as a cornerstone in project management, particularly in the project planning phase. It lays the groundwork for precise cost predictions and oversight, steering the creation and monitoring of schedules. 

Instead of focusing on the tasks required to produce the project’s primary outcomes, the WBS narrows the focus to each task’s individual outcome. This setup makes linking conditions at different stages easier, like connecting what’s functionally required to the actual design plans.

What are the components of a work breakdown structure?

A work breakdown structure comprises six components: deliverables, tasks, subtasks, work packages, milestones, and control accounts.

Deliverables serve as the end goal of a project and often define what success looks like. They can be tangible, like a physical product, or intangible, like a service or a piece of knowledge.

For instance, deliverables in a software development project might include the software application, user manuals, and training materials. In a construction project, the completed building or infrastructure would be the deliverable.

Tasks refer to the specific activities or steps that are required to produce a deliverable.

In the context of a software development deliverable, tasks encompass activities like gathering requirements and developing, testing, and deploying code. By breaking down the work into these actionable steps, it becomes easier for team members to understand their responsibilities and managers to monitor progress.

Subtasks are granular activities that fall under a broader task. They provide a more detailed set of instructions or steps to complete a single task.

For example, a software project’s coding task might include subtasks like writing an authentication module or developing a user interface for the login page. These subtasks ensure that every aspect of a task is clearly defined to minimize the risk of overlooking crucial steps.

Work packages are the smallest units in a WBS. They represent a collection of tasks or subtasks that can either be assigned to a specific team or outsourced.

In a construction project, a work package might be installing the electrical wiring for the first floor. These packages are what allocate resources, assign responsibilities, and estimate costs and durations. They can also define contracts for outsourced work.

A milestone is an event or marker that signals when a significant task or phase is complete. In the journey of a product launch, milestones might be events like completing the prototype, conducting the first successful test, and launching the final product.

Milestones are instrumental in tracking a project’s progress and ensuring it remains on schedule. They also offer opportunities for periodic project reviews and evaluations.

A control account is a specific point in the WBS for assessing the project’s performance. At these junctures, the planned work, budgeted cost, and scheduled time are evaluated against the actual performance.

For instance, after hitting a milestone, a control account assesses whether the project is still on time, under budget, and within scope. These accounts are essential for effective project management as they help correct for deviations from the original project plan.

Pro tip: It’s essential to balance the level of detail in the WBS. While it’s crucial to be thorough, too much detail can become challenging to manage.

What are the different types of work breakdown structures?

Depending on the nature of your project, it might be more effective to structure your WBS around deliverables (e.g., URL, layout, content) or phases (e.g., discovery, design, launch).

Deliverable-based

A deliverable-based WBS is a systematic approach to project management that organizes and defines the total scope of a project based on its outputs or results.

The core principle of this structure is its emphasis on segmenting a project according to its tangible or intangible end products, known as deliverables. Each section or tier of the WBS directly corresponds to a specific output that the project aims to produce.

Such a method is especially relevant to projects that have clearly defined deliverables from the beginning. Examples include manufacturing firms producing a designated product, software companies developing an app, and research entities targeting a particular study outcome.

Phase-based

The phase-based WBS categorizes a project based on sequential stages of progress.

Each stage represents a significant milestone in the project, and the tasks within that stage are geared toward achieving a specific objective. This approach benefits projects that naturally evolve through clear, sequential stages.

For instance, construction companies, where projects transition from design to foundation work to construction to finishing, would find the phase-based WBS more valuable than the deliverable-based orientation. Similarly, film projects benefit from having clear phases before, during, and after the cameras roll.

Also read: What is Agile Project Management (APM)?

Types of WBS charts and tools you can use

At its essence, this is a structured list that delineates tasks and subtasks. Consider it an enhanced version of the conventional to-do list that serves as the bedrock of any project.

Trello’s card-based system is perfect for creating WBS lists. You can create detailed tasks, assign them to team members, and monitor their progress. The software is like a digital whiteboard where you can move tasks around as needed.

Spreadsheets offer the unique advantage of formulas and conditional formatting to make managing tasks and dependencies more efficient and effective. For example, you can leverage a WBS spreadsheet to forecast the impact of budget or deadline changes.

Smartsheet offers the familiarity of traditional spreadsheets while adding essential project management capabilities. The grid view behaves similarly to Google Sheets or Microsoft Excel, allowing you to organize and filter tasks based on precise details and conditions.

Smartsheet displays a grid view of a project's task breakdown.
Smartsheet supercharges traditional spreadsheet capabilities to simplify task management. Source: Smartsheet
Visit Smartsheet

A WBS tree diagram is a visual breakdown of task heirarchies:

  • The trunk is your primary goal.
  • Branches that sprout from the trunk are your major tasks.
  • Smaller branches are your subtasks.

Lucidchart is a gem for creating tree diagrams. With its drag-and-drop interface, you can easily map out tasks and see the bigger picture. It’s like having a bird’s eye view of your entire project. Lucidchart makes preparing a tree diagram more efficient.

Visit Lucidchart

Gantt charts are indispensable tools for visually representing task timelines and their interdependencies. Envision a horizontal bar graph where each task is denoted by its own bar, signifying its duration. The length of the bar correlates with the duration of the task. Overlapping tasks? This indicates the presence of dependencies.

Wrike is tailor-made for Gantt charts. It allows you to set task durations, dependencies, and even milestones. With Wrike, you can see how your project timeline unfolds, making adjustments as needed. It’s like having a crystal ball for your project’s timeline.

Visit Wrike

Guidelines for creating a successful work breakdown structure

Here’s a step-by-step guide to creating an effective work breakdown structure:

1. Define the project

Begin by clearly establishing the project. This might be straightforward for some projects, but for others, it might require refining the actual scope to ensure the WBS is appropriately scaled and manageable.

Use Asana to create a new project board where you can outline the project’s main objectives and goals. Asana’s custom fields allow you to add additional information, such as project stakeholders, budget, and expected timelines.

Visit Asana

2. Set project boundaries

After defining the project, set clear boundaries on what is and isn’t included in the WBS. This ensures that the scope remains focused and avoids potential scope creep.

ClickUp’s Spaces feature allows you to set clear boundaries for your project. Creating a dedicated space for your project ensures that all tasks and discussions remain within the defined scope.

Visit ClickUp

3. Identify project deliverables

List out the high-level deliverables associated with the project. This could be items like a Project Scope Statement or a Mission Statement. Wrike’s folder structure is perfect for listing high-level deliverables. Create a new folder for each deliverable, which can be broken down into tasks and subtasks as you progress.

4. Define Level 1 elements

Using the 100% rule, create the Level 1 deliverables. This level typically represents the entire project. For instance, if you’re working on a new website, Level 1 might be “Website for New Brand.”

Use monday.com’s board view to create columns for each Level 1 deliverable. This visual representation helps us understand the project’s primary components at a glance.

5. Decompose Level 1 elements

Break down each of the Level 1 elements into smaller components. This process, known as decomposition, involves dividing tasks into smaller pieces, ensuring the 100% rule is applied at each level. Continue this breakdown until no further decomposition would benefit project management.

Trello’s card system is excellent for decomposition. For each Level 1 element, create cards for its sub-elements. You can further break these down using checklists within each card.

Visit Trello

6. Assign team members

Identify an individual or team responsible for each element or task in the WBS. This ensures accountability and clarity in roles and responsibilities. ClickUp’s assignment feature ensures that each task or subtask has an accountable individual or team.

Visit ClickUp

7. Create a Gantt chart

Create a Gantt chart to complement the WBS. A Gantt chart visually represents activities over time, allowing you to see the project schedule and the timeline of various activities. monday.com’s Gantt chart view provides a visual timeline for your project, perfect for tracking progress and dependencies and ensuring the project remains on schedule.

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Irene Casucian Avatar
Irene Casucian
Staff Writer
Irene Casucian is a staff writer for TechnologyAdvice. She spends her days researching and exploring different types of software, topics and trends within the industry.