How to use a work breakdown structure for everyday projects

If you've ever worked on a large project at work, you may have seen a work breakdown structure: a diagram of boxes branching down from the project name into smaller and smaller pieces. Project managers have used them for decades to plan construction, software and defence projects.

The idea is too useful to leave to project managers. A WBS is just a disciplined way of breaking a big thing into small things, and a couple of its rules fix the most common mistakes people make when planning personal projects.

What a WBS is

A work breakdown structure is a hierarchy. At the top is the whole project, described as an outcome. Below it are the major pieces of work. Each of those is broken into smaller pieces, and so on, until the pieces at the bottom are small enough to estimate, assign and do.

The bottom-level pieces are traditionally called work packages. In a personal to-do list, they're your actual tasks.

A WBS says what the work is. It doesn't say when or in what order. Scheduling is a separate step, which is part of why WBS planning feels less overwhelming than drawing up a timeline.

Two rules worth borrowing

The 100% rule

Each level of the breakdown must account for 100% of the work in the level above, and nothing more. If you complete every child of a task, the task is complete. If something's left over, a child is missing.

This rule catches the gaps that sink personal projects. Planning a wedding, you list venue, food, music and outfits, and only find out a month before that nobody's done invitations. Checking each level against the 100% rule ("if I do all of these, is the parent done?") surfaces the missing piece early.

It also stops scope creep. If a child doesn't contribute to its parent, it doesn't belong there. Move it to its own project or drop it.

Break down by things, not activities

Project managers prefer to break work down by deliverables (things that will exist) rather than activities (things you'll do), at least at the upper levels.

Compare these for a home office:

By activity:

• Research
• Buy things
• Install things
• Tidy up

By deliverable:

• Desk area
• Lighting
• Storage
• Cable management

The deliverable version is easier to check against the 100% rule and easier to track. You can see that "lighting" is done; "research" is never really done. At the lowest level, tasks naturally become activities ("measure the alcove", "order the lamp"), and that's fine.

How small should the pieces be?

Formal project management often uses the 8/80 rule: work packages should take between 8 and 80 hours. That's for teams on large projects where tracking hundreds of tiny tasks would be overhead.

For personal projects, go much smaller. A good bottom-level task:

• starts with a verb
• has a clear end point
• fits in one sitting, ideally under an hour

The reason is different from the corporate one. At work, the aim is estimation and assignment. At home, it's getting started. A task you can finish in one evening is a task you'll actually start on a Tuesday night. I covered that side of it in how to break down a big project.

Worked example: a home office

Outcome: A home office I can work in all day by the end of next month

• Desk area
  • Choose a desk that fits the alcove
    • Measure the alcove
    • Shortlist three desks under £300
  • Order the desk
  • Assemble the desk
• Chair
  • Try two chairs in a shop
  • Order the chair
• Lighting
  • Order a desk lamp
  • Swap the ceiling bulb for a daylight bulb
• Storage
  • Clear the shelf above the radiator
  • Order two magazine files
• Cable management
  • Order a cable tray
  • Fit the cable tray under the desk

Check the 100% rule at the top level: if the desk area, chair, lighting, storage and cables are all done, is the office ready to work in all day? Probably, but there's no mention of internet. Add "Network": "Test wifi speed at the desk" and, if it's poor, "Order a powerline adapter". The rule caught a gap before it became a problem.

From WBS to a to-do list

On paper, a WBS is a box diagram. As a to-do list, it's a tree: every box is a task, and its children are subtasks. Any list that allows nesting works.

Once it's a tree, the scheduling questions get easier:

• What's next? Pick the next unfinished task on the branch you're working on.
• What's today? Choose a few bottom-level tasks and put them on today's list. In Tatask you'd star them so they appear in Today.
• What has a deadline? Put due dates on the tasks that have them, at whatever level they belong.
• How far along am I? Count finished children. Tatask shows this as a ring on each parent task, so you can see that "Desk area" is two-thirds done without opening it.

From breakdown to schedule

Once the tree exists, you can turn it into a rough plan in three steps.

1. Mark dependencies. Some tasks can't start until others finish. You can't assemble a desk you haven't ordered. Note these, either by putting dependent tasks in order within a branch or with a #waiting tag.
2. Date the fixed points. Anything with a real deadline (a delivery slot, a booking) gets a due date. Leave everything else undated.
3. Choose this week's tasks. From the branches that can move, pick the next few tasks for this week. Don't schedule the whole project. Schedules for personal projects go stale within days; a fresh weekly choice doesn't.

This keeps the WBS useful as the project changes. When a new task appears, it goes into the tree where it belongs. When plans change, you choose differently next week. The tree stays the source of truth for what the work is, and your weekly and daily lists decide when.

When to use a formal WBS

For most personal projects, a quick breakdown is enough. The WBS rules earn their keep when:

• the project is big enough that missing a piece would hurt (a house move, a wedding, a product launch)
• other people are involved and need to see the whole shape of the work
• you keep finding surprise tasks late in the project

In those cases, spend twenty minutes building the tree properly, checking each level against the 100% rule. Then stop planning and start on the first task.

Further reading

• How to break down a big project, my main guide to breakdowns
• Task management for the digital age, on why hierarchical lists suit modern work
• Breaking down complex projects, with strategies for larger work projects
• The nested tasks feature page, for how this works in Tatask

#projects#breakingdowntasks#planning#taskhierarchy