Comment décidez-vous du niveau de détail et de granularité de votre structure de répartition du travail?

The WBS should reflect the work, and how it is done. Whether that is building an office tower, designing a software application, or sending a rocket to the moon. Start with the top level deliverables and break them down into the progressively more detailed "jobs to be done" to roll up to those deliverables. MIL-STD-881 is used by the US government as a guide to different types of projects, but there are as many ways to build one as there are project managers! The WBS should be clear enough that everyone can see the work to be done, and granular enough that each line of the WBS is the clear responsibility of one person/Cost Account Manager (CAM).

This answer would depend on the application. For example if this is proposal schedule it may be at a higher level than that of the actual project. It may more of a summary level of the tasks. However for a real fully executable project the wbs should be broken down to the lowest level of work. What is it that you are actually doing or what task are you performing ?

Determine what the WBS is intended to achieve. Is it for project planning, cost estimation, resource allocation, scheduling, or risk management? The purpose will influence the level of detail required. Also, Stakeholders such as project managers, team members, and clients might require different levels of detail. Ensure the WBS is detailed enough to meet the needs of all intended users.

The WBS should align with your project's purpose, audience, and specific needs. Before crafting it, clarify objectives, user roles, and update processes to decide its depth, format, and structure effectively.

Forget the rules. I think you should create a labor plan based on typical tasks, which are the money makers. Labor plans are normally charted with 3 columns: labor code, description of work, & planned hrs. Add 2 more columns: planned units & UOM. For example: a 50 story tower has water ring mains on each flr. The work consists of inserts, hangers, ring mains, branch piping and terminal connections. Each task happens sequentially as the tower goes up. Each task requires a specific set of tools. And each task is assigned to a select crew. So, the same crew performs the same task with the same tools as the tower goes up. The plan likewise has 5 labor codes, one for each typ task. Each task has 50 planned units & UOM = Flr.

- The 100% rule is important because it ensures that your WBS comprehensively covers the entire scope of the project. Without this rule, there's a risk of missing critical elements, leading to scope creep and project challenges. While the 8/80 rule is essential for task manageability and realism. It prevents tasks from being overly granular, which can lead to excessive administrative overhead, or too large, which can make tracking and management difficult.

The WBS is the fundamental tool by which the program/project manager controls and monitors the project. ALL the work in the WBS is to be done and charged to the project, and ONLY the work in the WBS is to be done and charged to the project. 8/80 may apply - but it might not. If the people doing the work can't easily track it to that detailed a level, then they won't. It would be better to have a longer WBS element that has real data against it than one that isn't maintained. So long as each WBS element represents one definable task, under the control of one CAM, it can be a thousand hours. You can track progress using Earned Value.

Yes, it’s important to track the work. But why? From the previous example, let’s track one of our 5 typical tasks. The crew installing hanger inserts just completed the 25th flr on our 50-story tower. And they spent 500 hours of their 1000 planned hours. So they're 50% complete and they used 50% of the hours. Measured separately, % complete and actual hrs don't really mean much. But together, you have productivity. If the crew is halfway up the building and they used half the planned hours, their productivity is 100%. A WBS—patterned on typical tasks—makes tracking productivity easy. Why bother? So you can help the crew improve.

When planning, start at the end and work backwards. Delivering a cake? What does that entail? The decorated cake, the box, and the delivery. What goes into the cake? You need buy the ingredients (procurement). How do you know what to buy? You need to confirm the recipe (design phase). How do you make it? Mix, bake, decorate (production). What box do you need (packaging)? How is it delivered (shipping). Just keep asking questions until all the steps are identified. Voila, a WBS! If there is more than one end deliverable, then each leg of the WBS needs to align to one (and only one!) of those deliverables (although some tasks, like management, can be spread across all deliverables, if they aren't one in their own right).

A work breakdown structure is a tool that helps you organize your project by hierarchy. With a WBS, you break down deliverables into sub-deliverables to visualize projects and outline key dependencies. Every work breakdown structure is made up of a few parts: A project baseline or scope statement, which includes a project plan, description, and name Project stakeholders, an organized project schedule, Project deliverables and supporting subtasks Project managers use work breakdown structures to help teams to break down complex project scopes, visualize projects and dependency-related deliverables, and give team members a visual project overview as opposed to a list of to-dos.

There should be detailed scheduling within a WBS, you can create detailed schedules that outline every task and sub-task. This level of detail makes it easier to set realistic timelines and deadlines for each phase of the project. A well-built WBS will also help you improve overall operational efficiency. Resource allocation: The WBS helps in identifying the resources needed for each task. This allows for efficient allocation of resources, ensuring that the right people and materials are available when needed. Milestone identification: Breaking down the project into smaller tasks allows for the identification of key milestones. These milestones serve as checkpoints that help track progress and ensure the project stays on course.

A WBS based on typical tasks is easy to update. I worked on a project that started as a 50-story tower, and halfway through the project, the owners decided to make it 51 stories. No joke. The labour plan changed accordingly, not by adding a new labour code, but by updating the planned hours and the planned units for the affected labour codes. From the previous example, if our plan for hanger inserts was 1,000 hours for 50 floors, it became 1,020 hours for 51 floors. Easy peasy.

The WBS is the central source of truth for everyone concerned about the scope of a project. Any changes need to be approved by the project manager, who will incorporate them into the WBS and distribute and explain the changes. These changes need to be well informed, though, by the people who will do the work. Buy-in from the people executing the work is vital. Ideally, each CAM should create, or at least endorse, the task being added and assigned to them.

As our project advances, we frequently encounter new challenges that lead to fluctuations in the project scope. To address these dynamic situations effectively, we must remain adaptable in our approach to the Work Breakdown Structure (WBS). This flexibility allows us to incorporate or exclude WBS elements as necessary, ensuring that our WBS encompasses the entirety of the project's evolving requirements.

This is a big one. It's silly to let yourself or a project get hemmed in by paper when the paper is what needs to change. Keep tabs on what's working and what isn't, and adjust to suit the overall picture.

Is your structure sustainable? Remember, you have to manage to it and maintain it. If the level is too low, it will fall apart over time.

Evaluate the availability of resources, including personnel, equipment, and budget, when detailing your WBS. Ensuring that resources are allocated efficiently can prevent bottlenecks and project delays, leading to more accurate and realistic task estimations and dependencies. Adjust the granularity of your WBS to reflect the resource constraints and capacities.

The WBS should reflect traceability to the funding for the project. Assuming the enterprise uses a charge number system, every Level 4 task should have an accompanying charge number to track costs. Level 3 Activities or Products should have parent charge number classes to capture groups of charge numbers associates with the Level 4 tasks. Workers executing Level 4 tasks need to record labor hours associated with charge numbers on their time cards. Procurement of goods and services should be identified at level four with WBS numbers and charge numbers. This approach will allow the project manager to develop an effective project controls system, either locally on a PC for small efforts, or within the context of enterprise PMO systems.

There’s more than one way to carry a canoe. Hear are 5 types of WBS’s that I’ve come across in my career: 1. Typical Tasks - the best 2. Floor Codes 3. System Codes 4. Maximum Hours 5. Standard Labour Codes - the worst

Remember that EVERYTHING about a project needs to tie back to the WBS. The schedule is the WBS tasks organized on the calendar, with interdependencies and linkages. The budget is the sum of all of the costs defined in the WBS (labour, material, subcontracts, facilities, travel, ...). The labour plan is the totality of the resources assigned to each WBS leg. All of these things needs to be managed as a whole, but ALL changes originate at the WBS.

Every organization and project should strive to find the optimum level of detail necessary to have positive ROI from the establishment and maintenance of the WBS. For a small team with agile methodologies, the WBS is very short range and should be vague in favor of real-time collaboration. It may be a roadmap, backlog, & KANBAN only. For mega-projects with hundreds of contributors and personnel resources, the WBS may be extensive with a team of analysts to manage it; assigning personnel and financial resources to each item, mapping dependencies, communicating status of work in progress, & making real time adjustments. It all must depend on whether the exercise in adding rigor affords a net gain in value returned.