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6 Min. Read

What Is Critical Path Method in Project Management

What Is Critical Path Method in Project Management

Consistently managing successful projects is a real skill.

Being able to identify and prioritize key tasks in a project whilst handling the client’s demands and managing a team can be quite a rollercoaster.

Whilst there are a number of tricks and methods to effectively manage projects, one of the most important ones is the Critical Path Method.

But what exactly is the critical path method in project management? We’ll take a closer look at what a critical path is, the methods definition and provide you with some examples.

Here’s What We’ll Cover:

What Is the Critical Path?

What Is the Critical Path Method?

What Does the Critical Path Method Include?

How Do You Calculate the Critical Path?

Key Takeaways

What Is the Critical Path?

In project management, the critical path is the longest sequence of tasks that have to be completed. This is to successfully complete a project.

The tasks that appear on the critical path are known as critical activities. This is because if these tasks were to be delayed, the whole project will be delayed with them.

By identifying the critical path of a project, you can figure out the time needed to complete the project. You’ll also be able to piece together a clearer picture of the project’s actual timeline.

In order to find the critical path, project managers will tend to use the critical path method, or CPM. This is to figure out the least amount of time necessary to complete the most vital tasks in a project.

What Is the Critical Path Method?

The critical path method, also known as the critical path analysis, is a scheduling procedure. This is done by using a network diagram to portray a project. It lays out the sequences of tasks required to complete the project, otherwise known as paths.

Once the paths are defined, the time each path will take is calculated by an algorithm to identify the critical path. This in turn then defines the entire project duration.

To put this into simpler terms, let’s say that you’re making a ham sandwich. Making the sandwich would look like this:

  1. Lay out two pieces of bread.
  2. Put the ham on one piece of bread.
  3. Put the second piece of bread on top.

At its base definition, that would be a ham sandwich. There are a number of other things you could add to make it a better sandwich. You could add butter, lettuce, mustard etc, but these would be in addition to the core concept. and not a critical task. It is still a ham sandwich without these added ingredients, just not a particularly good one.

On the other hand, if you forgot a piece of bread or didn’t add the ham then you couldn’t call it a ham sandwich. So the three steps laid out above would describe the crucial tasks necessary to make the project a success.

So these three steps would describe the critical path someone would have to take in order to create a ham sandwich.

What Does the Critical Path Method Include?

The CPM is used in project management by a project manager to create schedules. It helps them to create a timeline for the project. Any use of the critical path method include the following:

  1. Identify each individual task that is necessary to complete the project.
  2. Identify all of the dependencies between the various tasks.
  3. Calculate the critical path based on the tasks’ duration and the various dependencies to identify the critical activities.
  4. Start the project planning, the schedule and control the critical activities.
  5. Set various project milestones and deliverables.
  6. Set the project owner’s expectations related to your project and its deadlines.

Once you have made these considerations, you can start to gain insight into which activities must be prioritized.

Then once the critical activities have been identified, you can allocate the resources needed to get these tasks done.

Any task that isn’t on the critical path can be considered a low priority in your project plan. They can be delayed if they’re taking up too much time or manpower within your project team.

How Do You Calculate the Critical Path?

To properly implement the critical path method, you need to first calculate the critical path sequence. This can be done by following these steps:

  1. Collect Activities: Break down the project and collect all of the activities that would lead to the final deliverable.
  2. Identify Dependencies: Figure out which tasks are dependent on other project tasks before they can begin.
  3. Put Together a Network Diagram: A network diagram depicts the order of the activities.
  4. Estimate the Timeline: Figure out how long each activity will take to complete.
  5. Implement the Critical Path Algorithm: The algorithm has two parts, a forward pass and a backward pass:
  6. Forward Pass: Use the network diagram and the duration of each activity to figure out the Earliest Start time and the Earliest Finish time. The earliest start of an activity is equal to the earliest finish of the previous activity. The earliest finish can be worked out through the formula “EF = ES + t” where “t” is the activity duration. Then the earliest finish of the last activity in the sequence is the expected time required to complete the entire project.
  7. Backward Pass: Begin by assigning the last activity’s earliest finish as its latest finish. You then use the formula “LS = LF - t” where “t” is the activity duration. For all of the previous activities, the latest finish is the smallest of the start times for the activity that follows immediately after.
  8. Identify the Float of Each Activity: The float is the amount of time an activity can be delayed without it affecting the project’s completion time. Seeing as the critical path shouldn’t have a float, the float formula can reveal the critical path: “Float = LS - ES”.
  9. Identify the Critical Path: The activities with 0 float will be the critical path.
  10. Revise: Throughout the execution of the critical path method, you should continue to update the network diagram as you go.

By following these steps, you can figure out which project tasks are critical and which project tasks can float. With this information, you can plan the project schedule far more accurately. You will also be closer to guaranteeing that you’ll meet your project deadline.

Key Takeaways

By implementing the critical path method in your more complex projects, you can go some way to ensuring that you meet your deadline. It also helps you to ensure that the bare essentials of the entire project get completed.

Being able to use project management software such as FreshBooks is a further advantage in the race against time.

FreshBooks is built exclusively for small business owners and their teams. Its aim is to boost productivity and create a seamless collaboration for your team and your clients.

Are you looking for more business advice on everything from starting a new business to new business practices?

Then check out the FreshBooks Resource Hub.