Project managers optimize work by adapting best practices, secrets, techniques, and tricks. They use their skills, experiences, intuition, and tools to manage a project effectively and efficiently. There are several project management methodologies and one of them is the critical path method.
Let’s dig in to find out more about this technique.
What Is the Critical Path?
A critical path maps a sequence of tasks that must be completed to finish a project. The tasks on a critical path are called critical activities and a delay in any one of them leads to an overall delay in the project completion. Because critical activities cannot be missed, you use the critical path to determine the total duration of the project.
The critical path method is essential to managing a project well.
Let’s find out how it helps in project management.
Critical Path Method in Project Management
The critical path method (CPM) is also known as the critical path analysis. It is a scheduling procedure and incorporates a network diagram to represent a project and the sequence of tasks which are known as paths. Once all the paths have been identified, the duration of each path is determined using a critical path algorithm.
This helps managers outline the timeline of the project on a Gantt Chart. To sum it all up, the critical path includes the following:
- Identifying critical activities in a project and the dependencies between them
- Estimating the duration of each task
- Determining the critical path considering the critical activities and dependencies
- Focusing on planning and controlling the critical activities
- Creating project milestones and deliverables
- Setting deadlines and stakeholder expectations
After taking into consideration all of the above points, you know which tasks are critical and must be prioritized. As a result, you can allocate resources to these tasks accordingly. You also get to identify tasks that are not as important as others so you can put them at the backend to focus on later.
Benefits of Critical Path
Now that you know what is a critical path, let’s go a little deeper and familiarize ourselves with its benefits. This will give you all the reasons to implement this method in your next project.
Identifies High Priority Tasks
The critical path method defines tasks that are of the highest importance to a project. It allows you to plan your schedule well in advance so that there are no delays in project completion.
Another benefit of this method is that it helps reduces timelines. A CPM displays critical activities, their durations, and sequence. This gives you a better understanding of how you can modify the timelines for each task, to ensure that the project is finished on time.
Compares Planned With Real Status
You can easily compare planned progress with the actual one. With the original baseline insight, you can analyze how far you have come in terms of tasks that are completed. You can predict the time duration for in-progress activities and look for any changes that need to be implemented for upcoming tasks. When you update the rules, you can have a visual representation of the planned vs actual progress.
Represents the Project Visually
This method helps project managers outline a project’s timeline on a Gantt chart. With the visuals in front, you can navigate through the process easily, see tasks that are completed, those that are in progress, and estimate the time for project completion. Also, you’ll know where to allocate the most resources and how can you improve time and resource management for future projects.
Another great benefit of using this project management technique is that you get to see which tasks are dependent on each other. With that in front of you, you know which tasks have to be completed in a given time frame so that the next task can be started immediately. You learn how to prioritize tasks and make necessary modifications on the fly.
The critical path method gives you the flexibility to either shorten the project or compress a few tasks to meet the deadline. There are two ways to achieve this:
Fast-tracking reduces the time frame of the project. In this, you analyze only the activities on the critical path and decide which of them can be performed in parallel. However, while doing so, you also run the risk of performing critical activities in parallel which were initially supposed to be performed in a sequence.
This refers to the short duration of time for which you can schedule an activity. This happens when you allocate more resources to that particular activity. However, crashing certain tasks compromises cost-effectiveness, and maybe even quality, as the focus shifts to speed.
When running a certain project, you might face the issue of resource constraints. If you plan or running certain activities parallel to each other, you might require additional resources such as people to work on both tasks. As a result, you may have to reschedule those activities. However, you can solve this conflict via resource-leveling.
Resource leveling helps resolve issues related to resource allocation. A resource-leveled schedule may include delays due to the unavailability of resources.
Resource leveling may result in a path that can turn a path that was previously a short one into the longer one. It is also known as the most resource-critical path.
Limitations of Critical Path
One limitation of this method is that it only works well with everyday, complex projects. It only allows for minimal changes in time and is not adaptable to chaotic projects.
Example of a Critical Path Method
The critical path method is used for simple as well as complex projects. But for the sake of your understanding, let’s apply this method to an HR project.
The aim of the project is to hire 2-3 employees for a marketing managers position. How will you go about it? You will start off with the following:
- As an Hr manager, you need to understand the requirements of the role first
- Post a job opening on your selected platform
- Screen the applications
- Shortlist potential candidates
- Hold first round of interviews
- Schedule a group discussion
- Arrange a final round with the marketing head
- Send out an offer letter
- Prepare the employment contract
- Conduct an onboarding session
Now, you know some stages of this project are dependent on each other. For example, from stage 3 onwards, activities are sequential and dependant. So you know that these all stages from 3-10 are critical activities. They will be placed on the critical path of the project as completion of one relies on another.
Furthermore, your next step will be to determine the duration for each stage and the overall project.
How to Make a Critical Path Diagram
A visual representation of the diagram can be done on paper and on excel using a Gantt chart. You may use graphs, arrows, sections, and columns to represent the diagram fully.
There are also many software and tools that you can use to identify a critical path. It is more convenient with just a click of a button rather than resorting to the conventional way of sketching on a piece of paper.
6 Key Stages of Critical Path Method
When you start a project, you need to break down the work structure into tasks or activities. This includes only the most important or high-priority tasks. If you mention even the smallest of tasks, the project may become too chaotic to be mapped out on a critical path.
A work breakdown structure divides the project into manageable sections. You begin with identifying the major deliverables of the project and then move onto defining the critical tasks. You can represent a work breakdown structure in the form of a list, tree diagram, or table.
Here is one example for you.
Establish Activity Sequences
There will always be some tasks in a project that will depend on the completion of a few others. It is better to list down the predecessors of each activity as it will bring more clarity. For even better results, ask yourself the following questions:
- Which task precedes which?
- How many and which take should end at the same time?
- What tasks will follow this task?
Create a Network Diagram
A network diagram visually represents the tasks in order and their dependencies. So once you know all the tasks and their dependencies, you can represent them in the form of a critical path analysis chart also known as the network diagram.
You can draw this diagram either on a piece of paper or use software programs.
Determine Time Duration for Each Activity
The next step is to estimate the time interval for each activity. You can either seek help from the experts or use your intuition. If you’re managing a small project, then the estimate is more likely to be in days. However, if it’s a big, complex project, then it may take up to several weeks to finish it off.
Spot the Critical Path
You can identify the critical path in two ways:
Eyeball the Network
Scan your network diagram and look for the longer path that has the longest sequence of activities. the longest path here signifies the longest duration and not be with the most and of boxes or nodes.
Forward Pass/Backward Pass Technique
Using this technique, you can determine the earliest start and finish time and the latest start and finish times.
Update the Network Diagram
As the project progresses, several modifications may take place. Activities may start or end at different times than what was initially predicted. Whatever the changes, don’t forget to add the new information into the diagram. Sometimes, the critical path may also change. It will also give you a bird’s eye view of the project as a result of which you will be able to identify the dos and don’ts for the next time.
Key Definitions of Critical Path Method
We have gathered some keywords that are frequently used when implementing the CPM. Let’s have a look:
Earliest Start Time
This is the earliest time that you can start a task. However, you will have to identify if there are any preceding tasks or constraints that can impact it.
Latest Start Time
This depicts the maximum time by which you can delay starting a certain task. As a project manager, you have to be very careful when identifying this as any further delay can hamper the project performance considerably.
Earliest Finish Time
As the name suggests, this is the earliest a task can reach its completion.
Latest Finish Time
The maximum time by which an activity can be finished.
Float is also known as slack. It means how long can a project manager delay a task before it affects the planned schedule and project’s deadline. Usually, the activities on the critical path have a zero float. However, if a certain activity has a float greater than zero, then it can be delayed without having an impact on the project’s timeline.
Critical Path Drag
Project managers use this term when some extra time is added to a project. This determines how long will the project take to end because of certain constraints.
As a project manager, you would want a way to streamline all the tasks in a way that doesn’t hamper performance and quality. You will also want the project to finish on time.
If you haven’t used critical path analysis before, you should really give it a try now. This method will help you differentiate high-priority tasks from low ones. You will be able to allocate your resources towards the former and meet the deadlines without unnecessary changes.
With a visual diagram, this method will also help you complete a project efficiently and effectively. Moreover, it will also become easier for your team to follow.