| SCHEDULE TYPE | PROS | CONS |
| Line of Balance | – Effective for projects with repetitive tasks – Facilitates resource planning due to task similarities | – Not suitable for non-repetitive tasks – Difficult to see the project’s critical path |
| Quantitative Scheduling | – Visualizes resource quantities over time – Ties task order to expenses | – Less effective for highly repetitive projects – Can be complex for teams unfamiliar with it |
| Program Evaluation and Review Technique (PERT) | – Clearly lays out milestones and deadlines – Encourages collaboration on complex projects | – Not ideal for projects sharing resources – Can become unwieldy with thousands of tasks |
| Resource-Oriented Scheduling | – Prioritizes resource allocation – Ideal for projects with limited, high-demand resources | – Challenging with multiple resources and activities – Can be complex to manage |
| Gantt Charts | – Popular and easy to understand – Facilitates identification of the critical path | – Can become cluttered with large projects – Lacks context for the amount of work and resources needed per task |
| Last Planner System (LPS) | – Increases detail and specificity as the deadline approaches – Promotes strong collaboration and coordination among team members | – Relies heavily on team cohesion – May highlight issues in team collaboration |
| Critical Path Method | – Identifies the most efficient sequence of tasks – Highlights essential tasks for project completion | – May not suffice as the sole scheduling method for complex projects – Can overlook resources for tasks dependent on the critical path |
1. LINE OF BALANCE
The line-of-balance scheduling method breaks your project into repetitive chunks (e.g., building a skyscraper, which happens floor by floor). Each graph represents one of those repetitive tasks, with time spread out on the x-axis and the y-axis displaying the work area (e.g., each building floor).
As workers progress on the task, the chart will reflect how long each iteration takes. Given the repetition, you’ll be able to plan resources effectively, as there will be many similarities.
Goodyear developed the line of balance method in the 1940s, later refined by the U.S. Navy.
What is the line of balance method good for?
Discussing your progress alongside a formal objective plan on projects involving lots of repetition can be tricky. The line of balance method addresses this challenge. It also helps in forecasting your team’s future performance. Both of these advantages are very useful for effective resource and workforce management.
Line of balance disadvantages
The line-of-balance technique suits assembly line-type tasks with several similar phases. Other construction schedule types would make more sense for tasks not involving that sort of repetition.
It’s also difficult to get an overview of the project’s critical path since Line of Balance only displays progress on individual activities.
2. QUANTITATIVE SCHEDULING
Quantitative scheduling is sometimes referred to simply as Q scheduling. It utilizes bar charts to help you visualize resource quantities and the locations and times they’ll be needed. This is the only method for scheduling in construction management that ties the order of tasks to your expenses per resource.
What is quantitative scheduling good for?
Quantitative scheduling is great for projects involving some repetition and variable quantities of resources.
Quantitative scheduling disadvantages
Quantitative scheduling falls short on projects that involve significant repetition. It’s also a fairly new type of construction schedule. If some collaborators on your project aren’t familiar with it, you may have to spend more time explaining things than is justified by its benefits.
3. PROGRAM EVALUATION AND REVIEW TECHNIQUE (PERT)
PERT is not construction-specific but useful in organizations that seek to analyze key events and interdependencies along a project’s ideal path to success. In other words, it lays out the milestones that will indicate progress on a project.
What is PERT good for?
PERT lays your schedule out very neatly and allows for differentiation between fixed deadlines and milestones with which you, as the contractor, have some flexibility. It also keeps fixed deadlines top-of-mind and features a layout simple enough to encourage collaboration across many teams, even in complex projects.
PERT also encourages you to create different timelines for activity completion, including the following:
Optimistic time: This is the best-case scenario.
Pessimistic time: This is the longest foreseeable time it will take you to complete a task.
Most likely time: Assuming no major challenges are present, this is when your activity should be completed.
Expected time: Accounting for problems (which are largely inevitable in construction anyway), this estimates how long it will take you to complete the activity in question.
With these, you can communicate your intentions given a few different circumstances.
PERT disadvantages
If you’re running multiple projects that share resources, a PERT chart won’t accurately convey that. PERT can also complicate projects involving thousands of interdependent tasks, increasing expenses and maintenance efforts.
Your previous expertise will also limit your ability to provide accurate timelines for activity completion. Without access to relevant and useful data, your predictions will likely be way off.
4. RESOURCE-ORIENTED SCHEDULING
As its name would suggest, resource-oriented scheduling puts your available tools at the forefront of planning project completion. The goal is to identify and address situations where multiple parties need access to resources simultaneously.
What is resource-oriented scheduling good for?
As Chris Hendrickson of the Department of Civil and Environmental Engineering at Carnegie Mellon University writes, resource-oriented scheduling is ideal when resources are limited yet essential for a project to be completed properly. This is especially true when those resources are in high demand.
Resource-oriented scheduling disadvantages
This is one of the trickiest types of construction schedules in situations where you have many resources to allocate to several activities throughout your project.
5. GANTT CHARTS
Gantt charts are among the most popular construction schedule types—and for a good reason. They help you visualize your project schedule and make locating the critical path much easier.
Gantt charts typically consist of a calendar with activities and details about them spread out across start and end dates.
What are Gantt charts good for?
Gantt charts are very helpful for finding new ways to look at your project, which will help you identify the best path toward completion. They also simplify the management of projects that involve many overlapping activities. The bar layout makes it very easy to shuffle projects around if overlapping proves to be an issue.
Gantt chart functionality is found in many construction software programs, like Microsoft project. This makes it easy for even laymen to understand your project’s progress.
Gantt chart disadvantages
A Gantt chart will quickly become confusing if you have a massive project with hundreds of tasks simultaneously. The bar layout also does not provide context for how much work and resources are required to complete a particular task—only how long it’s expected to take.
Gantt charts are also impractical for large projects, given how difficult it can be to print all relevant information on a reasonable amount of paper.
6. LAST PLANNER SYSTEM (LPS)
The Last Planner System sees the specificity and detail of your schedule increase as the project deadline approaches. With the Last Planner System, workers start with the deadline in mind and then work backward to identify strategies for accomplishing each milestone.
What is the Last Planner System good for?
The Last Planner System works very well in situations where collaboration between team members is strong. Team members must try to adequately coordinate completion at each phase of the project. This coordination will take place during “pull plan sessions.” An experienced leader is required to keep these meetings on track.
Last Planner System disadvantages
The Last Planner System tends to exacerbate faults in your team’s cohesion. You may want to try increasing collaboration in other areas (such as workforce planning) before betting the success of entire projects on the fruits of pull plan sessions.
7. CRITICAL PATH METHOD
The critical path method is perhaps the most popular of all methods for scheduling in construction management. It involves identifying the resources and time required to complete a milestone and how the set goal is relevant to the overall project.
What is the critical path method good for?
The critical path method is valuable when you’re looking to identify the most appropriate sequence in which a project’s tasks must be completed. As its name suggests, it also helps identify the most critical “branch” of your project’s path, allowing you to easily see which tasks are essential for project completion and what are merely supportive of those tasks.
Critical path method disadvantages
The critical path method may not be the only construction schedule you rely on. This is particularly true on projects involving hundreds of interdependent tasks. While you may identify a critical path in such a scenario, you may fail to adequately account for resources required by tasks dependent on those within the path.
In other words, the critical path method is not a one-size-fits-all solution for scheduling construction projects.
What type of construction schedule is right for you?
As any construction professional knows, choosing the right type of schedule is essential for successful project completion. Each schedule type has strengths and weaknesses, and the best choice for a given project depends on various factors.
For example, the Critical Path Method is well-suited for large projects with many interdependent tasks. At the same time, the Program Evaluation and Review Technique is more appropriate for projects with uncertain task durations.
Line of Balance is often used in construction projects, as it helps to ensure that tasks are completed on time. Meanwhile, the Critical Chain Method has been gaining popularity in recent years, as it helps mitigate disruptions and the effects of delays.
Regardless, carefully considering which schedule is right for the project is important.