Class 102: Types of Construction Schedules

There are many different types of construction schedules, from post-it notes on a wall showing the flow of a project, to schedules produced by artificial intelligence that take into account real-time data from the construction site. According to the Association for the Advancement of Cost Engineering (AACE) Recommended Practice 48R-06: Schedule Constructability Review, a project construction schedule “should be a comprehensive and realistic plan that represents the specific activities, reasonable duration for the activities, and the planned sequence of work for the project. The logic or sequence of work activities should represent how the project will be built and how the various activities are interrelated." 1

To produce a construction schedule, contractors typically use one of the following most common construction scheduling programs:

Primavera P6

Microsoft Project 

Asta Powerproject

Phoenix Project Manager 

Why do we need so many types, and how do we decide what to use?

The type of schedule used is typically driven by the scope and complexity of the project. For a short duration project, like a screened-in porch addition, a simple schedule produced in Excel can be sufficient. However, on a complex project, like a hospital or mixed-use skyscraper, software that calculates the schedule can help organize the project’s plan. Consider the magnitude of work required to construct a mixed-use skyscraper. On any given day, there could be hundreds of laborers on the project site performing various tasks. Some trades are completing their scope of work while other trades are just beginning. The construction schedule is used to keep the moving parts organized.

Regardless of the specific format used, it’s very important that schedules stick to industry best practices. As referenced in “Construction Delay Claims” by Barry Bramble and Michael Callahan, “The 'project schedule' serves different functions and has different meanings to the architects, engineers, contractors, subcontractors, suppliers, owners and courts of law involved in the construction process.”2  Since various groups are reviewing the schedule, schedule consistency is needed so that anyone involved with the project can understand it, not just the group that created it.  

Key Terms: 

1. Construction Schedule – a comprehensive and realistic plan that represents the specific activities, reasonable duration for the activities, and the planned sequence of work for the project.

Resources: 

1. 48R-06: Schedule Constructability Review - AACE International.web.aacei.org/docs/default-source/toc/toc_48r-06.pdf?sfvrsn=4.

2. Bramble, Barry B., and Callahan, Michael T. Construction Delay Claims. Wolters Kluwer Legal & Regulatory U.S., 2017.

Class 101: Introduction to Construction Schedules

A construction schedule outlines the steps needed to complete a project. The steps are broken down into individual components called activities. These activities have relationships between each other that explain the sequence of work within a project. The schedule can define which group (subcontractor, general contractor, owner, etc.) is responsible for each activity and, in some cases, the associated finances and resources.

Example of a Construction Schedule:

The example above shows a typical construction schedule for a high-end mixed-used skyscraper. Consider all the moving components required to construct a complex project such as this one. Without having a detailed, organized and overall clear plan of how to successfully complete the project on-time and on-budget, the contractor would meander through an inefficient sequence of constructing the project. However, developing a schedule with a detailed outline allows for an efficient construction process. 

What are some other reasons to have a construction schedule?

The successful completion of a project is often tied to the quality of its schedule. A schedule is created before construction begins to create an initial plan for completing the project in accordance with contractual requirements. When updated frequently, schedules can track intermediary progress and can identify areas or trades falling behind schedule. Knowing how the project is progressing allows the project team to accurately update plans. Additionally, changes to the design of the project are often made after construction begins. If change orders are issued by the owner, adding the new work to the schedule will show how the changes impact the overall project duration.

Construction schedules can also help resolve current issues, mitigate future issues, and improve estimates and efficiency on future projects. They can help with delay conflict resolution by providing a historical record of the project’s timeline.

According to “Construction Delay Claims” by Barry Bramble and Michael Callahan, “schedules are an important part of proving or refuting delay and other impact claims because they provide a detailed medium for comparing and measuring time and intent. The use of a detailed method to present a time claim is important to carry the claimant's burden of persuasion to establish its entitlement to both the delay and whatever additional costs a delay may have caused. Schedules also substitute a disciplined analysis that can be reviewed and challenged for the judgments of the certifier or claimant. Schedules are increasingly used to prove a delay in the United States and other countries.”¹

Construction Schedule Summary:

    1. Before a project begins, schedules create an initial plan for completing the project in                 accordance with contractual requirements.