By Kent Winger, PE, Rachel Martin, PE, and Erick Espinosa
The project construction schedule is a critical tool for managing project risks and achieving timely completion. For owners, clear specifications, a proactive scheduling approach, and effective administration throughout the duration of the project can assist with providing early notification of job problems and delays. Owners may then be able to take measures to mitigate these issues. For contractors, an accurate schedule is important for properly planning and executing the work in a cost-effective manner. In addition, a properly progressed and updated schedule serves as a record of when the work occurred, the sequence of the work, and how long the activities took to complete. These, and other schedule-driven goals, can be more readily achieved when an owner and contractor agree upon a baseline schedule.
The baseline schedule should reflect the contractor’s best planning efforts to complete the work in accordance with the contract documents at the time of bid. Establishing a reasonable and logical baseline schedule allows for a level playing field from which to start regularly evaluating progress and, if necessary, contemporaneously apportioning responsibility for delays that may arise during construction. The owner and contractor should work together collaboratively to agree upon a reasonable baseline schedule, even if it takes several revisions of the original schedule to reach consensus regarding its content. As the project schedule is usually one of the first submittals required by the contract specifications, this partnering effort can set the tone for project success.
There are best practices for owners and contractors to consider when developing and approving a baseline schedule. Foremost is that the schedule be in compliance with the scheduling and work constraint specifications. Owners should develop a schedule specification checklist spreadsheet to help review for proper compliance with the contract requirements. Here are other key considerations that can enhance the development and approval process.
- Verify that there are adequate details in the schedule to address all aspects of the required construction effort. For example, each building component, or mechanical, electrical, or structural system upgrade, should have its own series of work activities. Contractors should draw upon their experience from similar types of projects and have those who bid the job also participate in the development of the baseline. Owners should develop a list of risks that may impact critical milestones and review how those risks are modeled and addressed in the baseline schedule. For example, the schedule should clearly indicate when owner-furnished equipment is needed at the jobsite. If the owner-furnished equipment is late, the risk is that the project may be subject to a compensable delay.
- The baseline schedule narrative should explain the planned work sequencing, work areas, schedule restrictions, and assumptions. For example, if different work calendars are used in the planning, the contractor should explain why those calendars are used. Also, details need to be provided in order for a reviewer to understand what assumptions were used to develop the schedule. If changes to the work occur later, these assumptions may assist with establishing entitlement for a change order.
- Finally, try to avoid using constraints and lags in the scheduling software. These scheduling techniques often hinder an analysis of the longest path (or critical path) of the work. The contractor should model activities with logic and durations that drive the milestones rather than using constraints. Both parties should agree what activities comprise the longest path. Later in the project, it is difficult to determine whether the critical path of the project is being delayed when there were flaws in the initial logic.
In conclusion, a properly prepared project baseline construction schedule is an important tool for managing risks and achieving timely completion. Several key factors to consider during the development and approval of the baseline schedule are:
- The baseline schedule is in compliance with the scheduling and work sequence specifications.
- The schedule contains adequate details of the construction effort.
- The schedule addresses the risks perceived by the owner.
- A detailed written narrative is provided explaining the assumptions and the basis for the schedule.
- The schedule portrays the longest path without the use of lags or constraints.