Start to Start Lag

Understanding Start-to-Start Lag in Project Planning & Scheduling

In the realm of project planning and scheduling, ensuring smooth workflow and optimizing resource allocation is crucial. One key concept that contributes to this is Start-to-Start Lag (SS Lag). This article aims to demystify this term and demonstrate its significance in achieving project success.

Definition:

Start-to-Start Lag, or SS Lag, defines the minimum amount of time that must pass between the commencement of one activity and the start of its successor(s). This delay can be expressed either as a specific duration (e.g., 3 days) or as a percentage of the predecessor activity's duration (e.g., 20%).

Why is SS Lag Important?

SS Lag plays a vital role in project planning and scheduling for several reasons:

• Resource Availability: Implementing an SS Lag ensures that the resources required for the subsequent activity become available only after the predecessor activity has been underway for a specific duration. This prevents resource conflicts and facilitates a smooth transition between activities.
• Dependency Management: SS Lag establishes a clear dependency relationship between activities. The start of the successor activity is contingent upon the progress of the predecessor, preventing premature initiation of tasks that rely on deliverables from previous activities.
• Avoiding Bottlenecks: By strategically incorporating SS Lag, project managers can anticipate potential bottlenecks and plan accordingly. This ensures that the project timeline is maintained and that critical tasks are not delayed due to insufficient lead time.
• Improved Project Quality: SS Lag helps maintain project quality by allowing ample time for tasks to be completed thoroughly and for potential issues to be addressed before moving on to the next phase.

Examples of SS Lag in Action:

1. Software Development: Before starting the testing phase of a software project, a minimum of two weeks must pass after the development phase commences. This allows for sufficient code review and documentation to be completed, ensuring a robust and well-documented product for testing.
2. Construction Project: The start of the painting phase cannot begin until the drywall installation phase has progressed for at least 3 days, allowing for adequate drying time and ensuring the painting process is not hindered by damp surfaces.

Key Points to Remember:

• SS Lag can be applied to multiple successor activities, creating complex dependency chains.
• The specific SS Lag value should be determined based on the nature of the activities and the project's overall requirements.
• Utilizing project management software can significantly simplify the implementation and tracking of SS Lag within a project schedule.

Conclusion:

Understanding and effectively utilizing Start-to-Start Lag is essential for successful project planning and scheduling. By strategically implementing SS Lag, project managers can streamline workflow, optimize resource allocation, and ensure the timely delivery of high-quality deliverables. This critical concept empowers project teams to navigate complex dependencies, anticipate bottlenecks, and achieve project goals with greater efficiency.