Finish-to-Finish (FF) Relationship in Primavera P6.

Introduction

The Finish-to-Finish (FF) relationship is another key type of activity dependency in Primavera P6. In this relationship, the successor activity cannot finish until the predecessor activity finishes. This type of relationship allows both activities to run simultaneously, but the completion of the successor depends on the completion of the predecessor.

The FF relationship is useful when two activities are related in such a way that one cannot be fully completed until the other is done, even though they can progress in parallel.

Key Characteristics of Finish-to-Finish (FF) Relationship

Simultaneous Execution:

Both the predecessor and successor activities can be performed concurrently. However, the successor activity cannot finish until the predecessor activity is finished.

Partial Dependency:

Unlike the Finish-to-Start (FS) relationship, the FF relationship doesn’t require the predecessor to be completed before the successor begins. Only the finish of the successor is dependent on the finish of the predecessor.

Suitable for Parallel Workflows:

The FF relationship is often used in workflows where activities must be coordinated to finish together.

Flexible Completion Times:

While both activities can run in parallel, the FF relationship ensures that one can’t be completed until the other finishes.

Real-Life Examples of FF Relationship

Example 1: Construction Project

Predecessor Activity: Complete electrical wiring in a building.
Successor Activity: Complete electrical system testing.

In this case, the electrical wiring and system testing can occur in parallel, but the testing cannot be fully completed until all of the wiring has been installed. The FF relationship ensures that the project is completed efficiently while maintaining the necessary coordination between related tasks.

Example 2: Event Planning

Predecessor Activity: Finish decorating the venue.
Successor Activity: Finish setting up the audio-visual equipment.

In an event planning scenario, both tasks can progress simultaneously, but setting up the audio-visual equipment may depend on the completion of the decoration (e.g., finalizing the stage backdrop). The FF relationship ensures that both tasks finish around the same time to meet the event deadline.

Example 3: Software Development

Predecessor Activity: Finish writing the code for a software module.
Successor Activity: Finish testing the module.

The testing team can begin testing as soon as a part of the module is coded, but the testing cannot be fully completed until the entire module is written and delivered. The FF relationship ensures that testing ends only when the coding task is completed.

Using FF Relationship in Primavera P6

To create a Finish-to-Finish (FF) relationship in Primavera P6, follow these steps:

Define the Activities: Ensure that you have both the predecessor and successor activities defined in your project.
Assign FF Relationship: In the Activity Details window, under the Relationships tab, assign the Finish-to-Finish (FF) dependency to the successor activity and link it to the predecessor activity.
Lag or Lead (Optional): You can introduce lag or lead to adjust the timing of when the successor activity finishes compared to the predecessor.

Lag and Lead in FF Relationship

Lag: Lag introduces a delay between the finish of the predecessor and the finish of the successor. For example, if there’s a 2-day lag, the successor activity will only finish 2 days after the predecessor activity is finished. Example: In a building project, if floor installation (predecessor) is completed, there might be a 2-day lag before final cleaning (successor) can be finished.
Lead: A lead (negative lag) allows the successor activity to finish slightly before the predecessor activity finishes. Example: If the painting of walls (predecessor) is nearly complete, the clean-up (successor) may finish slightly earlier with a lead, assuming the last areas of painting are finishing up.

Advantages of FF Relationship

Improves Project Efficiency: Allows multiple tasks to be worked on simultaneously while coordinating their finishes, improving overall project efficiency.
Flexible Coordination: The FF relationship allows tasks to be coordinated in parallel but only restricts their completion, providing more flexibility than sequential relationships.
Ideal for Complex Projects: FF relationships are useful in complex projects where tasks need to be coordinated to finish simultaneously, such as in construction, event management, and manufacturing.

Limitations of FF Relationship

Potential for Delay: If the predecessor activity is delayed, it may cause delays in the completion of the successor activity as well.
Coordination Challenges: Managing activities that are progressing simultaneously but must finish together requires careful coordination, especially when using lead and lag adjustments.
Limited Application: The FF relationship is not as commonly used as FS or SS, and is more specialized for activities that need to finish together.

Real-Life Scenario of FF Relationship

Example: House Construction

Consider a house construction project where multiple finishing tasks are happening concurrently:

Predecessor Activity: Finish tiling the floors.
Successor Activity: Finish installing plumbing fixtures.

In this case, both tiling and plumbing fixture installation can happen simultaneously in different parts of the house. However, the plumbing fixtures (such as sinks and toilets) might rely on the final completion of tiling to ensure proper placement and avoid damage to the floors. Using a Finish-to-Finish relationship ensures that both tasks complete around the same time without delaying the overall project.

When to Use FF Relationship

Simultaneous but Coordinated Tasks: Use FF relationships when two tasks can run concurrently, but the finish of one depends on the completion of the other.
Interdependent Activities: When one activity cannot be fully completed without the full completion of another, such as in testing and production, FF is ideal.
Project Optimization: FF relationships help optimize project timelines by allowing activities to progress together and only tie them together at the point of completion.

Conclusion

The Finish-to-Finish (FF) relationship in Primavera P6 is a valuable tool for managing tasks that can be performed concurrently but need to be coordinated to finish together. It provides the flexibility to execute parallel activities while maintaining control over when both tasks are completed. By using lag and lead times, project managers can fine-tune the timing of these activities to optimize project schedules, making the FF relationship especially useful in complex and time-sensitive projects.