Sample P6 Schedule Layout for Top 3 Float Paths

Once a suitable network has been developed, with duration and resources assigned to all activities, it is necessary to review the longest path through the project before baseline schedule is established. Scheduling Software will simply tell you where the longest path or critical paths are. Normally, a critical path should be extended from the beginning to the end of a project. Review the longest path or critical path(s) using float path layout and validate those activities on critical paths with project team to ensure it makes sense to them.

It is not easy to analyse critical path activities in case you have more than three thousand activities in your project. By having float path layout, the most critical activities or nearly critical activities can be easily reviewed to identify high risk activities when schedule risks are assessed.

When the project is underway, these activities can be thoroughly reviewed with the contractor and prioritized to take corrective action as defined using this float path layout. As this layout is important, especially for the project management team, it may be used as part of the monthly or fortnightly report.

Sample Layout to Find External Links and Broken Logic (No Predecessor or Successor)

Activity with no predecessor or successor in the schedule does not drive the whole project. With the exceptional case, there may be some activities without predecessor or successor such as project start milestone, project finish milestone and an external link activity such as civil work completion of other project.

For example; equipment delivery on site date (equipment supplied by Owner/EPCm Contractor) could be an external link if you are a Constructor with both of you and Owner/EPCm schedule are internally linked. A quick way to identify the broken logic and external date activities is to create a layout and run the report as and when required.

The advantages and disadvantages over Retained Logic vs. Progress Override Option in P6

While Retained Logic and Progress override are the two options available in P6 which enable the scheduler to analyse in different scenarios, each option has advantages and disadvantages.

Retained Logic Option

Advantages

1. It produces the most realistic schedule if the levels of detailed information are available and schedule logic were design appropriately. It maintains all predecessor relationship and will not allow the remaining portion of an in-progress task to resume until its predecessor complete. Fig-1 (Foundation work begins as the work front available, but it is not allowed to start remaining work until piling work complete on the remaining piles).

Tutorial-How to generate S curve/histogram from Primavera, P6 - Part I

The following steps should be done before S curve is generated.

1. Establish WBS
2. Adding activities, Activity codes, Activity sequencing
3. Define resource dictionary
4. Assign activity resource and budgeted man hour
5. Save as a baseline schedule
6. Record the actual status when the actual works are done and schedule it based on report date

Plan data can be produced if the steps 1 to 5 are done. The Actual data can also be exported if all the steps are done. Suppose you have already done all these steps as we are learning how to generate S-curve/ Histogram chart from P6 in this post.