The critical path displays activities that have a total float of zero or less, which is often referred to as the longest path. But what about multiple float paths? A path that is the next longest path: i.e. near critical, potentially critical and so on? Is there a way in Primavera P6 Professional to list project paths in order of length, i.e. in order of critical importance? Well I doubt you’ll be surprised if I say “Yes, there is”.
The critical path is an important concept in scheduling a project. By most standard critical activity definitions the critical path is the path through the network where a delay of any activity along the critical path delays the end date of the project.
Project managers definitely want to watch progress of critical path activities. In tight multiple path schedules, however, project managers may want a more in-depth analysis of the differing paths through the schedule. It may be helpful to know the next or nearest longest path, which could easily become the critical path due to activity delays.
This article discusses how to analyze a Primavera P6 Professional schedule with multiple float paths.
Primavera P6 Professional has a multiple float path feature that starts with the critical path, then calculates additional float paths in descending order of length, i.e. order of importance. So paths are listed in order from longest to shortest or most critical to least. This multiple path analysis feature is particularly helpful to analyze or keep track of schedules that have multiple float paths all in a narrow activity total float range.
Below in Figure 1 is our demonstration project schedule.
Figure 1
This schedule has three apparent paths, but one critical path. We want a more in-depth analysis of float paths, so we select the options button in the schedule tool, Figure 2.
Figure 2
In the advanced tab, Figure 3, toggle ‘calculate multiple float paths’.
Figure 3
Set the feature to calculate multiple paths using total float. Set the display multiple float paths ending with activity J, which is the last activity in the schedule. You may also set the number of paths to calculate. Our schedule appears to have 3 paths, so we set this number of paths option to 3.
The resulting report is displayed in Figure 4.
Figure 4
Note the float path and float path order columns in the activity table are both populated. In Figure 5 we set the group and sort feature to group by float path, which groups float paths in descending order of importance.
Figure 5
The resulting report is displayed in Figure 6.
Figure 6
The critical path with zero total float activities is listed first. Next comes the float path 2 that has one day total float. This is followed by float path 3, which has two days total float. This multiple float report is particularly useful as a delay of as little as three days on any of these paths can make that path the critical path.
This example demonstrates the value in generating a multiple path report; it warns us to keep watch of other near critical paths in addition to the critical path.
Summary
The longest path or critical path through the network is an important scheduling concept to understand as it tells you the shortest possible time frame for your project. It also spotlights in red the activities that cannot be delayed without delaying the end date of the project.
Most projects have more than one path through the schedule network. A multiple float path report may warn of a non-critical path’s potential to become the critical path from only minor activity delays along its path. A multiple float path report lists network paths in order of length or importance providing a more robust analysis of the actual schedule situation.