If you’ve ever created a bar in Primavera P6 and had difficulty displaying it on your Gantt chart the problem may be in where your bar is located in the list or stack of bars.
Let’s say that you create a new bar style for say a ‘Near Critical bar’ to monitor your near critical activities, which is a subset of the Remaining Work bar. You want to display all Remaining Work activities in green and all Remaining Work activities that are also Near Critical in magenta. How can this be done? It appears that you are telling Primavera P6 to make some bars green and other bars both green and magenta. How does Primavera P6 resolve the illogical situation of a bar being specified as both green and magenta? Well, Primavera P6 has a systematic way of determining which color to use when the apparent illogical situation of a two color specification arises.
This article discusses how Primavera P6 computes color designations to resolve the illogical situation where one bar has two color designations.
The Situation
In this demonstration case we have created a magenta colored Near Critical bar to monitor near critical activities, which is a subset of the green colored Remaining Work bar. Our Near Critical activities are defined as any activity with a total float between 0.1 and 10-days long. We select the Near Critical Display toggle in the Bars dialog to display all Gantt chart bars that are Near Critical, Figure 1.
Figure 1
What you get when we activate the Near Critical bar is displayed in Figure 2. No magenta bars appear in Figure 2.
Figure 2
It appears that no bars are Near Critical. A closer examination reveals that the Grade Site activity, Figure 3, has a total float of 4-days, and, therefore, should be highlighted as a magenta colored bar. However, it is not; it is green.
Figure 3
The Mystery Problem
What went wrong? Well, our Near Critical filter is correct, so what is the answer to the mystery as to why the Grade Site activity bar is not magenta. Confident that Primavera P6 has a systematic way of deciding the color of the Gantt chart bars, we look at the Bars dialog, again, Figure 1. You’ll notice the list or stack of defined Bars in the Bars dialog. A clue is the up and down shift buttons on the Bars dialog. With these up and down buttons we can move bars higher or lower in the stack. You’ll notice that the Near Critical Bar is at the top of the stack, Figure 4.
Figure 4
Let’s look at moving the Near Critical bar lower in the stack.
Fixing the Problem
We can lower the Near Critical bar by selecting it and then using the Shift down arrow button, Figure 5, to move the Near Critical bar to the bottom of the stack.
Figure 5
After moving the Near Critical bar to the bottom of the stack the Gantt chart will look similar to Figure 6.
Figure 6
With the Near Critical bar at the bottom of the stack we now have magenta colored Gantt chart bars.
The Mystery Explained
Why are the Near Critical activities now displayed on the Gantt chart? There must be a reason for this change of events? The answer is that Primavera P6 places bars at the top of the stack on the screen first and then overlays any similar bars on top of them. So Primavera P6 has a logical and systematic way of displaying Gantt chart bars.
The solution is to always note where your Gantt chart bar is on the stack, and to know that its placement on the stack makes a difference. Higher bars in the stack are placed on the screen first and lower bars are then overlaid on top of them, if their sets intersect.
Summary
A possibly frustrating mystery is not knowing how Primavera P6 places bars on the Gantt chart. Primavera has a systematic and logical approach to placing bars on the Gantt chart. When bar sets intersect you will see the bar lower in the stack overlaid on top of the bar higher in the stack.
Another bar stack mystery has to do with the relationship arrows between baseline bars verses schedule activity bars. But that was a topic of another blog entitled “Primavera P6: Showing Relationship Arrows Between Schedule Activity Bars and Not Baseline Bars”. The link is here: https://tensix.com/2014/12/primavera-p6-showing-relationship-arrows-between-schedule-activity-bars-and-not-baseline-bars/