Which scheduling tool is a better fit for your situation: Primavera P6 Professional or Microsoft Project?
Students often ask whether Primavera P6 or Microsoft Project is more advantageous. My response is biased, of course, and I say Primavera P6 Professional. I will normally mention, off the top my head, a Primavera P6 advantage or two to support my statement. Realizing that my response could be more instructive, I decided to log Primavera P6 advantages over Microsoft Project as I came upon them in practice.
Of course, to be fair they are both very capable tools, and undoubtedly a Microsoft Project expert could construct a similar list of advantages for Microsoft Project over Primavera P6. However I’m a P6 expert more than I am a Microsoft Project expert, so you can take the following for what it’s worth from that perspective.
This article lists and describes the advantages of the Primavera P6 Professional scheduling software tool over Microsoft Project. It is not meant to be a definitive or exhaustive pro/con analysis treaty of the two software programs.
It is more of a reminder of the reasons I have come to appreciate and respect using Primavera P6. And possibly be a starting point in the discussion of both software scheduling tools, although I don’t think this debate will ever end.
1. Top-Down Scheduling
Primavera P6 Professional is more suited to top-down scheduling than Microsoft Project. What does that mean? Specifically, what is a top-down scheduling tool? It means that in Primavera P6 you consider first the end product or deliverable that is the whole purpose of the project.
In support of this effort precedence ordering Primavera P6 has you first input the Work Breakdown Structure (WBS), which is a hierarchical breakdown of all the project deliverables. Only after you have clearly defined the end product or deliverables do you begin to consider the activities required to produce those deliverables.
Microsoft Project is geared more towards a bottom-up approach thanks to it’s use of indenting activities to build a WBS hierarchy, where you first consider your tasks. Typically, only after defining numerous tasks do you ask yourself which of these tasks have a common thread or purpose? These tasks then are grouped together underneath a summary task, which is the equivalent of the WBS element and deliverable in Primavera P6 Professional.
2. Level of Effort (LOE) Activities
Primavera P6 Professional has LOE activities that can span the entire duration of the project. LOE activities are helpful in modeling or scheduling activities that do not specifically produce a deliverable, i.e. WBS element. Examples of LOE activities include administrative and project management efforts. Administrative and project management activity efforts contribute to indirect project costs that are generally not immaterial.
Primavera P6 automatically accounts for progress on these efforts as the schedule is progressed. One nice feature of LOE activities is that they expand and contract as the schedule activities they are tied to lengthen and shorten in duration.
It is possible to somewhat mimic a LOE activity in Microsoft Project by ‘Paste’ linking the respective LOE task to the start of the first task and finish of the last task in a series. This is sometimes called a ‘hammock’ activity being that it is suspended between to points by relationship links. It is unfortunate though that Microsoft Project does not automatically progress the LOE task with schedule updates.
Primavera P6 Professional, as stated above, does update LOE activities in accordance with schedule status updates. So the Microsoft Project linked pseudo LOE activity looks great until the project schedule is progressed.
3. Longest Path
Primavera P6 Professional has a longest path critical activity definition, which is a huge plus. Schedule optimization has the greatest impact when you shorten activities along the longest path. Many times the longest path and critical path coincide. In situations where a schedule has activity constraints the critical activity definition may result in more critical activities that are not necessarily along the longest path.
Project constraints may also cause the scheduling software to display either too many critical paths or completely hide the critical path. In these situations it is best to set the definition of critical activities to longest path. With the longest path definition you know any delay along this path impacts the project end date. And shortening the duration of any activity along this longest path should contract the duration of the whole project. Yes, I often miss longest path when working with Microsoft Project scheduling software.
4. Multiple Float Paths Analysis Feature
Knowing the longest path through the network is definitely good. But what about the second longest path? Or third longest path? Subcritical paths through the network can easily become the longest path with only minor delays. Primavera P6 Professional has a multiple path feature that starts with the longest path, then calculates 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.
Primavera P6 Professional has a feature, not found in Microsoft Project, called activity steps. This Primavera P6 steps feature provides two advantages
- It minimizes Gantt chart activity clutter
- It provides a discrete way of measuring schedule progress
Gantt chart clutter happens when you have a series of small tasks displayed on the Gantt chart. Instead of these numerous related small tasks, the detail is represented by a series of steps, rather like a to-do list for the activity, each weighted according to its relative effort.
Steps are particularly applicable to efforts that do not require a particular order of occurrence, or where the order of occurrence is not easily predicted. Steps also provide a discrete method for measuring progress, as they can be set at 0% complete or 100% complete by a simple toggle.
They can even have a percentage of completion value applied in order to earn part of their percentage of completion. For example, if a step describes the arrival of two job site trailers, and only one arrives, the step can be progressed to 50%, earing exactly that percentage of its weighted value in terms of the activities percentage of completion.
6. Budgeted Material Cost
It may seem to be a minor point, but it is important. Primavera P6 Professional has a field for displaying the budgeted material cost; Microsoft Project does not. Microsoft Project, however, does not leave you without hope though. Microsoft Project provides the ability to insert Visual Basic Applications (VBA) subroutines, which can be programed to isolate and display the budgeted material cost. The Microsoft Project cost field or column displays the sum cost of both labor and material. The VBA subroutine is required to isolate the material cost from the cost field.
So, yes, budgeted material cost is possible to display in Microsoft Project, but doing so requires a herculean effort compared to Primavera P6 Professional. A possible takeaway is if you want to become proficient at Microsoft Project scheduling, learn how to create and apply VBAs in Microsoft Project. So it would be fair to say here that Primavera P6 doesn’t allow for VBA modifications to its workings, so if this is a factor for your implementation, there’s one-up for Microsoft Project.
7. Start and Finish Milestones
Milestones are those little diamonds that appear on the Gantt chart. Though graphically small they represent major effort events in the schedule. Milestones are like markers on a hiking trail telling you definitively where you are on the trail map. Yes, Microsoft Project has milestones but unlike Microsoft Project, Primavera P6 Professional distinguishes between start milestones and finish milestones.
So Primavera P6 Professional milestones tell you more than that you are upon a major event: P6 start milestones tell you where you are going and P6 finish milestones tell you where you’ve been. Thus, Primavera P6 milestones are like directional arrows on a trail marker pointing you forward and/or backward on the trail.
8. Work Formula Types
Both Primavera P6 Professional and Microsoft Project use the following work formula:
In Primavera P6 your selection of ‘duration type’ affects which variables in this work formula are fixed and which are calculated. In Microsoft Project it is the ‘type’ field that specifies which variable is fixed. Primavera P6 has four duration types: ‘Fixed Duration and Units’, ‘Fixed Duration and Units/Time’, ‘Fixed Units’, ‘Fixed Units/Time’. Note that Units in Primavera P6 is work and Units/Time is effort. With ‘Fixed Duration and Units’ and ‘Fixed Duration and Units/Time’ two variables are known and/or fixed and the third is calculated.
In the planning stage when duration estimates are fixed and budget unknown it is good to use ‘Fixed Duration and Units/Time’ duration type. After budget approval the project becomes both cost constrained in addition to time constrained, and the preferred duration type becomes ‘Fixed Duration and Units’.
Microsoft Project expects the scheduler to provide two work formula inputs and Microsoft Project calculates the third. With Project’s type options duration, units (effort), or work it is not abundantly clear which of the two remaining variables is fixed.
So Microsoft Project’s type setting is not as clear as Primavera P6’s duration type setting. Both affect computations in the work formula. You may have to experience work formula computations in both Primavera P6 and Microsoft Project, but having used both I find Primavera P6 work formula computations to be more reliable, i.e. more predictable.
Primavera P6 Professional has a top-down deliverable-activity paradigm that directs the focus of the project planning to the end product and deliverables, which are the whole purpose for the project. In other words it places more emphasis on the work breakdown structure during the development phase of the schedule. Microsoft Project is more suited to a bottom-up task-deliverable approach.
Primavera P6 also has practical features, like LOE activities, Longest Path, Multiple Float Paths, and Steps, which make it a compelling alternative to Microsoft Project. Although Primavera P6 has a steeper learning curve at first for beginners, I say it is less challenging to become an advanced Primavera P6 scheduler than an advanced Microsoft Project scheduler.
Primavera P6 does not require a VBA to separate and list material costs. Primavera P6 duration type (work formula application) is less confusing.
You may also want to consider Primavera P6’s structured approach to progressing the schedule versus schedule progression in Microsoft Project. That is to say that P6 enforces a more structured approach to moving remaining work into the future – whereby Microsoft requires some extra steps to make remaining work move ahead of the status date.
One disadvantage to Primavera P6 Professional is its slightly steeper learning curve for beginners, but its advanced tools make it more suited to describing and analyzing the true project schedule situation.