You may have the best schedule. Your activity duration estimates may be quite accurate. Your schedule logic may be finely tuned to complete the work in the least amount of time. You may have created the perfect schedule, however, if you do not have the resources available to perform the work your schedule is not realistic.
Resources are key to a successful project. Acquiring project resources may require you to negotiate with other managers competing for the same resources. However, before you begin the sometimes challenging process of resource negotiation, let’s explore a number of ways you can deal the over-allocation of a particular resource in Primavera P6 Professional.
You have an important resource that is over-allocated. The easiest and possibly least negative way to resolve this over-allocation in P6 is by simply doubling the Max Units/Time for that particular resource. This is done by highlighting that resource in the resources tab and adjusting the Max Units/Time in the Units & Prices bottom details, Figure 1.
In our demonstration we highlight the Cable Splicer specialist and would then change the Max Units/Time from 10.0h/d to 20.0h/d. This works great! It automatically doubles the availability of your required Cable Splicer resource from one to two. This means that you now have two of this particular resource available to perform the work. And it appears that your resource over-allocation problem is quickly solved.
However, the reality of the situation all too often is that you do not have two of the same resource required for your project. Yes, if your required resource is a common laborer then you might just have four common laborers available to work on the project. On the other hand, if your work requires a resource with specialized skills, as is often the case, then you may only have one of these resources available to your project.
The question then becomes what can be done to eliminate or at least reduce this particular resource over-allocation?
Below are ways to handle this particular resource over-allocation:
Change Activity Relationships
Adjust your activity’s logic relationship so that activities performed in parallel are now performed sequentially. This is the most straight forward approach. Unfortunately, it usually results in lengthening the schedule, particularly, if the activities in question are along the critical path.
Lengthen Activity Duration To Reduce Units/Time
Here you may be asking your resource to work 12-hour days on an activity. To reduce their required daily effort on this activity lengthen its duration, so the daily effort becomes 8-hours per day on an extended activity. Again, problem solved, but your project length, most likely, becomes longer.
Exchange One Resource For Another
Do you really need a specialist to perform all the activities in question? If not you may be able to switch out your specialist for a second resource. However, you should only use this method if the second resource has the skills necessary to complete the activity. This may also delay your activity and, perhaps, the schedule, as your second resource may require a learning ramp up time to achieve full productivity.
Use The ‘As Late As Possible’ Constraint
Here you allow non-critical activities to slip to their latest possible date. This solution is ideal because it does not impact schedule duration. However, the activities in question may remain in parallel resulting in causing the same resource over-allocation problem at a different time. Never-the-less, if possible, this has the least negative impact, so it definitely should be investigated.
Accept The Over-Allocation
If the over-allocation is not too significant you could ask the resource in question to work over-time. This increases labor cost, and may wear out your specialized resource, but it is a commonly used method.
Reduce The Budgeted Units/Time Allocation
Here you reexamine or renegotiate your specialist’s required daily effort. Perhaps, your specialist does not need to work 10-hour days to complete the activity on time. Perhaps, your specialist only needs to work 5-hour days. So you negotiate with your specialist team member to reduce their daily effort and more accurately represent their required daily output.
As you can see, when your specialized resource is over-allocated you have many possible ways to handle this situation. So before you go negotiating with other resource managers for more resources or before you go and hire a new resource consider the many ways to remove or reduce this resource over-allocation.
The issue with many resource over-allocation remedies is that they, most likely, will lengthen your project. Using the ‘As late as possible’ approach is favorable because it attempts to eliminate over-allocation within available float; it will not lengthen your project.
Yes, accepting the over-allocation and asking your resource to work overtime is a common and legitimate approach. Before you do this though reexamine the estimated required daily effort of your resource.
Perhaps, in reality only a part-time effort is required when the estimate specifies a full-time effort. Allocating resources to produce a realistic schedule is a major duty of the project manager.
Adroit project managers will consider the many ways of resolving resource over-allocations before entering the sometimes challenging resource negotiation process with other resource managers.