Project Management

Define a resource's working time and availability

Modeling a resource's availability is a tricky business for any project manager, but Microsoft Project helps you do it with the Project Calendar feature. Learn how with the latest installment of our Project series.


Microsoft Project is great for defining a project’s available resources, but the process can be a bit complicated. In part one of this series, I examined the basic fields involved in defining a resource and its costs in Project. Here, I’ll describe how to define a resource’s working time and the tricky business of modeling a resource’s true availability.

Figure A shows the Working Time tab of the Resource Information dialog box. This is where you define a resource’s working calendar. The Base calendar field lets you pick a project calendar as the basis of the resource’s working calendar. This will usually be the same as the so-called Project calendar in the Project Information dialog box. You can get to this dialog box by going to the Project menu and clicking Project Information.

The Project calendar lets a project manager define the working and nonworking days for the whole project team. All resources that use this calendar as their base calendar will automatically have the same default working days and times. The Working Time tab of the Resource Information dialog box lets you make changes to the default values on a case-by-case basis.

Figure A


In Figure A you can see that the example resource’s working calendar uses the Standard calendar as its basis. All the Saturdays and Sundays are nonworking time as set by the Base calendar. So is Monday the second of September. The project manager defined it as a nonworking day (the Labor Day holiday) in the Standard calendar. September 25-27 show an edit to the working calendar for this particular resource. These might be days when the resource will be on vacation, in training, or otherwise unavailable to work on the project.

Before designating a day as a nonworking day for a particular resource, check to see if it’s a nonworking day for all resources. If so, make the edit in the Base calendars that these resources use. This will reduce the total number of edits you need to make. To designate a nonworking day, select the day in the calendar and click the Nonworking Time radio button to the right of the calendar.

You can model a resource’s work shifts in the From and To fields in Figure A. This resource’s calendar shows work scheduled from 8:00 A.M. to 12:00 Noon and then again from 1:00 P.M. to 5:00 P.M. to make an eight-hour working day.

Modeling availability
The process of modeling work shifts raises the question of modeling the availability of resources. No matter how much we might not like it as project managers, it’s impossible for our resources to spend all of their time on projects.

Resources will have to do things like attend meetings, answer e-mails, use the phone, and take breaks. Project managers have several ways to address this issue:
  • Reduce the Max Units value to account for all the other things besides project work. Many organizations set Max Units to something like 80% or 75% to compensate for these necessary distractions.
  • Insert “overhead” tasks into projects, and assign resources to these tasks for about 20% of their working day to model the work done on these other things. When resources report their time, the project manager can see how much time is spent on project work and how much on other things.
  • Manipulate the working calendars and “hours per day” settings in Project to show that, while a resource actually worked an eight-hour day, Project only sees a seven-hour day. This way, the other hour doesn’t even show up in Project.

My first choice is the first option, “reduce the Max Units value.” It’s quick, easy, and effective. Inserting overhead tasks requires effort on the part of the resources to account for every minute of every day, which can make them feel that “Big Brother” is watching. It also assumes that resources would be completely honest and not just report that all eight hours went into your project.

The third choice, manipulate the working calendars, is the second-best solution, but it’s one that requires an unrealistic view of the working day. To set the working times for the default day so that there are only seven hours instead of eight means that you’re saying the day ends at 4:00 P.M. instead of 5:00 P.M., which isn’t the case. This is an issue if you have time-sensitive tasks that are due close to the end of the day. According to your project plan, a one-hour task started at 3:30 P.M. would be pushed to finish the next day because you’ve told Project that the day ends at 4:00 P.M. In reality, workers are still there working until 5:00 P.M.

The first option lets you keep your calendars technically accurate and still account for all the other things that can affect resource availability. You need to decide on a method that works for your project and for your organization. It’s best if all the project managers in an organization use the same method to model availability. It makes for easier portability of project plans and an easier transition to a resource pool environment.

Those are the basic elements of entering your resources. In later articles, I’ll examine similar best practices for defining tasks, tracking actual hours, and analyzing project progress.

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