Microsoft Project Tutorial: Know Your Task Type

As soon as you assign resources in Microsoft Project, the task type determines how the task is scheduled.

To set a default task type for the entire project, click Options on the Tools menu, and then click the Schedule tab. In the Default task type box, select Fixed Units (the default), Fixed Duration, or Fixed Work.

To change the task type for an individual task, select the task, and then click the Task Information button on the Standard toolbar. Click the Advanced tab, and then in the Task type box, click the task type that you want to create.

Work, duration, and units (% allocation) are determined by the formula: Work = Duration * Units. The formula kicks in when you assign the Resources to the task.

You can change the task type of a task during your maintenance of a project plan. Before making a change to a task, ask yourself, “Once I make this change, what do I want Project NOT to change?” Whatever the answer is, set the task type to fix that variable before making the change. Example: You’re about to add a 2nd resource to a task. Ask yourself, do I want the Duration to stay the same, or do I want the units (% each resource works) to stay the same? Whatever you want to stay the same, set that to Fixed, before adding the 2nd resource.

The handy tables following, should help you understand Microsoft Project’s behavior and choose the correct Fixed variable for your purposes.

Basic Equation and Table relating to Work, Duration and Units

Comparison between Effort Driven and Non Effort Driven Tasks

Note: The following items are important to understand Microsoft Project behavior.

1. Changing the Units of a resource to 0% falls under Changing Units and not under Removing Resource category. Therefore, there is a difference in how Microsoft Project behaves in the two cases – Remove Resource Assignment and Decrease Units of a Resource to 0%.
2. Changing the Units of a resource from 0% falls under Changing Units and not under Assign New Resources category. Therefore, there is a difference in how Microsoft Project behaves in the two cases – Assign new Resource and Increase Units of a Resource from 0%.