Constraining tasks to start on a new day

When you reschedule a project, the start date of a task is determined by the finish date of its latest predecessor task. This is illustrated below, where the start date of task C is set by the finish date of task A:

Three tasks; the start date of task C is set by the finish date of task A

The start date of task C is now the same as the finish date of task A

Before the reschedule

After the reschedule

Note that in the illustrations above, the reschedule moves task C so that it starts midway through Wednesday afternoon, because this is when task A finishes. Although this is logically correct - the link logic shows that task C can start as soon as task A has been completed - this may not reflect the way in which tasks are worked on in real life. Depending on the type of task, it may be very unlikely that someone would start work on a task midway through an afternoon; it may be much more likely that they would start work on the task at the beginning of the next day.

You can reflect this in your projects by constraining tasks to start on a new day, rather than at unrealistic times such as midway through an afternoon. In the example above, if task C were to be constrained to start on a new day, rescheduling the project would result in it starting on Thursday morning, rather than midway through Wednesday afternoon, as illustrated below:

Task C now starts on Thursday morning, rather than on Wednesday afternoon

What constitutes the start of a new day is determined by the calendar that has been applied to a task. If a task has no calendar applied to it, the start of a new day is deemed to be midnight.

You can constrain individual tasks to start on a new day, and you can configure projects so that all new tasks start on a new day by default.

  1. Right-click the task and select Properties. The Bar and Task Properties dialog appears.
  2. Click the Task tab.
  3. In the Constraints section of this tab, select the Start on new day check box to force the task to start on a new day following a reschedule, or clear the check box to allow the start date of the task to be set according to the finish date of its latest predecessor - even if this means that the task starts midway through a day.
  1. On the Project tab, in the Properties group, click Bar Chart Defaults. The Bar Chart Defaults Properties dialog appears.
  2. Click the Task tab.
  3. Select the Start on new day check box to force new tasks to start on a new day following a reschedule, or clear the check box to allow the start date of tasks to be set according to the finish date of their latest predecessor - even if this means that the tasks start midway through a day.

Related Topics:

Using constraints

Constraining tasks to complete within a single time period, shift or work pattern