I’m often asked how a project manager can schedule a task to be used to forecast his or her time spent managing a project, with the catch being that the task automatically expands or contracts as the project’s finish date fluctuates. Since there’s no feature or setting native to MS Project to accommodate this need, my advice is that the schedule owner use a technique called a hammock task.
The hammock task technique will allow a specific task’s duration to span the duration of the entire project (or simply a section of the project). To prepare for this task, the project must have two milestones from which the scheduler can “hang” the Start Date and the Finish Date of the hammock task.
In the image below, notice that the Project Management task in this schedule, a common candidate for a hammock task, has a Duration that spans the Duration of the entire project. Also present in this schedule are the Software development START and Software development COMPLETE milestones, which, as previously stated, are required to create the hammock task.
To accomplish this, I completed the following steps:
- Validate that the Task Type of the Project Management task to Fixed Units.
- Select the Finish cell for task ID #1, the Software development START milestone task.
- In the Clipboard section of the Task ribbon, click the Copy button.
- Select the Start cell for task ID #2, the Project Management task.
- In the Clipboard section of the Task ribbon, click the Paste pick list button and select the Paste Special item.
- In the Paste Special dialog, select the Paste Link option and click the OK button.
Figure 1: In the Clipboard section of the Task ribbon, click the Paste pick list button and select the Paste Special item.
Figure 2: In the Paste Special dialog, select the Paste Link option and click the OK button.
- Click anywhere outside of the selected cell.
Notice the little gray triangle in the lower right corner of the Start cell for the Project Management task. This indicates a pasted link for another cell in this project, a cell in an external project, or a cell in an Excel spreadsheet.
Figure 3: Notice the little gray triangle in the lower right corner of the Start cell for the Project Management task.
- In similar fashion as the above, select the Start cell for task ID #88, the Software development COMPLETE milestone task.
- In the Clipboard section of the Task ribbon, click the Copy button.
- Select the Finish cell for task ID #2, the Project Management task.
- In the Clipboard section of the Task ribbon, click the Paste pick list button and select the Paste Special item.
- In the Paste Special dialog, select the Paste Link option and click the OK button.
Microsoft Project automatically calculated the Finish Date and Duration of the Project Management task so that it now spans the Duration of the entire project.
Figure 4: Microsoft Project automatically calculated the Finish Date and Duration of the Project Management task so that it now spans the Duration of the entire project.
Once these actions have been taken, the Duration and the Finish Date of the Project Management task will update based on the movement of the project’s final milestone, Software development COMPLETE, and the schedule owner will no longer have to manually update the Project Management task’s duration.
As a final thought, the reason I’d set the Task Type of the Project Management hammock task to Fixed Units was to make sure that the automation of the task’s duration produces the correct amount of assigned hours should the task need to increase its duration. For instance, if the PM was only working 50% on this task over the duration of the project, any new days added to the task to accommodate the outward movement of the Software development COMPLETE milestone would apply the correct number of hours per day (such as 4hrs per day at 50% of an 8 hr workday).
Happy scheduling!
