Setting up task predecessors correctly

Question

Using Open Project (or MS Project, i suppose), in the following example:

• does #13 depend on #7?
• does #14 depend on #7?
• does #13 depend on #12?
• does #14 depend on #12?

Or does it matter at all? Please assume waterfall

Answer 1

7,9,13, & 15 are "Summary Tasks", or "Roll-Up" views. They're combinations of other tasks (9 is the sum of 10,11,12, and 7 is the sum of 8,10,11,12), not tasks in and of themselves. So no, they would not have predecessors.

12 is a task, and can have a predecessor.

So for your questions -

1. No. 14 would follow (depend) 8. Both 13 and 7 are summary tasks.

2. No. 14 would follow 8. No 13 is a summary task.

3. No. 14 would follow 12. 13 is a summary task.

4. Yes. See above.

Answer 2

And to add to Trevor's explanation, you have both hard predecessors and soft predecessors. A task can have a finish start relationship because the first task MUST finish before the second begins. That is hard logic. But you can also have the same logic based on a resource constraint or other scheduling logic. That would be considered soft logic.

Every leaf level task or package should have a predecessor-successor relationship somewhere in the schedule. No task should be orphaned. That way, your ability to manage a critical path or two will not be compromised.