I’ve got interesting question from on of my blog readers and it is: “Let’s say that you have Task 1 and Task 2. Task 2 can start when 25% of Task 1 is completed, and Task 1 can continue after task 2 is completed. Is there an option to make such relation and such split (not manually)?”
I will show you that in MS PROJECT 2019!
This is classis Finish to Start relationship. If I want Task 2 to start after 25% of Task 1 is completed, it is not possible. Why? MS PROJECT calculate successor’s Start date depending on many things like Calendars, Exception dates, Task relationship type (for example, Finish to Finish is not the same as Finish to start), but it does not calculate successor’s start date depending on predecessors completeness. But you can make that Start date of Task 2 is 25% after Task 1 start date like this:
Notice that I put 4 days for Task 1 duration just to show you that Task 2 will start 1 day latter then Task 1 (which is 25% of duration of Task 1).
If you insist on Finish to Start relationship you can do the following:
So Task 2 will start 75% before Task 1 is finished which is 3 days, e.g. 1 day after Task 1 start date.
BUT! This has nothing to do with % completeness. In both pictures above Task 2 should start 1 day after Task 1 should been started, no matter if it was started or not!
The other question was is it possible that Task 1 can continue after Task 2 is finished? It means that Predecessor can be worked on after successor is completed! And here I can’t show you example because it is just impossible! First , it is impossible to establish two or more different relations between two Tasks, and second it is impossible to control work on one Task depending on completeness of the other Tasks!