Predecessors

Doug B

I have Task A with a fixed start/stop dates

I have Task B with a fixed Start/Stop date

I have Task C that needs to Start the same as Task A, but finish the same as the Stop of Task B.

There are multiple lines available in Smartsheet to add predecessors to a single task.  In my example, Task C shows the correct Finish with Task B but only 1 day duration.  Why the ability to add multiple predecessors to a task if the values do not show correctly?    Thanks.

Mike Wilday

I too would like to know that answer to that question.

J. Craig Williams

Smartsheet does not handle constraints in the same way that (some) other PM tools do. You can have multiple predecessors for either start date OR end date, but not both. 

Craig

Doug B

Thanks Craig.  I'm curious why there are multiple lines available for the predecessors.  What would be the value of having these if only one can be used?

J. Craig Williams

From a purely PM viewpoint, two or more tasks may need to completed before another task can be started (or finished).

The electrician needs to finish the wiring and the plumber needs to finish the pipes before the walls can be finished.

See the Dependencies allows the PM to determine if things can be done in parallel, fast-tracked, if shifting more resources from one task to the another can improve the schedule timing.

This is NOT the same as constraints -  schedule constraints are limitations that impact either the start or end date of a task. For example, Sally can ONLY work on Tuesdays-Thursdays. If the predecessor is completed on the previous Friday, either the task must wait until Tuesday or someone else must do it. 

Some PM tools have a "two of any three" - start date, end date, duration. Give them any two and the third can be calculated. Smartsheet does not allow duration to the dependent variable. (Resource complication ignored)

I hope that helps.

Craig

 

 

CanadaJim

I'd also like to point out that if you split this task into 2 tasks, the first half task can start at the same time as task A and the 2nd half task can finish at the same time as Task B.

Put both these tasks under a parent, and voila!  You have what you want.

The half tasks may not be continuous (may overlap or have a gap), but it's better than what you're working with now.

Jim

Doug B

Thanks Jim, great solution.

Canada Doug

J. Craig Williams

Jim's suggestion does not quite work if you are concerned about resource or  cost management as the key to both of those are duration. Either you will have too much or too little. If you are only worried about schedule management, then it will be fine.

Craig