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How to manage tasks with variable duration / amount of work RRS feed

  • Question

  • Hello,

    I'm currently trying to build a macro planning for my department for the next 2 years.

    In my plan, there is a task that has a variable duration and amount of work. People will start / stop working on it depending on the beginning / end of other tasks. The only way to do this I've found so far is to split the task into multiple subtasks (one per resource) that are manually scheduled with start and end dates linked to the dates of the tasks they depend on. However, I think this workaround is really not practical and hard to manage since for each subtask I need to create milestones for linking the start date to the next working day. Relationships between tasks are also not visible in the plan. I've also read that in general it' better to avoid using links, but is there a better way to manage this in Project 2013 ?

    Best regards,

    Sébastien.

    Sunday, March 2, 2014 11:52 AM

Answers

  • Hi (again) Seb,

    I'll suggest to use only one task, assign all resources on this task, and use the task usage view, so you can manually enter work on different timeslot for each resource in the "excel-like" timephased grid.

    Hope this helps.


    Guillaume Rouyre - MBA, MCP, MCTS

    • Marked as answer by Seb_Lz Monday, March 3, 2014 9:46 AM
    Sunday, March 2, 2014 3:46 PM
    Moderator
  • Seb_Lz2,

    Okay, "external" means outside of the project file, so you threw us off by using that term. Secondly, as soon as I read the word "macro" I thought of VBA, since that is the normal context, but after reading further I think by "macro" you actually meant "the big picture". Funny how terminology can lead to misunderstanding.

    Okay, so as I understand it you have this one unique task. You've stated it is important and that many resources are required to complete it but the detail is still missing so I'm not sure what that task really is. Going back and reading your original post it almost sounds like that task, although required to complete the project (e.g. documentation), is really fill-in type work that can be done whenever resources are available to work on it. Other than your original workaround approach, perhaps another approach might be to treat it as a normal task and then manually edit the work, actual and remaining, as the project progresses.

    John

    • Marked as answer by Seb_Lz Monday, March 3, 2014 9:46 AM
    Monday, March 3, 2014 12:53 AM

All replies

  • Hi (again) Seb,

    I'll suggest to use only one task, assign all resources on this task, and use the task usage view, so you can manually enter work on different timeslot for each resource in the "excel-like" timephased grid.

    Hope this helps.


    Guillaume Rouyre - MBA, MCP, MCTS

    • Marked as answer by Seb_Lz Monday, March 3, 2014 9:46 AM
    Sunday, March 2, 2014 3:46 PM
    Moderator
  • Seb_Lz,

    There are several elements of your description that need more detail.

    You mention a variable duration. That could simply be a normal task that changes scope as the plan progresses (i.e. more work content, slipping schedule, etc.), or it could be indicative of what is called a hammock task (See Faq 19 on the MVP website at: http://project.mvps.org/faqs.htm).

    You mention linking as a way to define task dependencies. That is exactly what task predecessors and successors are designed to do. Task links have nothing to do with resources. It's not clear why you say only one resource per task.

    You talk about manual scheduling and entering start and finish dates. Manual scheduling is intended for a very rough first cut at a working schedule. To get the full benefit of Project's scheduling engine, tasks should be auto-scheduled and the whole logic network sequence of tasks should be defined by durations and links, not by manually entering dates. It's fine to set critical milestones or use Project's deadline feature, but otherwise let Project tell you how your plan all works given the basic data.

    You say relationships are not visible in the plan. Don't understand that at all since link lines between tasks are shown by default in task views (e.g. Gantt Chart view).

    Not sure where you read that it is better to avoid using links because that is flat out wrong, at least for normal predecessor/successor links within a single file. If you are working with a linked structure (i.e. master/subproject), or using external predecessors/successors, then yes, links become a whole new area of concern.

    John

    Sunday, March 2, 2014 4:06 PM
  • Hello Guillaume,

    This is what I'm currently doing, however if for some reason the dates of the other tasks it depends change, I have to edit again manually my planning. It's an acceptable solution but I was wondering if there existed a more automated way of doing it. Thanks for your reply.

    Sunday, March 2, 2014 4:28 PM
  • Hi Seb,

    Maybe I missed something but why don't you simply use one task per assignment (per resource), linking them with relationships (as John said, it is actually adviced to use predecessors and successors) and grouping them under a summary task? In this way,

    • you'll see the dependencies in the Gantt chart,
    • it will be easier to manage than splitting the task and clearer to visualize,
    • the schedule and assignments will automatically be updated when changing assignment duration.

    Hope this helps.


    Guillaume Rouyre - MBA, MCP, MCTS


    Sunday, March 2, 2014 4:40 PM
    Moderator
  • Hello John and thanks for your reply.

    The subtasks I'm referring to are indeed hammock tasks. When I'm talking about "links", I mean dynamic links that fetch a value for a cell from  external sources (the start/end dates of others tasks in my example). I'm aware of the successor/predecessor fields and use them as much as possible. However in my situation, I'd need to do something like setting a predecessor and successor per resource and tell the engine of Project that these resources will work on the task after and/or before some others tasks (depending on the resource).

    Hope this clarifies things a little more.

    Sunday, March 2, 2014 4:45 PM
  • Seb_Lz2,

    Tell us more about those dynamic links. What is generating those external start and end dates? Is it another Project file, an Excel file, or something else?

    Again, predecessors and successors apply to tasks, not resources. Tailoring work periods for resources should generally be done with custom resource calendars.

    It would help if we could understand your end goal. Oftentimes a user will post a question on how to do something a specific way without providing the overall context. Given a better understanding of the end goal, a better solution may be possible.

    John

    Sunday, March 2, 2014 4:57 PM
  • John,

    The external dates are generated by the end and start dates of other tasks in the same project file. Concerning predecessors and successors, I know they only apply to task but it's a way to illustrate what I'm trying to achieve.

    My macro planning contains tasks with a fixed duration or work amount except for one of them. It's an important task that will require many resources. However, I don't want this task to shadow all the other ones. Therefore I want to add some constraints related to the time periods my resources will work on that task. I also want to visualize how much work is still available for that task if we keep all those constraints. As the project progress, we will have a better estimation of the required work for the task and be able to detect whether we need additional resources or delay. 

    Hope this gives a better overview of the context.

    Sébastien.

    Sunday, March 2, 2014 5:57 PM
  • Hi Seb,

    Maybe I missed something but why don't you simply use one task per assignment (per resource), linking them with relationships (as John said, it is actually adviced to use predecessors and successors) and grouping them under a summary task? In this way,

    • you'll see the dependencies in the Gantt chart,
    • it will be easier to manage than splitting the task and clearer to visualize,
    • the schedule and assignments will automatically be updated when changing assignment duration.

    Hope this helps.


    Guillaume Rouyre - MBA, MCP, MCTS


    Guillaume,

    When I say 'splitting' the task, I mean create one task per assignment, so we are talking about the same thing :).

    Predecessors and successors relationships cannot be used for those tasks since they have a variable duration enforced by linking their start and end dates to the next working day of other tasks in in the project. In fact, I'd like to tell the engine that this task has a predecessor and a successor and that the duration of this task = <successor start date> - <predecessor end date> - 1.

    Sunday, March 2, 2014 6:12 PM
  • Seb_Lz2,

    Okay, "external" means outside of the project file, so you threw us off by using that term. Secondly, as soon as I read the word "macro" I thought of VBA, since that is the normal context, but after reading further I think by "macro" you actually meant "the big picture". Funny how terminology can lead to misunderstanding.

    Okay, so as I understand it you have this one unique task. You've stated it is important and that many resources are required to complete it but the detail is still missing so I'm not sure what that task really is. Going back and reading your original post it almost sounds like that task, although required to complete the project (e.g. documentation), is really fill-in type work that can be done whenever resources are available to work on it. Other than your original workaround approach, perhaps another approach might be to treat it as a normal task and then manually edit the work, actual and remaining, as the project progresses.

    John

    • Marked as answer by Seb_Lz Monday, March 3, 2014 9:46 AM
    Monday, March 3, 2014 12:53 AM
  • John,

    Indeed, at the end of the day, it's maybe the easiest approach. I think I'll do that for now.

    Thanks,

    Sébastien.

    Monday, March 3, 2014 9:45 AM
  • Sebastien,

    You're welcome and thanks for the feedback. I think it boils down to the fact that Project won't do everything a user wants. It is designed to help plan projects for the majority of planning/scheduling scenarios but there are a few scenarios that it [Project] will not lend itself to.

    John

    Monday, March 3, 2014 3:14 PM