Task Calendar and Resources – how they fit together in MS PRIJECT 2016?


I had a lot of question about the Topic I will write about today. Basically it is about relations between Resource (with no Calendar, or, to be more precise, which has Standard Calendar assigned), and specific Task with Specific Calendar working time.

I will explain this with MS PROJECT 2016 with Very simple Project, which has only one Task, and only one Resource.


Task has 1 day Duration. Suppose, that for some reason work on Task can be done only from 08:30 to 13:30, and from 14:30 to 17:30 (let’s say for security reasons), and this will apply only for this Task.

First, I will create separate Calendar:




OK! Now I will assign Task Calendar to the Task:


and I will get:


As you can see, duration for the Task is 1 day, but for the Project is 0,94 days (and the Project has only one Task).

As you can see on the right side of the screen Task will be worked on from 08:30 to 17:00.

How to explain this? first, if you choose File->Options->Schedule you will notice this:


In  Task Calendar work can start at 08:30, so it will start at that time. On the Task Calendar, work can end at 17:30, but because the Schedule (see screenshot above) says that end time is at 17:00, the work will end at that time. So, the Task will be worked on from 08:30 to 17:00 with on hour break  from 13:30 to 14:30 (according to the Task Calendar9, and that is 7,5 hours of total work. But, because on Schedule Option it says that it is 8 hours per day, duration for the Project is calculated as 7,5 / 8 = 0,94.

Now I will assign Resource – John to the Task. he has no specific calendar, so he is supposed to work from 08:00 to 12:00 and from 13:00 to 17:00. When I assign him, I will get this (I will show you on the Task Usage View):

  • Monday, 10.07.2017:


  • Tuesday, 11.07.2017:


I will explain this result, step by step:

  1. Task Duration is 1 day, and this is 8 hours of work to be done on it (see 3 pictures above)
  2. John can work from 08:00 to 12:00 and from 13:00 to 17:00
  3. Task Calendar says that on Task work can be done from 08:30 to 13:30 and from 14:30 to 17:30
  4. According to that, John will start to work at 08:30 (because of Task Calendar) and he will work to 12:00 (because of his Calendar), and this is 3,5 hours. He will continue at 13:00 (because of his Calendar) and he will work to 13:30 (because of Task Calendar) and this is 0,5 hours. Then he will continue at 14:30 (because of Task Calendar), and he will work to 17:00 (because of his Calendar) and this is 2,5 hours. So he will work 3,5+0,5+2,5= 6,5 hours at Monday. At Tuesday John has to work remaining 1,5 hours and he will start to work at 08:30 (because of Task Calendar) and he will work to 10:00.
  5. Duration for the Project says that it is 1,19 days. It is confused. Why? Because you will think that the calculation should be 6,5 hours on Monday /8 hours per day (in Schedule options) + 1,5 hours on Monday /8 hours per day (in Schedule options) = 1. But MS PROJECT calculates it like: Monday = 1 day because it was worked on it the whole day (whenever it was possible to work!). On Tuesday it was worked 1,5 hours of 8 available, so it is 1,5/8 = 0,19. Do the Total duration is 1 (Monday) + 0,19 (Tuesday) = 1,19 days

To conclude, it can be confusing, but you should get use to it.



About Nenad Trajkovski

Location: Zagreb, Croatia Occupation: Project Manager Interests: Project Management and MS PROJECT He was born in Zagreb, Croatia at 1963. After completing his college he started working on projects in different business areas (banking, manufacturing, automotive industry, distribution, oil companies, etc.) developing and implementing ERP systems into different companies. He has got a lot of experience working with people in different business processes and also possesses great knowledge in information technologies and financial services. Today he works as a business consultant, adn Project Manager in PERPETUUM MOBILE d.o.o. Zagreb. He is a regular lecturer for Project Management in MS Innovation Center in Varaždin, Logosoft Sarajevo in Bosnia and Herzegovina and SEAVUS GROUP in Skopje Macedonia. He was named the best lecturer of WINDAYS 2008 while his lecture was also voted as the best. In addition, he was in TOP 10 lecturers at the MS SINERGY 2009 and MS VISIA 2009, 2010. Shares first place as the best lecturer of KulenDays 2009 and 2010 and PMI Conference 2009 in Zagreb. He is also a regular lecturer in the MS Community. He is a Certified Accountant and a PMP (Project Manager Professional) and a PMI-RMP (Risk Manager Professional), MCP, MCT, and Microsoft Certified Technical Specialist - Microsoft Project 2010. From 01.01.2012 awarded with MVP (Microsoft Most Valuable Proffesional - Microsoft Project)!
This entry was posted in MICROSOFT PROJECT, Microsoft Project 2013, MS PROJECT 2016, PMI, PRoject Management and tagged , , . Bookmark the permalink.

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