Primavera P6 calendars support more realistic schedules by allowing for non-working time, holidays, etc. Here we’re taking a look at modifying calendars in Primavera P6.
To modify a Primavera P6 calendar, we’re first going to open our project ‘New Home Construction’ and then select the calendar option, as shown in Figure 1.
In the list section of the Calendars dialog, we can select any of the existing calendars and make changes to them using the modify button on the right-hand side of the screen, as shown in Figure 2.
When we select the modify button, we’re presented with an interactive visual calendar. Using the arrows at the top we can navigate to a specific year, month and date. We can make changes to a date by selecting it and then modifying it to either a Non-work or a workday status using the appropriate button on the right-hand side of the screen.
We can also modify a date in the calendar by double-clicking on it, this will change the specific date to a non-working day, by clicking on the same date again will return it to a working day. Non-work days are shaded in the interactive calendar as shown below in Figure 3.
The two radial buttons at the top of the screen allow us to change the work hours display format. We can view them as ‘Total work hours/day’ as shown in Figure 3 or as ‘Detailed work hours/day’. The ‘Detailed work hours/day’ format displays the hours of the day in 30-minute increments and these are often useful for displaying work breaks in the day or for shift start and end times, as shown in Figure 4.
To make every weekend a non-working day, we don’t need to go through every weekend throughout the year instead we can click on the ‘Workweek’ button on the right-hand side of the calendar dialog.
Upon clicking, we are presented with the ‘Calendar Weekly Hours’ dialog where we can declare the non-working days as well as the working hours per day. We just enter the number of hours worked for each day of the week, using a zero for non-working days, as shown in Figure 5.
Returning to the visual interactive calendar, non-working days that have been set in the Workweek dialog can be made working days on an ad hoc basis by double-clicking on the date. A working day that is ordinarily a non-working day is known or classed as an ‘Exception’ date.
For example, if we want to make a Saturday a working day, we can double-click on it in the calendar and it becomes an exception, if we wanted to make every Saturday in March an exception we just click on the header (Sat).
Previous and future months will not be affected by this change and will remain as non-working days, as shown in Figure 6.
When we click on the ‘Time Periods’, on the right-hand side we enter the ‘Hours Per Time Period’ dialog. We can define the default calendar hours for each time period. Activities and resources assigned to this calendar will use these values as conversion factors when users enter or display units and durations in time increments other than hours.
For example, if a colleague entered a duration as a 1w (1 week), Primavera P6, will view the Hours Per Time Period and calculate how many hours are defined for 1 week, hence calculating the activity duration accordingly as shown in Figure 7.
Therefore, if we change the calendar from an 8 hour to a 10 hour working day, we must adjust the ‘Hours Time Period’ dialog as well as the calendar ‘Weekly Hours’ dialog to avoid seeing incorrect default units time values during resource assignments, as shown in Figure 8.
Care should be taken when modifying calendars in Primavera P6, as any changes may have cost and duration implications for the project. Any alterations in the schedule made either by yourself or another member of the project team that are not hourly increments, have to be addressed in both the Weekly Hours and Hours Time Period to reflect a true schedule.
In this article, we have used a global calendar to demonstrate modifying calendars in Primavera P6, however, any changes made in a global calendar will change any other project assigned to the global calendar.
If you are not working with a similar project or with a project portfolio, we recommend that you use a Project calendar where any modifications that you make to your calendar will only affect your current project.