Tips for Using Mixed Calendar Schedules in Primavera P6 version 8.2
When a project has mixed calendars, say an 8- and 10-hour per day, then a change of calendar from a predecessor on an 8-hour per day calendar to successor on a 10-hour calendar, the successor activity may have one hour of work on the same day as the predecessor and span 2 days.
This situation leads to interesting Float calculations and confusion to schedulers.
Primavera P6 does not have a “Start on a New Day” function found in other products such as Asta Powerproject, but which in itself brings on a new set of calculation issues.
Techniques that may be considered to ensure one-day activities span one day and two-day activities span two days, etc. are:
- Apply an appropriate lag to the relationship, or
- When the Start and Finish Times are not an important scheduling consideration then assign all the calendars the same Start and Finish time but adjust the duration of the lunch break so the days have the desired number of hours. For example, a 10-hour day calendar could start at 07:00 and finish at 17:00 without any lunch break and an 8-hour calendar could start at 07:00 and finish at 17:00 and be assigned a 2-hour lunch break.
The picture below shows how 8-hour a day and 12-hour a day calendars in the same project may be set up to ensure all activities start and finish on the same day: