0.4Setting Up the Project (Calendar, Start Date)
The essentials in 30 seconds
- Before any task, set the start date (Project schedules forward by default) and the project calendar.
- The calendar defines working days/hours, weekends and public holidays: it conditions all durations.
- A wrong calendar skews the whole downstream schedule: it is the basis not to be neglected.
Running mini-case — Meriem sets the calendar for her site in Algiers
Before entering the slightest task on her R+3 site, Meriem sets up the project. She first fixes the start date in Project > Project Information: Project will schedule forward from that day. She then opens Project > Change Working Time to adapt the company's "Standard" calendar: working hours, weekend off and public holidays declared as exceptions. She tests with a 5-day task: it must skip the weekend and holidays. Finally she checks the scheduling options (manual/automatic mode, duration unit). Without these settings, all the site's dates would be wrong.
Self-contained case for this section: it returns in the lesson, the diagram, the script and the 48h challenge of section 0.4.
1. Two fundamental settings
Before entering the slightest task, you set up the project — a step often neglected that avoids many date errors. Two fundamental settings: the project start date (Project schedules forward from that date by default) and the project calendar, which defines the working days and hours, weekends and public holidays/leave. All durations will be calculated according to this calendar: a 5-day task does not count weekends if they are off.
2. Where to set what
You set the start date in Project > Project Information, and the calendar via Project > Change Working Time (you often start from the "Standard" calendar and adapt it: hours, bridge days, leave). Other scheduling options (File > Options) specify the behaviour: new tasks in manual or automatic mode, default duration unit.
3. A wrong calendar skews everything
This is the crucial point: a wrong calendar skews the whole downstream schedule. A forgotten public holiday or a weekend wrongly treated as working silently shifts the finish dates. The right reflex — Meriem's — is to test a 5-day task just after setting up, to check that the calendar really skips weekends and declared holidays.
🔎 Concrete example — 🔎 Concrete example — The calendar trap
Meriem tests her calendar just after setting it:
A 5-day task started on a Thursday finishes the following Wednesday
(it skips the weekend) and the declared holidays.
→ "Change Working Time": weekends off? leave?Key point: durations are counted in working days, not calendar days.
Lesson: testing a 5-day task validates the calendar before continuing.
Section vocabulary
- Project start date
- Date from which Project schedules (forward by default); set in Project Information.
Simple example: Meriem sets the launch day of her site there.
What it is not: the finish date of a single task.
Reflex: starting point → start date.
- Project calendar
- Definition of working days/hours, weekends and public holidays serving as the basis for calculating all durations.
Simple example: Meriem marks the weekend as off and declares the holidays there.
What it is not: a simple column of dates in the grid.
Reflex: all durations → project calendar.
- Working time
- Time slots considered as worked; set via "Change Working Time" (exceptions, leave).
Simple example: Meriem adjusts the company's working hours.
What it is not: the name of the project file.
Reflex: hours and leave → working time.
- Scheduling options
- Settings (File > Options): mode of new tasks (manual/auto), default units, calculation behaviours.
Simple example: Meriem chooses tasks in automatic mode.
What it is not: the colour of the Gantt bars.
Reflex: task behaviour → scheduling options.
- Standard calendar
- Base calendar provided (often 8am-5pm, Mon-Fri) that you customize for your company/project.
Simple example: Meriem starts from Standard, then adapts it to the construction company.
What it is not: a calendar created from scratch, with no base.
Reflex: start from Standard, then adapt.
In practice — In practice — Set up the project correctly
- In Project > Project Information, set the project start date (forward scheduling), like Meriem for her site.
- Open Project > Change Working Time: adjust the working hours and add public holidays/leave as exceptions.
- In File > Options > Schedule, check the mode of new tasks (manual or automatic) and the default duration unit.
- Test: enter a 5-day task and check that it really skips the weekends and holidays defined.
Step-by-step script — set up like Meriem (5 min)
1) In Project Information, set the start date. 2) In Change Working Time, set the hours and mark the weekend off. 3) Add public holidays and leave as exceptions. 4) Check the mode of new tasks and the duration unit in the options. 5) Test a 5-day task that must skip the weekend and holidays.
Testing a 5-day task is the best check of the calendar.
Copy-paste template — my setup sheet
Running thread: Meriem, project manager — engineering & construction (BTP) company, Algiers.
BEFORE any task:
1) Start date → Project > Project Information (forward scheduling).
2) Calendar → Project > Change Working Time (working days, weekends, holidays).
3) Options → File > Options (manual/auto mode, duration unit).
4) Test a 5-day task: does it skip weekends and holidays?Start date
Meriem fixes the launch date of her site in Project Information.
Weekend off
Meriem sets the calendar so that the weekend is not a working day.
Declared public holiday
Meriem adds a public holiday as an exception in the working time.
The 5-day test
Meriem enters a 5-day task to validate that the calendar really skips the non-working days.
✓ Best practices
- Set the start date and calendar BEFORE any task.
- Declare holidays/leave as calendar exceptions.
- Test a 5-day task to validate the working days.
✗ Common pitfalls
- Entering tasks before having set the calendar.
- Forgetting a public holiday or a company leave day.
- A task/resource calendar inconsistent with the project calendar.
Key takeaways
- Set the project start date BEFORE entering the tasks (Project schedules forward).
- The calendar defines working days/hours, weekends and holidays: it conditions all durations.
- "Change Working Time" is used to customize hours and leave.
- A wrong calendar skews the whole schedule: it is the basis not to be neglected.
48h challenge — apply it tomorrow
Like Meriem, open a project, set the start date and, in Change Working Time, mark the weekend as off and declare a public holiday as an exception. Then enter a 5-day task and check that it really skips the weekend and the holiday: if the dates come out right, your calendar is correct.
- I set the project start date before entering the tasks.
- I configure the calendar (working days, weekends, holidays).
- I test a 5-day task to validate my working days.
Frequently asked questions
Should you schedule from the start date or the finish date?
The most common is to schedule from the start date: Project places the tasks forward and calculates the finish. You schedule backwards only for an imposed, non-negotiable deadline. To begin with, Meriem recommends the start date, simpler and more flexible.
My durations do not come out right (a 5-day task finishes too late). Why?
Almost always because of the calendar. Project calculates in working days: a 5-day task started on a Thursday stretches to the following Wednesday and skips the declared holidays. Check "Change Working Time": weekends off, declared leave, correct hours, and consistency with the task/resource calendars.
What must you set BEFORE entering the tasks?