How should you determine the activity duration in the baseline schedule?

In scheduling, we often face the equation:

Labors = Quantity / (Duration×Productivity)

Quantity is fixed, and productivity depends on your company’s conditions.

That leaves two variables: duration and number of labors.

• Scenario 1: Assume manpower → calculate duration.
• Scenario 2: Assume duration → calculate manpower.

The right approach is Scenario 2. Projects run on deadlines, not on your available crew size. Start with a reasonable duration based on project constraints, then calculate how many workers are required.

Example:

• 100 m² of tiling in 1 day.
• Productivity = 100 m²/day per worker.
• Required = 1 labor.

If deadlines tighten, shorten duration and increase manpower accordingly.

👉 Bottom line: Always assume duration first, then calculate the required resource.

It keeps your schedule realistic and aligned with project timelines.