Everything you need to know about schedule hammocks

In Primavera, project or phase duration can be represented through a hammock activity which is a level of effort task that spans from start to finish of the project/phase.

Unlike task‑dependent activities, a hammock is not “real work.” It’s a monitoring tool designed to reflect the overall timeframe without distorting CPM calculations.

By linking the hammock to the start and finish milestones (start‑to‑start and finish‑to‑finish), it automatically mirrors the project’s duration. This ensures clarity at both WBS and activity levels, while avoiding the risk of inflated durations that could mislead the schedule.

The key advantage of using a level of effort type is that Primavera ignores it in network calculations. It won’t create false criticality or extend timelines, but it still provides meaningful visibility into the project’s span.

Hammock activities are essential for tracking project duration accurately. They give planners a clean, reliable view of timelines without manually checking related activities or compromising the integrity of the schedule.