CPM Scheduling Basics Every Contractor Should Know

CPM scheduling maps activities, durations, and logic ties to identify the longest path—the critical path—that drives project completion. Activities on that path have little or no float.

Why it matters: if a critical activity slips, the project finish date slips. Non-critical activities have float and can absorb some delay without moving the end date—until float is used up.

A usable CPM is more than a bar chart. It needs realistic durations, correct predecessors/successors, and calendars that reflect working days. Overly optimistic schedules create credibility problems with owners and lenders.

Update the schedule as work progresses. A baseline without updates becomes wallpaper. Statusing percent complete and remaining duration keeps the critical path honest.

Arch Estimating provides CPM scheduling support, including Primavera and Microsoft Project style deliverables, for contractors who need a clear plan they can share with project stakeholders.