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CPC Certified Professional Constructor study materials
CPC Certified Professional Constructor study resources

CPC Certified Professional Constructor: Planning, Scheduling and Time Control: CPM, Float, and Delay

CPC Certified Professional Constructor · Work through your exam, one topic at a time.

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Planning, Scheduling and Time Control: CPM, Float, and Delay

Planning, Scheduling and Time Control tests whether you can build a logical schedule, calculate time, and use the schedule to manage the job. Expect CPM, float, resource management, progress updates, and delay analysis.

Building the schedule

  • Start with a WBS and an activity list. Define durations, logic, lags, and calendars.
  • A network uses dependencies: finish-to-start is common; start-to-start, finish-to-finish, and start-to-finish also appear.
  • The critical path is the longest duration path through the network; it sets the project duration and has zero total float in a simple network.
  • Total float = late start - early start or late finish - early finish. Free float is the time an activity can slip without delaying the next activity.
  • Resource leveling may change the critical path; resource smoothing tries to avoid that. Crashing adds cost; fast-tracking adds risk.

Worked example

Activities: A duration 3, no predecessor; B duration 5 after A; C duration 2 after A; D duration 4 after B and C. Forward pass: A ES 0, EF 3; B ES 3, EF 8; C ES 3, EF 5; D ES 8, EF 12. Backward pass: D LF 12, LS 8; B LF 8, LS 3; C LF 8, LS 6; A LF 3, LS 0. Total float: A 0, B 0, C 3, D 0. Critical path: A-B-D, duration 12. C can slip 3 days without delaying D. If B slips 2 days, the project finish moves to 14 unless B is compressed or logic changes.

Updates and delay

  • Update with actual start, actual finish, remaining duration, and logic; do not simply overwrite the baseline.
  • Percent complete should reflect physical progress, not cost spent.
  • Delay analysis distinguishes excusable, non-excusable, concurrent, and compensable delay.
  • Look-ahead schedules translate the master schedule into short-interval work plans.

Traps

Calling the most expensive path critical; assuming total float belongs to the contractor; mixing calendar days and workdays; ignoring lags and constraints; treating a schedule update as a baseline revision; and measuring progress by cost alone.