CSLB General Building (B)Planning and EstimatingMedium
A project manager is developing a schedule for a large commercial renovation. The plumbing rough-in must be completed before the electrical rough-in can begin, and the electrical rough-in must be completed before drywall can start. This type of relationship between tasks is known as a:
- AFinish-to-Start relationship
- BFinish-to-Finish relationship
- CStart-to-Finish relationship
- DStart-to-Start relationship
Show answer & explanationAnswer & explanation
Correct answer: A. Finish-to-Start relationship
A Finish-to-Start (FS) relationship means that a successor activity cannot start until its predecessor activity has finished. In this case, plumbing (predecessor) must finish before electrical (successor) can start, and electrical (predecessor) must finish before drywall (successor) can start.
Why the other options are wrong
- B. Finish-to-Finish means the successor cannot finish until the predecessor finishes, but they can run concurrently.
- C. Start-to-Finish means the successor cannot finish until the predecessor starts, which is rarely used in construction.
- D. Start-to-Start means the successor can start as soon as the predecessor starts, not necessarily finishes.
Finish-to-Start (FS) Relationship
A logical dependency where the successor activity cannot begin until the predecessor activity has completed.
- Most common type of dependency in construction scheduling.
- Ensures sequential order of tasks.
- Example: Foundation must finish before framing can start.
Memory trick: When one task must 'finish' for the next to 'start', that's the FS rule, right from the heart.