Logic link
Logic links describe the relationships between one activity and another.
Common types of logic link include:
- Finish-to-start: One activity cannot start until a previous activity has finished.
- Lagged finish-to-start: One activity cannot start until a specific amount of time after a previous activity has finished.
- Start-to-start: One activity cannot start until another activity has started.
- Lagged start-to-start: One activity cannot start until a specific amount of time after another activity has started.
- Finish-to-finish: One activity cannot finish until another activity has finished.
- Lagged finish-to-finish: One activity cannot finish until a specific amount of time after another activity has finished.
- Lagged start and finish: One activity cannot start until a specific amount of time after another activity has started, and it cannot finish until a specific amount of time after that activity has finished.
- Negative lag: One activity can start a specific amount of time before another activity has been completed.
- Must start / must finish. The activity must start or finish on a specific date.
Ref The Society of Construction Law Delay and Disruption Protocol, 2nd edition, published in February 2017 by the Society of Construction Law (UK).
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