What is Slack Time?

Slack time is an interval that occurs when there are activities that can be completed before the time when they are actually needed. The difference between the scheduled completion date and the required date to meet the critical path is the amount of slack time available. The project manager should always be aware of where slack time exists in a project, since this time can be used to reshuffle the schedule to support the critical path.

Example of Slack Time

For example, if there is slack time in a task not located on the critical path, resources can be shifted from that task to tasks located on the critical path, thereby bolstering the most crucial tasks.

Slack Time Best Practices

You should keep track of the trend in available slack time for each task. If the trend is declining, it can indicate that work is taking longer than expected. By spotting these trends, you are in a better position to investigate and determine why work issues are occurring. This can result in the timely reallocation of resources to maintain a reasonable amount of slack time within the system.