Free Float vs. Total Float

Attribute	Free Float	Total Float
Definition	Amount of time an activity can be delayed without delaying the project	Amount of time an activity can be delayed without delaying the project completion date
Calculation	Subtracting Early Start of the next activity from Early Finish of the current activity	Subtracting Early Start of the current activity from Late Start of the next activity
Impact on Project	Does not affect project completion date	Affects project completion date
Management	Managed by the project manager	Managed by the project scheduler

Definition

Free float and total float are terms commonly used in project management to describe the amount of time a task can be delayed without affecting the project's completion date. Free float refers to the amount of time a task can be delayed without delaying the early start of any successor tasks. Total float, on the other hand, refers to the amount of time a task can be delayed without delaying the project's completion date.

Calculation

Free float is calculated by subtracting the early start date of a task from the early start date of its successor tasks. If the result is zero, it means there is no free float for that task. Total float, on the other hand, is calculated by subtracting the early start date of a task from its late start date. If the result is zero, it means there is no total float for that task.

Importance

Free float is important because it helps project managers identify tasks that can be delayed without impacting the project's schedule. By knowing the free float of each task, project managers can prioritize tasks and allocate resources more effectively. Total float, on the other hand, is important because it helps project managers determine the overall flexibility of the project schedule. Tasks with more total float are less critical to the project's completion date.

Impact on Schedule

Free float has a direct impact on the schedule of a project. If a task's free float is reduced or eliminated, it can cause delays in the project's timeline. Project managers need to closely monitor tasks with limited free float to ensure they are completed on time. Total float, on the other hand, has a more indirect impact on the schedule. Tasks with more total float can be delayed without affecting the project's completion date, but excessive delays can still have a negative impact on the project's overall timeline.

Resource Allocation

Free float can help project managers allocate resources more efficiently. By identifying tasks with more free float, project managers can prioritize resources on critical tasks that have limited flexibility. Total float, on the other hand, can also impact resource allocation. Tasks with more total float may not require as much attention or resources as tasks with less total float, allowing project managers to allocate resources more effectively.

Risk Management

Free float can help project managers identify potential risks in the project schedule. Tasks with limited free float are more susceptible to delays, which can increase the overall risk of the project. By closely monitoring tasks with limited free float, project managers can proactively address potential risks and mitigate their impact on the project. Total float, on the other hand, can also help project managers manage risks. Tasks with more total float provide a buffer against unexpected delays, reducing the overall risk to the project's completion date.