TOPIC: Critical Path Delays: Free Float / Total Float

Can you help clarify critical path delays and options using free float/total float.

If I find an activity delay on the critical path , and I want to try to use similar resources from other activities to help my delay. If my choices is to use Free Float from one activity or Total Float listed from another activity, which should I use? Free Float activity? Total Float Activity? Both?


Thanks

As far as I have understood your question, you are telling if there is a potential delay on one of the critical path activity, can you manage the situation by assigning more resources to this activity so that the activity finishes on the planned time and there is no delay to the project?

Yes, you can do that. This technique is called crashing.

Now the second question, from which activity or activities you need to pluck these resources out? From wherever you pluck out these resources, it will affect those activities. You must get these resources from non-critical activities (i.e. activities with float) so that the overall project doesn’t get delayed. It is preferred to use the free float first as that only delays that particular activity. However, usually most of the activities don’t have sufficient free floats. In that case total float can be used.

Please let me know if this clarifies you confusion?

Warm regards,

Khurram

So if I get a PMP exam scenario question that stipulates that I am behind on the schedule, and I need to improve the situation, and my choices are
a) Free Float from Project A, b) Total Float from Project B c) Both Project A and B.

Would the answer be "a" or "c"?

I guess I need to understand what would be the best answer in this scenario? And understand when it would be Free Float only vs both? Can you give numerical scenario examples if the answer would vary depending on a scenario?

Thanks

(continued from above) However, usually most of the activities don’t have sufficient free floats. In that case total float can be used.

For example, if I have a 3 day delay.
Are you saying if my free float is 3 days or more use, that would be my first choice. I should exhaust my free float days first and the remaining balance to take from the total float?

Thanks for the clarification with a numerical example

Exactly! You are right!

If the question doesn’t give you numbers, then we have to make an assumption that the delay can be handled either with a free float on Project A or total float on Project B. In that case the best answer is the “free float” because consuming free float doesn’t affect any activity other than from where the free float is being taken out.

However if the scenario gives numbers, first you need to determine if the free float can handle the delay (i.e. available free float is greater than potential delay). If yes, then “free float” is your answer. If not, you still need to consume the free float before you use the total float. In this case, the answer would be “free float and total float both”.

Let me know if this resolves your concern.

Regards,

Khurram

Yes. Thank you.