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A Baseline Critical Path can have float! best way to show it?

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John Reeves
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A Baseline Critical Path can have float! best way to show it?  Example, I worked on project where half the scope was removed before it started but the completion date did not change.  There is a school of thought you just stretch to fit to get 0 Float, that would be silly in the case I noted.  To be honest, end dates are backed into and random and there really is float commonly.  Biggest question?  How to show it?  There are people who cannot understand it at all unless it is a red path with 0 float, even schedulers.  There are people who will make a float or contingency bar at the end to make it red and 0.  Or use a constraint date either in the project or in setup.  Personally I think the best way is to use coding to make the longest path red and add a text column that states "CRITICAL PATH", but you see the float.  Other ways mess up the math or confuse the real end date.  What do you think?

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John Reeves
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Thank you for the comments, you guys are great!

Rafael Davila
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Early Completion Schedules

Ghost Schedule

At home we do not use the NEC and Early Completion Baselines are prohibited to the extent if you submit an Early Completion Schedule it is interpreted as a reduction in contract duration. Therefore we submit a schedule that uses all contract time and keep a Ghost Schedule we call it our optimistic schedule.

Late Completion Schedule 

I recall a case where we submitted a Late Completion Schedule on the basis that for a critical delivery the Brand Name Specification material delivery was preventing the schedule from finish within contract date. Prior to bidding the supplier provided his quotation but was reluctant to provide a delivery schedule.

Rafael Davila
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Contractors’ float in ECC programmes

Terminal float: Under NEC 3 contracts the period between planned completion and completion date is owned by the contractor under the contract. NEC 3 requires all submitted schedules to show reasonable terminal float and any schedule lacking terminal float might be rejected as targeting for a schedule with no terminal float is considered bad practice as this means close to 50% of the time you will not make it.

You can show terminal float as a hammock while showing float based on Planned Completion Milestones as shown in this sample schedule. 

  1. Fix Contract Completion Milestone using start and finish constraints equal to the contract completion date and set it to not consider in scheduling. Do not fix this milestone using activity links.
  2. Apply contract finish date to Planned Completion Milestone.

As a user of Spider Project I mostly look for float calculation that do not tweak the late dates but also have access to negative float values calculated by such tweak as a separate field.

terminal-float-01

terminal-float-02
click thumbnails

However if using the software resource leveling most software longest path and float calculations will be unreliable.


Good Luck

Zoltan Palffy
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in p6 your can define the number of days that you want to be critical if you float is 5 days just set it to 5 days or less. You can set the critical path be to be the longest path.

One thing that I do is create a activity code called CP then I filter for the last activity can then I look at the predcessor window and I look for the predcessor that is both driving and critical and highlight it and then I select goto and then this activity is added to the view I keep doing this until i get back to the data date then I assign all of those activities the CP code. now i can filter for the CP activity code and I have the true critical path,