Arguments over who owns the float in the project schedule are common. But unless the contract documents state otherwise, float belongs to whichever party that uses it first. This fact makes no one in particular happy, but a very smart lawyer once told me that the perfect settlement is the one that both parties regret the next day.
Sharing the float is a fair solution, although there will always be times when it seems rather inequitable. The contractor waits until the last possible moment to submit a shop drawing; now the architect is under pressure to return the shop drawing in a timely fashion. The contractor ate the float, making the review critical. But at one time this path had plenty of float. The architect is not happy being put on the spot.
Conversely, the contractor submits the shop drawing very early, but the architect sits on the shop drawing for such a long time that all the float is gone. Now the contractor has no leeway in terms of procuring the materials. Any hiccups during fabrication and delivery will mean the contractor is blamed for the delay, yet he tried so hard to stay ahead of schedule.
As a construction consultant I am caught in the middle. My contractor clients want to own the float, and so do my owner clients. Making people unhappy seems to be part of my job. Nevertheless, it is universally recognized that float belongs to the project. Either party can utilize the float while it is still up for grabs.
There is one brief period of time, however, when only the contractor owns the float. He alone decides how much float each and every activity has in the project schedule. So when is this magic moment? It is quite simple: until the original plan is published the contractor has complete control over the float. Pity then that so many contractors squander the opportunity.
The contract documents clearly give the contractor ownership of means and methods. Certainly there may be some specified sequences in the contract documents (such as for project closeout) but otherwise the contractor decides how to build the project. And this means the contractor controls the float in the original plan. He overlaps work that he feels like overlapping, or makes the work more linear because he wants to conserve resources.
In my experience roughly one-half of all activity relationships in a project schedule are discretionary. We sometimes call these “soft” relationships because the work could be sequenced more than one way. Mandatory (or “hard”) relationships, on the other hand, cannot be violated. The wall has to be built before it can be painted, for example.
When the owner reviews a project schedule only the mandatory relationships can be verified easily. The other half of all the relationships are harder to discern. Why is the contractor starting brick work on the east elevation? Does feeder conduit have to start before branch conduit? But as long as the sequence represents what the contractor intends to follow, the owner has no valid objection. It is what it is.
As with any subject there are a few caveats. I have seen some pretty strange restrictions in contract documents that do affect how logic – and therefore float – can be applied. On one of my projects there was a restriction on what percentage of activity relationships could be Finish-to-Start. Yet on another project I was instructed to use only Finish-to-Start relationships. As a master scheduler I rather resent anyone telling me how to use my tools.
Otherwise, the contractor has so many opportunities to reduce the float in the schedule. Nothing can be considered unreasonable unless it is completely unrealistic. Pour the sidewalks next to the building before starting light poles in the parking lot? Why not? Whether the same trade is involved is immaterial. It is all about hitting dates that make the contractor happy. Besides which, owners often question why activities do not start on their early start dates regardless of the available float.
There is one loophole to consider. The owner and the contractor agree to share the float, per the contract documents. This does not preclude the contractor from crafting language in his agreements with subcontractors to restrict the use of float. In other words, the contractor only has to share the float with the owner. He is not obligated to share float with subcontractors.
Starting with my first scheduling position in 1983 I was told to monitor excessive float. In some cases it is a sign of bad logic. I either had the wrong predecessor (thereby starting too early) or the wrong successor, which allowed the activity to finish late in the project. If I thought the start date was too early I would go shopping for another predecessor that was finishing later than the current predecessor. Similarly, I might look for another successor that starts earlier than the current successor.
Some of you might think this is dishonest, that I am hiding float that otherwise should be there. No, quite the opposite. I am concerned that the float is unrealistic. Who in their right mind would say to a subcontractor, “you can show up as early as March 2nd or as late as September 15th”? Such a range of dates implies uncertainty. I suspect that Primavera P6 introduced two new date columns – Start and Finish – to avoid the confusion of early versus late. Hardly anyone other than experienced schedulers truly understands the concept of float. Trust me.
So we are not “sequestering” float, which is perhaps a nicer term for hiding it. Moreover, I am not a fan of using activity constraints to reduce the float on an activity. Excessive constraints are the bane of my existence. I once spent an afternoon with a client explaining why he needed to get rid of all 150 constraints in his 175-activity schedule. He had originally contacted me because he could not find the critical path. Duh!
When I conduct my final review of the project schedule I consider whether the activities on the critical path make sense. Contract documents sometimes restrict the percentage of activities that can be on the critical path (hint: add more non-critical activities such as submittals if you have too many critical activities). But I must also consider whether activities on secondary paths have too much float. Yin Yang.
There is certainly no worse feeling than a project schedule that seems to suck up all delays due to excessive float. We should not be sharing float that does not really exist. Once the schedule is published it is simply too late to rectify this problem. The float now belongs to the project.
