Scheduling as Part of the Project Management Effort - Construction Project Scheduling and Control - page 288

compensate for poor performance or low productivity. The challenge in this
approach is how to implement such days in the baseline schedule. There are
twowaystodoso:
i. Distribute these days evenly along the duration of the schedule : In this case,
the scheduling program treats these days the same as holidays and sched-
uled nonworkdays. This approach may cause some problems in tracking
the project if a certain day is shown on the schedule as a nonworkday
when, in fact, it is not. The advantage of this method is that the schedule
is most realistic in the occurrence distribution of nonworkdays, although
the specific date may be incorrect. As a remedy, the scheduler can adjust
dates for nonworkdays during the update.
ii. Put all 18 days at the end of the project : This method makes the actual
schedule look worse than it is. As the project progresses, nonworkdays
occur but they are not reflected in the schedule, so the schedule looks
like it is behind schedule until the end. At this point, the 18 contingency
days start, and the negative float (up to 18 days) disappears.
One approach used in some organizations, particularly municipal governments, is
to have two different completion dates:
1. An internal completion date : This is the date when the project manager is
responsible to management for completing the project.
2. An external completion date : This is the date when management is responsible
to the client (owner/board of commissioners or trustees) for completing the
project.
The first date is, obviously, the earlier one. The difference between the
two dates is “management float” or “time contingency.” Management uses
that as a bank and authorizes the PM to use days out of it only for a valid
excuse. It is not a good idea for management to exaggerate this time contin-
gency. One possible problem with such an exaggeration is in the timing of
funding. This may be a particular problem for public agencies (municipalities
and local governments). Budget departments may distribute the cost of the
project over its fluffed duration; it then takes less time than officially reported.
This early execution 20 of the project may mean an earlier request for money
than anticipated (even though the total is unchanged) and the agency may
have the money committed for the next, not the current, fiscal year.
Besides using the nonworkdays, the contractor may create hidden float . Hidden
float can be created either by inflating the duration of an activity or by manipulating the
logic. For example, assume that the durations and logic in Figure 10.5a are correct,
20 Not really early but compared to the “fluffed” schedule.