DOES THE PROJECT COMPLETION DATE MEET CONTRACT REQUIREMENTS?

Check the contract documents to make sure the scheduled completion date meets all contract requirements. Also make sure the completion date meets the management team’s require- ments. With most projects you have the right to complete earlier than the contract requires. This would decrease project overhead costs. Does the management team want to consider this? Even more important, does the project’s total duration feel right? Don’t get so scientific with scheduling that common sense is overlooked. A good “gut check” is to simply ask, does the total duration make sense and seem right based on past construction experience? If it does not, double-check the logic and durations of the critical path until it looks right.

Compressing the Schedule

If the original schedule is too long or as it is updated it goes beyond the contract comple- tion date, it becomes necessary to compress the schedule. Compressing the schedule is also called “crashing” or “shortening” the schedule. Generally, compressing the schedule results in one or more of the following: higher costs, lower quality, or a less-safe work environment. That must be kept in mind as the schedule is compressed. What is the best method to use that will have the least negative impact on the project and the people doing

Chapter 11 • Reviewing and Analyzing the Schedule 103 21 2 23 21 0 23 Sub Slab Plumbing 23 2 25 23 0 25 Final Grade for Slab 25 2 27 25 0 27 Termite Poison 27 3 30 27 0 30 Backfill 30 21 51 Frame 30 0 51 Window Wells 21 2 23 25 4 27 14 7 21 FRIPS Foundation 14 0 21 FRIPS Footings Excavate 9 5 14 9 0 14 5 4 9 5 0 9 21 5 26 22 1 27 Cure Foundation 21 3 24 24 3 27 Damp-proof Foundation

the work? Some managers have tried to come up with more scientific methods with spreadsheets and graphs to make these decisions, but generally, a good conversation with the management team will do the job most efficiently. The three following items need to be considered when compressing the schedule:

1.Changing the durations of critical and near critical path activities. It is obvious that if the

durations of the critical activities are shortened, the project completion date will also be shortened. Less obvious is that the path or string of activities with low float may also need to be revised. If the schedule is to be shortened by 15 work days, it is neces- sary to shorten not only the critical path by 15 days but also every other path where there is 15 days or fewer of shared float. Of course, this typically increases resource demands of more workers and possibly equipment, which may consequently affect productivity and increase costs. Another option that may be considered is to go to multiple shifts for a short period of time on critical activities. Don’t forget to also assess the impact that shortening durations may have on quality and safety.

2.Changing the calendar to have selected critical path activities work on the weekends or holi- days. This choice obviously requires the additional costs of overtime, but typically

has less effect on creating additional safety problems or decreasing quality. Another method, if there are a sufficient number of workers available, is to work people 11.5 hours per day for 3.5 days, which gives them their 40 hours. Then work another crew 11.5 hours per day for the other 3.5 days. A crew works for 3.5 days and then has 3.5 days off. This provides for 80 hours of work on the job. Of course, this would be done only on the critical path activities. That way no one works overtime, but productivity will suffer due to the long work days. Think creatively about other work hour adjustments that might be acceptable to solve special problems.

3.Revising the schedule logic to have more or longer lags and/or more concurrent critical activ- ities. If the logic can be changed to take a critical activity off the critical path and

make it concurrent or even to create an additional critical path, that will take days off the total project duration. This probably was not desirous in the original planned schedule, but in order to decrease the project duration it may be the best choice. This choice may create crowded conditions with the additional concurrent work taking place, but still may be the best choice. Also where there is a lag between critical activ- ities, if the overlap is increased the project will finish earlier. Again, consider the effects of this choice on costs, quality, and safety.

Expanding the Schedule

Expanding the schedule is doing the opposite of compressing the schedule. If it is desirous that the project finish later than the first draft, you would consider the same choices as above but to increase rather than decrease the total project duration. Another reason to expand the schedule would be to decrease congestion or decrease total project costs through improved productivity by giving people more room in which to work. If the draft schedule is quite tight, expanding the schedule may decrease costs.

As the schedule is expanded, the noncritical activities will have more float. This allows for more opportunity to level and manage resources. The more float in a schedule the more flexibility. Also, having additional activities with more float decreases the risk in the project. The more critical activities or higher percentage of critical activities the more likely there is to be delays.