Instead of planning from back to front—arbitrarily selecting precedence relationships and task durations— to make the project schedule fit the defined time constraint, disregard the required completion date and lay out a network schedule based on the responsible functional managers' needs. A workable schedule, acceptable to the functional staff, will result; but it will not satisfy the project sponsor or management, as the required completion date will probably be missed. However, this ideal schedule will have compression potential for meeting a reasonable completion target.
This length of the ideal network schedule's Critical Path defines the minimum expected project completion time and the difference between the required and expected completion times represents the minimum amount of schedule compression needed to ensure success. Since the Critical Path contains the specific activities which cause the project to take longer than desired, schedule compression should be selectively applied to those activities, and only to the extent that a reduction in project duration results. Excessive compression will shift the Critical Path to a secondary path. Once this happens, redirect compression accordingly.
Consider the following in compressing the Critical Path:
• Selectively reduce task durations or alter precedence relationships.
• Evaluate the incremental cost and performance risk of each potential compression step, then maximize the schedule benefit for the least cost, at the lowest possible risk.
• Where possible, compress the earlier tasks. As a general rule, the early project tasks are easier and less costly to compress than the later ones. The professionals responsible for the project's initial effort can be easily motivated, once they are convinced that a realistic urgency exists. Later tasks either have greater labor requirements or employ trades or skills which command premium pay for overtime.
• Favor early compression over late compression to save the reduction potential of the final tasks for later use. as unexpected execution problems are likely to cause a schedule slip. In addition, the potential savings available in the early tasks will be lost, if not taken before the tasks are completed.
• Do not be deceived into believing that early compression may not be necessary because time may somehow be gained during project execution. Lucky breaks just don't happen. If one does occur, it will likely result from a planned effort and not from a stroke of good fortune.
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What you need to know about… Project Management Made Easy! Project management consists of more than just a large building project and can encompass small projects as well. No matter what the size of your project, you need to have some sort of project management. How you manage your project has everything to do with its outcome.