The concept of Schedule Padding means adding more time / value to the estimate, a sort of “pad” (hence the term Padding) that can soften the “fall” in case of unexpected or errors of evaluation.

The estimation techniques, such as the analogy or bottom-up estimations, can provide more or less reliable estimates, but all have the same problem: they depend on the capabilities of those who formulate them. It is never certain that these are correct and there is always the doubt that they may be mistaken for excess or defect, despite all the good will in formulating them. The estimates represent one of the most critical and complex areas for a project manager. It is not possible to reduce the effort to 15 hours if two people work on the project, but it is possible to reduce the overall completion time. The total effort is always 30 hours, no matter if there are one, two or more people working on the project. However, if the friend could work only 2 hours a day, the duration would extend to 6 days because the resources would only work for a total of 5 hours a day. The duration in this case would therefore be 5 days (30 hours of total effort divided by 6 hours / day). The duration is usually expressed as working days or working weeks and depends on the availability and capacity of the resources.įor example, if you spend 3 hours a day working on the fence, the total duration would be 10 days (30 hours of total effort divided by 3 hours / day).īut if, for example, a friend helps every day, then you would have two resources working for 3 hours a day on the fence = 6 hours a day.

Estimate activity durations