Best Practices Checklist: Establishing the Duration of All Activities
Activity durations are directly related to the assigned resources and estimated work required.
In general, estimated detailed activity durations are shorter than the reporting period management requires.
Durations are as short as possible, to a point, to facilitate the objective measurement of accomplished effort.
Long durations should be broken into shorter activities if logical breaks can be identified in the work being performed. If it is not practical to divide the work into smaller activities or insert intermediate milestones, justification for long durations is provided in the schedule basis document.
Very short durations, such as 1 day or less, may imply a schedule that is too detailed and require more-frequent updates to schedule duration and logic than is otherwise necessary.
LOE activities are clearly marked in the schedule and derive their durations from other discrete activities.
All activity durations within the schedule are defined by the same time unit (hours, days, weeks). Days are preferred.
Planning packages representing summarized or less-defined future work should be integrated into network logic.
Activity durations are estimated under most likely conditions, not optimal or “success-oriented” conditions. “Most likely” for estimated durations implies that duration estimates do not contain padding or margin for risk. They should also not be unrealistically short or arbitrarily reduced by management to meet a program challenge.
All assumptions related to activity duration estimates are documented in appropriate detail, such as describing the methodology used to create the estimate (for example, parametric analysis of historical data or opinion of a subject matter expert) and all specifying supporting historical or analogous data.
Activity duration estimates for a WBS element in a schedule should clearly map to and correspond with the basis of the cost estimate for the same WBS element.
Calendars are used to specify valid working times for activities and, when feasible, resources.