What Are Activity Duration Estimates?
Is it time to develop the project schedule? Get started by estimating how long it will take to complete each work activity. It’s the first step in accurately estimating the duration of a project.
By estimating activity durations, we improve our chances of developing a reliable project schedule. Our chances are improved because the duration estimates are made at the smallest work level; the activity level. By estimating time at the smallest level of work, project managers are more likely to account for all the work that must be completed.
When making a duration estimate, include the amount of time for completing each activity. Measure from start to finish but don’t include any lags. Here, we’re only concerned with estimating the duration of each single activity.
Duration estimates aren’t always black and white. Occasionally assumptions are made and resources are changed. Because there are variables, it’s a good idea to document how the estimates were determined. The documentation will be useful when performing risk identification.
Who Estimates the Activity Durations?
The person responsible for creating the project schedule is typically the person who estimates activity duration. For most projects, that person is the project manager.
What Are the Inputs?
To estimate activity durations, we need information regarding the project activities. We need to know what they are and how many of them there are. In addition, we need to know the resources assigned to the activities and their availabilities. Likewise, it’s most helpful to have some knowledge regarding the past performance of the assigned human resources. Knowing this, it’s not difficult to see that inputs to estimating activity durations include the schedule management plan, activity list, activity attributes, activity resource requirements, resource calendars, resource breakdown structure, risk register, enterprise environmental factors and organizational process assets.
How Are They Used?
The activity duration estimates are inputs used to develop the project schedule. The template below provides for single-point estimates only.