Aspiring #projectmanagers must learn how to perform a variety of tasks in order to get a project started and estimating activity duration is one of them. It’s not always an easy task to estimate the project duration, because doing so needs a Project Manager’s knowledge of some theory, along with the application of some best practices and methodologies.
To estimate activity duration is a lengthy process and it takes time for a long-term project. Ideally, you should involve your core project team in estimating the duration. You should involve the project team, who will work on the project to achieve the project objectives, project management team, and all the identified key stakeholders to make a consensus on the milestone dates, and delivery schedules. Depending on this duration, you can develop a schedule, with milestones for your project.
Estimating activity duration can be for a project phase or product phase and is iterative in nature. It can be changed as work progresses and as new activities identified in your project. Initially, you can estimate your project based on the network diagram (sequencing the activities). It can be further modified based on the changes done in the project during the execution, controlling and monitoring the process.
The PMI® recommends a few project management tools, methodologies, best practices for estimating the duration. We described those in the post here: estimation techniques.
The Estimate Activity Durations is the process of evaluating the number of work periods required to deliver project activities with given resources. Once activity resources are determined, these resources evaluate the duration of the activity. Based on their estimations, the total project duration will be calculated respectively.
Before estimation, if there are ambiguities or unclear points about an activity, the estimation will have #padding.
#Pad is a buffer time or buffer cost added to an estimate because of the uncertainty or insufficient information about the activity. If there is a low level of details about the activity, or information is vague and not concrete, or if there are risks that may arise and cause the activity to take longer - estimator adds padding to an estimate to cover the challenges and uncertainty.
Therefore the project manager works on finding ways to reduce the uncertainty level and project variability. Read here about the Cone of Uncertainty: link.
Avoid large paddings by doing the estimation after narrowing the Cone of Uncertainty and gathering a more detailed scope. Try Estimatess.io for free