Usually the process of estimating the time required for a project begins with a simple to-do list. Everything that needs to be completed is broken down into individual tasks. To the untrained eye the project manager can now make an educated guess on the time it will take to complete the project and employees can begin working through the task list. In reality efficient project management and time estimation is and should be a little more complicated. What should a project manager consider when estimating the time required for tasks within a project?

The to-do list is a perfect place to start and is vital when estimating the time. All tasks within the project should be listed. Remember that the client themselves may need to complete some tasks for the project which should also be set as tasks and included in the time estimate. Obviously the time they take to complete their part will not be charged for, but if your project depends on these tasks being completed as part of the process then it will affect the deadlines if they are not done when requested. An example would be the client testing the product once it has been delivered. This is a task that may take several days or weeks and the company cannot begin to complete the required alterations and finishing touches until this has been done.

Once all the tasks have been listed, get experienced people to estimate the time required for each task. Never assume that you know better than the experts. Time estimated need to be based on a foundation of knowledge and experience. It is a good idea to create a spread sheet with each task listed on it. Each person involved in the project can estimate the time for the tasks they will be completing. When quoting a price for a project to a client it will then be possible to give them a complete breakdown of the costing involved thus justifying your position.

Examine carefully how many staff are working on the tasks within the project. There may be three programmers in a software house and all of them will be working on the project. This may mean that tasks will not need to run consecutively since the programmers can be working on different parts of the project at the same time. The amount of days estimated to complete the project will not differ due to this fact. If each programmer spends a total of ten days to complete the project then thirty days total will be charged to the client. If each programmer is working at the same time on different parts for ten days then the total number of days to charge will still be thirty. It will mean however that the initial version of the product can be delivered after ten days. Whether or not tasks can be worked on in parallel to each other should be a major consideration in your time estimate.

As well as parallel tasks, it is important to consider whether any tasks are dependent on other tasks being completed. As a simple example, if you were making a cup of coffee, one task would be switching on the kettle and another task would be pouring out the boiling water. The second task is dependent on the first task being completed. When estimating time required for tasks this should be examined carefully. It may cause hold ups and wasted time further in the project if people are waiting for other people to complete work. For a project to run smoothly, everyone must be aware of what they need to do and in what order.

Always consider when estimating time that an employee may not be able to begin working immediately on the project. They may have other commitments and may never be able to work on a project full time if they are working on several projects at once. In order to accurately estimate the timeframes it is worth checking the staff commitments including any holiday time which will need to be taken into account. Even if a project will take thirty days to complete and this is the time charged to the client, bear in mind than in reality this time could be spread over sixty days due to multiple commitments. Since some tasks will be completed by the client such as testing, estimated time for delivery must be realistic. Sometimes extra things come up unexpectedly that nobody could plan for. Things go wrong or sometimes things take longer due to unforeseen circumstances. When estimating the time it is a good idea to add some extra days for a buffer so the client is not disappointed. In this way the project can be delivered on time or early rather than late.

Remember how important it is to estimate time for the User Acceptance Testing. This should come from both sides. The internal testing should be done first and then the client should be given the chance to complete their own set of testing. Once the testing has been completed it may be necessary to make further changes to the product in order to fix any issues that arose during the testing stage. A suitable amount of time should be estimated to complete this. Once all changes have been made a second set of testing should be completed to ensure the changes have worked correctly. Once an employee becomes more experienced it will be easier for them to estimate time based on previous experience. In the meantime consider what parts of the product may need adjustment or complete alteration and base the time on how long it would take you to complete these changes.

Do not forget your own project management tasks such as creating an initial project document agreeing the scope of the project and completion criteria. Just as you need to create it, your client will need time to read and agree it. These should be set as two separate tasks. The scope document is vital to a project. Throughout a project, many clients will come back with changes, further additions and the wish list can get dangerously large. If you have not agreed the scope in advance then it will be more difficult to charge since the client can claim you were too vague initially or that they asked for the additions to begin with. This can drastically alter the time required to complete a project. You should therefore estimate time to create documents such as the scope document and end of project report.