Role

Building a Schedule from Scratch

1

Project Manager

Review the Project Charter draft to ensure you understand the deliverables to produce, the overall timeframe, risks and assumptions, etc. The Project Charter may not be complete, but it needs to be in decent first draft form so that the draft schedule can be built. The Project Charter and any other relevant documents should be reviewed before you start to build the WBS

2

Project Manager

Create first level of a Work Breakdown Structure

The purpose of the Work Breakdown Structure is to capture all the elements of work. First determine the large chunks of work that must be completed for the entire project to be completed. At this point, it does not matter how you define the large chunks of work. It is only important that all the work is identified at the end of the process. For instance, a traditional breakdown might be 'planning / analysis / design / construct / test / implement', which lays out the project in a high-level timeline. The breakdown could also be by deliverable - for instance 'online application / data warehouse / data marts / user query tools'. It could also be by some functional breakout such as 'extract data / load data / report on information'. You can break down the work into whatever structure makes sense for your project.

Sequencing is not important at this time.

It is important to identify an estimating threshold so that you know how small to break the work down. See 2.1.2 Build the Schedule and Budget / Estimating Threshold for more information. This process of breaking larger work components into smaller work components is called “decomposition”.

When the Work Breakdown Structure is complete you have an inverted (upside-down) tree structure of activities.

The high-level project itself is referred to as level 0 and the first high-level breakdown of work is called level 1.

3

Project Manager

Estimate the work effort for work components at this level

After you finish your initial work breakdown, estimate the effort required to complete each individual work component. There are a number of techniques you can use for estimating the effort. (See 2.1.1 Estimating Process and 2.2.1 Estimating Techniques for more information on estimating.)

Once you have the estimate for each work component, check each component to see if it meets the following two criteria.

• Is the effort required to complete the work component less than your estimating threshold? (See 2.1.2 Build the Schedule and Budget / Estimating Threshold for more information.)

• Do you (or someone on your team) understand the detailed work required to complete this work component? The detailed work components on the WBS will ultimately be moved to the schedule. You don’t want to have activities on your schedule that no one on your team fully understands.  

If you understand the detailed work required to complete the component and if the estimated level of effort is smaller than the estimating threshold you do not need to break the component down further.

Work components that are estimated to require more effort than the estimating threshold, or work components that you do not fully understand should be broken down further If you have a medium to large project, most of the work components at the first level will still be larger than the estimating threshold and will need further decomposition. 

4

Project Manager

Determine if work needs to be broken down further

Review each remaining work component to determine the set of lower-level activities that are required to complete them (you can also break down work components that are already less than the estimating threshold, but you do not need to). This gets you to level 2 of the Work Breakdown Structure.

When this second level of work components is completed, again estimate whether the work effort of the second-level activities are greater than the estimating threshold, and validate whether you understand the actual work that needs to be done to complete this work component. If the work effort is greater than the estimating threshold, or if you do not understand the work, the specific components need to be broken down further. Work components that you understand and are already less than the estimating threshold can be left as they are.

This process of breaking the work components into a lower level set of activities (steps 3-4 above) should continue until all of the work components are represented as granularly as necessary to ensure that no activities have estimated effort larger than the estimating threshold, and that you understand the work. This takes you to levels 3, 4, 5 etc. Rarely would you need to break the work down greater than five levels.   

There is one exception to this process. If your project is large, it is likely that you may not know enough to be able to break all of the work down to this discreet level. If you cannot break the work down into small enough components you may still be okay as long as those higher-level components do not need to be worked on any time soon. In that case, you can leave the work components at the higher level until you get closer to execution (three months), at which time you will know enough to be able to break the work down at a more granular level.

Since you have not sequenced the work yet, you may not know whether the work needs to be done sooner or later. Nevertheless, if you do not know enough to break down the work lower that the estimating threshold, leave it at that level until the work is sequenced later. At that point you will know if you have a problem. If the work needs to be done relatively soon, you will need to figure out how to break the larger components into a lower level of detail so that you can assign the work to a team member. If the work ends up being executed in the more distant future, the components can be left at the higher level for now.

5

Project Manager

Estimate the work effort for all detailed activities

When the Work Breakdown Structure is complete you have an inverted (upside-down) tree structure of activities. You have already done a high-level estimate of effort to determine if the work for each activity is greater than the estimating threshold. When the Work Breakdown Structure is complete, you need to review all the detailed activities and assign initial estimates of effort hours to all of them (the detailed activities are the ones at the lowest level that are not broken down further). You can use estimating techniques found in 2.1.1 Estimating Process and 2.2.1 Estimating Techniques. For instance, you may determine, by expert opinion, that a certain activity is 70 effort hours. Then you can use an analogy technique to determine that other activities that are about the same size will also take 70 hours to complete.

For additional tips and techniques for building a Work Breakdown Structure, see 2.1.5 Work Breakdown Structure.

When the Work Breakdown Structure is complete, you might also want to create a series of cost accounts to help allocate and manage the project budget. See 2.1.6 Cost Accounts for more information.

6

Project Manager

Create a Network Diagram by sequencing the detailed work components at a high-level

Activities that are further broken down into smaller activities are called summary activities, since they represent a summary of the more detailed work components under them.

The first step in converting the Work Breakdown Structure into a network diagram is to look at all the detail activities (not the summary activities) and sequence them in chronological order. Remember to include all the activities that are not broken down further, regardless of what level they are at in the WBS. In the sequencing process, you determine the work that gets done first, second, third, etc. This step is the reason why it does not matter how you structure the initial WBS. As long as you discover all of the work in the WBS, the sequencing of the activities is done now.

7

Project Manager

Determine the critical path of the project

Once you have completed sequencing the activities, your schedule will have many paths of dependent activities that go from the beginning to the end of the project. There is one path that is more important than any other path – the critical path. This is the one path that is driving the project end date. When you have finished sequencing the activities you need to understand the critical path of the project. See 2.1.7 Critical Path for more information on this very important concept.

8

Project Manager

Review the work sequence a second time for detailed work relationships

When you have a rough sequence established, go through the work again. At this time look for all the relationships and dependencies between the activities. You should note whether one activity cannot start until another activity is finished. In many cases, two or more activities may need to be completed before another one can start. You must identify the work that must be done sequentially and the work that can be done in parallel with other work. This step is very important and is the key to having a solid schedule to start the project. More information on establishing the activity sequence is available at 2.1.3 Precedence Relationships

9

Project Manager

Look for date constraints

Next you should enter any date constraints. Date constraints are events that are outside of the control of the project team and must be managed around. They are not necessarily problems or risks, but they need to be taken into account for the purposes of your schedule. Many constraints have date implications, but not all do. For instance, a deliverable may need to be completed before the Board of Directors meeting on a certain date; or, you may need to place an order with a vendor by a certain date.

10

Project Manager

Assign Resources

So far you have built the plan without specifying any resources. In this step, you assign resources to the work activities. If you have specific resources allocated to your project, you can assign them directly to the appropriate activities. If you do not have all your resources assigned, this resource assignment will need to be by a generic type of resource. For instance, if you have three 'programmers' assigned, you may need to assign them to the schedule as 'programmer1', 'programmer2' and 'programmer3'.

11

Project Manager

Create the initial project schedule

If you are using a tool to do the initial scheduling of the project, go ahead and create an initial schedule now. Based on the effort hours, resources and constraints, the tool will calculate the overall timeline of the project from beginning to end.

12

Project Manager

“Level” the resources

In the prior steps you assigned resources based strictly on which resources could do the work. What you may find is that a resource may be allocated for too many hours one week and not enough hours the next week. In this step you check to see if resources are over-allocated or under-allocated (if you have a large project and are not using a tool, this might be impossible). Smoothing out this workload is called resource leveling. Techniques for leveling resources include:

• Scheduling activities sequentially, even though they could be done in parallel if not for resources constraints. For instance, you may have two activities, each estimated at 40 hours, that can be worked on at the same time. However, the same resource is needed to work on both. In this case, one activity needs to be scheduled first and the other activity needs to be done afterward.

• Move work from one person who is over-allocated to another person with similar skills that is under-allocated in the same timeframe.

• Look for slack elsewhere in the schedule and push some work there. For instance, an activity may have 5 days duration, but can be completed within a 30-day window. A resource may need to work on many other activities first, but have some available time toward the end of the 30 days. In this case, the more flexible activity can be scheduled later, after other less flexible activities have completed first.

• Change the resource mix. If two (or more) people are assigned to an activity, see if one person can be freed up to work on another activity that is resource- constrained, even if the first activity now takes longer to complete. Likewise, see if additional resources that are under-allocated can be added to an activity to accelerate its completion and then allow another activity to be started earlier. 

After the initial schedule is run, Joe is over-allocated on days 8 and 9. After resource leveling, some of the work is moved to day 10, and the rest of the work is moved to day 11. The activity now extends into an extra day of duration, but does not over-allocate Joe.

13

Project Manager

Adjust plan

After you have estimated the effort for each activity and assigned resources, you can again schedule the project and see how long it will take (duration). At this point you have your first real draft of a schedule.

14

Project Manager

Estimate the cost of the project

Now that you have assigned resources, you have the information necessary to complete the initial budget estimate. External labor can be estimated based on the resources (or types of resources) that you assigned previously. If you have assigned a cost per hour to your internal resources, you can also see the total project resource costs – at least in terms of labor. You can then add non-labor expenses, including travel, training, hardware, software, supplies, etc. You may have known many of the non-labor costs earlier, but you can consolidate all of the labor and non-labor costs now.

15

Project Manager

Review the schedule to see if it makes sense

You need to feel comfortable to defend your estimates to your manager and sponsor. If you feel that the schedule doesn’t reflect what you need, make changes and reschedule. For instance, your schedule may show duration of ten months, but you may only have eight months to get it done. At this point, you can look at alternatives such as adding resources, working some overtime, removing some of the work activities, etc.

You might also feel that the schedule is not right, given other experiences that you might have.

TenStep recommends that you prepare a schedule estimate that is within 10% before you start the project. 

The bottom line is that when you provide the estimate for the schedule, others may question your numbers. If you don’t feel comfortable enough to back them up, you have more work to do, In other words if you cannot defend your numbers, you should spend more time trying to create an estimate that you feel confident in.

16

Project Manager

Establish milestones and gate reviews

Determine when key deliverables will be completed and assign milestones to those events. A milestone is an activity with zero duration that is used to help manage the work at a high level. If you (or your manager) run a report showing the project milestones, you should be able to quickly tell whether you are on schedule, ahead of schedule or behind schedule.

You can plan major milestones at the end of project phases. This technique is called a “phase gate review”. You can see more details at 2.1.10 Establish Phase Gate Reviews.

17

Project Manager

Save a current copy of the schedule as a baseline

Once the schedule is completed and the project is approved, save a current copy of the schedule as a baseline version. Later on when the schedule is managed, the updated schedule can be compared against this original baseline version to determine variances.

18

Project Manager

Create Schedule Management Plan

 This document defines and communicates how the schedule will be maintained throughout the project. It is part of the Project Management Plan. See 2.1.8 Create Schedule Management Plan for more details.

19

Project Manager

Review the budget to see if it makes sense

You need to feel comfortable to defend your estimates to your manager and sponsor. If you feel that the budget doesn’t reflect what you need, make the necessary changes. 

TenStep recommends that you prepare a budget estimate that is within 10% before you start the project. 

The bottom line is that when you provide the estimate for your budget, others may question your numbers. If you don’t feel comfortable enough to back them up, you have more work to do, In other words if you cannot defend your numbers, you should spend more time trying to create an estimate that you feel confident in.

20

Project Manager

Finalize and allocate budget

Now that the schedule is finalized and you have estimated the total cost of the project, you can establish your project budget. On some projects this may be one budget at the aggregate level. On larger projects, you may establish cost accounts for each work package or for a group of work packages.

21

Project Manager

Create Cost Management Plan

This document defines and communicates how the budget will be maintained throughout the project. It is part of the Project Management Plan. See 2.1.9 Create Cost Management Plan for more details.