How to Create a RealisticProject Schedule

Dmitriy Nizhebetskiy

ACTION PLAN TO DEVELOP A PROMISE YOUWILL BE ABLE TO KEEP.

How to Create a Realistic Project Schedule

Creating a realistic project schedule is dif cult. It is a complex document with

dozens of variables. There is always some amount of uncertainty. Stakeholders

try to squeeze as much as possible into unrealistic deadlines. On top of that, you

need to make a commitment – a promise to the stakeholders to deliver the project

in time.

There is a way to ful l the task with a high level of certainty. The solution is to

approach the project schedule planning in a systematic, integrated and iterative

way.

What does that mean?

Right now I will guide you through the process and explain the basics of a realisticproject schedule.

So, here is the deal.

No matter what you do as a project manager, you plan before you act. Therefore,

you should start with the Schedule Management Plan

Ensure Your Success with Schedule ManagementPlanProject Schedule is often confused with Schedule Management Plan. The

schedule is only a part of the plan. Though, it is one of the most important pieces.

Key stakeholders will be interested mostly in a project timeline. Only because it

answers their primary question: “When will I get the results?”

However, it is a long way before you can start working on the project schedule.

What is a real story?

Project Management Basics

How to Create a Realistic Project Schedule

Before dragging coloured bars on a Gantt Chart there are a lot of questions you

need to answer.

1. What are the existing policies and processes? Your project will function in the

environment of your organisation. You will have to get approvals, negotiate to

prove the necessity of resources, and provide reports. Your project schedule

should be aligned and integrated with these processes. Otherwise, expect extra

work on your side.

2. De ne a schedule model. It is a complicated concept described in a chart

below.

A scheduling tool is used to describe a Scheduling Method. Combined with

project information it generates a Schedule Model. A version of the schedule

model with final project information output the project schedule.

Why does it matter?

In simple words, it boils down to this.

Project Management Basics

How to Create a Realistic Project Schedule

You must take into account available software and general approach to

scheduling consistent with your environment. Including other project

management processes.

For the sake of this guide, I will assume that you will choose Critical Path Method

as a scheduling method.

3. De ne Units of Measurement. Should the estimates be in hours or days?

What will be depicted on Gantt Chart? Is it calendar days, working hours, or

effective hours. Should you track both efforts and duration for a task?

Answering these questions will help you to make information consistent

throughout different processes.

4. Identify variance thresholds. You don’t want to micromanage your team and

continually update your schedule. You need to de ne whether a delay of one, two

or three days warrants a corrective action.

5. Identify reporting format. What information will go from your scheduling

model into the regular reports to the stakeholders? You need to come up with an

effortless approach.

6. Think through change management process. How hard is it to make a change

to the schedule? How to make it effortless and integrated?

That is not all…

Then comes the major integration part.

Integrate WBS with Project ScheduleThe core of project integration is a Work Breakdown Structure.

Project Management Basics

How to Create a Realistic Project Schedule

Do you remember the long path you need to cover before you start creating a

project schedule?

First, you create a Project Charter and Stakeholder Register, then Project Scope

Statement and Work Breakdown Structure.

If by this moment you have a high-quality WBS, it automatically means that you

have a framework for integration with other project management processes.

For example, in the next step, you will decompose the Work Packages into

Activities. So, if you do integration properly, each activity already has a lot of

related properties and information like:

1. Links to requirements and project objectives

2. Related stakeholders

3. Parent work package

4. Assumptions

5. Constraints

That will be helpful in future for monitoring and controlling processes.

Use Activities For AccuracyIn project schedule, we work with activities.

Why?

They provide an appropriate level of detail. They can show interdependencies

between work packages and deliverables. Activities can be done by one person

without interruption.

Also, activity is a data storage that has enough information to be used in different

processes. You will update this information several times.

Project Management Basics

How to Create a Realistic Project Schedule

Your ultimate goal is to preserve the connection to the related WBS Elements.

In future, you will use activities to perform, monitor and control project work. The

sum of related activities will give you a completed work package. In its turn,

related work packages will make you a deliverable. In the long run, you will get

back to the WBS to prove that you have created the requested deliverable.

Integration of WBS elements and activities.

Who do You Need to Get Things Done?So, once you have an activity and you know what should be done, identify what

kind of human resource you need.

In case you have a prede ned team, you usually just assign activities to existing

team members.

However, there is a catch.

Project Management Basics

How to Create a Realistic Project Schedule

If you skip the analysis of required resources, you may end up with a team not

fully fit for the task at hand.

With a prede ned team, everyone will assume that you have everyone you need.However, how could the assessment be done accurately without knowing the actualscope of work?

Don’t fall into this trap. Always analyse the scope of work with the team and

ensure you really have every speciality accounted.

Use Bottom-Up Estimate for Accurate DurationKnowing the competency and level of a resource, now you can estimate duration

for an activity. To assess the duration of a work package you estimate the

activities and sum them up. To evaluate a Delivery – you work with child work

packages.

It is a preferred way for estimation. Using a bottom-up approach gives a higher

level of accuracy. However, in case of duration, do not forget to take into account

dependencies and sequence of activities.

We have discussed how to produce estimates in details already. Refer to the relatedpost: How to Make Project Estimates.

Keep in mind that there are effort-driven activities. Duration of such activities

depends on a number of resources you can actually apply. In other words, you

can put several resources to do the job. And it will be faster.

For example digging a trench. For one person in may take ten days. But you can

apply ten persons to dig. Most probably they will not nish the task in one day.

But it will be close to it. It is an effort-driven activity.

Project Management Basics

How to Create a Realistic Project Schedule

On the other hand, if you build concrete structures. It will take that much time for

concrete to dry and fix no matter how many people will be around.

Dependencies in Project ScheduleThere are practically four types of dependencies between activities:

Finish-Start. An activity must nish before the successor can start. It is the most

common type of relationship.

I say, always use only this one unless a nature of related activities requires somethingelse.

Start-Start. An activity must start before successor can start. For example, you

must start delivering bricks before you start to build a wall.

Finish-Finish. An activity must nish before successor can nish. For example,

you can’t finish repairs until you fully clean up the area.

Start-Finish. An activity must start before successor can nish. Well, before you

start thinking about a good example, forget about it. This type is rarely used.

Examples are way too confusing.

Project Management Basics

How to Create a Realistic Project Schedule

FS, SS, FF type of dependencies.

Also, there are several types of dependencies by nature:

Mandatory dependency or Hard Logic. A dependency dictated by the

nature of the work or is required by the contract.

Discretionary Dependency or Preferred or Soft Logic. A dependency you

or your organisation chose. There are different ways to do one and the same

work. But for some reasons, it is the way you always do similar things. In

general, it is dictated by convenience or efficiency of work.

External Dependency. Dependency imposed by people or an organisation

outside of your project.

Internal Dependency. The dependency that is based on the needs of a

project. In other words, it is something you can control.

All you need to do is to analyse all activities and identify a predecessor for each

one.

Project Management Basics

How to Create a Realistic Project Schedule

Even if activities are unrelated, you would want to build a logical sequence of work.So use Discretionary Finish-to-Start dependencies for such activities.

Network diagramNetwork diagram shows dependencies between activities. Usually, a Precedence

Diagramming Method is used. In this method, boxes are used to represent

activities and arrows show dependencies between them.

But do you need to create a diagram separately? If your software does not do this

automatically, it will take a lot of efforts. Therefore, I don’t think it is worth it.

Anyway, you will use some tool to visualise your schedule. In most cases, you will

be able to perform analysis as if it is a network diagram.

Nevertheless, Network Diagram is a very powerful tool, and we will discuss it in a

separate post later.

A network diagram created in OmniPlan

Project Management Basics

How to Create a Realistic Project Schedule

Use Your Float WiselyFloat or Slack is the amount of time you can delay an activity without delaying an

intermediate deliverable or project end date. It is a Total Float.

The oat is your management resource. Even if you do not create a Network

Diagram and do not calculate forward and backwards passes, it is useful to know

the float.

How can you actually use this?

For example, you know that a task will take two days. However, it is not on the

critical path. It has several days of oat. It is a good chance to utilise your

inexperienced or ineffective resources. They will do the work. But you will not

jeopardise the schedule if it will take more time for them.

Define Critical PathYou can always sequence all your activities one after another. That is not

ef cient, though. Most probably you can perform several activities

simultaneously. Therefore, you will have parallel paths from project start to

finish.

Critical Path is the longest duration path through a network diagram. It also

means that it is the shortest time it could take to complete a project. Moreover,

it’s worth knowing that activities on a Critical Path have zero oats. Therefore,

there is no way you can delay them.

Why do you need a Critical Path?

Project Management Basics

How to Create a Realistic Project Schedule

1. It determines duration of the project

2. It shows you where to focus your attention. All activities on Critical Path

impose risks.

3. If a problems arise with activity on a critical path – it requires your

immediate attention.

4. Shows you the ways to adjust project schedule.

Apply Resources CalendarFor now, we operated with absolute values of duration. It never coincides with

calendar duration. There are holidays, vacations, sick leaves, and unexpected

delays.

Resources Calendar, in essence, is just a calendar that shows when resources are

available.

And there is a whole set of problems here. It is really hard to produce an accurate

Resources Calendar.

What’s the real story?

If you have a prede ned team – it lessens the troubles. You just need to manage

vacations and plan for them. Also, you need to consider risks of sick leaves.

If you do not have a team and you, need to acquire it. Well, it is more complicated.

You need to plan the dates when you will get a resource. You may need to nd

and hire a person rst. You may need to wait when a person is released from

another project. You may need to train him before he can add value to your

project.

On the other hand, there may be constraints on the resources availability. It may

be available part-time. Or his contract ends soon.

Project Management Basics

How to Create a Realistic Project Schedule

You need to take all of this into consideration. And we are talking not only about

human resources. You may need access to equipment and materials. It is a

separate plan on its own.

To use it ef ciently, I suggest thinking of it this way. Each resource has time slots

that you can fill in with your activities. Not vice versa.

In any case, keep in mind that you may need to make a lot of assumptions on

resources availability. You need to be proactive to secure the resources you were

promised. And of course, you need to take resources calendar into consideration

during risk management.

Do a Reality CheckNow you have an end date of your project. Is it before the deadline? If it is – that’s

good. If not, you need to develop options how to nish a project with minimal

trade-offs.

Analyse the gap between the deadline and the estimated end date of the project.

You need to identify what is the best way to fit the project within constraints.

Keep in mind that project plan should be exible. If your end date and the

deadline are too close, that is also bad. It is risky. Be sure to consider Essential

Project Planning Concepts.

Adjust Project ScheduleIf you need to compress the project schedule to meet the deadline, there are not

many options.

You can either reduce the scope.You can increase the costs to apply more resources.

You can move the deadline.

Project Management Basics

How to Create a Realistic Project Schedule

Of course, the combination of these options is also valid. But it is always about

scope, time, and costs.

Crashing is a project schedule compression technique. You simply add more

resources to finish the project on schedule.

You trade time for money. It is a less risky approach. It increases the costs and

communication overhead. However, it is not always applicable.

And keep in mind that buying a better tool or machinery may also be an example

of crashing.

On the other hand, you can try to perform activities on the Critical Path in

parallel. If it is possible at all. This technique is called Fast Tracking.

In reality, it means that you will try to start an activity while it predecessor is not

yet finished.

But here is the deal:

Usually, it causes rework and introduces a lot of risks. You would need to

communicate a lot even if you planned these activities thoroughly. Be ready that

there will be a lot of con icts and defects. You will have to manage them closely

to keep the work running.

Also, Fast Tracking introduces long-term drawbacks. Quite often it includes violationof processes and making shortcuts. This way or another you will end up withtechnical, quality or documentation debt. After extended periods of fast tracking besure to find time and efforts to catch up.

Project Management Basics

How to Create a Realistic Project Schedule

Iterate After Risk ManagementThere was one thing that confused me a lot. Project Schedule is the input to the

Risk Management processes. However, you address risks and develop risk

response plans much later, closer to the end of the planning.

So, at this moment, you develop a draft of a schedule. There may be many drafts

of the project schedule. Planning is an iterative process. Once you nd out more

details about the project, you need to get back and validate all previous results.

You can nalise the schedule only when you performed risk management

activities, adjusted the project management plan, finalised the budget and scope.

Know What You Need to Produce?Project Schedule shows start date, the end date, duration, and dependencies of

each activity.

Gantt charts, milestone charts, network diagrams are just visualisations.

Each of them has its own use.

Gantt Chart is useful for tracking progress and reporting it to the team.

Milestone Chart is for reporting to senior management.

Network Diagrams show interdependencies between activities.

Choose appropriate representation of the project schedule to your purpose.

Project Management Basics

How to Create a Realistic Project Schedule

Put Stakeholders on Your TeamAs a part of a project management plan, project schedule should also be

approved and baselined.

To reduce the stress and risks at the end, collaborate with key stakeholders early

on. It is a good practice to get feedback on rst drafts of the schedule. They might

help you to find weak spots and identify more risks.

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