The Work Breakdown Structure
The Work Breakdown Structure
• The WBS: All the tasks that must be done to complete a project’s
deliverables
– Tasks are arranged in a hierarchy of broader categories of work down to specific
work tasks
Work Breakdown Structure
(WBS)
• Illustrates project scope
• Describes project subcomponents as:
– Activities (verbs) – “install new plumbing”
or
– Deliverables (noun) – “new plumbing”
Roles Played by the WBS
• Lays out the scope of project work
– All project tasks must be accounted
• Provides the foundation of all project estimates
– Times, costs, resource requirements, etc.
• Helps with the project’s organizational structure
– How tasks relate to one another, authority structure, etc.
WBS: The Compliance Project
Compliance Project
1.0 Administration
2.0 Physical Therapy
1.1 Review State
3.0 Food / Nutrition
Inspection Report
3.1 Review State
Inspection Report
1.2 Review State
Compliance Standards
3.2 Review State
Compliance Standards
1.3 Develop
Policies and
Procedures for
State
Compliance
1.4 Implement
Evaluation and
Correction
Procedures for
All Areas
1.3.1 Develop Corrective
Procedures:
1.3.2 Develop
Maintenance SOPs :
1.3.2.1 Planning
1.3.2.2 Financial
1.3.2.3 Supervision
4.0 Medical Care
3.3 Develop
Policies and
Procedures for
State
Compliance
3.3.1 Develop
Corrective Procedures
3.4 Implement
Evaluation and
Correction
Procedures for
All Areas
3.3.2.1 Planning
3.3.2 Develop
Maintenance SOPs
3.3.2.2 Preparation
3.3.2.3 Delivery
WBS Inputs
• Project scope management plan
• Project scope statement
– Identifies deliverables
– Major steps required to complete the project
• Experience with similar past projects
• Organizational process assets
– Guidelines, organizational policies, procedures
Producing a WBS: Breaking Down Project Work
• Envision a project deliverable
– List all major jobs needed to achieve the deliverable
– Break down major jobs into their smaller component tasks
– Continue until tasks can provide all the detail needed for
resource, time, cost, and risk estimates
WBS Techniques
• Decomposition participation includes:
– Project team
– Customers
– Subject matter experts
• Major project deliverables identified
• Codes assigned to each WBS component
–
–
–
–
–
Level 0 - project itself
Level 1 - major deliverables
Level 2 - individual components of each deliverable
Etc.
Final level – work package
Work Package
• Lowest level of WBS
• Should contain activities that are short in duration (1 or 2 weeks; 80 hour
rule; and no longer than a reporting period).
• Work package activities can be completed by an individual or a small
team
• All work packages should be similar in size or effort needed
• Provides input to scheduling and budget development
WBS Numbering System
Product Breakdown
• Helps
define
work
breakdown
One more product breakdown
Windsor Chair
Seat
1.1 flatten plank
1.2 layout seat
1.3 shape seat
1.4 drill seat
Legs
2.1 prep blanks
2.2 turn legs
2.3 dry fit in seat
Spreaders
Back
3.1 measure dry fit
legs
3.2 turn spreaders
3.3 drill legs to fit
spreaders
4.1 cut back slat
4.2 bead slat
4.3 steam bend
4.4 shape end tenon
4.5 drill seat to fit back
4.6 dry fit back
Spindles
5.1 cut blanks
5.2 shape blanks
5.3 drill back and
seat to fit blanks
5.4 dry fit
Producing a WBS: Core and Support Tasks
• Core tasks
– All tasks needed to produce client deliverables
• Support tasks
– All tasks needed to support project work
– Project planning, project administration
– Commonly overlooked
• They will command attention sometime
• Best to consider them in planning
Three Decomposition Approaches
• Top-Down – traditional method
• Bottom-up – used for unique projects
• Rolling Wave – greater decomposition occurs as project components
becomes more defined over time
Methods of Estimating
• Top-down method (analogous method)
– Estimates based on a similar project
• Adjusted for current situation
• Advantages
– Benefits from hindsight
– Relatively quick and easy
• Disadvantages
– Lacks precision
– Can overlook important components of current project
Methods of Estimating
• Bottom-up method
– Produce estimates for each component of each task
• Advantages
– Precision
– Estimating individual tasks often needed for project plans and project execution
• Disadvantages
– Time requirements
– Some costs are unanticipated, thus, overlooked
Leading Project Teams: The Basics of
Project Management and Team
Leadership, 2e by Anthony T. Cobb
Estimating Resources
• Human resources
– The project team
– Outside consultants, regulators, etc.
– The project leader
• Considerations
– Knowledge, skills, and abilities
– Availability: Other commitments
Estimating Resources
• Equipment and materials
– Careful consideration to special requirements
– Scheduling flow to tasks when needed is a “mission critical” task
• Other resources
– Office equipment, work space, and supplies
– Information
– Authority
Estimating Time Requirements
• Project time horizon often dictated by client
• Bottom-up time estimates still required
– Time estimates tied to each task or work cluster
• Develop best-guess, optimistic, and pessimistic estimates
• Consider lag time needs
– The need to let a job “rest”
Estimating Costs
• Include cost estimates of resource needs for all tasks
• Attend to often overlooked items
– Time value of money (inflation adjustments)
– Travel, communications, fees, overhead charges
• Adjust cost estimates for risk
Developing a Project Structure
• The work breakdown structure provides the foundation for the project’s
organizational structure
• Task arrangements through time produce project phases and its schedule
• Task arrangements from small to larger job clusters provide authority
structure
WBS Tools
• Templates
• Software
– MS Visio – displays WBS in hierarchical form
– MS Project – WBS displayed in tabular format (Gantt Chart)
Gantt Chart View
of Microsoft Project
WBS Outputs
• WBS Dictionary
– Description of each component
– Who is responsible for development
– Statement of Work (SOW)
– Important milestones
– Estimate of costs and required resources
Outcome of WBS Development
• Possible update of project scope statement and scope management plan
Scope Baseline
• Purpose: to determine and measure any deviations during project
execution
• Components of Scope Baseline
– Project scope statement
– WBS
– WBS Dictionary
Activity Definition
• Work packages broken down into discrete activities and attributes
required to produce project deliverables
• Activity Definition includes:
– Activity description
– Resource requirements
– Logical predecessor or successor activities
How Much Activity Detail Is Required?
• Can be performed by one person or a well-defined group
• Has a single, clearly identifiable deliverable
• Has a known method or technique
• Has well-defined predecessor and successor steps
• Is measurable so that the level of completion can be determined
• Has a short duration – hours or days in length
Activity Tools & Techniques
• Templates
• Documentation from similar past projects
• Rolling wave planning can be applied
Activity Output
• Activity list
• Activity attributes
–
–
–
–
–
Description
Assumptions and constraints
Leads and lags
Logical relationships
Predecessor and successor activities
• Milestones
• Requested changes to project scope statement and WBS