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SCHEDULE DELAY ANALYSISSCHEDULE DELAY ANALYSIS

NielsenNielsen--Wurster Asia PacificWurster Asia PacificFebruary 2004February 2004

Nielsen-Wurster Asia Pacific

Introduction

� Components of a Schedule DelayAnalysis

� Types of Schedule Delay Analyses� CPM Scheduling Basics� Window Analysis - Steps� Window Analysis - Presentation� Causation Analysis� Responsibility Analysis


Schedule Delay Analysis

� Components• Quantification

- Windows

• Causation- Issues that Caused Impact to Project Execution

• Responsibility- Determination of Parties Responsible

• Damages- Allows for the Quantification of Damages, typically

Extended Site Office Overhead and UnabsorbedHome Office Overhead


Schedule Delay Analysis – Types

�As-Planned versus As-Built�As-Planned Impacted Analysis�Collapsed As-Built Analysis�Period Analysis (As-Built Critical Path)�Window Analysis


Window Analysis

� Nielsen-Wurster’s Chosen Methodology isWindow Analysis – Why?• Developed In-House• Contemporaneous• Applies No Hindsight• Critical Path Driven• Uses Schedules As-Is• Objective – only Uses Facts• Avoids Manipulation• Dynamic – Consistent with CPM Scheduling


CPM Scheduling Basics

� Method of Scheduling that calculates the timeduration required to complete a Project or set ofTasks based upon three major components:• Number of Activities or Tasks• Estimated Activity Duration• Logical Relationships

- Mandatory versus Discretionary


CPM Scheduling Basics

�Scheduling Software takes the threeinputs and calculates the scheduleproducing:• End Date of Project

• Critical Path of the Project (end dateconstrained versus not constrained)

• Float


Window Analysis Methodology

� Eight steps:1. Project familiarisation2. Initial and revised schedule reasonableness3. Identify critical paths4. Determine window time periods5. Confirm actual dates for critical activities6. Perform delay calculations for each window7. Tally calculated delay for all windows8. Validate results [iterative process]


Window Analysis – Step 1

�Familiarity with the Project• Read the Complaint

• Read the Contract• Know the Delivery Mechanism

• Interview Key Personnel• Review Key Documents

�This knowledge will increase accuracy ofAnalysis



�Analyse Schedules for Reasonableness• Number of Activities• Number of Relationships• Activity Sequencing• Timing of Events• Use of Constraints• Resource Loading• Claim Digger

�Key – Does it Make Sense?



�Determine Critical Paths of Baselineand Updated Schedules• Critical Path is the Longest Path through

the Network- Typically zero float in non-constrained end date

schedule- Can be negative float path in constrained end

date schedule



�Determine Window Time Periods• Major Shifts in Critical Path• Significant Events / Issues

• Significant Change in Float• Schedule Revision versus Update

�Key – NOT EVERY UPDATE• Typically 4 to 10 Windows


Sheet 2 of 7

ActivityID

ActivityDescription

Meg Foley - Purchasing Manager

BA450 Assemble Brick Samples

AS201 Review Bids for Temp Control Equ

BA480 Assemble and Submit Flooring Sa

AS202 Award Contract for Temp Control

BA411 Prepare and Solicit Bids for Heat P

BA421 Prepare and Solicit Bids for Brick

AS213 Prepare and Solicit Bids for Syste

BA412 Review Bids for Heat Pump

BA407 Prepare and Solicit Bids for Floori

BA422 Review Bids for Brick

BA413 Award Contract for Heat Pump

BA550 Fabricate and Deliver Heat Pump

AS214 Review Bids for System Controlle

BA423 Award Contract for Brick

BA600 Deliver Brick

BA408 Review Bids for Flooring

AS215 Award Contract for System Contro

BA409 Award Contract for Flooring

BA620 Fabricate and Deliver Flooring

CS400 Prepare and Solicit Bids for Conve

CS410 Review Bids for Conveyors

CS420 Award Contract

CS450 Fabricate and Deliver Conveyors

Vendor

AS206 Fabricate & Deliver Temp Control

1999 2000SEP OCT NOV DEC JAN FEB MAR APR MAY JUN

Assemble Brick Samples

Review Bids for Temp Control Equipment

Assemble and Submit Flooring Samples

Award Contract for Temp Control Equipment

Prepare and Solicit Bids for Heat Pump

Prepare and Solicit Bids for Brick Exterior

Prepare and Solicit Bids for System Controller

Review Bids for Heat Pump

Prepare and Solicit Bids for Flooring

Review Bids for Brick

Award Contract for Heat Pump

Fabricate and Deliver Heat Pump and Con

Review Bids for System Controller

Award Contract for Brick

Deliver Brick

Review Bids for Flooring

Award Contract for System Controller

Award Contract for Flooring

Fabricate and Deliver Flooring

Prepare and Solicit Bids for Conveyors

Review Bids for Conveyors

Award Contract

Fabricate and Deliver Conveyors

Fabricate & Deliver Temp Control Equipment

Sheet 2 of 7

Data Date

Revisionissued here(Change incritical path)

Window Timeframe



�Confirm Actual Dates

WindowAnalysis+ =

Garbage In Garbage Out



�Calculation of Discrete Delay / Gain• Every Critical Activity in Every Window

�Start Gain�Start Delay

�Production Gain�Production Delay

LOGICDEPENDENT

DURATIONDEPENDENT


Start Gain

�Start Gain- Dependent upon it’s predecessor

This period of timeis gain to the

project


Start Delay

�Start Delay- Dependent upon the logic of it’s

predecessor

This period of timeis delay to the

project


Production Delay/Gain

�The difference in the actual activity’sduration versus planned

- Not dependent upon logic

�Delay:

�Gain

This period of timeis delay to the

project

This period of timeis gain to the

project


Delay and Concurrency

� Rules• There can only be one unit (day) of delay or

gain for any one unit of time*• If there is an equal amount of delay and gain

on a given day, the effects offset• Gain and delay quantum only applies to critical

activities• Float on near-critical paths must be ‘absorbed’

prior to counting delay

*Exceptions are with multiple shifts, rescheduling and changeof scope


Concurrency

Start delay and startgain in the same time

frame = concurrentdelay

Net impact for thesedays is zero


Concurrency

Two Start delaysin the same time

frame = concurrentdelay



�SUM OF NET DELAY FOR ALLWINDOWS MUST EQUAL TOTALDELAY EXPERIENCED ON THEPROJECT

• This is the Checking Mechanism



� Validate Results (An Iterative Process)• Is time consuming• Use contemporaneous documents to confirm

identified critical work activities – tied directly todelay causation

• Cross check documented delay events with thethen active schedule

• Consider sub-windows where work-aroundsoccurred to mitigate unforeseeable delayingevents

• Sum delay quantum of all windows is balanced


Window Analysis

SIMPLEEXAMPLE


ActivityID

OrigDur

Act Dur TotalFloat

0005 0 0 0

0010 5 0 0

0020 4 0 0

0030 4 0 0

0040 3 0 0

0050 3 0 0

0060 4 0 0

0070 0 0 0

Days-1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31

NTP

ACTIVITY A

ACTIVITY B

ACTIVITY C

ACTIVITY D

ACTIVITY E

ACTIVITY F

PROJECT COMPLE

© Primavera Systems, Inc

Start Date 13JAN00

Finish Date 04FEB00

Data Date 13JAN00

Run Date 13JAN00 17:38

Early Bar

Progress Bar

Critical Activity

Date Revision Checked Approved


ActivityID

OrigDur

Act Dur TotalFloat

0005 0 0 0

0010 5 0 0

0020 4 0 0

0030 4 0 0

0040 3 0 0

0050 3 0 0

0060 4 0 0

0070 0 0 0

Days-1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31

NTP

ACTIVITY A

ACTIVITY B

ACTIVITY C

ACTIVITY D

ACTIVITY E

ACTIVITY F

PROJECT COMPLE

© Primavera Systems, Inc.

Start Date 13JAN00

Finish Date 04FEB00

Data Date 13JAN00


Early Bar

Early Bar

Progress Bar

Critical Activity



ActivityID

OrigDur

Act Dur TotalFloat

0005 0 0 0

0010 5 0 0

0020 4 0 0

0030 4 0 0

0040 3 0 0

0050 3 0 0

0060 4 0 0

0070 0 0 0

Days-1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31

NTP

ACTIVITY A

ACTIVITY B

ACTIVITY C

ACTIVITY D

ACTIVITY E

ACTIVITY F

PROJECT COMPLE

© Primavera Systems, Inc.

Start Date 13JAN00

Finish Date 04FEB00

Data Date 13JAN00


Early Bar

Early Bar

Progress Bar

Critical Activity


x x

x

x x x x

o o o o

x

xo

ox x

x

x x- - - -

Delay Summary: 5 Delay Days – 1 Day Gained = 4 Days Delay



�Causation Analysis�Determine the Root Cause of Delay�Based on the following factors:

• Review of Project Documentation• Key Personnel Interviews• Technical Understanding• Other Analyses Performed

- Productivity Analysis- Project Management Analysis- Scope Change Analysis



�Responsibility Analysis�Determine Parties Responsible for Delay�Based on Following Factors

• Tie to Root Cause Analysis• Requires Expert/Professional Judgment• Must Reference Contract

- Defines Roles & Responsibilities Constituents

• Must Reference Project Delivery Mechanism- Defines Expectations of Constituents

SCHEDULE DELAY ANALYSISSCHEDULE DELAY ANALYSIS

NielsenNielsen--Wurster Asia PacificWurster Asia PacificFebruary 2004February 2004