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Surety Association of New Jersey
Delay Analysis & Construction Scheduling
March 25, 2010Presented by:
William M. Wolf, Jr., P.E.Capital Project Management, Inc.
2
Credentials - William M. Wolf, Jr., PE
Over 35 Years of Engineering and Construction Experience
Design On-Site Project Representative Estimating Services Surety Consultant Dispute Resolution Services
Preparation and Defense of Construction Contract Claims
Testimony CPM Scheduling Services
3
Introduction Involved in a variety of default situations
during my career Issue always asked by parties involved in
default situation: “Who is responsible for the delay and how
do we prove it?” Delay Analysis Based on the Construction
Schedule
4
What is a Construction Schedule and How is it Used?
Schedule and coordinate the work Monitor and control progress Evaluate and document changes Prove or defend delay claims
5
Common Types of Schedules
The “Gantt” Chart – Bar Chart
Network Analysis System - CPM
Bar Chart ScheduleMonths1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Excavate
Foundations
Structural Steel
Roof
CurtainwallProcure Steel
Coordination Drawings
Fab. & Deliver
MEP Rough-In
MEP Finishes
Interior Finishes
Punchlist
2
3
2
3
3
4
4
1
4
1
3
3
7
Network Schedule
Representation of a project plan by a network that depicts the duration, sequence and interrelation of the work activities
Critical Path Method – “CPM”
Network ScheduleMonths1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Excavate
2 Foundations
3 Structural Steel
4
Roof
1
Curtainwall
4Procure Steel
3
Coordination Drawings
3Fab. & Deliver
2
MEP Rough-In
3 MEP Finishes
3
Interior Finishes
4 P.L.
1
Critical Activity
Logic Relationship
Foundations
Curtainwall
Duration in Months3
9
Definitions
Critical Path - longest path (or sequence) of activities through the network
Float - the amount of time an activity can slip without impacting project completion (contingency time)
Network ScheduleMonths1 2 3 4 5 6 7 8 9
Excavate
2Foundations
3Structural Steel
4
Procure Steel
3Float
2 months
Critical Activity
11
Schedule Updates Status progress of work
Determine remaining duration of activities Record actual dates (as-built) Make necessary logic revisions Incorporate change orders Reschedule remaining work
Schedule is dynamic
Progress as of Month 3Months1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Excavate
2 Foundations
3 Structural Steel
4
Roof
1
Curtainwall
4Procure Steel
3
Coordination Drawings
3Fab. & Deliver
2
MEP Rough-In
3 MEP Finishes
3
Interior Finishes
4 P.L.
1
Foundations
Curtainwall
0
1
2
100%
60%
30%
0%
Schedule Update as of Month 3Months1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Excavate
Foundations
2 Structural Steel
Roof
1
Procure Steel
3
Coordination Drawings
1Fab. & Deliver
2
MEP Rough-In
3 MEP Finishes3
Interior Finishes
4 P.L.
1
Curtainwall
Foundations
Completion slips 1 mo.
3/11/6
1/9
3/5
14
Using CPM Schedule for Delay Analysis
Establish reasonable Baseline schedule Evaluate schedule updates and planning
changes Evaluate delays chronologically using
current project schedule Reflect as-built information Thoroughly base analysis on the project
records
15
Definitions
Baseline Schedule – the contractor’s plan and intention of performing the scope of work in conformance with the contract requirements (“As-Planned” Schedule)
As–Planned Schedule - Office BuildingMonths1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Foundations
Structural SteelRoof
Curtainwall
Interior Finishes PunchListCoord. Dwgs.
Fab/Deliver MEP Rough In MEP Finishes
NTP
4
4
1
3
33
4
4
3
1
17
Definitions
As-Built Schedule A schedule depicting the actual historical
record of events, activities and progress that happened during execution of the given project
Involves time-consuming research of project records
B&C
2001
2001
2002
2002 2003
2003
J JJ JJJ A AS SO N D F M A M O N D F M
Site Work
Precast
Cast In Place
Masonry
Roofing
Interior Finishes / Flooring
Security System
Mechanical
Electrical
Beams
Total project delay 332 days
Grade Beams
CMU Walls and Columns
Brick Work
Place and Grout Planking
Set Cells
Roof Tile Installation
Roof/Ceiling Framing
Drywall
Paint
Substantial Completion
Cell Doors & Windows
Relocate/Install Communes
& Temp Power R/I Bsmt R/I Basement & Cell Area For A, B & C
Pull Wire Trim Out Punch List
Mechanical Fixtures Trim Out
Drains
Chiller Piping
R/I Basement & Cell Area For A, B & CSet Drains
Misc PLM Repairs
Utilities Removal
Relocate/Install
Gasline/Water/
Storms & Sanitary
Install Piping
HVAC HangersC&A Area
Grills/Ductwork to ACU
SetEquip
Insulate, Adjust &
& Balance
Start up Equip Punch List
Adjust & Install Cameras
Set CNTLS
Adjust Doors/Instl Window Sensors
Paint
Ceilings/Hallways
Frame RoofHips & Dormers A&B
Frame Roof C Frame CLG A
A&B Area C Area
Crane on Site
Set SteelFraming
A&B Area A&C Area
Brick Work A & B Coping Stone
A-wing
Face BrickExercise YD
CMU Exercise YD
CMU Walls & ColumnsB Area & Basement/C&A Walls/C2 Area
Begin GroutBsmt
StripExcavate
BsmtBsmt/Misc Site Work
Backfill Bsmt
Fence
Set Cells A&B Grout & Repair Rub Cell
WallsOver Bsmt
MechRm
C Wing 2nd Flr
C Wing 2nd Flr
ClgDelv Rebar
Pipes Drill & PourPiers & Pier Pads
Bsmt Form & Pour Walls Slabs A,B,&C A/Seg Unit
Pour Floor Topping A,B
LT WT Conc 2C
Ramps/Walks At Entrance
Ramp & Ret Wall
West Wall
BM Sides Bsmt Area
Cantil Wkwy
EL BMS C Area
Clg BMS
2C
Fire Lane Punch List &
Corrective WorkRepair & Replace Brick Work
Coping Stone
Grade Beams/Walls/Mech Pads/SlabsPiers
Mech Pads
Elev Bms
Grade Beams Bsmt A,B&C Area
Contract Completion
J JJ JJJ A AS SO N D F M A M O N D F M
Structural Steel
As-Built Schedule
19
Result of Delay Analysis
Critical Delay – Delay affecting an activity on the critical path of a project — impacts project completion
Non-Critical Delay – Delay which absorbs float — does not impact project completion
Network Schedule
Months1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Excavate
2 Foundations
3
3
Coordination Drawings
3Fab. & Deliver
2
MEP Rough-In
3Critical Activity
Logic Relationship
Procure Steel
FloatNon-Critical
Delay
2
Critical Delay
2 4
4
3
Roof
1
MEP Finishes
Structural Steel
Interior Finishes
1
Curtainwall
4 P.L.
2 mos.
Network Schedule
Months1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Excavate
2 Foundations
3
Coordination Drawings
3Fab. & Deliver
2
MEP Rough-In
3Critical Activity
Logic Relationship
4
Structural Steel
Roof
1
MEP Finishes
3
Interior Finishes
1
Curtainwall
4
4 P.L.
Float
Procure Steel
3
Non-Critical
Delay
Critical Delay
Float
2 mos.
22
Categories of Critical Delay
Excusable Delay – Delay that excuses late performance Compensable –Contractor reimbursed
for time-related costs Non-compensable –Contractor is
precluded from reimbursement for time-related costs
Non-Excusable Delay – Delay within the control of the Contractor
23
Concurrent Delay
Two or more delays occurring in the same time frame on separate critical paths with both affecting the overall completion of the project
Concurrent delays prevent either party from recovering damages
Foundations
Coord. Dwgs.
NTP
4
3
SteelDelay
2
MEP Changes
21
Concurrent Delay
Months1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
2 Months
Foundations
Structural SteelRoof
Curtainwall
Interior Finishes PunchListCoord. Dwgs.
MEP Rough In MEP Finishes
NTP
4
4
1
3
3
4
4
3
1Fab/Deliver
3
3 33
Fab/Delv.
Structural SteelRoof
Curtainwall
Interior Finishes PunchList
MEP Rough In MEP Finishes
4
1
4
4
1
ExcusableNon-compensable
25
Delay Analysis Techniques
Contemporaneous Method Establishes the status of work at the time a
delay occurred to measure delay (i.e. Time Impact Analysis)
Foresight Method Uses as-planned schedule as baseline to
measure delay (i.e. Impacted As-Planned) Hindsight Method
Uses as-built schedule or actual history to measure delay (i.e. Collapsed As-Built)
Contemporaneous Method:
Time Impact Analysis
27
Time Impact Analysis
Chronological and Cumulative Approach Utilizes a series of chronological “time
slices” to explain the major schedule variations that occurred during the course of the project.
Technique relies upon: As-planned schedule Contemporaneous schedule updates Development of an as-built schedule
Foundations
Coord. Dwgs.
Fab/Deliver
NTP
4
3
3
SteelDelay
2
Time Impact Month 6 – Steel Delay
Months1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
2 MonthsStructural Steel
Roof
Curtainwall
Interior Finishes PunchList
MEP Rough In MEP Finishes
4
1
3
4
4
3
1
Foundations
Structural SteelRoof
Curtainwall
Interior Finishes PunchListCoord. Dwgs.
MEP Rough In MEP Finishes
NTP
4
4
1
3
3
4
4
3
1Fab/Deliver
3
Foundations
Coord. Dwgs.
Fab/Deliver
NTP
4
3
3
SteelDelay
2
Months1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
2 MonthsStructural Steel
Roof
Curtainwall
Interior Finishes PunchList
MEP Rough In MEP Finishes
4
1
3
4
4
3
1
Foundations
Structural SteelRoof
Curtainwall
Interior Finishes PunchListCoord. Dwgs.
MEP Rough In MEP Finishes
NTP
4
4
1
3
3
4
4
3
1Fab/Deliver
3
Time Impact Month 6 – Steel Delay
Foundations
Coord. Dwgs.
Fab/Deliver
NTP
4
3
3
2
Months1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
2 MonthsStructural Steel
Roof
Curtainwall
Interior Finishes PunchList
MEP Rough In MEP Finishes
4
1
3
4
4
3
1
Ironworkers Strike
ExcusableNon-compensable
Foundations
Structural SteelRoof
Curtainwall
Interior Finishes PunchListCoord. Dwgs.
MEP Rough In MEP Finishes
NTP
4
4
1
3
3
4
4
3
1Fab/Deliver
3
Time Impact Month 6 – Steel Delay
Foundations
Coord. Dwgs.
Fab/Deliver
NTP
4
3
3
2
Months1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
2 MonthsStructural Steel
Roof
Curtainwall
Interior Finishes PunchList
MEP Rough In MEP Finishes
4
1
3
4
4
3
1
DesignChanges
ExcusableCompensable
Foundations
Structural SteelRoof
Curtainwall
Interior Finishes PunchListCoord. Dwgs.
MEP Rough In MEP Finishes
NTP
4
4
1
3
3
4
4
3
1Fab/Deliver
3
Time Impact Month 6 – Steel Delay
Foundations
Coord. Dwgs.
Fab/Deliver
NTP
4
3
3
2
Months1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
2 MonthsStructural Steel
Roof
Curtainwall
Interior Finishes PunchList
MEP Rough In MEP Finishes
4
1
3
4
4
3
1
Fabrication Delays
Non-excusable
Foundations
Structural SteelRoof
Curtainwall
Interior Finishes PunchListCoord. Dwgs.
MEP Rough In MEP Finishes
NTP
4
4
1
3
3
4
4
3
1Fab/Deliver
3
Time Impact Month 6 – Steel Delay
33
Time Impact Analysis
Strengths Preferred methodology Measures schedule impact at inception of
delay Considers float and critical path Truly historical because it considers the
basis for management decisions at the time
Thorough and difficult to attack quickly
34
Time Impact Analysis
Disadvantages Complex to assemble Challenging to complete without
proper project documentation Delay quantum builds on previous
analysis (“time window”)
Foresight Method:
Impacted As-Planned
36
Impacted As-Planned
Process of inserting actual project delays into the as-planned (baseline) schedule without considering the actual progress of the project
Schedule maintains original logic and durations
Does not require the development of a detailed as-built schedule
As–Planned Schedule - Office BuildingMonths1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Foundations
Structural SteelRoof
Curtainwall
Interior Finishes PunchListCoord. Dwgs.
Fab/Deliver MEP Rough In MEP Finishes
NTP
4
4
1
3
33
4
4
3
1
Impacted As–PlannedMonths
Foundations
Coord. Dwgs.
NTP
4
3
SteelDelay
2
MEPChanges
21 3 33
Fab/Delv.
Structural SteelRoof
Curtainwall
Interior Finishes PunchList
MEP Rough In MEP Finishes
4
1
4
4
1
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
1
1
ContractCompletion
4 Months
ActualCompletion
1 Mo.
DetailConflict
Lateselections
Maintains planned dates from baseline schedule
39
Impacted As-Planned
Weaknesses Project may not have been built
according to the baseline schedule Ignores as-built data Almost always overstates the
delays Not accepted by the courts
Hindsight Method:
Collapsed As-Built
41
Collapsed As-Built
After-the-fact analysis of project schedule (Retrospective)
Detailed analysis using as-built data Removes specific delays from as-
built schedule Results in as-built schedule “but for”
identified delays
Collapsed As–BuiltMonths1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Coordinated Dwgs.
Fabricate/Deliver
NTP
4
6
3
Structural Steel
Foundations
Roof
Curtainwall
PunchList
MEP Rough In
MEP Finishes
6
2
5
5
1
3
4
Interior Finishes
Collapsed As–BuiltMonths1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Fabricate/Deliver
NTP
4
6
3
Foundations
Roof
Curtainwall
PunchList
MEP Rough In
MEP Finishes
7
2
5
5
1
3
4
Interior Finishes
SteelDelay
MEPChanges
DetailConflict Late
selectionsCoordinated Dwgs.
Structural Steel
Collapsed As–BuiltMonths1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Coordinated Dwgs.
NTP
4
3
Foundations
PunchList
1
Fabricate/Deliver
3 MEP Rough In
MEP Finishes3
4
4
Structural Steel
Roof
Curtainwall
5
2
4 Interior Finishes
ContractCompletion
3 Months
45
Collapsed As-Built
Weaknesses Not reconciled with contemporaneous records such as monthly updates
Doesn’t consider float at inception of delay or identify “critical delays”
Unrealistic representation of what happened on project
46
Areas of Potential Conflict
Ownership of Float Right to finish early Reasonableness of baseline
schedule Accuracy of updates/schedule
manipulation Methodology for time extensions
47
In Summary. . .
Schedule delay analysis should consider: Baseline schedule Contemporaneous schedule updates Critical path and available float As-built history of project Chronological & cumulative accounting of delays Progress achieved up to the point in time when the delay
occurred Concurrent delays
Analysis must be thoroughly grounded in the project records
Surety Association of New Jersey
Delay Analysis & Construction Scheduling
March 25, 2010Presented by:
William M. Wolf, Jr., P.E.Capital Project Management, Inc.