The document discusses the complexities of concurrent delays in construction projects, outlining definitions, types, and legal principles involved in analyzing these delays. It emphasizes the importance of understanding both prospective and retrospective analysis methods, as well as various approaches to determine entitlement for extensions of time and compensation. Additionally, it highlights how different jurisdictions treat concurrent delays and the implications of contractual mechanisms for resolving disputes related to such delays.

2. Navigating Concurrent Delays
in Construction
Identifying and Managing Concurrent Delays in Construction Projects

3. Mohamed Maged Hegazy
Associate Planning Director - Red SeaGlobal, LLM, MBA, BSc, MRICS, CCP, PMP
• Master in Construction Law – Salford University, UK
• Master of Business Administration – UoPeople, US
• B.Sc. Civil Engineering – Ain Shams University, Egypt
• Consultant – Saudi Council of Engineers
• MRICS, Chartered Project Management Surveyor – RICS
• CCP, Certified Cost Professional – AACE
• PMP, Project Management Professional – PMI
• P3O, Portfolio, Programme and Projects Offices – AXELOS, UK
• FIDIC Contracts Consultant, AIA (Brussels) Fellow
• Author of 50 Planning fundamentals & Fundamentals of Construction Contracts
• Experience more than 21 years in mega-projects (Buildings, Infrastructure &
Roads)

4. Session Information
• Learning Objectives:
1. Clarifying the definition challenges of the concurrent delay
2. Discussing the legal and contractual principles behind the analysis
approaches
3. Determining the entitlement in terms of extension of time and
compensation according to the analysis approaches
4. Reviewing the analysis approaches from the technical perspective
5. Addressing recommendations for contract drafting and post-contract
practices

5. My Related Publications
Fifty Scheduling Fundamentals & Fundamentals of Construction Contracts

6. CONTENT
1. Reasons and types of delay
2. Delay analysis approaches
3. Forensic scheduling
4. Concurrent delay
5. Contractual principles
6. Concurrency approaches
7. Extension of time claims
8. Recommendations
Reasons and
types of
delay
Delay
analysis
approaches
Forensic
scheduling
Concurrent
delay
Contractual
principles
Concurrency
approaches
Extension of
time claims
Recommend
ations

7. Reasons & Types of Delay
Neutral Event
In-Excusable
(Contractor - CRE)
Excusable (EOT)
Owner - ERE Concurrent
Delay
Pacing
Compensable Non-Compensable

8. Delay Analysis Approaches
Prospective TIA
Retrospective
-Simple and relatively simple
1- Overview of the facts
2-Comparing actual & planned progress
-Detailed, forensic and more reliable
3- Critical path analysis (CPA)
4- Focused methods of analysis:
Prospective: TIA -or- Retrospective:
window or time slice).
- Prompt Action – Prospective
Analysis - Do not 'wait and see’
(Contemporaneous Analysis)
- Analysis time-distant from the
delay event
Contemporaneous
After the Fact
Observational: Static, Dynamic –
Modeled: Additive, Subtractive

9. Retrospective Delay Analysis
Forensic Schedule Analysis:
A technical field of studying and investigating the schedule calculation using different methods (usually
requires many subjective decisions by professionals) to measure and quantify delay focusing on causation
to resolve EOT disputes.
Project Planning and
Scheduling
Forensic Schedule
Analysis
Legal Proceeding and
Aspects
No forensic schedule analysis method is exact. The level of accuracy of the answers produced by each
method is a function of the quality of the data used therein, the accuracy of the assumptions, and the
subjective judgments made by the forensic schedule analyst.
Legal considerations (3): Contractual requirements, ADR Forum & Legal requirements.
Technical considerations (3): Purpose, Data availability and reliability & Complexity of the dispute.
Practical considerations (5): Size of the dispute, Budget for analysis, Time allowed, Analyst experience &
Past history in the project).
WHICH TECHNIQUE TO USE – AACE RP?

10. More References
Additive,
Subtractive
& Analytical
Theoretical Based Methods
Actual Based Methods

11. Other Methods - Delay Quantification and Forecasting

12. Concurrent Delay Definition
Definitions
The delay events normally happen at different timings, during different periods, affecting different paths of
activities and with different effects. Therefore, it is challenging to specify what parameters to be adopted to
define the concurrency. In this regard, AACE mentioned numerous definitions as follows:
(1) SCL Protocol: The term “concurrent delay” is often used to describe the situation where two or more
delay events arise at different times, but the effects of them are felt (in whole or in part) at the same time. To
avoid confusion, this is more correctly termed the “concurrent effect” of sequential delay events.
(2) Concurrent delay occurs when there are two or more independent causes of delay during the same time
where most courts do not require that the period of concurrent delay precisely match. The period of
“concurrency” of the delays can be related to circumstances, even though the circumstances may not have
occurred during exactly the same time.
AACE differentiated between literal concurrency (true concurrency) and functional concurrency (concurrent
effect) considering that the functional theory recognizes the real-world limitations of exact measuring of
delays and inaccuracy of programmes.

13. Delay in Design
ERE #1
EOT??
Contract
Completion Date
Additional Work
ERE #2
Definition Variables
• Timing of the events
• Independency and relationships
• Duration of delay (Effectiveness)
• The effect (Delayed paths)
Lack of Resources
CRE #1
Concurrency???
Concurrency???

14. Simple Cases of Concurrent Delay
Concurrent Delay
(Excusable)
Compensable
(ERE exceeds CRE)
Non-Compensable
(CRE exceeds ERE)
ERE after Completion
(Net Method)
Excusable Delay (ERE)
In-Excusable Delay (CRE)
Excusable Non Compensable Delay
In-Excusable Delay
concurrent with
shorter Excusable
Delay yields a net
Excusable Non
Compensable
Delay
ONLY Time
Extension is
Granted
Should be
recovered
Excusable Delay (ERE)
In-Excusable Delay (CRE)
Excusable Non Compensable
In-Excusable Delay
concurrent with
longer Excusable
Delay yields an
Excusable Delay and
Partial Compensation
- Time Extension is
Granted with
prolongation cost
Excusable
Compensable

15. Legal Principles
1. Establishing Causation (Legal: breach or Factual: but for)
2. Prevention Principle
3. A Party Shall Not Benefit of Its Own Wrong
4. Contributory Negligence
5. Contractual Mechanism for Extension of Time
6. The "Dot On" Principle
7. Other Legislations - CMS

16. Causation
Causation is a term used in tort and contract. It is a topic that plays a key role when dealing with
commercial disputes.
Sometimes, one delay event may cause other delay events. In this case, these events are dependent, not
concurrent. It is a primary condition to have a concurrent delay which is that the delay events are
independent. This is one of the first checks to be done in analyzing the causation of the concurrent delay.
Overall, causation is a troublesome issue, particularly when there is a concurrent delay.
Legal Causation
One type of causation is legal causation. It analyzes the breached duty. In such cases, contract provisions
define the events that lead to the contractor’s entitlement to an extension of time.
Factual Causation
Factual causation checks the (proximate cause). The first step in establishing causation, after identification
of possible events, is to eliminate irrelevant causes with consideration of common sense. This is the
purpose of the “but for” test.
Mainly, the courts are concerned with assigning responsibility for the damage by identifying the effective
cause of them with consideration of common sense, not to explore all possible causes of a particular
incident.

17. Prevention
The emergent of the prevention principle goes back to the 1838 case of Holme v Guppy (building contract)
where the employer was not able to give possession of the site, so this prevented the commencement of
the work in the due time. The Court of Exchequer (appellate court) established what Baron Parke called
“clear authorities” stating that: “if the party be prevented, by the refusal of the other contracting party, from
completing the contract within the time-limited, he is not liable in law for the default … The plaintiffs were
therefore left at large”.
However, acts of prevention by an employer did not set time at large if the contract provided for extension of
time in respect of those events (Multiplex Constructions (UK) Ltd v Honeywell Control Systems Ltd, 2007).
In England: North Midland Building (2018), Judge Fraser J decided that the prevention principle is not an
overriding rule of public or legal policy. This means that the parties can agree to deal with the concurrent
delay in any other particular way, and the express terms prevail.
Twivy, in a SCL meeting in 2019, criticized the displacement of the prevention principle by express terms
relying on that it is an example of a very old principle of English law that a man shall not get benefits of his
own fault. Lord Finlay LC in New Zealand Shipping Co Ltd v Societe des Ateliers et Chantiers de France
(House of Lords, 1919) ascertained that: “this is regularly true in all cases: If that be a principle of law, that a
party shall not take advantage of its own wrong.”

18. Analysis approaches
Prospective vs Retrospective Delay Analysis
Overall, prospective analysis is helpful for the parties to move with lights on about the potential effect of the delay and the
extension of time entitlement. On contrary, it can never be accurate due to blindness about what will be the actual effects and
damages. Therefore, logic retrospective analysis is then required to move the assessment from foresight to hindsight.
All-or-Nothing Approaches. There are three approaches that lead to an all-or-nothing solution as follows:
- First-in line approach (sequential delay), Critical path definition. - Dominant cause approach (e.g., pacing situation).
The first-in line approach assigns responsibility of the delay to the first event of occurrence especially if the later event did not
cause additional delay. The delay caused by owner/employer can be considered as sequential, not an example of concurrent
delay because the project was already delayed by contractor and the employer events did not in fact cause any additional delay.
This approach of analysis does not reflect the effect of the culpable delay because it does not segregate the effect of each delay
event. So, this may lead to unfairness.
“Dominant” word can have several meanings such as operative, ruling, prevailing and most influential. However, this is not
always correct to assign liability based on a dominant cause because it deprives the contractor of its right.

19. Other Approaches
The major legal analysis approaches that focus on deciding the entitlement of extension of time are:
- Apportionment approach. - Full period EOT: Malmaison approach. - General rule (DeBeers & Walter Lilly).
Regarding the money-related approaches, the apportionment approach is a bit similar to the burden of proof approach
(Walter Lilly: Global claim & Arcadis UK Ltd v May and Baker, 2013) where both of them examine the parties’ responsibility
(causation)/ contribution to the damages but by using different methodologies. However, time is different from cost.
Malmaison approach, 1999 (English School as per Walter Lilly, 2012): “if there are two concurrent causes of delay, one of
which is relevant, and the other is not, then the contractor is entitled to an extension of time for the (full) period of delay
caused by the relevant event notwithstanding the concurrent effect of the other event.”
The apportionment approach (Scottish School: City Inn Case, 2007) examines contribution of the parties which is similar in
nature to contributory negligence or contribution among the joint wrongdoers if no dominant cause.
Brodie McAdam asserted that this was wrong because it could make a contractor charged with liquidated damages for a
period that acts of prevention by employer were operative during it.
In William F. Klingensmith Inc. (USA), the contractor sought a contract time extension plus impact costs where there were
concurrent delays. It was held: The general rule is that “[w]here both parties contribute to the delay, neither can recover
damage[s], unless there is the proof of a clear apportionment of the delay and expense attributable to each party.”
Blinderman, 695 F.2d at 559, quoting Coath & Goss. Inc. v. United States, 101 Ct.C1.702, 714-715 (1944). Likewise,
confirmed in Appeal of Coffey Construction Company Inc. VABCA No. 3661 (11 February 1993).

20. Summary of the Approaches
Dominant Cause
Approach
First-in Line
Approach
Apportionment
Approach
Time-but-no-money
Approach
Full period-
Malmaison &
Burden of Proof
Approach
In conclusion, USA/Malmaison approach looks mainly for the extension of time entitlement, and the
burden of proof approach can examine the entitlement of compensation and damages.
On the other hand, dominant cause (all-or-nothing) and Scottish apportionment approaches assign
the full liability to one party or apportion the liability of delays and decide the extension of time and
damages accordingly.
Overall, the “time but no money” approach can be considered a fair solution as an
application of sett off (no harm, no fool).

21. Contractual Mechanisms
The Standard Forms
Many contract draftsmen prefer to leave the problem of concurrent delay unaddressed. This results in little
guidance for any contract administrator in determining an assessment under the contract. Concurrent delay is not
obviously handled in the standard forms of construction contract such as AIA, FIDIC, JCT and NEC.
It makes it confusing when a concurrent delay takes place because no standard approach is adopted, and
different rules and procedures may apply under different jurisdictions.
Therefore, due to the absence of any express
provisions addressing concurrent delay, the
parties typically find themselves applying the
generic terms of the extension of time and using
those terms to make their arguments. Unless the
parties are able to reach an agreement, a
dispute may be referred to mediation,
arbitration, or the courts where a series of
common law principles will emerge and evolve.

22. Extending Project Duration
The “Dot On” Principle
The Net Method vs The Gross Method
The “dot on” principle adds the duration of the extension of time to the current completion date, not to the
date of the event (the gross method). Therefore, each time the contractor gets an extension of time, it
should be added contiguously.
Excusable Delay (ERE)
ERE #1
EOT #1
Contract
Completion
Date
Excusable Delay (ERE)
ERE #2
EOT #2

23. Special Case: ERE after the contract completion date
Excusable Delay (ERE)
ERE
In-Excusable Delay (CRE)
Contractor should
not be exonerated
Excusable Delay (ERE)
Extension of Time In-Excusable Delay
(LDs)
Contract
Completion
Date ASCE DAS 4.6: This type of delay
is referred to as “offsetting delay”
recognizing that an owner-caused
delay may result in recognizing a
noncompensable time extension to
offset all or a portion of any
potential liquidated damages.
SCL 10.14: Employer Delay to Completion does
not exonerate the Contractor for all its delays
prior to that Employer Delay to Completion
occurring. The effect of the Employer Delay
should be assessed and any EOT determined due
should simply be added to the contract
completion date.

24. Concurrent Delay – CMS (Other Jurisdictions)
- US: “No harm, no foul” rule applies and neither party may
benefit monetarily from the delay.
- Australia: The current Australian authorities favour the “first
in time” approach considering the sequential delays.
- Scotland: City Inn found that it must firstly be considered
whether there was a “dominant” cause of delay.
- Germany: Concept of concurrent causality as parallel but
independent contributions to causation.
- Austria: Austrian courts use the so-called “theory of
spheres”, through which it can be determined whether any
particular cause of a delay falls into the employer’s or the
contractors’ sphere of responsibility.

25. United States Approaches - Pacing
Similarly, in situations where the completion date is adjusted properly for change orders and the contractor is
behind schedule, owner delays that occur thereafter on a separate path may have a mitigating effect on
assessment of damages.
How is the issue of concurrent delay treated?
Parties are generally free, subject to the limitations of public policy and relevant legislation, to stipulate how
concurrent delay is to be defined and treated within their contract. In the absence of express provisions
dealing with the topic, general common law principles apply.
If concurrent delay is found to exist between events which would have otherwise entitled each party to claim
against the other, the so called “no harm, no foul” rule applies and neither party may benefit monetarily from
the delay. The contractor may not claim for the costs of delay and receives an extension of time so that the
employer does not recover delay damages.
Questions may arise as to whether one of the parties has intentionally delayed in response to the other
party’s delay – termed “pacing”. Generally speaking, pacing is legitimate and will not result in a finding of
concurrent delay, a principle often voiced by the phrase: “Why hurry up to wait?” However, parties taking
such action run the risk that the delay being responded to reduces or resolves in the future, or that
subsequent delay analysis shows the supposed pacing to be the original cause of delay.

26. Cases of law had found that any concurrent delay would deprive the parties of a financial remedy for delay
altogether. These cases pre-date critical path analysis and the popularity of liquidated damages clauses and
have now been overtaken by what is referred to as the “apportionment rule” whereby the court will attempt
to segregate delays were possible. This is not to be confused with the apportionment of liability for
concurrent delay based on relative fault as applied in some other jurisdictions (such as Scotland).
Apportionment in the United States refers simply to the process of allocating responsibility for different parts
of an overall project delay to individual parties based on a critical path analysis. Where such an analysis
shows specific delays to be concurrent, the “no harm, no foul” rule noted above applies and neither party
may claim financially in respect of those delays.
United States Approaches - Apportionment

27. Offsetting Delay – Critical/Longest Path
The treatment of offsetting delay has recently given rise to controversy as a result of the 2017 ASCE SDAS.
Delay which is not on the longest path to completion may nonetheless be treated in the same way as
concurrent delay if it would independently cause any activity to be delayed beyond the contractual
completion date as adjusted.
Ultimately the position depends on whether criticality is defined by reference to the contractual completion
date or by reference to the longest path to completion. There are cases supporting either approach: see for
example Framlau Corp, 71-2 BCA (CCH) and In re Fire Security Systems, Inc, 02-2 BCA (CCH) in favour of
offsetting delay being treated in the same way as concurrent delay and Electronic & Missile Facilities, Inc,
GSBCA No. 2787, 71-1 BCA for the opposite conclusion.
However, the more commonly accepted position (supported by the AACE RP-FSA) is against treating
offsetting delay in the same way as concurrent delay and to adopt the longest path to completion as the
basis for measuring criticality.
https://www.long-intl.com/articles/concurrent-delay/

28. AACE Cases of Concurrency

29. Technical Perspectives
Critical Path Analysis vs Longest Path Analysis Approaches
Applying this explanation to the legal analysis approaches can be against the first-in line approach (longest path) because the
second delay affects the programme paths with the same amount of delay as the first event plus an additional delay if any.
Therefore, it is only the “time but no money” approach (extension of time for the (full) period of delay caused by the change
order / relevant event without compensation) that complies with the technical point of view of the critical path analysis.
New Critical Path
CRE
Original Critical Path
Contract
Completion
Date
ERE Effect
ERE
EOT??
New Critical Path
ERE
Original Critical Path
Contract
Completion
Date
CRE Effect
CRE
EOT??

30. Logic and Common Sense
Unquestionably, critical path analysis is a helpful evidential tool, but it is not always determinative
as it has some limitations. For example, if there are insufficient records, the analyst will be in
serious difficulty. Furthermore, quality of data is crucial, and it may affect the correctness of the
analysis.
These limitations are clear from the fact that analysts may produce different assessments,
whether, or not, they have used the same data and methodology because of the level of subjectivity
and amount of assumptions they involve in identifying the sequence and interpreting results.
Therefore, as it is subjective in nature, it should consider applying common-sense tests.
The architect, amongst other things, must make a “logical analysis” in a methodical way of the
impact which the change orders / relevant matters had or were likely to have on the contractor's
planned construction schedule / programme." Logical analysis should be based on facts and
common sense in order to reach reliable results.

31. -Contractual entitlement
Typically, construction contracts contain provisions entitling the contractor to an extension of time on the
occurrence of a particular event provided the progress of the works or time for completion is delayed as
a consequence.
-Contractual compliance
Generally within an extension of time clause, the contractor will be obligated to submit notice(s) and
detailed particulars within a specified time frame.
-Governing Law
AIA 2017 - Construction: § 13.1 Governing Law.
The Contract shall be governed by the law of the
place where the Project is located.
EOT Claims Procedure

32. How is the question of evidence as to causes and
periods of delay dealt with?
In the United States, the parties appoint programming (schedule) experts/delay analysts as expert
witnesses; each such expert will select an appropriate method of analysis out of a number of
possible methods which are discussed in detail in AACE RP-FSA and ASCE SDAS some of which
are also included in the Society of Construction Law’s Protocol.
Whilst the choice of an appropriate method will be governed by a number of factors, including the
available evidence, there is a general preference for contemporaneous methods where possible (i.e.
those methods which assess the impact of delays by reference to contemporaneous evidence).
Choice of the Appropriate
Method

33. Recommendations
1. Clarity in contracts and law (definition, CP, TF ownership and consequences).
2. Official pacing notices, to consider the sequence of events and avoid constructive pacing problems.
3. Agreement on LDs for employer delay, SCL recommends that: “20.4 Arguments about proof of
loss could be reduced or avoided altogether if the contract contained an agreed amount per day that can be applied to
each day of prolongation. This is the reverse of the normal Employer's liquidated damages provision. It may be
necessary to have a number of different agreed amounts to be applied depending on the stage in the project.”
4. Due diligence of the mitigation duty by the contractor.
5. Partial taking over option can be applied as it may be for the sake of both
parties.
6. Caring about the soundness of the programme revisions.
7. The EOT entitlements should be reviewed and adjusted with time, until all effects of
delay events are revealed (retrospectively) because the predictions using the prospective analysis are not always
correct. However, it’s normally important to move with lights on and avoid the constructive acceleration problems.

35. Thank You
Don’t Hesitate to contact….
Mohamed Maged Hegazy
mm.hegazy@ppmconference.net
mobile : 00966-580264968