April 8, 2019
There are three peer-reviewed institutional guides to forensic schedule delay analysis in the world. In terms of the many elements of delay analysis – do they all agree? Do they distinguish elements differently? If so, how? In the paragraphs below, I will examine how each of the guides treat major issues in forensic schedule delay analysis. The three guides each have slightly different purposes: the American Society of Civil Engineers’ “Standard for Schedule Delay Analysis” (October 2016 DRAFT) (ASCE) intends to establish a “standard [to] allow for segmentation of responsibility for delay to intermediary milestones and to the project completion date.” The ASCE document does not discuss specific methodologies, but instead considers only the overarching guidelines for such analyses. The UK-based Society of Construction Law’s “Delay and Disruption Protocol” (June 2016 Consultation Draft) (SCL) is intended to: “provide useful guidance on some of the common delay and disruption issues that arise on construction projects, where one party wishes to recover from the other an extension of time and/or compensation for additional time spent and the resources used to complete the project.” The SCL is intended for use both during the project as part of the management system, as well as after the fact in resolving disputes. Finally, the Association for the Advancement of Cost Engineering International’s “Recommended Practice on Forensic Delay Analysis: RP29R-03” (2011) (AACE) states it is intended: “to provide a unifying reference of basic technical principles and guidelines for the application of critical path method (CPM) scheduling in forensic schedule analysis.” Its focus is primarily on the methodologies and associated issues and is purely forensic.
Prior to 2002, forensic schedule delay analysis lacked any institutional guidance on methodology, theory, implementation, or practice. As a result, since the first CPM based forensic analyses were performed in the early 1960s, the experts doing this work had been expanding their methods and often naming them in a manner to achieve some brand recognition. The impact of the early development was a significant number of different methodologies, and even more names for methodologies as different practitioners attempted to distinguish what they did from other practitioners. Even with that, by the late 1990s, two key descriptors had emerged and become so common that they were used to describe virtually all delay methodologies: the “Windows” and “Time Impact Analysis” methods. Unfortunately, these names became so ubiquitous that virtually all manner of analyses came to be called one of these two names.
There were efforts both in the US and the UK, where virtually all of this development took place, to provide a systematized approach. Books such as Construction Scheduling: Preparation, Liability, and Claims” and “Construction Delay Claims in the US, and the UK book, Delay and Disruption in Construction Contracts, provided generally accepted names and methodologies regarding schedule delay analysis as well as providing a relatively complete review of the law associated with delay analyses.
In 2002, the Society of Construction Law published the first edition of the “Delay and Disruption Protocol.” (SCL). It proved to be very influential in the Commonwealth countries but had little impact in the US. In October 2016 the SCL issued a revised draft, called a “Consultation Draft,” in anticipation of a comprehensive revision in 2017. Discussion of the SCL in this paper is based on the “Consultation Draft.” Its publication in 2002, and a court-identified need for better support of expert opinions, as identified in Daubert (1993) and Kohmo Tire (1999), spurred the Association for the Advancement of Cost Engineering International to undertake a four-year development of the “Recommended Practice on Forensic Delay Analysis: RP29R-03” (AACE), first published in 2007.
Partially as a result of some unhappiness concerning AACE, the American Society of Civil Engineers started developing its Standard for Schedule Delay Analysis (ASCE). This standard has not yet been published in final form – the October 2016 draft is used for this paper. It is anticipated that the final version will be also available in 2017.
Each of these three documents covers a wide range of issues, and each has a slightly different coverage of issues related to schedule delay analysis. This paper will therefore focus on several of the more important issues that are addressed in the three expert guides: (1) methodologies; (2) critical path identification; (3) float; and (4) concurrent delay. The author recognizes that there are dozens of other topics that could be compared, but these four items cover many of the significant issues in schedule delay analysis.
Only AACE and SCL identify specific forensic delay methodologies. ASCE does not discuss individual methodologies. However, neither AACE nor SCL are “how-to” guides. Both assume the reader has at least a moderate amount of knowledge and experience in CPM schedules and schedule delay more generally. Readers interested in how to actually perform some of these methodologies will be disappointed and will have to search elsewhere for “how-to” guides.
One of the avowed purposes of AACE was to systematize the names of the methodologies. The AACE names are descriptive – they describe the characteristics of the methodology rather than using more commonly known names:
“The [AACE Recommended Practice] correlates the common names for the various methods to taxonomic names much like the biosciences use Latin taxonomic terms to correlate regionally diverse common names of plants and animals. This allows the common variations in terminology to coexist with a more objective and uniform language of technical classification.”
In this paper I will generally use more common names instead of the technical names identified in the AACE. There has been some criticism of the technical names because they have not emerged in common usage to replace the previous names. Interestingly, the numerical identifiers in AACE — its method implementation protocol (MIP) numbers — have become more commonly used by some analysts. For example, persons discussing AACE often refer to one of the common methodologies that is perceived as being accurate as “MIP 3.4.” This is a variation of the “windows” methodology that is done in two stages.
At the outset, AACE distinguishes between prospective and retrospective analysis. Prospective analysis is not covered in AACE since it concerns projecting what a delay will be, while retrospective identifies the delay after-the-fact, as it actually was. AACE importantly breaks down the retrospective methodologies into two large groups, one called “observational” and the other “modeled.” The observational methodologies generally take the CPM schedules as developed during the project “as-is,” while the modeled methodologies rely on the analyst to use schedule software to recalculate the schedules as part of the forensic process.
SCL uses different vocabulary to address this same idea. It calls methodologies that rely on calculations to the right of the data date as “prospective” methodologies. This is essentially the same as AACE’s “modeled” designation. SCL calls the other type of review as “retrospective,” whereas AACE calls this “observational.” One confusing aspect of SCL terminology is that all the methodologies described are “retrospective” in the sense that they are done after the fact, regardless of their “prospective” or “retrospective” designation. SCL distinguishes between how the delay is determined and how the critical path is determined. It is not clear what this distinction means.
SCL identifies six different methodologies. These methodologies utilize more conventional names, but even these names hide some significant differences with AACE. As an initial matter, SCL identifies that delay analysis can be divided into methodologies that identify effects, then correlate them to causes, or vice versa. The importance of this distinction is not explained, but a reasonable guess may be that this distinction influences the type of methodology adopted, depending on the type of information available for analysis. AACE also discusses the issues of cause-and-effect in some detail and suggests that forensic analysis should not change the approach during the analysis. Stated another way, each analysis should be entirely causal or entirely effect driven. AACE suggests to: “[U]se the cause theory where discrete delay events are identifiable and to use the effect theory where there are no identifiable discrete events that led to the delay.” ASCE does not discuss the issue of cause and effect specifically, but seems to take the position that effects should be the driving force in the critical path analysis, while causes are part of the entitlement analysis.
All three guides identify expert opinion as an essential component of any forensic delay analysis. SCL also observes that while software can be extremely helpful in performing the analysis, in the end a “practical analysis” may be required. ASCE does not address this issue directly, but recognizes that expert opinion based on the facts is necessary in virtually all situations. AACE observes in the opening sections that: “Forensic schedule analysis … relies upon professional judgment and expert opinion and usually requires many subjective decisions.”
AACE identifies nine different methodologies, and many of those can be modified in ways described in the AACE so as to change major characteristics. Nonetheless, for the purposes of this discussion, I will assume there are only nine methodologies. Not surprisingly, SCL’s six methodologies have significant overlaps with those of AACE. There are five methodologies that are common to both AACE and SCL, and general agreement as to how to perform these analyses. Recall, however, that neither of these guides are “how-to” manuals so they do not discuss the specific steps envisioned to execute the analysis. I note that the SCL Consultation draft considerably expands the list of forensic methodologies from the original 2002 edition.
It is noted that there are several methodologies that have no direct counterpart between the two guides. Two such AACE methodologies are specific types of windows methodologies. One is the bifurcated windows methodology, which is often considered the most accurate of all the available methodologies for forensic delay analysis in the US. The other windows-based methodology assumes that the analyst has made modifications to the logic/dates of the schedule updates to allow them to more accurately represent the contemporaneous plan. SCL does not discuss changes to the schedules when performing a forensic analysis. The ASCE guide devotes an entire section to the modification of schedules when performing a forensic analysis. It reads:
“Generally, there is a rebuttable presumption of correctness attached to the contemporaneous CPM schedules the parties used on the project. Therefore, the burden of proof of changing the schedules after they are prepared and used during the project lies with the party making the changes. As a result, any changes made after the fact should be made with good justification, be carefully documented, and explained.”
ASCE then goes on to indicate that it is generally preferable to modify contemporaneous schedules rather than abandon them. This reflects the overall position of the ASCE that a forensic analysis performed on a logic-driven schedule is preferable to some less reproducible methodology. AACE also addresses the issue of modifications of contemporaneous schedules, as indicated by the recognition that there is a methodology that might be using them. AACE reads: “[T]he smaller the number of modifications to the contemporaneous schedule updates, the more credible the results of the analysis.”
Surprisingly, SCL does not list the as-planned v. as-built methodology. This methodology is one of the oldest and most widely used in the world and is discussed by AACE. The methodology is also recognized to have significant defects when applied to larger, more complicated projects. Since its use is so prevalent in forensic analysis, it is a bit of a mystery as to why it is excluded from SCL’s list.
The AACE includes one other methodology not present in SCL. This is the collapsed as-built methodology done on a periodic basis. This is, in many ways, an obscure methodology, because the analysis starts at the end of the project, working back to the beginning, but also relies on schedule updates and use of contemporaneous stats. Recall that the traditional CAB methodology does not rely on contemporaneous schedules. This methodology does not appear in earlier versions of AACE’s RP – it was added in 2011. It may be that the methodology is used so rarely that it was excluded from the SCL list, or that is was considered part of the CAB methodology that was included.
The SCL also includes a methodology not present in AACE. The longest path analysis methodology appears to be similar to the CAB methodology in that it starts its analysis from a completed as-built schedule. SCL reads: “Once [the as-built is] completed, the analyst then traces the longest continuous path backwards from the actual completion date to determine the as-built critical path.” This methodology, therefore, is not based on CPM schedules, it is predicated on the analyst’s judgment as to delays and criticality. In the US this method is sometimes known as the “As-Built Critical Path” method and is generally viewed unfavorably by commentators:
“The As-Built Critical Path analysis … suffers from some noted defects that have relegated it to status of alternative or backup methodology. Indeed, some commentators, courts and tribunals do not consider the as-built critical path method as a critical path method (CPM) because it ignores float and the logic-driven portion of the CPM schedules.”
Overall, both the SCL and AACE guides agree on most of the major methodologies and describe their operation in similar terms. As previously noted, the 2002 version of SCL contained significantly fewer methodologies with considerably less discussion.
CRITICAL PATH IDENTIFICATION
Critical path identification is an essential item for any forensic delay analysis. Along with a responsibility analysis, it is the essence of a delay analysis. So how do the three guides discuss this? The discussion of the critical path is the first substantive discussion in ASCE. ACSE identifies that: (1) critical paths are dynamic, meaning they change over time; (2) critical paths are dependent on accurate updates; (3) critical paths must be critical to the then current schedule update; (4) delays should be measured at project completion; and (5) delays must be the sole reasons for delay to be compensable. None of these five ideas are particularly surprising, but the codification is clearly written and reflects the best technical thinking on the subject.
SCL largely agrees with these core principals, although not as clearly articulated. For example, the concept that a delay on the critical path means a change in the completion date seems to be assumed.
The dynamic nature of CPM schedules is also recognized as an essential characteristic of good management procedures in SCL. “[P]rogramming techniques that can have the effect of inhibiting a programme from reacting dynamically to change should be avoided.” The relevance of updates in the forensic process is also recognized by the SCL where it indicates: “The [extension of time] should be granted [by the owner] to the extent that the [owner-caused event] is predicted to prevent the works being completed by the then prevailing contract completion date.” This quotation also illustrates one of the fundamental differences between the SCL and the other two guides — SCL is intended to serve both as a guide to resolving time-related disputes during the construction as well as after-the-fact delay analysis. SCL also addresses the issue of the event being the sole cause of a compensable delay, as is discussed in the paragraphs on concurrency below.
AACE addresses these and other issues in great detail. It reads: “The critical path and float values of uncompleted work activities in CPM schedules change over time as a function of the progress (or lack of progress) on the critical and non-critical work paths in the schedule network.” AACE then goes further and identifies a forensic delay methodology’s ability to accommodate dynamic changes over time as a key element in its appropriateness for certain applications.
AACE does not specifically address the concept that the delay must be critical in the analysis period being examined. However, the sections discussing the identification of the critical path are the most detailed and extensive of any of the three guides. For example, some of the topics addressed by AACE include: longest path vs. total float; quantification of near-critical; identifying the critical path; critical path alteration techniques; and float ownership. As indicated by this list, the range of topics discussed in AACE’s RP is extensive. However, it notes: “It is impossible to accurately determine the as-built critical path by using only conventional float calculation on the past portion (left) of the data date. Because of this technical reason, the critical set of as-built activities is often called the controlling activities as opposed to critical activities.” This level of detail is unmatched in either of the other guides.
Essentially, all three guides deal in detail with the identification of the critical path through the analysis.
As identified in the previous paragraphs, float related issues are discussed in all three guides. In AACE the discussion of float starts with the observation that:
“Most practitioners would agree that the longest path is the true critical path. Even with the use of advanced techniques, if basic network rules … are observed the total float value is a reasonably accurate way of identifying the critical path. But, note that float values are displayed using workday units defined by the underlying calendar assigned to the schedule activity instead of in 7-day calendar units. Therefore, activities on a chain with uniform network tension may display different float values.”
AACE goes on to discuss the ongoing expert dispute concerning criticality of all negative float paths or the lowest of the negative float path as an indicator of the critical path. The issue is more than academic since those analysts who argue that all negative float paths are critical tend to find multiple critical paths in every delayed schedule. Most analysts identify the most negative float path as the critical path. At the same time, AACE specifies that identifying near-critical paths is an important analysis effort, in which relative float has a significant role:
“A rational system of identifying all activities and delays that are near-critical is the first step in objectively streamlining the process of evaluating the schedule for concurrent delays. *** Near-critical delays have the greatest potential of becoming concurrent delays.”
SCL contains little guidance on float. The primary instruction concerning the issue is that only delays that fall on the critical path are deserving of time extensions. If a delay occurs on an activity that has float, only when the float is exhausted and the activity comes on the critical path is the contractor entitled to an extension of time. Their specific instruction is unusually obscure:
“Unless there is express provision to the contrary in the contract, where there is remaining float in the programme at the time of an Employer Risk Event, an EOT should only be granted to the extent that the Employer Delay is predicted to reduce to below zero the total float on the critical activity path affected by the Employer Delay to Completion.”
Section 3 of the SCL identifies a potentially important difference between UK and US construction law. The paragraph indicates that the law is unsettled as to who owns the float if the contract is silent on the matter and recommends that the contract address this issue to forestall disputes. The SCL specifically identifies that this situation can arise when an owner delay consumes float and is followed by a contractor delay that is subject to liquidated damages.
ASCE contains detailed definitions of many items important to forensic delay. This includes a definition of float that follows mainstream thinking on the subject. ASCE also has a detailed discussion of the “problems” with float, including a detailed examination of how activities with no float can fall on non-critical paths due to constraints and multiple calendars. ASCE also makes clear the US construction law position that float belongs to the project: “In the absence of contract language shifting float ‘ownership,’ float is owned by the project. This means that float goes to the first party to use it.”
Perhaps the most important comments on float in ASCE concern the problems with excessive constraints and other efforts to control the project network in ways that make progress and delay calculation unreliable:
“Excessive constraints on activities that interfere with a logic-driven critical path should generally be avoided. In a constrained schedule, total float may be driven by constrained dates instead of the project end date. This becomes even more confusing when multiple constraints are used in the schedule, because which constrained date the total float value relates to must be determined, as there may be several in the CPM network. As a result, the use of constraints complicates the use of total float as a time-prioritizing tool.”
ASCE’s standard defines concurrency as follows: “[C]oncurrent delay can be described as a situation where two or more critical delays are occurring at the same time during all or a portion of the delay time frame in which the delays are occurring.” This definition contains some common definitional elements, some important clarifications, and, interestingly, is missing one element commonly found when characterizing concurrency. In detail:
- This definition says nothing about different parties, even though concurrency is irrelevant unless there are two or more parties causing the delays in question. However, it is safe to assume that the ASCE Standard understood that the delays were the responsibility of two separate parties. In the text immediately following this definition, the example given discusses owner and contractor caused delays.
- The definition requires the delays be at the same time. This precludes the thought sometimes promulgated that delays widely spaced in time. When there are two delays separated in time, but both occurring after contractual completion are sometimes considered “offsetting” delays. Such delays are not truly concurrent according to this definition.
- The definition makes clear that delays need only overlap in time. This important concept allows delays that do not start on the same day to be concurrent. One theory is that if one delay starts before the other, that initial delay creates float in the entire CPM network and all subsequent delays cannot be concurrent. If the delays start on the same day it is sometimes called “true concurrency.” This might be technically elegant, but it is not supported by case law.
- One concept common to this definition and most others is the idea of simultaneous critical path delays. This can easily happen when there are two critical paths during a particular period, but it becomes more problematic when there is only one.
AACE offers two definitions of concurrency followed by some explanatory detail: (1) Two or more delays that take place or overlap during the same period, either of which occurring alone would have affected the ultimate completion date. (2) Concurrent delays occur when there are two or more independent causes of delay during the same time period. AACE’s detailed examination clarifies concurrency by identifying four characteristics:
- Two or more delays that are unrelated and independent
- Either delay would have delayed the project even if the other delay did not exist
- Two or more delays that are the contractual responsibility of different parties, but one may be a force majeure event
- The delay must be involuntary
- The delayed work must be substantial and not easily curable
The AACE also discusses extensively the concept of simultaneity, using the terms “literal” and “functional” concurrency:
“Under the Literal Theory, the delays have to be literally concurrent in time, as in ‘happening at the same time.’ In contrast, under the Functional Theory, the delays need to be occurring within the same analysis period.”
In the “literal” theory, if the delays do not start at the same time, they are not concurrent. Under the this theory, the first delay to commence creates float in the entire network, so the subsequent delay is, by definition, not on the critical path and does not therefore delay the project completion. Some commentators, as well as AACE, have observed that exact simultaneity is impossible, but a more rational approach is to recognize that virtually all CPM schedules use a “day” as the smallest unit of time, so delays starting on the same day, regardless of what time in that day they started, are considered simultaneous.
Essentially, the AACE recognizes that as accurate a tool as a CPM schedule is, with its date-specific activity durations and detailed mathematical calculations, the measurement of the start or effect of specific event often cannot be measured with sufficient precision to distinguish certain impact events. The SCL definition of concurrency is as follows:
“True concurrent delay is the occurrence of two or more delay events at the same time, one an Employer Risk Event, the other a Contractor Risk Event, and the effects of which are felt at the same time. True concurrent delay will be a rare occurrence.”
The SCL commentary and discussion of the definition recognizes that: (1) if the effects of the delay are felt at the same time, then it might be considered concurrent, even if the delays occur at different times; (2) that the delay must delay completion; and (3) that CPM analysis is essential in determining concurrency. SCL also discusses the alternative concept that when one delay starts before the other, that first delay causes float in the second and thus there is no concurrency. SCL recognizes that while courts in the UK are divided on the subject, the preferred position is that there is no concurrency for delays that start on different days.
The assumption that the delay is caused by two separate causes is understood despite the absence of any discussion of the topic in either SCL or an authoritative commentary by John Marrin: “Concurrent Delay Revisited,” published by the Society of Construction Law.
In summary, all three guides discuss concurrency with some detail. There is agreement that: concurrent delays should start close in time to one another; that two or more parties are responsible for the different delays; that each delay, absent the other, must delay completion (be on the critical path) and; by implication, some near-critical path delays might be considered critical for the purposes of concurrency. Only the SCL DDP prefers the analysis that the two delays start on the same day in order to be concurrent.
Each of the guides devote considerable effort to discuss acceleration. ASCE starts with a rather complete summary of the subject: “Acceleration is the process of expending additional resources and/or costs to expedite contract performance. … Acceleration generally is segregated into three types: voluntary, directed, and constructive.” The guide then goes on to provide details on each of the three types of acceleration. While generally describing voluntary acceleration, ASCE fails to mention that such acceleration is quite common as contractors often accelerate to recover for their own delays. In the authors experience, this happens so frequently and with so little discussion that owners are often unaware of its occurrence.
Directed and constructive acceleration are discussed in simple terms with the five elements necessary for recovery of constructive acceleration discussed as follows:
“The contractor encountered an excusable delay, (2) the contractor made an appropriate time extension request, (3) the owner denied all or part of the time extension request or failed to act on it within a reasonable time, (4) the owner insisted the earlier completion date must be met or insinuated liquidated damages, and the contractor notified the owner that the alleged acceleration order was regarded as a constructive change, and/or (5) the contractor expended additional costs to accelerate performance.”
Only in the last paragraph of the guide does ASCE discuss the schedule implications, when they correctly note that only acceleration along the critical path improves on delay and that as a result of such acceleration, further acceleration on other, formerly non-critical paths may be necessary.
SCL’s discussion of acceleration is based almost entirely on what the contract says about payment for acceleration. Further, SCL provides no definition of acceleration. They do identify the important role of notice from the contractor to the owner concerning acceleration:
“Just because the Contractor implements measures to recover Employer Delay does not necessarily mean that the full costs of those measures were caused by the Employer Delay.”
AACE’s discussion of acceleration is more elaborate that either ASCE or SCL’s. At the same time, it covers essentially the same issues as ASCE, but in greater detail, including examples. The discussion of constructive acceleration identifies the same elements that ASCE identifies as prerequisite to recovery. In addition, AACE includes a discussion of acceleration of activities not on the critical path. Surprisingly, none of the three guides addresses the point that a contractor can recover for directed acceleration, even if no measurable acceleration is achieved. The general requirements are that: (1) the owner orders the contractor to accelerate; (2) the contractor reasonably attempts to accelerate; and (3) the contractor incurs costs in that effort.
Each of these three guides provides excellent and detailed information useful for forensic schedule delay analysis. While the common English language is a bit of a barrier, both the UK and US can learn from the guides produced across the sea. For example, both SCL and ASCE provide coherent discussions of underlying theoretical principals, while the AACE provides a much more detailed discussion of all the implications and assumptions that might be encountered while doing a forensic schedule delay analysis. The AACE guide also contains a specific section on issues associated with selecting a methodology, something generally absent from either SCL or ASCE. At the same time, ASCE provides excellent advice on best practices that all analysts should consider.
The greatest shortcoming of the three guides is that none provide a detailed “how-to” explanation of the different methodologies. This author’s observations are that there are relatively few “how-to” explanations available that follow the general guidance of the AACE or the standards of ASCE. This will likely be remedied by the AACE in the future (efforts are underway to revise the Recommended Practice RP29R-03), but that is likely years away. In the meantime, those performing forensic schedule delay analysis should be thoroughly familiar with the guides from their home countries and be able, should the need arise, to explain to clients, arbitrators, judges or juries why the analysis is the way it is and how that relates to appropriate guide(s).
 It could be argued that there is a fourth, the U.K. based Guild for Project Controls. This document does not yet have the same level of expert development and is largely based on AACE’s Recommended Practice on Forensic Delay Analysis, RP29R-03.
 ASCE, “ASCE Standard for Schedule Delay,” DRAFT of October 2016.
 Society of Construction Law Delay and Disruption Protocol (June 2016 Consultation Draft).
 . K. Hoshino, J. Livengood, and C. Carson, “RP 29R-03 Forensic Schedule Analysis,” AACE International, Morgantown, WV. (2011).
 J. Wickwire, T. Driscoll, S, Hurlbut, and M. Groff. “Construction Scheduling: Preparation, Liability, and Claims”. Wolters Kluwer, 3 Ed. (2010)
 B. Bramble and M. Callahan. “Construction Delay Claims.” (2000), (3d ed. Supp 2010), Aspen Publishers, New York.
 Daubert v. Merrell Dow Pharmaceuticals, Inc., 113 S. Ct. 2786 (1993).
 Kumho Tire Co. v. Carmichael, 526 U.S. 137 (1999).
 ASCE Standard, DRAFT of October 2016.
 There is no good single source for how-to guides. Further the many different sources often depict slightly different methodologies when discussed in detail. AACE Annual Meetings often have detailed presentations on how to perform an analysis. See www.AACEi.org.
 AACE RP29R-03 (2011) @ 1.4.
 A. Ness, “Delay Analysis – Some Big Unanswered Questions,” ABA Construction Forum, October 2016.
 AACE RP29R-03 (2011) @ 3.5 does provide for adjustments to the contemporaneous schedules. This is discussed later in this paper
 Society of Construction Law, “Delay and Disruption Protocol” Society of Construction Law, London, June 2016 (Consultation Draft) @ 6.5 d and 6.5.e
 SCL-DDP June 2016 @ 6.5.
 SCL-DDP June 2016 @ 6.5June.
 SCL-DDP June 2016 @ 6.4.a.
 AACE RP29R-03 (2011) @ 4.2.D.3.
 ASCE Standard, October 2016 @ 9.1.
 SCL-DDP June 2016 @ 6.4.c.
 ASCE Standard, October 2016 @ 10.2. 10.4 & 10.5.
 AACE RP29R-03 (2011) @ 1.1.
 But See: SCL-DDP June 2016 @ 5.8.
 ASCE Standard, October 2016 @ 10.
 ASCE Standard, October 2016 @ 10.3
 ASCE Standard, October 2016 @ 1 and 2.
 AACE RP29R-03 (2011) @ 3.5.
 AACE RP29R-03 (2011) @ 3.5.L.
 N. Braimah. “An Investigation into the Use of Construction Delay and Disruption Analysis Methodologies.” Doctoral Thesis, University of Wolverhampton (UK) August 2008.
 . J. Wickwire, T. Driscoll, S. Hurlbut, and M. Groff. Construction Scheduling: Preparation, Liability, and Claims. Wolters Kluwer, 3 Ed. (2010), Section 9.06[D].
 AACE RP29R-03 (2011) @ 3.1.
 AACE RP29R-03 (2011) @ 3.9.
 SCL-DDP June 2016 @ 6.6 (d).
 S. Dale, and R. D’Onofrio. Construction Schedule Delays, Thomson Reuters, 2015 @ 9.1
 ASCE Standard, October 2016 @ 4.
 SCL-DDP June 2016 @ 3.3.
 SCL-DDP June 2016 @ 1, 2.49.
 SCL-DDP June 2016 @ 5.7.
 AACE RP29R-03 (2011) @ 1.5.A.
 See for example, AACE RP29R-03 (2011) @ 3.1.E and 5.5.
 AACE RP29R-03 (2011) @ 4.3.
 AACE RP29R-03 (2011) @ 4.3.C.
 AACE RP29R-03 (2011) @ 4.3.A.1.
 AACE RP29R-03 (2011) @ 4.3.B.
 SCL-DDP June 2016 @ 3.8.3.
 R. D’Onofrio, “Can There Be Float on the Critical Path?” ABA Newsletter, Under Construction, Vol. 11, No. 3, August 2009.
 ASCE Standard, October 2016 @ 3.
 ASCE Standard, October 2016 @ 5.1.
 ASCE Standard, October 2016 @ 5.2.
 ASCE Standard, October 2016 @ 5.3.
 ASCE Standard, October 2016 @ 7.2.
 ASCE Standard October 2016 @ 8.1.
 J. Livengood, “Offsetting Delays, the Owners Friend.” Cost Engineering, AACE International, Morgantown, WV, Jan., 2012.
 V. Ostrowski & M. Midgette, “Concurrent Delay Analysis in Litigation,” Cost Engineering, Vol. 48, No. 1 (January 2006).
 AACE RP29R-03 (2011) @ 4.2.D.1.
 AACE RP29R-03 (2011) @ 4.2.D.1.
 AACE RP29R-03 (2011) @ 4.2.D.1; See also Richard Long, Analysis of Concurrent Delay on Construction Claims (2013).
 V. Ostrowski & M. Midgette, “Concurrent Delay Analysis in Litigation,” Cost Engineering, Vol. 48, No. 1 (January 2006).
 AACE RP29R-03 (2011) @ 4.2.D.1; Richard Long, Analysis of Concurrent Delay on Construction Claims (2013).
 J. Livengood & T. Peters, “The Great Debate: Concurrency vs. Pacing Slaying the Two-Headed Dragon,” AACE International Transactions (2008).
 SCL-DDP Delay and Disruption Protocol, The Society of Construction Law (Oxford 2002).
 SCL-DDP June 2016 @ 3.10.4.
 CL-DDP June 2016 @ 3.10.5.
 SCL-DDP June 2016 @ 3.10.6.
 SCL-DDP June 2016 @ 3.10.10.
 SCL – DDP Delay and Disruption Protocol, The Society of Construction Law (Oxford 2002).
 J. Marrin, Concurrent Delay Revisited, Society of Construction Law (2013).
 ASCE Standard @ 11.
 ASCE Standard, October 2016 @ 11.3.
 ASCE Standard, October 2016 @ 11.4.
 SCL-DDP June 2016 @ 3.12.6.
 AACE RP29R-03 (2011) @ 4.4.C.
 AACE RP29R-03 (2011) @ 4.4.B.1.
 J. Wickwire, T. Driscoll, S, Hurlbut, and M. Groff. “Construction Scheduling: Preparation, Liability, and Claims”. Wolters Kluwer, 3 Ed. (2010) @ 7.10 [A].