Oct 25, 2023

A Method to the Madness: The Pitfalls of the “As-Planned vs. As-Built” Forensic Scheduling Analysis

Written by: Juan J. Miranda

     When selecting or defending against a litigation scheduling expert, a construction law practitioner must understand the scheduling expert’s methodology employed to evaluate project delays and the allocation of the fault for those delays. There are several forensic methods available, but courts have consistently viewed the “As-Planned vs. As-Built” (or “APAB”) methodology as the least reliable. A practitioner must be able to spot and criticize the use of APAB when used to evaluate scheduling delays on large and complex projects that deviate significantly from the project baseline schedules.

     The APAB’s unreliability is based on its inherent limitations, as recognized and defined by AACE International Recommended Practice No. 29R-03 Forensic Scheduling Analysis (the “Recommended Practice”). APAB is simply an observational basic method that “consists of analyzing the [baseline] schedule by examining a schedule, by itself or in comparison with another, without the analyst making any changes to the schedule to simulate any specific scenario[1].” The Recommended Practice thus classifies APAB “as gross as opposed to periodic because the analysis is performed on the entire project against a single baseline or other planned schedule rather than in periodic segments.” In other words, APAB does not account for actual events and activities that occur during the construction of a project.

     The Recommended Practice stresses that observational methods, like APAB, are applicable “to relatively simple projects and should not be used for long duration projects or where there are significant changes between the original planned work scope and the final as-built scope.” APAB  “is useful only for simple projects where the sequence of work did not vary significantly from the baseline schedule.” In short, APAB  is essentially “a comparison of an as-built schedule to just one set of as-planned network logic,” and therefore it should not be used to evaluate delays on large and complex construction projects.

     Courts disfavor the use of APAB for proving delay and fault because it assumes only one party is responsible for all of the project’s delay[2]. By using the APAB method, “a party simply subtracts the planned duration of a project from the actual duration of the project to identify the total delay to the work[3],” but without any analysis of the delay periods or proper efforts to ascertain concurrent or overlapping delays caused by others or other events. That is, the “cause” of the delay is assumed without proof, thus avoiding or bypassing a claimant’s burden to prove causation, by ignoring other causes, affecting the actual sequence of work, such as weather and subcontractor productivity. Because of the methodological flaws and limitations, some courts have rejected APAB entirely[4].

     For example, in Mega Construction Co., Inc. v. United States, 29 Fed. Cl. 396 (1993), the U.S. Postal Service terminated a $2 million fixed-price contract for cause due to the general contractor’s failure to comply with directives and abandonment of the work. In rejecting the contractor’s use of APAB to calculate delay damages, the court levied the following criticism:

The court does not view plaintiff's incomprehensible and suspect bar charts as demonstrating the critical path of the project, and no other evidence revealed the interdependence of the various activities of the project. The bar charts do not show the critical path, and thus do not permit a critical path analysis. At best, there may have been concurrent delay by both parties, but plaintiff made no attempt to apportion such delay[5].


Without a critical path analysis, the court cannot exclude the possibility that the contractor caused concurrent delay on the project. Plaintiff's charts are not sufficient to prove allocation between the parties or attribution to defendant. The court cannot rely on assertions of a contractor, not supported by a critical path analysis of the project, to award critical path delay costs. Neither did plaintiff show by a preponderance of the evidence that the claimed delays were of an unreasonable length and that any of the claimed work item delays caused material damage. This was insufficient to sustain plaintiff's contention that defendant's actions delayed the completion of the project by 272 days, or for any other quantifiable period of time. Plaintiff failed to prove entitlement to an equitable adjustment for delay to any work item, or project delay[6].

     The court rejected APAB as unreliable because it did not account for the interdependence of construction activities or segregate key details needed to allocate responsibility for the delay and determine its precise duration.

     National surveys evaluating the acceptability percentage of different scheduling delay methods also reflect the courts’ skepticism surrounding the use of APAB. APAB has been accepted in only 14% of the 57 cases surveyed, while more reliable methods have been accepted by courts up to 85% of the time[7]. In at least two studies, the APAB Method came in dead last in comparison to other methodologies[8].

     Although the APAB Method may at times be useful for evaluating delays on small projects that proceed in the sequence outlined in the baseline schedules, a practitioner should be highly skeptical of using the APAB Method on large and complex projects, particularly when there are significant deviations from the baseline schedules. When faced with evaluating delays on large projects, a practitioner and his expert should consider using a more robust methodology that considers concurrent delays, evaluates each parties’ fault for the delays, and requires the expert to evaluate project documents such as daily field reports, supervisor reports, meeting minutes, and photographs. In sum, a practitioner should always ensure that his expert, or that of his opponent, is employing a method that accurately reflects the reality of what occurred on the construction project.


[1] AACE International Recommended Practice No. 29R-03 Forensic Schedule Analysis.

[2] See, e.g., J. Wm. Foley, Inc. v. United Illuminating Co., 2013 Conn. Super. LEXIS 2028, 2013 WL 5422454, at *16 (Conn. Super. Ct. 2013) (calculating a total delay period and assigning responsibility to the defendant is "insufficient and of virtually no value").

[3] W. Stephen Dale & Robert M. D’Onofrio, Construction Schedule Delays §11.1 (2021).

[4] See, e.g., K-Con Bldg. Sys., Inc. v. U.S., 131 Fed. Cl. 275 (2017)(rejecting the APAB approach after finding that the method did not reflect that plaintiff did not actually perform in accordance with the schedule and did not reflect the reality of what occurred on the project).

[5] Id. at 435(internal citations omitted).

[6] Id. (internal citations omitted).

[7] W. Stephen Dale & Robert M. D’Onofrio, Construction Schedule Delays §12.3 (2021).

[8] Id.; see also, David Arditi & Thanat Pattanakitchamroon, Analysis Methods in Time-Based Claims, 134 No. 4 ASCE J. Const. Eng’g & Mgmt. 242 (Apr. 2008).