Techniques and Methods for Assessing Delays
Time is important to everyone, especially to those in the construction industry. Every construction contract stipulates either a time of performance or a specific project completion date. Yet, with so much attention to time, construction projects are frequently subject to delays. Sorting out the issues and determining which party is responsible often proves difficult and time-consuming. Though many techniques are available for determining schedule impacts, not all produce valid results.
Just as network scheduling has become an important tool in managing a project, it has also become an important evidentiary tool in the presentation and defense of delay and disruption claims in litigation. Courts and boards have held that Critical Path Method (CPM) schedules are the most effective model for evaluating construction delays.
CPM is a network-based scheduling technique in which work activities with identified time durations are tied together with logic relationships indicating the flow of work. Once the time durations and logic relationships are identified, a mathematical calculation can be performed on the schedule network to determine the earliest and latest date each activity may be performed within the framework of the contract schedule. The longest path of interrelated activities through the schedule network is defined as the critical path.
Float is the amount of time a specific activity may slip before it affects project completion. Activities on the critical path have no float. In order to calculate delay damages, it is necessary to determine which work activities and delays were on the project’s critical path.
Delay analysis techniques can be classified into three separate categories: the Foresight Method, the Hindsight Method, and the Contemporaneous Method.
The differences between these delay analysis techniques involve the baseline schedule used for measuring the delay, the point in time when the delay is measured, and the treatment, if any, of concurrent delay.
The Foresight Method
Commonly thought of as the simplest and easiest, this method generally employs two approaches: Impacted As-Planned, where only the owner-caused delays are identified, and Adjusted As-Planned, where only contractor-caused delays are identified. In both approaches, the alleged delays are reviewed to determine where and how the revisions should be incorporated into the as-planned or baseline schedule. The result of these implanted activities is an adjusted project completion date, which demonstrates, either directly or indirectly, the owner’s impact on the contractor’s planned schedule of performance.
The Foresight Method is not generally favored by courts and boards, because it ignores the as-built history of the project; it produces theoretical results; it does not measure the effect of delay on actual performance; and it assumes that the as-planned schedule does not change.
The Hindsight Method
This method centers on an as-built schedule — a schedule depicting the dates that events actually occurred. Delaying events are normally depicted as distinct activities on the as-built schedule, which are invariably tied to the critical path. Typically, under this method, there are two approaches: As-Built Critical Path, which allocates time by determining the responsibility for the delays on the so-called critical path of the project and Collapsed As-Built, which removes delays caused by one party to determine when the work would have been completed if not for the delays of the other party.
The Hindsight Method presents a number of disadvantages that include difficulty determining which work activities or delay events controlled the pace of the work; not considering what was critical at the time a delay occurred; not considering float through various paths at different periods of time; not accounting for concurrent delay; and not attempting to determine the individual impact of each delay.
The Contemporaneous Method
The Contemporaneous Method hinges on the principle that in order to determine the impact of delaying events, the status of the project must be established at the time those events occurred. In essence, the schedule first needs to be updated at the time of the delay and, second, to be updated to incorporate any planning changes to coincide with the contractor’s plan for pursuing the work. The goal of this method is to develop a freeze-frame picture of the project — identifying the delaying event, the impact of the delay, and the plan to complete the remaining work at the time the delay occurred.
Two approaches are commonly used as part of this method: Time Impact Analysis, which looks at a particular point in time and utilizes a series of chronological time slices to evaluate major scheduling variations that occurred during the project, and Window Analysis, which examines the critical path between two points in time and assesses the delay as it occurs.
Courts and boards hold that contemporaneous schedule updates should be considered in evaluating delay. The Contemporaneous Method is favored because it provides a baseline for measuring delay; the status of the project at the time a delay occurs; the impact of delaying events on remaining work; and insight into float, changes to critical path, and revisions to the plan to complete.