A common misconception in construction disputes is that any delay caused by an employer-risk event entitles the contractor to an extension of time. Core Principle 6 of the SCL Delay and Disruption Protocol explains why this is wrong: only delay that affects the critical path of the works — that is, the longest sequence of activities that determines the project completion date — gives rise to an EOT entitlement.
The critical path is identified through the project's logic-linked programme. Activities on the critical path have zero float and any delay to them pushes out the completion date. Activities off the critical path enjoy float, and may be delayed without affecting completion until that float is exhausted. A delay event that affects only non-critical work, even if it causes real disruption on site, does not — without more — entitle the contractor to time.
This distinction is fundamental to the work of any delay expert witness. The first task in any delay analysis is to identify the contemporaneous critical path at the date of the delay event, and then determine whether the event impacted that critical path. Where the critical path itself shifts during the project (a phenomenon known as critical path migration), the analysis must follow the path as it actually was at each point in time.
In the Middle East, the use of FIDIC and similar forms means that the contract typically requires the engineer to assess the impact on the time for completion. This wording reinforces the SCL Protocol's emphasis on critical path analysis and discourages a broad-brush approach based on the gross duration of the delay event itself.
The Protocol also addresses the related concept of float. Float on a non-critical path generally belongs to the project, in the sense that whichever party first uses it benefits from it. A contractor cannot insist that float be preserved exclusively for its benefit, nor can an employer demand that the contractor compress its programme to free up float for the employer's use.
Understanding the distinction between critical and non-critical delay — and the role of float in the analysis — is essential for any party preparing or defending a delay claim in the region. It is also one of the first technical concepts that a delay expert witness will explain to a tribunal in oral testimony.