Delay Analysis

A project finishes later than the original plan, and the delay could involve design changes, late materials, weather, rework or several events together. Delay analysis asks which events actually changed the completion path.

The Society of Construction Law Delay and Disruption Protocol provides guidance on extensions of time and delay compensation and emphasises transparent information and methods, though its guidance is not itself every contract governing rule. A baseline programme should identify activities, durations and dependencies, while actual progress records show what happened, since comparing only the first and last dates cannot explain the cause.

The critical path is the sequence that determines earliest project completion under the current schedule logic, and a delay to a noncritical task may use available float without shifting the finish. Criticality can change during the project.

A fictional build has a planned finish on day 100, and a design approval is late by ten days, but five days of available float absorb part of its effect under the validated programme. The illustrative finish impact may be five days, not automatically ten.

A schedule update should reflect actual completed work before a new delay is tested, because applying an event to an obsolete plan can give a false result, so record each analysis date and version. Check contemporaneous records such as meeting notes, site diaries, approvals, delivery logs and revised schedules, since later recollections can help but may be less reliable, and keep both favourable and unfavourable evidence.

Several delay methods exist, including prospective and retrospective approaches, and the suitable method depends on available records, contract wording and the question being answered. Concurrent events need careful examination as well, because two delays can overlap in calendar time without both independently affecting completion, and the legal treatment of true concurrency may vary by contract and jurisdiction.

A contractor may have a valid time extension without automatic payment of all extra site costs, because time entitlement and financial compensation are separate questions, and RICS discusses extension-of-time assessment and delay costs as distinct issues. Notice provisions can be material, since a contract may require prompt notice and particular supporting information, and delay analysis should not replace timely communication during the work.

Mitigation matters too, as teams may resequence work, add shifts or use alternate suppliers, and the analysis should record what was feasible and what was done without assuming every acceleration cost was reasonable. Disruption is not identical to delay, because work can become less efficient without moving the completion date and a delayed finish can occur without a measurable productivity loss.

An independent reviewer should be able to reproduce the calculation from the records and schedule versions, and hiding unfavourable changes weakens the analysis. Delay analysis explains schedule causation, not simply who to blame, so the final contractual outcome requires the actual agreement, evidence and often specialist review, while prevention is a useful by-product for management because it can reveal approval bottlenecks or unrealistic lead times.