Extension of Time and Concurrent Delay in FIDIC Projects

Two events may delay the same project period: an employer's late instruction and a contractor's failure to procure equipment. Whether the contractor receives additional time or prolongation cost cannot be answered by declaring that both parties were late. Concurrent delay requires a contractual and technical examination of cause.

Establish the programme against which delay is measured

A baseline schedule is a starting point, not proof that every activity remained critical throughout the works. Updated programmes, actual progress, available work fronts and dependencies should be examined. The critical path may move as construction proceeds. A delay to a non-critical activity may not postpone completion, while a minor-looking late approval can affect an indispensable downstream sequence. The analysis should show the relationship between each event and the contractual completion date rather than compare only two dates at project start and finish.

Different causes can operate at the same time

True concurrency involves separate causes affecting completion during overlapping periods. An employer event may occur while the contractor is independently unable to progress, but overlap in calendar dates is not necessarily enough. The causal analysis must determine whether each event would have delayed completion and how the contract allocates the risk. Expert scheduling techniques can assist, but the selected methodology should match the reliability of the records. A model built from assumptions unsupported by site diaries, deliveries and instructions may create apparent precision without genuine proof.

Time and money may require different tests

An extension of time may protect a contractor from delay damages for a period attributable to an employer-risk event. Recoverable prolongation cost involves a separate inquiry into the contractual entitlement, actual expense, causation and any limitation arising from concurrent contractor delay. Parties should not assume that grant of additional time automatically carries compensation for all site overheads. The relevant FIDIC form and Particular Conditions may address both mechanisms through detailed claims provisions. The notice trail must therefore preserve time and monetary claims accurately.

Certificates and determinations require consistency

The employer, Engineer or representative may issue instructions, assess programmes and determine extensions under the applicable contract. The authority and duty of that decision-maker should not be assumed from a different FIDIC edition. A determination should address the material events, records and allocation of risk. If one party disputes the result, subsequent notices and dispute procedures must be followed. A later arbitration claim should be consistent with the contemporaneous reasons advanced, while allowing fair consideration of evidence that becomes available through the contractual process.

Prove cause, not simply overlapping dates

Concurrent delay is an evidentiary problem governed by a contract, not a convenient slogan for splitting responsibility equally. The strongest assessment identifies the true critical effects of each cause and distinguishes time relief from payment. Proper records and timely notices preserve the position long before expert reports are prepared.