Key takeaways
- Method selection is driven by record quality, project stage and the contract — not by which result you prefer.
- A method the records cannot support will be dismantled long before quantum is argued.
- Contemporaneous windows analysis remains the most durable choice on well-documented projects.
Why the method matters more than the number
Every delay analysis produces a number of days. What determines whether that number survives is the reasoning that generated it: whether the baseline was reasonable, whether the as-built record is complete, and whether the analysis tested causation or merely correlated events with slippage.
The SCL Delay and Disruption Protocol sets out the families of technique in common use. In practice, the choice is constrained by four things: the quality and granularity of the as-built information, the stage of the project, the dispute-resolution forum, and the notice and records obligations imposed by your contract.
The four practical families
Each family answers a slightly different question, and mixing them mid-analysis is a common and fatal error.
- Time Impact Analysis — prospective, models the effect of an event on the schedule at the time it occurred. Strongest on live projects with maintained, statused schedules.
- Windows / time-slice analysis — divides the project into periods and measures critical path movement in each. The most durable retrospective method where monthly updates exist.
- As-planned versus as-built — compares intent to outcome. Accessible and intuitive, but weak on concurrency unless supplemented.
- Collapsed as-built (but-for) — extracts events from the as-built to infer what would have happened. Demanding of record quality and vulnerable where the as-built logic is reconstructed.
Concurrency, the perennial fight
Concurrent delay is where most analyses come apart. The threshold questions are whether the competing events were truly concurrent in effect rather than merely overlapping in time, and whether each was independently critical.
Our practice is to identify each delaying event, establish its own critical path effect, and only then consider interaction. Netting delays off against each other at the outset destroys the audit trail an adjudicator or tribunal needs to follow.
What we do first
Before selecting a method, we audit the record: schedule health across every update, progress reliability, the completeness of daily reports and correspondence, and whether notices were served as the contract required.
Where the record is thin, we say so and select a method the evidence can carry. Where it is strong, we use it — and the analysis becomes considerably harder to attack.
Written by Elite Analytics Claims Practice. For advice on a specific project or claim, get in touch.
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