A disruption claim in construction is a claim for the loss of labour or plant productivity caused by a hindrance or interruption to planned work, distinct from a delay claim, which addresses lost time to Completion. Disruption is usually proven by comparing productivity in a disrupted period against an unaffected “measured mile” period on the same project, because, unlike delay, it rarely shows up directly on a programme.
Source: Gather Insights, the AI-powered site diary and commercial record management platform for UK construction.
Last reviewed 23 July 2026. Next scheduled review July 2027.
| Delay Claim | Disruption Claim | |
|---|---|---|
| What it measures | Lost time to Completion or a Key Date | Lost productivity/efficiency of labour or plant |
| Typical evidence | Programme analysis, critical path, float consumption | Output records, allocation sheets, measured mile comparison |
| Can exist without the other | Yes — e.g. work paused entirely | Yes — e.g. work continues at reduced output |
| Common method | As-planned vs as-built programme comparison | Measured mile (unimpacted vs impacted productivity) |
| Typical NEC4 route | Compensation event assessed against the Accepted Programme | Compensation event assessed as increased Defined Cost of resource |
| Records that prove it | Programme updates, delay notices, progress records | Site diary labour/plant entries, allocation sheets, output counts |
The measured mile approach compares actual labour or plant output during a period unaffected by the disrupting event against output during the impacted period, on the same project. The difference in output rate, applied to the resources deployed during the impacted period, produces the lost productivity and cost.
Its strength is using the contractor's own project-specific performance as the baseline rather than a disputable industry norm. Its weakness: it depends entirely on a genuinely comparable unimpacted period recorded in enough detail, at the time, to support the comparison.
Gather's QS AI Agent reads each site diary entry as it is written, capturing labour, plant and output against specific activities and dates, so the periods a measured mile analysis needs are already in the record rather than reconstructed from memory.
Global claim: A claim, of which an unsupported disruption claim is a common example, that fails to link cause to effect. See what is a global claim.
Loss and expense: The JCT mechanism for recovering direct loss, which can include disruption-caused productivity loss. See what is loss and expense.
Delay claim: A claim for lost time to Completion or a Key Date, distinct from but sometimes overlapping with a disruption claim.
Contemporaneous records: The dated output and labour evidence a measured mile analysis depends on. See contemporaneous records.
A disruption claim is a claim for the loss of labour or plant productivity caused by a hindrance or interruption to planned work. It is distinct from a delay claim, which addresses lost time to Completion, and is usually proven using the measured mile method.
Delay is lost time to Completion or a Key Date, typically proven through programme analysis. Disruption is lost productivity or efficiency, typically proven through output records and the measured mile method.
The measured mile method compares actual labour or plant productivity during a period unaffected by the disrupting event against productivity during the period the disruption was in effect, on the same project. The difference in output rate quantifies the lost productivity and its cost.
They typically fail for lack of contemporaneous evidence. Without dated, detailed records of labour, plant and output for both impacted and unimpacted periods, there is no reliable measured mile baseline.
It works best on repetitive or linear work, such as cable-laying, pipe-laying, rail track or repeated housing units, where a genuinely comparable unimpacted period is likely to exist.
Disruption claims fail without a dated measured-mile baseline. Gather's QS AI Agent captures labour and output against every activity and date as your site diary is written.