What is measured-mile analysis in a construction disruption claim?
Measured-mile analysis compares productivity on sufficiently similar work during less-affected and disrupted periods. It helps investigate lost productivity; it does not establish liability by itself.
By Jack Butler-Kettle · Updated
Guidance for England and Wales. Check the contract, amendments and facts that apply to your job.
The answer
The SCL Delay and Disruption Protocol discusses measured-mile analysis among disruption assessment methods. A comparison needs reliable outputs and resource records, with differences in conditions and other causes considered.
The figures below are invented to show the arithmetic. Check gang composition, work type, access, learning, overtime and the subcontractor's own performance before drawing conclusions. Explain adjustments and uncertainty. Where no fair comparison exists, choose a supportable alternative rather than manufacture a baseline.
Delay and disruption recovery tests the records behind the productivity comparison and separates the calculated difference from the amount attributable to a compensable event. Read the practical disruption problem for the evidence needed before valuing a claim.
Example
The facts
In a simplified illustration, a gang installs 100 identical units in 200 labour hours in one period and 80 units in 240 hours in another.
What happens
The baseline is 200 divided by 100: two labour hours per unit. The later rate is 240 divided by 80: three hours per unit.
At the assumed baseline, 80 units would use 160 hours. The observed difference is 240 minus 160: 80 hours.
At an illustrative supported labour cost of £30 per hour, the unadjusted difference is £2,400. Investigate comparability, other causes, entitlement and double counting before claiming it.
Illustrative productivity comparison
| Measure | Baseline | Affected period |
|---|---|---|
| Units installed | 100 | 80 |
| Labour hours | 200 | 240 |
| Hours per unit | 2 | 3 |
What this shows
The £2,400 is a difference to investigate, not an automatic recoverable loss. The result depends on whether the assumed comparison withstands scrutiny.
Sources
- Delay and Disruption Protocol, 2nd edition, February 2017. Society of Construction Law.