Delay, disruption and extra cost: the differences
Finishing later, working less efficiently and spending more are different problems. Understanding the distinction helps you explain what happened on your package.
By Jack Butler-Kettle · Updated
Guidance for England and Wales. Check the contract, amendments and facts that apply to your job.
The short answer
Delay concerns time; disruption concerns how efficiently work is performed. Their financial consequences need separate explanation and evidence. An extension of time does not automatically establish a right to additional money.
Describe the effect on your work
Identify the affected activity and event. Explain whether work started later, lasted longer, changed sequence or needed additional resources.
A delayed activity may not delay completion. Disrupted work may finish on time through extra labour or changed methods.
The SCL Delay and Disruption Protocol offers professional guidance on assessing these matters. It is not legislation and does not replace your subcontract.
Check time entitlement separately
Keep the agreed programme, revisions and progress records. Explain how the event affected the work that controls your completion date.
Identify relevant notices and update obligations. Do not wait for the full financial effect before checking a notice deadline.
Separate events attributable to different parties and periods that overlap. Complex causation or competing delays may require specialist programme analysis.
Build the financial explanation
Identify the contractual basis for additional payment before calculating it. Record actual additional site costs and explain why the event caused them.
Keep resource and output information if productivity changed. Comparing totals without allowing for different conditions can give a misleading result.
The head office overheads calculator compares formulas. It does not establish that overheads were lost or that a period is compensable.
Keep records that connect event and effect
Save daily labour and plant records, work locations, access restrictions, instructions, photos, deliveries and contemporaneous programme updates.
Use an event chronology linking each event to affected activities and supporting files. Explain gaps rather than inventing missing records.
See claims records and evidence for a practical structure. This is general learning for UK subcontractors. Check your governing law, contract form and amendments. Statutory procedures differ across England, Wales, Scotland and Northern Ireland.
Example
Fictional example, not a client result. Figures are simplified to explain the point.
The facts
A mechanical subcontractor works in smaller areas than planned because preceding works are incomplete. It adds labour and still meets its completion date.
What happens
It records available work areas and daily labour against output.
It compares the working conditions with its original plan and identifies other possible causes of reduced output.
It checks its contractual route and explains any claimed additional cost separately from completion delay.
What this shows
The example concerns possible disruption without an assumed extension of time. Additional labour alone does not prove recoverable loss.
Sources
- Delay and Disruption Protocol, 2nd edition, February 2017. Society of Construction Law.