Builders often rely on contractual extension of time (EOT) provisions to seek relief from liquidated damages or claims for breach of contracts when delay occurs. However, simply asserting a delay has occurred is not sufficient, the Courts and Tribunals require sound and well-documented evidence to support any EOT claim.

This article examines the types of evidence commonly used in EOT disputes, the legal standards they must meet, and best practices to strengthen your case in a dispute. 

Primary Forms of Supporting Evidence

To succeed in an EOT claim, builders must support their position with compelling evidence. This typically falls into three key categories:

  1. Documentation

Proper documentation is the main support of any EOT claim, the relevant documents can include:

  • site diaries and daily progress logs that track work activities, workforce, weather, and delays;
  • written correspondence between builder, owner, and subcontractors detailing events and decisions;
  • contract documents, including signed variations, construction programs, plans, and schedules; and
  • existing reports noting specific delays and their impact on the progress of the works.

Timely and consistent documentation provides a reliable chronology of events and strengthens credibility before a Court or Tribunal.

  1. Expert Evidence

When delays involve technical issues or schedule disruption, expert testimony may be required. Effective expert evidence includes:

  • reports prepared by qualified experts, such as construction schedulers, engineers, or quantity surveyors;
  • compliance with Court or Tribunal codes of conduct, acknowledging the expert’s duty to the Court; and
  • clear and detailed analysis that can demonstrate the delay and the specific causes are related and assesses its impact on the project timeline.

Vague or generic opinions that lack technical reasoning will carry limited weight and are often dismissed.

  1. Financial Records

Where EOT claims include financial compensation, such as liquidated damages,  additional costs incurred by the delay or increased labour rates, supporting financial documentations are essential:

  • bank statements, invoices, and receipts related to the delayed work;
  • schedules of quantified costs, including breakdowns for labour, equipment, and overhead; and
  • payment summaries or cash flow reports that demonstrate financial impact.

These records must align with the claim being made and be supported by credible accounting or project management systems.

Evidence Quality Requirements

Independent Evidence 

One of the key principles applied by courts is the preference for independent or external evidence. Internal communications, such as emails or internal memos, are less convincing unless supported by:

  • third-party correspondence;
  • official records (e.g., weather data, supplier communications); and
  • independent witness statements.

Documentary evidence must also be authenticated and clearly explained. Simply attaching documents without context or analysis is unlikely to succeed.

Expert Opinion Standards

Experts must demonstrate not only technical qualifications but also:

  • adherence to applicable conduct rules imposed by the tribunal or court;
  • detailed explanations of causation and consequence, not just conclusions;
  • relevance to the claims made, avoiding general industry commentary or unrelated opinions.

Experts should ensure their findings are tailored to the specific project and supported by objective analysis.

Key Considerations for Builders in EOT Claims

  1. Documentation Limitations:
  • unaffirmed oral statements will be treated with caution;
  • post-event reconstructions (e.g., compiling delay records after litigation begins) are often viewed with skepticism; and
  • documents in foreign languages must be translated and interpreted by qualified professionals.

Courts place the highest value on real-time records created during the project.

  1. Procedural Compliance

Evidence must be presented in accordance with legal procedure:

  • claims must be quantified and reconciled with the formal pleadings;
  • evidence must be submitted within the time the Court or Tribunal requires and in the format prescribed; and
  • when relying on oral testimony, transcript references and detailed citations are expected.

Failure to meet procedural obligations may result in evidence being excluded altogether.

  1. Best Practices

It is always the best practice to:

  • maintain contemporaneous records from project commencement;
  • engage qualified experts early to assess and document technical delays;
  • directly link all evidence to the delay being claimed; and
  • include external validation, such as supplier notices or meteorological data.

In summary, the success of an EOT claim depends not just on what happened during the project, but how well the builder can prove it. Builders who prepare detailed documentation, support claims with expert insight, and comply with procedural rules are far better positioned to protect their legal and financial interests.

Feel free to contact Damin Murdock at Leo Lawyers via our website, on (02) 8201 0051 or at office@leolawyers.com.au. Further, if you liked this article, please subscribe to our social media accounts.

DISCLAIMER: This is not legal advice and is general information only. You should not rely upon the information contained in this article and if you require specific legal advice, please contact us.