By: Luka Dickson

In the realm of legal disputes within the construction industry, few roles are as vital as that of a construction expert witness. These professionals are entrusted with providing courts and tribunals with independent, well-informed opinions on intricate construction matters.

Understanding Construction Expert Witnesses

At its core, a construction expert witness is a qualified individual engaged in providing impartial and expert insights in legal construction disputes, whether in a courtroom or tribunal setting. These experts possess extensive technical knowledge of the construction industry, particularly in areas such as cost estimation, construction processes, and legal standards. To ensure their credibility, they must be registered as quantity surveyors by AIQS (Australian Institute Of Quantity Surveyors) or a comparative body, signifying their proficiency in accurately assessing construction costs.

Resolving Construction Disputes

Construction disputes frequently revolve around financial matters, encompassing disagreements over incomplete work, substandard quality, or disputes related to costs. This is precisely where the expertise of a quantity surveyor expert witness becomes invaluable. These professionals excel in cost estimation services, enabling them to accurately assess costs associated with construction processes, thereby facilitating dispute resolution.

To navigate the complexities of a construction dispute, an expert witness creates a comprehensive report that delineates the issues at hand, facts, and the calculations underpinning their expert opinion. These reports also encompass detailed cost assessments and recommendations, providing the tribunal or court with a lucid understanding of how the expert witness arrived at their conclusion.

Responsibilities and Qualifications

The role of a construction expert witness entails substantial responsibilities. In addition to possessing expertise in the construction field, these individuals must boast specific experience related to the subject of the dispute. According to The Evidence Act, Section 76 – The Opinion Rule – “If a person has specialised knowledge based on the personal training, study or experience, the Opinion Rule does not apply to evidence of an opinion of that person that is wholly or substantially based on that knowledge.” A court can reject evidence the witness provides if there is sufficient reasoning that the expert is not qualified enough to provide accurate information on the dispute.

Furthermore, expert witnesses adhere to a strict code of conduct. They must provide “specialised knowledge” in their reports and remain impartial throughout the proceedings. Their role is not to advocate for the party that hires them but to provide an objective assessment grounded in their expertise.

Avoiding Conflicts of Interest

Maintaining impartiality is paramount in construction disputes. Expert witnesses must have no “financial or tangible connection” with either party involved in the dispute. The regulations concerning conflicts of interest are stringent, and any undisclosed connections may result in the rejection of evidence. Potential conflicts of interest should be disclosed promptly to all relevant parties.

Adherence to Expert Witness Codes

Construction expert witnesses operate under a strict, publicly available code of conduct. This code underscores their role in serving the court rather than any hiring party. It ensures that their impartiality is evident in their reports and interactions. Expert witnesses are often required to provide evidence of their impartiality and their process of arriving at conclusions.

Construction Expert Witness Reports

An expert witness’s report is a critical component of their role in a construction dispute. These reports must adhere to specific rules and requirements:

  • The report should be easily understood by individuals without comprehensive knowledge of construction claims or quantity surveying.
  • It must include the qualifications and CV of the surveyor, the brief provided by the legal team, and the expert witness code.
  • Chronological documentation, calculations, and tests should be included to provide a complete picture.
  • The report should address the issues examined. These include key facts and documents, inspections and tests conducted, calculations used, and a comparison with other expert opinions.
  • Finally, it should provide a summary and conclusion that encapsulate the expert witness’s findings.

Multiple Expert Witnesses and Conclaves

In complex construction claims, multiple expert witnesses may be involved, each with their own interpretations and opinions. These experts often engage in discussions known as conclaves, which take place outside the courtroom, supervised by an arbitrator or judge. Conclaves allow experts to discuss areas of agreement and disagreement, potentially providing differing perspectives.


Expert witnesses are often subjected to cross-examination during tribunal hearings. This process involves questions from the judge and the involved parties, challenging the expert’s knowledge and opinions. Expert witnesses must be well-prepared to explain their assessments and opinions in detail.

Estimating services in Australia

At Accent Estimating, our team of expert, registered quantity surveyors pride ourselves on providing reliable and detailed budgetary estimating services on construction projects. Our experienced team assures accurate information and support to all builders and contractors. We believe all parties involved deserve a fair deal, and a fast, streamlined development process.  

If you would like to find out more about our estimating services available in Sydney, Melbourne, Perth and Brisbane, call us on 0413 953 869 or fill out the contact form on our website.