About Us

Principal Building Consultant & Expert Witness

Mario Bournelis is the principal of City Wide Building Consultants, bringing extensive expertise in building defect analysis, expert witness services, and construction dispute resolution across Australia.

With over 15 years of tribunal and court experience, Mario has established himself as one of Australia’s most trusted building experts in the legal and construction sectors.

Professional Approach

Independence & Objectivity

  • Primary duty to the tribunal/court, not instructing party
  • Unbiased analysis based on technical evidence
  • Willingness to acknowledge alternative viewpoints
  • Modification of opinions when warranted by evidence

Communication Excellence

  • Technical matters explained in accessible language
  • Clear written reports with logical structure
  • Effective oral testimony and presentation
  • Responsive to questions from judicial officers
  • Professional interaction with legal representatives

Continuous Professional Development

  • Ongoing updates on building standards and codes
  • Awareness of current construction practices
  • Participation in professional networks
  • Understanding of evolving tribunal and court procedures

Contact Mario

  • Telephone

    0412 675 270

  • Email

    info@citywidebuilding.com.au

Professional Qualifications & Credentials

Building Licenses

  • Licensed Builder (NSW)
  • Licensed Building Supervisor (NSW)
  • Comprehensive building and construction qualifications
  • Substantial building experience across residential, commercial, and industrial sectors

Expert Witness Accreditation

  • 15+ years expert witness experience (2009–present)
  • Full compliance with NCAT Procedural Direction 3 “Expert Witnesses”
  • Acknowledged expert in NSW Civil and Administrative Tribunal proceedings
  • Accepted expert witness in NSW District Court matters
  • Experienced in Appeal Panel proceedings

Professional Memberships

  • NSW Master Builders Association (MBA) Member
  • Professional Indemnity Insurance maintained
  • Ongoing professional development in building standards and regulations
  • Member of the Resolution Institute of Australia.

Tribunal & Court Experience

Extensive Case History

Mario has provided expert evidence in numerous high-profile building disputes spanning over a decade, with documented cases from 2014 through 2025 including:

  • Consumer and Commercial Division matters
  • Home Building Act disputes
  • Building defect claims
  • Expert determination proceedings
  • Work order compliance matters
  • Complex building defect litigation
  • Multi-party construction disputes
  • Expert evidence in concurrent hearings
  • Joint expert reports and assessments
  • Appeal proceedings requiring technical expertise
  • Review of original tribunal decisions
  • Expert evidence on points of law and fact

Tribunals and courts have consistently preferred Mario’s evidence, with judicial officers noting:

  • His methodical approach to cost estimation using industry-standard references
  • Thorough site inspection procedures with comprehensive photographic documentation
  • Balanced and reasonable rectification recommendations
  • Expertise in applying Australian Standards to practical building scenarios

Expert Witness Services

Comprehensive Legal Support

Clear, independent expert evidence and reports to support building disputes in tribunal and court proceedings.

  • Detailed expert reports complying with NCAT Code of Conduct
  • Photographic documentation and site inspection records
  • Technical analysis with reference to applicable standards
  • Clear opinions on defects, causes, and rectification methods
  • Cost of rectification estimates
  • Preparation of comprehensive Scott Schedules
  • Joint Scott Schedules with opposing experts
  • Item-by-item defect analysis
  • Agreed and disputed items clearly identified
  • Cost comparisons and justifications
  • Participation in court-ordered expert conclaves
  • Collaborative approach with opposing experts
  • Focus on narrowing issues in dispute
  • Production of joint expert reports
  • Professional and constructive engagement
  • Extensive experience in concurrent evidence sessions
  • Clear and concise oral testimony
  • Technical explanations accessible to judicial officers
  • Professional interaction with opposing experts
  • Responsive to tribunal and court questions
  • Robust performance under cross-examination
  • Detailed knowledge of report contents and methodologies
  • Ability to explain technical matters clearly
  • Maintenance of professional demeanor
  • Credible and reliable witness presentation

Technical Expertise

Specialist Areas of Knowledge

Waterproofing & Wet Areas

  • AS3740 compliance assessment (waterproofing of domestic wet areas)
  • Membrane failure analysis and diagnostics
  • Moisture testing using calibrated equipment
  • Water penetration investigations
  • Shower and bathroom waterproofing defects
  • Balcony and external waterproofing systems

Structural Compliance

  • AS2870 analysis (Residential Slabs and Footings)
  • AS3700 assessment (Masonry Structures)
  • Foundation and structural defect analysis
  • Brick growth and expansion joint issues
  • Load-bearing capacity assessments
  • Compliance with National Construction Code (NCC)

Building Systems

  • AS/NZS 2589 (Gypsum Linings)
  • AS/NZS 3500 (Plumbing and Drainage)
  • Service installation compliance
  • Building envelope performance
  • Thermal and moisture control systems

Cost Estimation & Rectification

  • Rawlinson’s Construction Cost Guide expertise
  • Detailed scope of works development
  • Trade rate analysis and verification
  • Margin and contingency assessment
  • Preliminaries costing for remedial works
  • Geographic location adjustments

Building Code & Standards

  • Building Code of Australia (BCA/NCC) compliance
  • Environmental Planning and Assessment Act requirements
  • Home Building Act 1989 statutory warranties
  • Construction certificate and occupation certificate matters
  • Development consent compliance

Methodology & Approach

Site Inspection Procedures

Mario’s site inspections are thorough and methodical, incorporating:

  • Comprehensive visual inspections of all accessible areas
  • Moisture meter testing to adjacent walls and surfaces
  • Identification of water penetration points and patterns
  • Photographic documentation with detailed annotations
  • Measurement and recording of defect locations
  • Assessment of compliance with building plans and standards

Technical Assessment Tools

  • Moisture meters for waterproofing analysis (zero readings indicating no membrane failure)
  • Australian Standards reference (AS2870, AS3700, AS3740, AS/NZS 2589, AS/NZS 3500)
  • Building Code of Australia/NCC compliance verification
  • Rawlinson’s Construction Cost Guide for accurate cost estimation
  • Industry best practices and methodologies
  • Photographic and measurement equipment

Cost Estimation Approach

Mario’s cost estimates are consistently recognised by tribunals for their accuracy and reasonableness:

  • Use of current Rawlinson’s Construction Cost Guide data
  • Verification against actual trade rates and quotations
  • Geographic location considerations
  • Inclusion of preliminaries for remedial works (typically 5–8%)
  • Appropriate margins for builder’s overheads
  • GST considerations
  • Realistic timeframes for completion

Professional Standards

  • Compliance with NCAT Expert Witness Code of Conduct
  • Independence and objectivity in all matters
  • Duty to the tribunal/court over instructing party
  • Acknowledgment of limitations in expertise
  • Willingness to modify opinions based on new evidence
  • Clear distinction between facts and opinions

Key Technical Specializations

Waterproofing Defect Analysis

Mario has particular expertise in identifying and assessing waterproofing failures, including:

  • Shower recess and floor waste defects
  • Puddle flange installation issues
  • Membrane termination and continuity
  • Water ingress investigations
  • Balcony and external waterproofing
  • Wet area compliance with AS3740

Structural & Masonry Issues

  • Foundation adequacy under AS2870
  • Brick growth and expansion joint requirements (AS3700)
  • Structural certification verification
  • Load-bearing capacity assessments
  • Compliance with NCC structural performance requirements
  • Weephole installation and cavity wall construction

Construction Process Understanding

  • Preliminary works (site surveys, set-out)
  • Construction certificate triggering events
  • Building inspection stages
  • Compliance certification requirements
  • Practical completion standards
  • Defects liability period obligations

Why Engage Mario Bournelis

  • Proven Track Record

    • 15+ years of successful expert witness engagements
    • Extensive case history across NCAT, District Court, and Appeal Panel
    • Consistent tribunal acceptance of evidence and methodologies
    • National reputation for technical excellence and professional integrity

  • Technical Depth

    • Licensed builder with practical construction experience
    • Comprehensive knowledge of Australian Standards
    • Industry-standard cost estimation expertise (Rawlinson’s)
    • Understanding of NCC/BCA compliance requirements

  • Legal Process Understanding

    • Familiarity with NCAT procedures and requirements
    • Experience with Scott Schedules and joint expert reports
    • Skilled in concurrent evidence and expert conclaves
    • Professional performance under cross-examination

  • Client Service

    • Responsive and timely communication
    • Clear fee structures and transparent pricing
    • Urgent matter accommodation where possible
    • Comprehensive written reports with photographic evidence
    • Available for conferences and consultations

Industry Recognition

Tribunal Preferences

Across multiple cases, NCAT members and District Court judges have preferred Mario’s evidence over opposing experts, noting:

“Mr Bournelis relied upon Rawlinsons and his own experience, and his rates are close to the rates set out in Rawlinsons. The database relied on in the compilation of Rawlinsons is superior to the information a single expert could gather.” – District Court of NSW, 2025

“The Tribunal is not persuaded that the qualifications of [the opposing expert] are to be preferred to those of Mr Bournelis in assessing a proper and reasonable scope of works for rectification.” – NCAT, 2017

“The Tribunal prefers the opinion of Mr Bournelis that a complete strip out is not necessary, and further that to adopt such course of rectification would be an excessive response.” – NCAT, 2017

Collaborative Expertise

Mario works effectively with other technical experts, including:

  • Structural engineers
  • Specialist waterproofing consultants
  • Ceramic science professionals
  • Surveyors and certifiers
  • Other building consultants

Case Experience Highlights

While maintaining client confidentiality, Mario has been involved in matters concerning:

  • Residential Building Defects: Waterproofing failures, structural issues, brick growth, rendering defects, tiling non-compliance
  • Commercial Projects: Office buildings, retail premises, mixed-use developments
  • Home Building Act Disputes: Statutory warranty claims, major defects, rectification cost disputes
  • Work Order Compliance: Assessment of completed rectification works
  • Expert Determination: Alternative dispute resolution as independent expert
  • Cost Disputes: Quantum of damages, reasonable cost of rectification

Case Value Range

From modest residential claims to complex multi-party disputes exceeding $100,000
Success Rate: High acceptance of evidence and recommendations by tribunals and courts

Contact Mario Bournelis

For expert witness services, building inspections, or expert determination:

City Wide Building Consultants
Sydney NSW

Phone: 0412 675 270

Email: info@citywidebuilding.com.au

Urgent Matters

For matters with tribunal or court deadlines, please contact us immediately. We prioritize urgent instructions where expedited reporting is required.

Legal Professional Enquiries

We work with solicitors, barristers, and legal representatives across Australia. Please contact us to discuss your expert witness requirements, including:

  • Initial case assessment
  • Preliminary advice on technical matters
  • Formal expert report engagement
  • Scott Schedule preparation
  • Attendance at expert conclaves
  • Court/tribunal attendance

Commitment to Excellence

Mario Bournelis and City Wide Building Consultants are committed to providing the highest standard of expert witness services, combining technical expertise, legal process understanding, and professional integrity. Our goal is to assist tribunals and courts in reaching just and technically sound decisions through clear, accurate, and independent expert evidence.

Whether you require expert testimony in complex building disputes, detailed defect analysis, or cost of rectification assessments, Mario brings the experience, qualifications, and professional approach necessary to support the legal process effectively.

City Wide Building Consultants – Delivering professional building inspection services backed by tribunal-accepted expertise since 2009.

National Service Delivery

City Wide Building Consultants provides expert services across all major Australian cities:

Sydney | Melbourne | Brisbane | Canberra | Adelaide | Hobart | Perth

We understand regional variations in building practices and standards while maintaining consistent application of national codes and Australian Standards. Our national presence allows us to service clients regardless of property location, ensuring the same high-quality expertise and professional standards across Australia.

Professional Indemnity Insurance

City Wide Building Consultants maintains comprehensive professional indemnity insurance, providing clients and courts with confidence in our professional standards and accountability.