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Expert Profile

Mark Wheeler

Mark Wheeler

Head of Diales - Quantum and Technical Expert

LLB (Hons)
Accredited Mediator
Society of Construction Law
Adjudication Society
Various NEC lectures, delivered nationally, dealing with disruption and acceleration
Mechanical and Electrical
Process & Industrial
Asia Pacific
Middle East
United Kingdom


  • Chartered Quantity Surveyor
  • Building Services Engineer
  • 40 years’ industry experience
  • Specialist in evaluation of loss and expense claims
  • Advises on practical application of NEC3 and NEC4
  • Accredited practising mediator (ADR Group)
  • Cross-examined in both Court and Arbitration


Mark has 40 years’ engineering experience within the construction industry. He trained as a mechanical and electrical engineer, with a firm of specialist contractors, before moving into construction and property development.

Undertaking a wide range of building services installations in commercial buildings, on both a pre-designed, and design and build basis, Mark gained site experience in office developments, industrial projects, and a number of schools and hospitals. This has involved work on a wide range of contracts including JCT; PPC2000; BE Collaborative; FIDIC; and the NEC3 form, with which he has worked extensively.

Sector experience includes building, including hospitals, schools and colleges, power stations, including nuclear, coal and gas fired; and a number of major infrastructure projects. Mark has provided advice on the correct application of the NEC3 form of contract, including highways and remediation projects.

Mark has acted as an Expert Witness in both technical mechanical and electrical (M&E) matters and quantum disputes. He has also been instructed as expert in NEC3 disputes, from both a project management and quantum perspective.

His quantum claims experience includes those relating to additional payment for variations, re-measurement, damages, disruption, prolongation, and increased costs. Particular areas of expertise include issues such as: re-rating of billed items, valuation of disruption, preliminaries thickening, head office overheads, site overheads, and plant depreciation.

Mark has practiced as a project manager and has completed a challenging project for one of the world’s leading artists, delivering advanced new art storage, gallery space and studio production facilities.

This expert has the following cross-examination experience:

  • The Technology and Construction Court
  • High Court Action
  • International Arbitration
  • Domestic Arbitration
  • Adjudication/Mediation

This expert has recently been instructed by:

  • Ashfords
  • Carillion
  • Clarke Willmott
  • DAC Beachcroft
  • Fenwick Elliott
  • Freeth Cartwright
  • Lyons Davison
  • Mogers
  • Pinsent Masons
  • Shearman & Sterling LLP

“I prefer the evidence of Mr Wheeler to that of Mr XXX in all respects …” High Court Judge

WWL says:

“Mark Wheeler sits among the foremost construction experts in the market, where he receives widespread endorsements for his strong track record in quantum disputes and expertise in mechanical and electrical matters.”

Mark is recognised by Who’s Who Legal as a Global Leader in Construction Expert Witnesses 2023, and in Consulting Experts – Construction – Quantum Delay & Technical 2023.