Derek Pye

Derek is a Barrister at Law of Lincoln’s Inn and was called to the Bar following a career in the contractor, sub-contractor, client and consultancy sides of the construction and engineering industries. He has over thirty years’ experience in construction and engineering disputes and has been involved in over 400 cases since 1996. Derek is a Chartered Arbitrator, Chartered Quantity Surveyor, Registered Adjudicator, Accredited Mediator, Expert Determiner and Commercial Pilot. He has also appeared as Expert Witness on quantum and planning matters in the Technology and Construction Court.

Prior to being called to the Bar Derek has also had considerable previous international experience in contentious construction and engineering matters which has involved working in the USA, Canada, Germany, Switzerland, Belgium, Italy and the Middle East and, more recently, has also been consulted with regard to major contracts in China. He has also been involved with international and UK clients in successful negotiations for the equivalent of multi-million pound settlements particularly involving defects, contract delay, liquidated damages and international trade issues.


Derek’s involvement in arbitration includes over 80 Appointments as sole arbitrator including multi-million pound disputes with parties represented by Solicitor and Counsel. He has also acted as party representative/advocate. Recent personal arbitrator Appointments include:-

  • £7m claim on a hotel at Heathrow
  • Extension of time and £3m loss and expense and variations claim and £1m counterclaim on a commercial development in London.


Derek has been appointed as adjudicator in over 100 adjudications and has been involved in many more adjudications as party advisor/representative. He is a member of the RICS, CIArb, AICA and CEDR panels of adjudicators. Derek has also acted on various panels at the RICS to train, assess and re-assess the RICS panel of adjudicators. Recent adjudicator Appointments include:-

  • University loss and expense claim for £1.25m in Cambridge
  • Demolition contract at a university campus in London
  • £4m dispute on a commercial building contract
  • Mechanical services dispute on the O2 Arena
  • Electrical contract dispute on the Channel Tunnel Rail Link


Derek is an accredited mediator of the CIArb and accepts appointment as mediator in construction, engineering and general commercial disputes. Derek is a member of the Association of Northern Mediators. Recent mediation appointments include:-

  • Institution appointed mediator in three sports centre disputes
  • Party appointed mediator in a multi-storey car park dispute
  • Court appointed mediator in a residential construction dispute


Derek has appeared as advocate in:-

  • An $8m breach of covenant/warranty and fraud claim in arbitration in the USA involving international trade country of origin issues
  • A dispute in the UK over the interpretation of the overage provisions of a £5m development agreement.
  • An aviation related criminal trial.

Derek was also involved with Counsel in the successful appeal against an arbitrator’s award in the case of:- Newfield Construction Ltd v Tomlinson & Ano [2004] All ER (D) 280 Nov

Expert Determiner

Derek’s practice includes an increasing number of Expert Determinations particularly in the land/property development field. Recent disputes have included the awarding of a £14m construction contract and a multi-million pound overage provision.

Expert Witness

Derek has acted as witness of opinion in various cases in litigation and arbitration on matters of quantum and project planning. Reported Cases include:-

  • Motherwell Bridge Construction Limited (Trading as Motherwell Storage Tanks v Micafil Vakuumtechnik, Micafil; 81 Con. L.R. 44; [2002] All ER (D) 159 (Mar)
  • Ruttle Plant Hire Ltd v Secretary of State for the Environment, Food and Rural Affairs [2004] EWHC 2152 (TCC), 104 ConLR 110, [2005] All ER (D) 182 (Dec)


Derek is a multi-engine, instrument rated, commercial pilot.

He was the consultant construction expert in the BBC third series of Rogue Traders and made personal television appearances in two of the programmes in the series.

Areas of Expertise

  • Construction
  • Professional Negligence
  • Aviation Law

Reported Cases

  • Adjudicator in Allied P&L Ltd v Paradigm Housing Group Ltd [2009] EWHC 2890 (TCC) (17 November 2009); [2009] 47 EG 132, [2010] BLR 59
  • Adjudicator in OSC Building Services Ltd v Interior Dimensions Contracts Ltd [2009] EWHC 248 (TCC) (08 January 2009); [2009] CILL 2688, [2009]
  • Expert on behalf of Motherwell Bridge Ltd in Motherwell Bridge Construction Limited (Trading as Motherwell Storage Tanks v Micafil Vakuumtechnik, Micafil; 81 Con. L.R. 44; [2002] All ER (D) 159 (Mar)

Notable Cases

  • [Aviation Law] CAA v Pemberton (unreported)
    Acted as defence counsel in unsuccessful criminal prosecution of a commercial pilot under the Air Navigation Order 2005 in an alleged low flying incident over Manchester City Football Club’s Eastlands Stadium.


  • “Abatement, Set-off and Counterclaim- the art of how not to pay somebody” – University of Central Lancashire; MSc in Construction Law and Dispute Resolution.
  • “What is Evidence?” - University of Central Lancashire; MSc in Construction Law and Dispute Resolution.
  • “Managing Payment to Avoid Disputes” – RICS Avoiding and Resolving Disputes in Engineering and Construction Contracts Conference, London.
  • “Resolving Disputes in Construction; a Review of Recent Developments and a Perspective on Effective Dispute Resolution” – SCL/RICS/University of Manchester Conference.

Download CV

  • Call: 2008


  • Chartered Arbitrator (since 1998)

Professional Associations

  • Fellow of the Royal Institution of Chartered SurveyorsFellow of the Chartered Institute of ArbitratorsMember of the Academy of ExpertsCommercial Pilot (CPL/IR)


  • LLB(Hons), FRICS, FCIArb, MAE, Barrister at Law.

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T: 0113 245 5438
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