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Expert Profile

Simon Hay

Simon Hay

Technical Expert


Dip Arch.
Dip Arb.

Memberships & Associations


Contract Experience


Presentations & Training

Simon is recognised as a leading expert in masonry and has lectured on brickwork at post graduate level at Kingston, Loughborough, and The Architectural Association Universities.
Recent presentations include CPD approved presentations on damp proofing; Timber treatment and basement design.



Regional Experience

Middle East
United Kingdom

Cross-Examination Experience



  • Chartered Architect
  • Over 35 years’ private practice and cladding products manufacturing experience in a wide range of building sectors
  • Experience in architectural, external envelope and contractual disputes
  • Wide range of international and specialist experience



Simon is an experienced Chartered Architect and Expert Witness. Projects include HQ office buildings, schools, hospitals, retail, residential and industrial projects. Simon has been appointed on a variety of disputes, producing CPR 35 reports focused on the negligence of contractors; sub-contractors, landlords, and the design team.

In addition to being a Fellow of the Chartered Institute of Arbitrators, Simon is a Member of; the Council for the International Masonry Society, the Academy of Experts, the Society of Construction Law, the Cement and Concrete Association, the Craft Committee Tylers and the Bricklayers Livery Company. Simon is also named on the RIBA’s Register of Experts and he is a Certified Mediator, registered with Clerksroom.

Simon has led design teams from refurbishment of important Grade 1 listed buildings for schools such as Woodhall Park; to Green Building of the Year, Lindford Wood East, with ECD, exemplifying the best environmental construction and energy saving measures. He has designed and supervised major buildings including schools and social services day centres and, has an understanding of both public and private commissions.

He has specific experience in research and development including the application of standards and conformity to industry requirements. Simon approaches disputes with in-depth technical knowledge of construction types, building construction and contractual obligations. Simon has assisted on a number of Stirling prize listed building contenders with detail advice, including the 2016 winner Damien Hirst’s Newport Street Gallery.

Simon was involved as the Design Director at Guildform in the first unitised cladding instillation in the UK in docklands, and also helped clad The Paragon the largest high rise modular prefabricated units in Europe for Berkley First in West London. Prior to this, Simon was the Company Architect at Eternit UK the leading roofing and cladding manufacturer. Simon is therefore able to advise on the external envelope with significant Expert knowledge

He led the Brick Development Association for both Standards and technical work as the CEO for five years. His practical and technical approach which encompasses best practise and knowledge of standards has assisted in the resolution of disputes. He is a leading expert on brickwork.

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:

  • Birketts Solicitors
  • Chorus Group
  • Collyer Bristow
  • Hallmark Solicitors
  • Lambeth Council
  • Land Securities Group PLC
  • Judge and Preistly LLP
  • Patron Capital Ltd.
  • Stephenson’s Solicitors
  • Wong Partnership LLP

Hallmark solicitors thanked Simon for ‘helpful assistance in the case’. RC Brickwork noted Simon’s Expert assistance enabled a settlement to be achieved, which otherwise would have resulted in Court Action.