Johanne Twentyman

Johanne Twentyman

Architect | Expert Witness

– BA (Hons) Architecture
– Gradute Dipolma in Architecture
– Postgraduate Diploma in Architectural practice
– Chartered Member of the RIBA

Johanne is a practicing RIBA Chartered Architect working in the UK. Since qualifying in 2009, she has gained extensive experience in the design of Acute and Primary Healthcare facilities throughout London and the South East which has given her an in-depth understanding of the requirements for effective and efficient delivery of care, and also from a disabled user’s perspective of receiving care.

Johanne has developed particular expertise within emergency medicine, rehabilitation and physiotherapy and mental healthcare. This specialism forms the foundation of her expertise as a Healthcare Architect which is considered to be fundamental in supporting her role as an Expert Witness in the field of accommodation for disabled people. She is proficient in the provision of environments that are compliant with Building Regulations and adhere to DDA (Disability Discrimination Act) and Equality Act standards and has a thorough knowledge of healthcare design guidance including documentation published by the Department of Health’s Healthcare Building Notes (HBN) and Healthcare Technical Memoranda (HTM).

As a chartered member of the Royal Institute of British Architects, Johanne practises in accordance with the code of professional conduct and maintains her requirement for continuing professional development through attendance of seminars and conferences worldwide with a particular focus on accessible design, healthcare design and best architectural practice.


Johanne’s architectural experience has provided her with an expertise in the provision of accessible accommodation for people with cognitive, behavioural, physical, and visual impairments.

Johanne accepts expert witness instructions for accommodation needs in medical negligence and personal injury claims.

She assesses the suitability of the current domestic situation of claimants reporting her recommendations for their future accommodation needs. She has gained particular expertise working with people who present with, inter alia:

  • Spinal Injuries
  • Limb amputations
  • Hypoxic Brain Injury
  • Wrongful birth
  • Infant claims involving cerebral palsy
  • Cauda Equina Syndrome

Johanne is employed at Cowan Architects in the position of Healthcare Architect. In addition to her architectural duties she undertakes the preparation of accommodation reports on behalf of both Claimant and Defendant, reporting on cases within the United Kingdom. She currently undertakes reports in a ratio of approximately 50% Claimant and 50% Defendant