Passivhaus Affiliate

Standard Members

Membership of the Passivhaus Trust is open to anyone and does not necessarily imply achievement of the Passivhaus standard for buildings or components, or attainment of Passivhaus-related qualifications. Members of the Passivhaus Trust listed include architects, consultants, contractors, manufacturers and other industry professionals, as well as individuals, who support the work of the Trust in promoting the Standard in the UK.

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Warm: Low Energy Building Practice


Warm is an independent consultancy with the theoretical and practical understanding to bring pioneering low energy buildings from design to reality. WARM was set up in 2009 by father and daughter, Peter Warm and Sally Godber, with the aim of creating buildings with real energy savings. All our full-time staff are Certified Passivhaus Designers and our group includes chartered engineers & architectural technologists. Whilst there are only 8 of us our reach is significant in the Passivhaus World: WARM are the most prolific Passivhaus consultants and Certifiers in the UK, and winners of the 2019 CIBSE Award for Building Consultancy up to 100 employees as well as Passivhaus Designers of the UK’s best new building, winner of the RIBA Stirling prize 2019. Most Passivhaus projects in the UK have been either one-off self builds or low-rise estates for social housing, but we have been involved in nearly every Passivhaus school in the UK and the largest Passivhaus building. We also provide building services design, training, monitoring and anything else for low energy buildings that will improve the built environment. We strongly believe in disseminating information and manage the very successful Carbonlite training programme for designers and contractors as well as bespoke courses for clients.


Waxwing Energy

Little Birch

White Hill Design Studio LLP



Wickham Design Practice


Wickham Design Practice is based in London and is driven to produce high quality buildings and public spaces. The practices interests lie in helping its clients get the most from their site and in delivering well considered, beautiful places in which to live and work. We aim to produce low energy buildings that will age well and we deliver this through good design, working closely with clients, and the careful management of the procurement and construction process.


Will Rudd Davidson Ltd

Edinburgh and Glasgow

Will Rudd Davidson provides Civil, Structural and Conservation Engineering and Construction Consultant Services from Concept Design to Completion. We provide an exemplary service, and aim to exceed all expectations making the journey as seamless as possible. With main Offices in Edinburgh and Glasgow, we deliver Civil and Structural Engineering services across a wide spectrum of sectors throughout Scotland and across the UK. We are skilled at providing cost effective, practical and elegant solutions. We thrive on Problem Solving, providing robust solutions to challenging briefs. Whether in City Centre gap sites, Buildings at Risk, poor ground conditions or marginal plots of land, we will add value.


William Abbott Developments


William Abbott Developments is a developer and contractor based in the South West of England. We concentrate on building quality over quantity and leaving a positive mark in the communities we work with.


Williams Energy Design


Willmott Dixon


Willmott Dixon Group, founded in 1852, is the UK’s third largest privately-owned capital works, regeneration and support services company. The company’s family values and respect for people has seen the business achieve numerous accolades as one of the best places to work in construction. Willmott Dixon for the past three years has been the highest placed major contractor in the prestigious Sunday Times Best Companies to Work For list. Willmott Dixon’s internal sustainability consultancy, Re-Thinking, has a number of staff trained and qualified as Certified Passivhaus Designers and is actively promoting use of the approach across its three divisions.


WonKy: People Architecture Cities


WonKy is the partnership of Wai-Piu Wong and Lefkos Kyriacou (Certified Passivhaus Designer) with over 30 years collective experience in practice. The directors have taught extensively at universities and schools and been involved in architectural research and publications. WonKy considers the role of architecture and design in the context of broader societal issues to address problems and find opportunities to create projects that can deliver a significant impact. The practice undertakes research to inform and underpin their projects with an emphasis on the city and urban issues, with people first. The practice collaborates with artists, collectives, community groups and local authorities. WonKy places social and environmental sustainability at the core of the design process with a growing focus on urban ecologies.


Worcester Renewables Ltd



Wyephi Design & Consulting Ltd