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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i3PT Certification


Iain Clavadetscher


Iain Clavadetscher works with CHMRP Architects work in close collaboration with his clients to create bespoke solutions developed from an appreciation of physical and historical context. The success at which this is achieved is borne out by the fact that over 80% of his work is derived from repeat commissions.

Ian Van Duivenbode


Ian Waters Design Ltd

St Ives



IF_DO is a multi-award-winning RIBA chartered practice, founded in 2014 by three good friends excited by the possibility of doing things differently. We believe architecture has the power to improve lives and make communities happier and stronger. We have a knack for building relationships, exceeding expectations and delivering projects with people at their heart. Our work is developed following careful analysis of context, informing a contemporary architectural response that is sensitive and appropriate to its place. Our expertise ranges from one-off new build homes to retrofit and adaptive reuse of commercial and civic buildings. For every scale of project, IF_DO always seeks to deliver broader social and environmental benefits—working with our clients to make their projects do more.


Individual Member


Individual member


Inside Outside Engineering Ltd


We design the mechanical and electrical services to make the *Inside* of the building work best. We feel that this starts with understanding the local climate, the *Outside*, and how the shell of the building acts as a filter to that environment. We advise on how to optimise the building form and design from the get-go. The best results can be achieved when we bring the whole scheme together to create comfortable & desirable spaces for living.


Insulated Floors Ltd



Intelligent Membranes & Windows


Intelligent membranes are liquid applied membrane suppliers and installers. Our Passive Purple is an airtight intelligent liquid vapour control that gets 0.03 ach on any substrate it is adhered to. It is BBA CERTIFIED and Passivhaus Certified. Passive Purple External is our waterproof facade membrane that is vapour open. We also have our own range of Passivhaus certified windows called Artemis.