Passivhaus Affiliate

Standard Members

Cambridge Architectural Research



I am a specialised consultant established to promote the sustainable use of energy in non-domestic buildings and reduce the use of fossil fuels. I work with the public sector, commercial clients, property developers and charities. As a Carbon Trust accredited consultant I can often provide energy efficiency surveys free of charge (on behalf of the Carbon Trust). I offer a range of EPBD compliance services including Air Conditioning Inspections, non-domestic EPCs, and DECs. In addition I offer a range of energy consulting services.


CaSA Architects Ltd


CaSA Architects is an award-winning RIBA chartered design practice with a passion for original contemporary architecture using proven sustainable principles. We deliver carefully considered, bespoke solutions derived from a thorough understanding of our clients and tailored very specifically to them and the site. Quality is at the centre of our approach, inspiring and informing everything we do. Our work is principally in the private housing sector, but also includes education and community. We have experience applying Passivhaus principles to a range of building types, incorporating a fabric first approach. We have recently completed a pair of RIBA award winning community buildings in Hampshire built to Passivhaus standards. See our website for details


Cayford Design


Cayford Design. Certified Passivhaus Designers, creating inspiring environments and buildings for well-being, creativity and productivity. RIBA Chartered Practice


CBG Consultants



Cocreate Consulting


Cocreate are an accredited Passivhaus Certifier. We can help you achieve the Passivhaus standard and provide design advice to help architects, developers, and engineers improve the comfort and reduce the environmental impact of buildings over the long term - saving on operating and asset costs in the process. We help clients set the right specification, help contractors achieve the required standards, and offer training to professional teams to build understanding and improve decision making.




ColdProof is run by Eric Fewster, a Chartered Environmentalist and Certified Passive House Consultant. He specializes in using Passive House methodology and thermal bridge modelling to analyse and plan whole house retrofit projects for existing houses – this includes not only the energy analysis that enables homeowners to reach specific space heating demand or carbon emissions reduction targets, but also a practical plan of action which includes MVHR design, material specification, bill of quantities, economic analysis and work sequencing. This is all arrived at through several trial runs in which scenarios for improvements are honed according to the available budget - all done in consultation with the homeowner. He also can act as retrofit coordinator in certain cases.


Colin Smith & Judith Wilson: Architects


Specialising in contemporary architecture for twenty years, we work closely with our clients to create unique solutions for projects of all sizes, constraints and budgets, which are practical, functional and flexible. We believe in Passivhaus and eco home principles and employ them to produce environmentally aware, low energy, efficient houses and buildings that are a joy to use and enhance the lives of those living or working in them. Natural light and space are always exploited to the full, together with the considered use of natural, traditional and sustainable local materials and, above all, careful detailing to achieve beautiful modern designs.


Collective Architecture


Conker Conservation Ltd


Chartered building surveyors specialising in sustainable design, new-build, conversions, refurbishment and historic building conservation. A family business established in 1999 with experience in using modern and traditional methods of construction including rammed chalk, rammed earth, straw bales, timbrel vaulting (creating large span domes without formwork using clay tiles), super-insulated masonry and timber frame. Working with Passivhaus standard since 2005. We work mainly in the south east on residential, commercial and education projects. We are nuts about sustainability.


Constructive Individuals


Constructive Individuals is a York-based practice run by architect and Certified Passivhaus Designer Phil Bixby. The practice brings to projects over 25 years of experience in working with communities and individuals to enable them to decide, design and build. Past projects have included community self-build and self-help projects, sustainable social and individual housing, and extensive work with children and young people. We have worked as architects, project managers and training consultants, and aim to work WITH clients, rather than simply FOR them.


Cowan Eco Design

East Grinstead

Cowan Eco Design, part of Cowan Architects, is led by Mark Elton who has been responsible for numerous exemplary new-build and refurbishment, low-carbon projects over the last 20 years. Cowan Architects has established itself over 33 years with a reputation in residential care homes and housing, including a particular expertise in inclusive design. This brings a good correlation between these sectors and the health and well-being benefits of the Passivhaus approach. With London and Sussex offices, Cowan Eco Design covers the south of the UK with particular interests in residential and community projects, including retrofit to the EnerPHit standard.

Croft Farm Construction


Croft Farm Construction is a highly-skilled building contractor specialising in challenging projects on both traditional and contemporary buildings. We can offer a full turnkey solution for your project. Our involvement with Passivhaus comes from a desire to do things to the best of our ability; to seek out innovative solutions and to embrace new materials and methods. We are passionate about delivering customer satisfaction and engage fully with our clients to achieve this. We can see that Passivhaus is fast-becoming the gold standard for low energy living and we are fully committed to supporting and promoting the Passivhaus design concept.


CRS Future Build Ltd




Julian is a chartered building services engineer and Fellow of CIBSE with a specialism in sustainable/environmental building design, client design advice and low carbon master planning. He has 27 years of experience. Projects include the Royal Ontario Museum in Toronto, Tower Place in London, the Parkview Battersea Power Station scheme. He has recently completed his own certified Passivhaus in Hampshire and is a regular judge for the Construction News Awards and the RIBA sustainable building award. In 2016 he chaired the UKGBC task group – delivering Building Performance.


Cutland Consulting Limited

Milton Keynes

Cutland Consulting Limited provides strategic support for energy efficiency and sustainability, working from Board level right down to the technical ‘coalface’. Director Neil Cutland has a rare combination of technical knowledge and commercial experience, resulting in “a refreshing pragmatism”. Neil is one of the authors of the BREDEM model and the SAP, and in his previous roles at Inbuilt and BRE he was instrumental in bringing the Passivhaus standard to the UK. Neil subsequently served on the Passivhaus Trust Board.


CVC Direct Ltd


CVC Direct Ltd are distributors for Brink Climate Systems, the leading manufacturer in Europe of Passivhaus certified MVHR units with constant flow motors. This series of low energy MVHR units, several of which are available with an A+ ErP energy rating, offer a range of solutions including demand controlled ventilation. The Brink units are noted for the sophisticated design with a large range of operating parameters yet simple to install and commission as the air flows can be programmed with the digital controls. Years of experience means our designers can offer informed advice and innovative solutions for domestic ventilation installations. Brink MVHR units, when used in combination with our easy-to-install radial ducting, can ensure low energy, low noise, and no leak heat recovery ventilation systems. CVC Direct carry stock of both the Brink MVHR units and complete radial ducting systems for next day delivery.

CWG Choices Ltd


Manufacturers of Passivhaus certificated windows manufactured from the Award winning Kommerling/KBE System 88 range of PVCU profiles. Always at the forefront of innovation, the company is now manufacturing the high performance Residence 9 window. Whether it be a normal size casement window or a sliding door up to 10 metres long, we are able to help. In addition to Passivhaus certification the Company is also accredited Secure By Design. The highly successful Company manufactures windows and doors in either in PVCU or aluminium from factories in the East and West Midlands.


Cygnum Timber Frame Ltd


Established in 1996, Cygnum is a leading supplier of timber frame structures in the UK and Ireland. Cygnum’s Passive 350 building system received Passive House certification in December 2013. Some of our key technical staff are qualified Passive House designers and we have been the selected timber frame supplier on many Certified Passive House and near Passive House buildings including the award winning Oakmeadow school in Wolverhampton. More recently Cygnum have been awarded the contract to design supply and install the timber frame structure, glulam frame, cellulose insulation and airtightness layer for the high profile University of East Anglia Exemplary Low Carbon Building Project at Norwich Research Park.