Passivhaus Affiliate

Members: Certifiers


Members listed in this category have been internationally accredited by the Passive House Institute (PHI) to certify Passive House buildings, EnerPHit retrofits and Low Energy Buildings anywhere in the world on behalf of the Passive House Institute and in accordance with their criteria. For the full international list of accredited certifiers, please check the Passive House Institute's comprehensive listing.

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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.


Greengauge Building Energy Consultants

Bradford on Avon

Greengauge is a building & engineering consultancy specialising in sustainable, low energy design. Physics and thermal dynamics drive our philosophy and we approach our projects Fabric First to deliver buildings that are comfortable, simple and efficient. We work on new-build and existing buildings optimising insulation, fenestration and thermal bridging to produce robust buildings with minimal systems necessary to maintain comfort. We are completely independent of manufacturers, products and installers so can provide objective advice, backed up by a suite of software tools and research.


Max Fordham LLP

London, Cambridge, Edinburgh, Bristol and Manchester

Max Fordham is an environmental building services engineering consultancy. For over 50 years, they have engineered energy, air, light and sound to bring buildings to life. From their five UK offices they have worked with the worlds leading architects on some of the worlds greatest buildings. Max Fordhams Passivhaus portfolio includes award-winning exemplars of sustainable design and a diverse mix of beautifully engineered buildings. Having worked on some of the largest and tallest Passivhaus projects in the UK, they are comfortable delivering at any scale. They have a team of certified Passivhaus Consultants and Designers and are experienced in providing the design/planning service.


Beyond Carbon Associates Ltd


Beyond Carbon is a design and engineering consultancy founded by Dr. Joel Callow. We are passionate about decarbonising the built environment, as well as creating beautiful spaces and places in which people thrive. Beyond Carbon are Passivhaus designers and consultants for large-scale buildings, sites and masterplans. We engineer an excellent, beyond-zero-carbon built environment using the Passivhaus Standard as a key tool. Allied to this, we use whole-life-carbon tools to calculate, minimise and optimise total carbon, including the carbon emissions embodied in construction. We encourage our clients to consider low energy retrofit where possible, and also engage in Passivhaus design on new construction projects where retrofit isn’t viable.




Etude are a team of sustainability engineers specialising in low energy building design and environmental assessments. We are Passivhaus Certifiers and can help you achieve the Passivhaus standard.


Mead Ltd


MEAD was founded by Kym Mead in 2014 as an independent consultancy specialising in ‘low-energy’ buildings, offering impartial advice to industry professionals and aspiring self-builders. Our aim is to reduce the energy demand of domestic and non-domestic buildings, whilst also providing excellent indoor air quality and comfort levels. Our approach is to cost effectively improve the building fabric and services whilst using the local environment to enhance the comfort levels throughout the year.


MosArt Ltd

Wicklow, Ireland


QODA Consulting



SE3D / bePHit


SE3D are a design-led team of Passivhaus consultants, architects and designers. As bePHit, the team also offers accredited Passivhaus certification services. We work collaboratively to help create healthy, human centred, high performance environments for our clients. We believe design is about people and the living and working environments we create for us and future generations to come. It is about how our environment impacts on us and how we impact on the environment - in other words ‘socio-ecological design’. As Passivhaus experts we are involved with the delivery of more than 500 Passivhaus dwellings, offices, schools, higher education, care and public pool and leisure facilities.




Spruce is a specialist consultancy providing expert advice on retrofitting homes to make them more energy efficient and comfortable. We also provide Passivhaus Consultancy and Certification for residential and small commercial projects. ​We are led by Dr Sarah Price, a highly experienced building physicist and Passivhaus Consultant with a keen interest in all things retrofit. Our goal is to inspire and accelerate best-practice, energy-efficient retrofit in the UK so that our homes are healthy to live in and affordable to run and maintain.


ZE Passivhaus Services Ltd


Zero Energy is an international engineering practice specialising in Passivhaus buildings. The company was initially set up in 2011 in the Scottish Highlands by Dr Jesus Menendez. At Zero Energy, we use advanced building physics knowledge in the building industry to help our clients to achieve low-energy and healthy buildings.We are an accredited Passivhaus course provider using the official and updated PHI material for Passivhaus Designers, Passivhaus Tradespeople and the new Passivhaus PHPP Expert course. We have been Passivhaus building certifiers since 2017 for any Passive House project around the world. To date, we have been involved in many certified projects around the world. We also undertake third-party non-destructive testing, such as Blower door tests, extinguishing gas retention time tests, infrared thermography, in situ U-value measurement for the building envelope or compensated airflow measurement in ventilation systems using balometers.