A celebration of Passivhaus


Passivhaus pioneers

It was in 2006 that I was given a book that would have a profound impact on both mine and Architype’s journey into Passivhaus design.

The book was ‘Sustainable architecture and urbanism: concepts, technologies, examples’ by Gauzin-Muller. It was a leaving gift from Architype after my two year’s work placement as an architectural assistant before going back to London Metropolitan University to complete my studies.

I had spent my time at Architype working on a variety of timber based early years projects that awakened my interest in simple design and robust construction and appealed to my training as both an engineer and architect.

The book ‘Sustainable architecture and urbanism: concepts, technologies,
’ by Gauzin-Muller has had a profound impact on my work

Hooked on Passivhaus

When I rejoined Architype in 2008, several senior members of the Architype team went on European visits to see some of the beautiful Passivhaus buildings, first developed by Professor Wolfgang Feist and fellow enthusiasts in 1991. Given the high-quality performance of the buildings and delighted occupiers, we were hooked. 

We felt the standard continued Architype’s tradition of highly insulated and low carbon-based beautiful buildings, based on a thorough understanding of construction – something we developed from our experience in self-build projects. This proven approach developed primarily around the benefit to the users of the spaces rather than any current in-fashion ‘aesthetics’.  Adding new rigours of calculations based on building physics, airtightness and build quality, with designs engineered for comfort and performance, this was so rare to see in traditional UK construction, both then and now. And even if an attempt was made at modelling performance, it was rarely robustly calculated – something that still blights the industry today with often up to five times mismatch of what will happen in theory compared to what happens in reality. In real life, this leads to overheating or cold, draughty spots, and huge amounts of wasted energy and carbon. What Passivhaus does is tightly insulate and provide an airtight barrier for buildings, optimising the power of the sun and drawing on natural heat generated by people and appliances. It is at heart a simple concept, based on nature, that demands a very thorough technical understanding of how a building works.

Pioneering Passivhaus

In 2010 Architype helped found the Passivhaus Trust in the UK. It is now more than ten years since ours and the UK’s first Passivhaus schools received certification, and 30 years after the standard was first developed in Europe. Since then, we have been at the forefront of pushing the boundaries of Passivhaus projects, designing, and overseeing construction of over 25 certified projects with a combined floor area of over 48,000m2 (TFA) and amounting to 198 homes and buildings.  We have delivered the UK’s largest Passivhaus residential schemes and largest non-residential Passivhaus buildings at the time, and the first of many innovative typologies such as Passivhaus archive buildings. 

Ten of the 25 are new build schools, two are certified EnerPHit (Passivhaus for retrofit) including an exemplar office for the University of Cambridge Institute for Sustainability Leadership which is saving £100,000 a year in energy bills. A zero operational carbon office and a primary school were built to the higher Passivhaus Plus standard, generating more energy than they consume. A further 17 projects have been designed to Passivhaus standard but are not yet certified or completed.

Many of our Passivhaus projects have achieved the best in-use energy performance monitored statistics of any UK buildings, far in excess of current best practice, and with numerous CISBE Building Performance of the Year Awards.

Carbon savings

Our modelling estimates demonstrate that these projects alone will have cumulatively saved approximately 6,750 tonnes of CO2e from operational or in-use emissions being emitted into the atmosphere since their certification (upto 2023), compared with those constructed to CIBSE Benchmarks. This results in over 75% savings in carbon emissions and significant financial savings to their owners. By 2030 our projects alone will have saved more than double current savings with some 15,500 tonnes of CO2e, equivalent to the annual emissions of some 2,218 people.

Using Passivhaus has delivered real carbon savings rather than spending money on dubious notional offsets or installing vast amounts of renewables to meet high energy demand to get close to net zero.

Now we are delivering more than 90% of our projects to the Passivhaus or EnerPHit standard, with an even larger pipeline of buildings in various stages of design. We are also providing expert advice on many larger scale projects through our Perform+ consultancy to advise clients, design teams and contractors on how to upskill and deliver high performance buildings fit for the future.

Chart showing carbon savings of Architype Passivhaus designs

What is Passivhaus?

Passivhaus is the gold standard for buildings, designed to ensure comfort of occupants, that also results in minimal energy and carbon demand.  Passivhaus adopts a whole-building approach with clear, measured targets, focused on high-quality construction and is certified through an exacting quality assurance process.  It was first developed 30 years ago in Europe and is now a common requirement of many municipalities and cities to ensure high performance and low energy usage.

In the beginning

Oak Meadow & Bushbury Primary Schools in Wolverhampton, which were jointly the first Passivhaus Schools in the UK (certified together with Montgomery Primary School by others) in 2012.  But our journey on the Passivhaus route dates back even further.  We recommended this standard of building to Camden Council, for the work on Fortune Green Play Scheme.  This was an amazing scheme that unfortunately never made it into reality, but our learnings were disseminated within the studio, and Bushbury and Oak Meadow were designed and delivered on site shortly after.  Camden Council came back to Passivhaus years later because the progressive approach was a great way to meet both their climate targets and reduce fuel poverty. This resulted in their housing schemes including Agar Grove – one of the largest regeneration sites in the UK – being delivered to Passivhaus, with Architype ensuring delivery of the targets for the first two phases (95 homes), and the project winning the NLA London Awards. 

We’ve worked hard to refine our approach – carrying out extensive post occupancy monitoring to constantly improve performance and demonstrate that Passivhaus buildings can be delivered at no extra cost and with significant reductions in running and maintenance costs.  We employ more than 24 Passivhaus Designers – quarter of our staff – more than any other practice, and with even more training planned.  For enhanced wellbeing benefits we’ve also maintained our focus on using breathable natural materials like timber and recycled newspaper insulation, instead of toxic plastic foam insulation.  

Oak Meadow primary school pioneered the Passivhaus standard in the UK

Passivhaus highlights 

Cumulative M2 of certified Passivhaus spaces by Architype

The Enterprise Centre, University of East Anglia – the largest non-domestic Passivhaus project at the time.  Winner of more than 30 awards including RIBA, ‘Guardian Sustainable Business Awards – Winner of Built Environment Category’ and featured in the COP26 Virtual Pavilion, one of 17 international exemplar buildings.  With six years of in-use energy data and DEC A ratings, this is still one of the best performing buildings in the UK.  This shows not only that Passivhaus can work with natural and low carbon construction materials, but integrated from the outset costs no more than standard builds, and delivers huge benefits in quality, comfort and fuel savings.

Imperial War Museum Paper Store – the important archive facility shows that simple construction strategies can result in brilliant performance and beautiful design.  The RIBA award-winning building has the best airtightness results on record, and the design of the high-performance thermal envelope significantly reduced the both the upfront and longer term costs associated with services required to maintain these important artifacts.

Harris Academy Sutton – The first and largest Passivhaus secondary school demonstrates that Passivhaus can be achieved in large scale buildings.  The RIBA award-winning beautiful design has been a beacon for empowering many more clients to adopt this standard for their buildings, after visiting and seeing the project either during construction or since completion.

The RIBA award-winning Paper Store at Duxford nestled among mature trees and the historic estate

The future

Reflecting on our long and fascinating Passivhaus journey, I’m excited about the range of transformational buildings in our studios’ pipelines, including even larger schools and many other building types.  Retrofit is going to become more and more important. The retrofit Entopia Building in Cambridge shows how a radical reduction of 75% lower heating demand and an 80% reduction in embodied carbon can be delivered. Our work with City of Edinburgh Council to develop an estate wide EnerPHit informed Retrofit Plan (EiRP) demonstrates how major estate owners can plan logically their journeys towards meeting their net zero targets.

As the climate catastrophe hurtles forward at an alarming pace, I hope this encourages you to demand higher performance and ultra low carbon Passivhaus buildings. We have demonstrated that it can be done and are pressing on with goals to make all new buildings hit this target, delivering buildings fit for the future.  If you or your organisation need help to understand how to get there, feel free to contact me on Linked In or through our London studio.