The AECB's long march to Passivhaus

The story of how the AECB (the Association of Environmentally Conscious Builders) changed from being fringe sustainable organisation to Britain's prime Passivhaus promoters told in full

On a warm mid-October day in 2010, Chris Huhne, the new coalition Government’s Energy and Environment minister strode purposefully towards the lectern to give a speech in North London’s Islington Town Hall. The hall was packed, and the event’s audience, the first Passivhaus conference in Britain, waited to hear what the minister had to say. Later the lines were analysed and deciphered for clues to ‘the greenest Government ever’ commitment to decarbonising the country’s building stock. A key line referred to the event as “a watershed moment,” in which he’d “like to see every new home” reach the Passivhaus standard. It was quite a journey for the continental Passivhaus approach to building, which just three and a half years earlier hardly any in Britain had heard of.

A year on from the 2010 Passivhaus conference, what high hopes were attached to the Government’s commitment to decarbonise Britain’s entire residential building stock, have been fading by the month. Yet as 2011’s UK Passivhaus conference underlined, alongside acknowledgment of the Government’s watering down the regulatory guidelines on carbon and energy reduction amidst very choppy economic waters, a sense of confidence about Passivhaus’s future in Britain was palpable. As a two-day event the conference had doubled in size, while also moving to a more established venue, the Barbican arts complex in the city of London. Turn out was high, approaching 300 delegates, although there were no big catches of the likes of Huhne. In place, in terms of the wider Governmental and policy dimension, sustainableBYdesign’s Lynne Sullivan provided the view from the ministerial advisory committee’s, Sullivan outlining how she believed that Passivhaus standards would be introduced when the next wave of sustainable building regulation, (called Part L) kick in, in 2013, while also reflecting that given Britain has the worst air qualities in all Europe, support may also come through the health and well being agenda.

2011's UK Passivhaus conference
Photo's Abraham Garcia and UK Passivhaus Trust
2011's UK Passivhaus conference
Photo's Abraham Garcia and UK Passivhaus Trust
If Sullivan’s talk provided an insight into policy processes close to the technocratic heart of Government, the conference whole profiled the shifting shape of Passivhaus in the UK, with a significant number of businesses represented, adding to the perception that Passivhaus is continuing its journey in from the margins and establishing itself closer to the heart of the construction industry. Jon Bootland, (director of the UK Passivhaus Trust, the body launched the previous year as an umbrella organisation to promote the building approach in the UK, spoke for quite a few when he argued that Passivhaus is presently transitioning from it’s pioneering to a more mainstream position in the UK building sector. While there are only a score of certified projects at present, there would be seventy within six months, he predicted, based on knowledge of projects that had passed planning. This could multiply quickly, Bootland added, with perhaps, two hundred within two or three years. He pointed to how established companies are now involved, though also the presence of affordable housing developers at the conference, with a number of larger scale projects either on site or in preparation. Others said much the same, though were more cautious about on the ground uptake, the line being that there was ‘a lot of interest’ even though, they acknowledged when pushed, that interest didn’t necessarily translate into solid projects.

This exponential curve in momentum and practical take-up is also apparent in the growth in training courses, around a hundred architects, engineers and other building types have qualified as Passivhaus designers from one of the four Passivhaus accreditation courses available since the first was run at Strathclyde University in association with the Scottish Passivhaus Centre only two years ago. Such take up as much as the ministerial name-drop are signs and acknowledgement that Passivhaus is becoming known as effective in producing the very low energy results that are at the heart of its existence. This growing acceptance, although still pretty minuscule – Bootland talked of there being maybe 500 people all told involved in Passivhaus in the UK - when compared to the building sector, adds to the picture that the migration of Passivhaus from its central European origins to fully fledged UK movement is now well developed. It has followed a familiar path in sustainable building culture, that of research, techniques, technologies and building expertise initially developed in central Europe, that after a considerable time-lag, have begun to migrate to Britain. Slowly at first, and in the last two years at an accelerating pace, Passivhaus is becoming increasingly perceived as a credible approach to near zero energy building. What is striking is how recent the take-off has been, and in terms of certified Passivhaus buildings how still, comparatively few there are. By 2008 Germany passed its 10 000 Passivhaus building mark (though the number certified is likely considerably lower.) That year in the UK there were absolutely zero certified Passivhaus buildings. Soon afterwards the Passivhaus Trust’s website included a U-Tube video report on the International Passivhaus Association’s 2011 conference with the Slovakian passivhaus building designer Bjørn Kierulf talking through the numbers in his country, about fifteen to twenty in all, which is roughly equal to the current UK numbers! So although there is currently plenty of excitement Britain is in a different category when compared to Germany, the main comparable sized country, while also lagging behind other smaller countries where Passivhaus found acceptance much earlier, such as Sweden, Denmark, and Austria.

In as much as this represents a breakthrough for Passivhaus in Britain, how has it come about? Though Passivhaus is presently making its way into the mainstream, the origins of those who originally took up its cause, throw illuminating light on the growth, development and partial metamorphosis in a particular, specific strand of sustainable architecture building culture in Britain. It is also something of a textbook case of how the success of specific approaches to sustainable building has triggered radical change in sustainable building. While the sustainable building community has hardly been homogenous in Britain, specific values, characteristics and approaches gave the community a definite identity, which has in recent years been seen to change, - some would say evolve - and splinter, indeed realign into something different. For some this is the inevitable ‘growing up’, for others it’s a matter of moving on with changed times, for still others its a consequence of what happens in groups, when after years at the edges, influence, and what comes with acceptance, is tasted. These are the lens through which to view the current Passivhaus emergence in the UK, and also the Association of Environment Conscious Building network, (AECB) the organisation which has been at the heart of a particular kind of sustainable building culture, and who have been instrumental in the Passivhaus emergence in England and Wales. This isn’t to say it’s the only source but what is so marked is how many among the AECB’s nationwide network, bought into Passivhaus both individually and collectively, providing something of a shared outlook and culture, for the continental building approach to find its UK feet. In this, they seem to have been drawn to the thoroughness of the Passivhaus approach, a trait common to European colleagues, as well as finding the challenge of energy efficiency a particularly appealing technical, intellectual, and personal puzzle in need of resolution.

Founded in 1989 by builder and homesteaders, Keith and Sally Hall, the AECB – which these days describes itself as the Sustainable Building Association - grew in the following few years to encompass a network of committed, passionate architects, engineers, a small number of builders, and particularly, apparently, energy experts as well as others working away at the edges of the construction world. Although in its first ten years the AECB saw itself as attempting to engage with the mainstream, its membership was radically so at odds with Britain’s building culture’s status quo, that for the most part, it damned the mainstream whole. As for the UK construction industry, particularly those parts which interfaced with AECB members, for instance its research satellites responsible for developing sustainability in the sector, the AECB – if they had heard of it - was mainly considered as wholly a ‘grassroots’ organisation and was either ignored or dismissed, or both. Often the dismissal was of a blanket “nuts in the wood” form. What was serially missed was that here was an extensive and committed network with a membership who were and had developed practical and straight-forward working solutions to energy issues in buildings.

Pennylands, Milton Keynes
Wikimedia Commons
One of the experimental houses from Milton Keynes' 1986 Energy
World Housing Expo. Photo - Wikimedia Commons
If early AECB members were a mixed bunch, there was one grouping who arrived with considerable if specific low energy building performance experience. This was the community which had co-elesced around the decade long low energy research between the mid 1970’s to mid-80’s in new town Milton Keynes. The research originated with the Milton Keynes Development Corporation making Britain’s most ambitious new towns experiment into a leading low energy hub throughout the eighties. Led by two departments at the Milton Keynes based Open University, the Energy Research Group and the Alternative Technology Group, these research clusters attracted quite a few youthful would-be radical energy researchers. One of those was a young Peter Warm, who would go on to be the AECB’s first chair while pursuing a career in energy consultancy, which today includes managing one of the main Passivhaus training courses. “The Milton Keynes Development Corporation was very influential because it had real powers, which included funding a generation of low energy research and building projects, after the 1973 oil crisis” says Warm today. He arrived fresh faced at the door of the Energy Research Group and began working as part of a team monitoring the latter stages of the Development Corporation’s first 1979/80 low energy building project, Pennylands. At Pennylands, 177 houses had been constructed, half to then UK standards, the second half to benchmark Danish and Swedish standards. “We learned so much,” says Warm, who’s first unpaid work was screwing in window sensors at Pennylands. He would stay on at the Energy Research Group for several years, consumed by the challenge. “It was a fascinating problem. We could see the solution, but it was how to really solve it.”

The Development Corporation would continue with a second phase, the Linford low energy houses were built to the Pennyland Area 2 standards and in the high profile 1986 Energy World Housing Expo the UK’s first sustainable housing demonstration project, showcasing 51 cutting edge low energy housing examples for the time. The results from the Energy World research would feed into national housing efficiency standards, including the Standard Assessment Procedure or SAP, which continues to be used today. When as the research began winding down in the late eighties, Warm set out on his own as a low energy consultant. The problem was already clear to him, it was about how to improve buildings insulation and airtightness, recalling how although it was to be a few years before he would encounter Passivhaus, “there’s nothing new under the sun.”
The Saskatchwan Conservation House 1976,
Photo University of Regina, Canada

Warm, like others on the early AECB steering committee, was first introduced to the new fangled middle European approach by another AECB member and independent energy consultant, David Olivier. Described as one of the “best theoretical energy researchers in the UK”, by Chris Herring, the current AECB chair and founder of the Green Building Store, the green construction consultancy, Herring also notes that Olivier prefers to work independently, rather than within institutions. By the turn of the century Olivier had been involved in energy issues since the seventies, working early on within the Energy Resources Research group.  Olivier attended many of the period’s conferences, visiting some of the earliest wave of low energy experimental buildings which appeared dotted across the developed world in the ten to fifteen years after the 1973 oil shock. One of the earliest of these was the Saskatchwan Conservation House, which Olivier had read about in 1976. He would continue through the next years to visit other early highly insulated, low energy experimental buildings, in Sweden, Denmark Canada, Germany and Austria including some which influenced the Milton Keynes experimental housing, such as those showcased at the 1977 Danish Skive environmental housing fair. Not surprisingly Olivier became familiar with the early Passivhaus research. This had begun in the late 1980’s, leading to the first buildings to be completed in Darmstadt in 1990, precipitating the founding of the Passivhaus Institute. In the same year Olivier met Passivhaus’s co-founder, the one time particle, turned building, physicist, doctor Wolfgang Feist. During these two decades Olivier produced ongoing research, detailed and critical of the established building industry standards. This included Government research centres such as the Building Research Establishment (BRE) – for which Olivier also conducted energy consultancy - which seems to have ignored Olivier’s research. This, despite the respect which Olivier’s work was held in, by various colleagues. “David was probably doing the best research outside Austria and Germany,” says Liz Reason today, a management and change consultant who became central to the AECB Passivhaus story, and whose charmingly named home, Lower Watts, in Charlbury, Oxfordshire, Olivier had helped design.

Kranichstein, the first Passivhaus built in 1990 as part of the
Passivhaus Institute's research in Darmstadt, Germnay
Photos: Passivhaus Institute
If the nineties was the decade when Passivhaus began to gain traction in Germany, Switzerland and Austria, very little of this made any impact in Britain. Olivier, who by the mid-nineties had set up his own consultancy, Energy Advisory Services, continued to publish research, essays and articles including in Hall’s Building for a Future, the AECB’s sustainable building and architecture magazine, as well as, according to Liz Reason, a million-word book, through the Earth Resources Research. In 2000 Olivier reported for AECB magazine,on that years – the fourth – international Passivhaus conference, and joined the AECB’s organising committee.

The inevitability of the AECB's journey towards becoming the primary vehicle supporting Passivhaus in Britain is an intriguing question in itself. With its origins in the post 1973 oil shock overwhelmingly self-grown sustainable building culture, the AECB seemed through the nineties to be perceived as both irrelevant and an irritant to the mainstream UK building culture. Like other groups which had originated from the seeding ground of the seventies ecological alternative culture such as the Permaculturalists or the Schumacher Society, the AECB wasn't ever short on criticism of the mainstream, sharing
The water powered cliff railway and arrival shed.
Examples of early building and alternative technology at
CAT in West Wales. Photo CAT
with these others the kind of solidarity of identity that comes with opposition to dominant orthodoxies. Indeed, the early membership comprised many from the building wing of the '70's alternative counter-culture, co-elescing around shared eco-passions; natural materials, small scale renewable energy, and other alternative technologies, resulting in buildings which conveyed a mix of community, health, rural futures and spirituality; a vision of future ecological lifestyles closer to and in balance with the natural world. What it's president Chris Baines called ''a craft led building culture', in practice referred to timber-frame straw-bale, greenwood, earthen buildings, plus exotica like earthships which all vied for attention in the pages of Building for the Future while various early iterations of eco-technologies; heat pumps, solar water heaters, other forms of micro-energy, natural insulation and natural paints were discussed by their advocates alongside arguments about the merits of timber sourcing accreditation or the general hopelessness of Government legislation. Debates wove around single-issue subjects led by the most passionate, which to outsiders, and the mainstream construction sector might have appeared like arcane sustainability marginalia. If the image was of the building wing of the meusli eating, sandal wearing types lampooned in the mass media, the fact that technical problems were shared and solutions found amongst members, a group mind uninterested in looking after number one, added to this image. There were sister bodies such as Centre for Alternative Technology (CAT), between which traffic and projects flowed and information was similarly shared, while a small group of AECB 'house' architects, such as Architype, EcoArc, SimmondsMills and CAT's David Lea and Pat Borer, and their buildings, would invariably appear in the magazine. If the architectural sensibility shared a tradition, it was
Walter Segal self building principles in action – Self-build home in Brighton.
Photo Walter Segal Trust
as heirs to the sustainable simplicity of Walter Segal. Other, generally more metropolitan, practices that didn't seem to fit this profile, from Richard Rogers to Sarah Wigglesworth or avant eco-visionaries like Paolo Soleri, never seemed to feature. Although the urban was discussed, the image of the eco-future summoned up tended to a rural, agriculturally hued one. Bill Dunster was one architect, who was part of the mix, adding urban eco-districts and his iconoclastic voice to the mix. Displaying both the best and the worst of a like-minded community, united in part by its critique of the mainstream, the research carried out during this period was a rich compost of rigorous building work, unified by the desire to answer the question, does it really work? Rigour was perhaps the AECB's strongest suit. Its weakness was that it was an organisation that talked amongst itself, huffed and raged, but essentially ineffectual beyond the borders of believers.

Some of this is recognisable as a strain of building romanticism that has hardly dispersed in the intervening decade. Amongst this, two related impulses began making themselves heard in the immediate post millennium years. One was the grouping of energy specialists, who formed a significant constituency within AECB, including David Olivier, who’s thinking was genuinely respected among the membership. “We’d all moan at him, but David was able to see what’s coming,” recalls Warm. There were others, including Professor Robert Lowe, a building physicist working out of the Bartlett school of Architecture, London and Leeds University; John Willoughby, another early energy consultant; Mark Gorgolewski, who worked on a PhD on energy efficient housing from Oxford Brookes, leading into an academic career in Canada, and others, who all continued developing and contributing to knowledge of low energy building design. Some worked as consultants for BRE, while critical of the building research centres timidity. They were called, according to another AECB member and one-time BRE man, Neil Cutland, ‘the energy mafia.’

The second strand drew from an acceptance among some within the broader AECB membership that romanticism could only get you so far. You could indeed build a beautiful, very low embodied energy, rustic greenwood timber-frame home. This was all very well, but these newborn sceptics would ask inconvenient energy questions of the building, once finished and occupied. They would point to the folksy log burning stove in the middle of the front room, looking good but bumping up the energy and carbon footprint, unless much more rigorous notice was taken of issues like insulation and airtightness. As it was energy and the reality of climate change was shifting some members perspectives towards different ways of thinking. Indeed, energy was becoming the new watchword.

CAT's A-Teich rammed earth information
centre before opening. Photo CAT
It would articulate itself in different ways. One significant change was when Andy Simmonds became chair of the AECB in 2003. Simmonds is one half of the architects SimmondsMills, with architectural partner Adele Simmonds who’d started out as students involved roundwood projects at Hooke Park furniture school in Dorset. Fresh from working on CAT’s new Autonomous Environmental Information Centre, the A-tEIC building, where he’d been responsible for its experimental rammed earth wall, Simmonds, wearing his new AECB hat, found himself increasingly pondering whether the AECB’s energy approach was in need of an overhaul. Herring: “Andy believed the AECB was not doing energy very well and that work and training on energy standards needed introducing.” “It was great when Andy became chair,” adds Warm, “because suddenly we had an architect into energy, instead of all the energy engineers.” John Williamson who worked with Simmonds on the A-tEIC building, and would go on to complete the first certified Passivhaus buildings in the UK, had arrived at a similar conclusion. “A lot of people were doing assignments which challenged the conventions; straw-bale, oak windows, with wood burning stoves – but they were so un-airtight, it was daft. I began looking at the current uses, and so started to connect it with energy.” A definite energy group was beginning to appear within the AECB’s ranks, the beginnings of a fissure was taking shape between the old school romantics and those who, in Williamson’s words, “wanted to chase this.”

A second strand to the energy issue was initiated by Olivier, when over the same 2001 summer, Building for A Future published a long piece of Olivier’s, outlining and comparing different national energy standards and proposing that the AECB could and should develop its own new building standards. The overview outlined different standards regimes such as the Swiss Minergie and the Canadian R-2000 standards, and also included the Passivhaus standard. All of these regimes were compared in relation to the 2002 Building Regs, which Olivier termed Factor One. The AECB standard, he suggested, could be called Factor Four, and would thus promote an average four-fold reduction in the levels of housing energy use. Factor Four also happened to be title of the then current Amory Lovins and Ernst Von Weizsacker energy-reduction bestseller. The response from members was mainly positive, striking a chord at a perception of a lax and complacent UK standards regime and the rethink entered into a second stage. “The question was,” recalls Herring, “how do you find a methodology which works? Through all this time we weren’t really aware of the Passive Institute.”

At the beginning of 2003 these moves were given a further jolt, when Howard Liddell, Edinburgh Gaia Architectural Network and Nick Grant, who had long been involved in natural drainage systems running Elemental Solutions, co-authored a provocative manifesto-like piece titled ‘Eco-Minimalism’ in which much of the basis of a whole wing of sustainable building and architecture, which included using various eco-technologies as a core strategy reduce a buildings energy and carbon footprint, was unceremoniously taken to the cleaners. Their prime piece of evidence was photo-voltaics, which the two authors contended were often used on buildings to sex up their eco-credentials and make the client feel good while doing much less to actually draw buildings energy usage down to levels which actually had a palpable influence. A much smarter approach, Liddell and Grant contended, was to focus on the building doing the work, so the design reduced the need for technological add-ons. This would evolve into a core ingredient of what is now known as the ‘Fabric First’ approach to building. Liddell would go on to publish an updated version of the essay in book form, calling this reliance on the technological fix, ‘Eco-Bling.’ It was a phrase which stuck. In and around the AECB you didn’t have to listen that hard to hear the dull thud of controlled detonations taking place.

PHPP calculation comparison graph between Passivhaus and low Energy House
examples - Passivhaus Institute
For the AECB the momentum to whole-heartedly embrace energy was shaping up as a sea-change. “I supported the energy question a lot,” recalls Herring, “though some in the association were thinking, ‘God, it’s all about energy.’” The concerns were timely as well. Both at a public and a political level the wider culture was beginning to wake up to Climate Change, to environmental challenges, and different Government bodies began emerging with significant amounts of money available for sustainability related grants. Carbon, as much as energy, was beginning to be talked of as needing to be accounted for in a buildings footprint. A wider recognition that buildings performance would require significantly more rigorous attention was beginning to be acknowledged. The instrument for such tightening was the building standards. The jeremiads at the AECB, seemed, after all, to have a point.   The environmental performance dimension of British building standards had since 1995 been devised around part L of the Standard Assessment Procedures (SAP), the Government energy standards overseen by BRE, although for the AECB, it was SAP which were partially at the heart of what was so lax in the standards world. One particular thorny issue was that that the Government’s energy rating approach, with SAP as its basis, often rewarded using ‘eco-bling’, as a counter-measure to the actual energy and used in buildings themselves. Simmonds, with his new role as the AECB’s chair, began working with Liz Reason on how the AECB could develop its own standards. Still it would be a further two years, 2005 before Feist, Darmstadt and the Passivhaus Institute really appeared on the horizon. “Andy and Liz were asking where do we go from here, and the response began to percolate that the AECB could base their standards on the Passivhaus Institute’s computer programme, PHPP. The thought was, ‘if we were to commit to this route, where would this leave things’? Would it leave us far out on the left field? It felt terribly important.”

The AECB group could see a funding opening for research and dissemination of an approach for measuring buildings energy use, based on the Passivhaus Planning Package PHPP rather than BRE’s official SAP software. A first meeting with Feist and the Passivhaus Institute resulted in the go-ahead to base the work on PHPP, although the key difference, was that the approach concentrated on three steps; Bronze, Silver and Gold, rather than focusing on standards. The bid went in under the name CarbonLite had dreamt up; CarbonLite, as a new energy standards programme, and was successful. Flush with considerable funding for the first time - £140 000 - the arrival of a serious tranche of economic support would also trigger a process which would in time draw the AECB closer into the heart of the construction sector, influence and transform relations with any number of organisations it had once stuck out like a sore thumb from. The work immediately in hand was to harmonise aspects of the different energy standards of the PHPP and SAP energy programmes; a challenge, given that the former used more conservative external and the latter more optimistic internal dimensions for heat loss area. As 2006 drew to a close, the AECB was moving towards becoming a much more energy-centric, indeed ‘Fabric-First’ advocacy organisation. The wider, seventies rooted alternative vision, rural in essential emphasis, natural materials-centric, and part of a larger alternative futures sensibility, was falling by the wayside.

CAT's rammed earth information centre
once open. Photo CAT
Thanks in no small measure to David Olivier Passivhaus had been on the AECB’s radar for several years, turning the organisation into a hub of early UK activity. In this respect they were not entirely alone, however. Looking back Simmonds identifies three groupings. “As well as the AECB there was the BRE’s Passivhaus Unit, and a small number of pioneer architects, including John Williamson, the west Wales architect, and the London based Justin Bere. Although BRE and the AECB already had a long history, with a number of the AECB’s energy, as well as water and other, consultant specialists working as consultants for BRE, both their approaches and cultures were so different, that for some they were akin to a clash of cultures. As to architects, only John Williamson, seems to have been actively pursuing Passivhaus prior to 2006. A year later, things had changed dramatically with these different, if at times, intertwined Passivhaus hubs, converging to propel Passivhaus into the British building cultures’ consciousness.

Harmonising the two SAP and PHPP approaches, however, was not just a matter of number-crunching. With the previous decade one of the AECB intermittently at loggerheads with BRE, the more radical, even militant, energy activists seeing complacency in the official energy line as defined and overseen by BRE, the BRE engineering types apparently dismissive and defensive about these challenges from a network of outsiders. The tensions had been ongoing for years, descending for periods into situations where neither party was talking to the other. “The thing with BRE is a whole other story,” says Warm today. Still, there was also recognition that the two organisations could bring skills and experience to the table, which wasn’t possible apart. They had already collaborated on a web-based project in 2001. Things also took a new turn, when, in the early 2000’s when BRE began waking up to the significance of the continental Passivhaus approach. When Neil Cutland arrived in 2002 to take over running BRE’s Housing Energy Efficiency Centre, he was already familiar with Passivhaus. With a career path reflecting others in the energy field, Cutland had begun his working life at the Milton Keynes Development Group in the eighties involved in monitoring the Energy Park’s performance. Despite charitable status, BRE had become a commercially run and driven organisation, after being privatised in 1997, as one of the last acts of the Major led Conservative administration. This would be reflected in Cutland’s next steps regarding Passivhaus. He soon organised a study tour to attend the 2002 International Passivhaus conference, held that year in Hannover.  A group of 30 Brits travelled over, including Olivier and John Willoughby, as well as three BRE staff. The conference included a number of building visits, and Cutland returned feeling “quite excited,” immediately setting to planning a Passivhaus ‘business stream.’ In 2004 this was launched as BRE’s Passivhaus Unit, with the Unit initially offering consultancy. Led by one of Cutland’s team, Gareth Hodgson, the Passivhaus Unit began
Frankfurt Riedberg School, one of the city's many Passivhaus
schools that has been completed as a result of the city's Passiv
school regulation. Photo International Passivhaus Association
work on developing a range of projects, essentially for different segments of the building industry. The Passivhaus Unit, supported by BRE’s deep pockets, opened the way for BRE’s influence on what seemed likely to be the emerging UK Passivhaus constituency and market, establishing itself early on as a source for information and expertise on Passiv principles to the wider building sector. Under Hodgson the Passivhaus Unit grew over the middle naughties years into the influential Passivhaus UK body, a conduit for disseminating information and running CEPH certification – and other - courses across the construction sector.

It was CarbonLite, which rekindled the conversation between BRE and AECB that had been spluttering along semi-dysfunctionally. With the Passivhaus Unit up and running, a rapprochement between the very different cultures of AECB and BRE continued, and the two parties began to work together, along with a relatively new Government funded body, the Energy Saving Trust (EST) launched in 1993. For a while the divide felt somewhat surreal, as both parties grappled with finding a common shared language. Carbonlite was forcing the issue, and was instrumental for “the AECB to find a way to grow up” says Simmonds now. Cutland, who is also an AECB member, agrees; “the arguments are in the past,” while observing that regarding SAP and PHPP, the two standard regimes “are trying to do different things.” Within the AECB there isn’t either a path or desire to go back to the old times. Still, Simmonds states that BRE now acknowledge that they ‘missed a trick’ with Passivhaus, and also recognised that that BRE, in connecting into AECB, were tapping into “a wealth of experience. We’ve all got other jobs, and we’re experts. We’ve all built things, designed things, and sold things. It’s feet in the potato trench, head in the stars, and we know what we’re taking about.” This may have been the case regarding energy but as Liz Reason laughingly – in a friendly way – observes, it didn’t extend to the organisation’s approach to promotion. “Hopeless, dreadful! What kind of branding does the Association of Environment Conscious Builders convey?! They liked to talk amongst themselves, but couldn’t understand they needed to engage.” Reason, aware of presentation, brands and the power of language, developed the Carbonlite identity. When it was launched in 2006, the easy on the ear two-phrase name rang bells in building sector ears, and quickly became popular. It also signalled a further departure from the old ways of doing things and the beginnings of a new chapter in the AECB.

Continental comparisons: Frankfurt Housing before and after Passiv
refurbishment including thermograph air leakage imagining.
Photo International Passivhaus Association
Although there was movement of a sort out among the potato fields, as the second half of the naughties dawned, no Passivhaus projects were on the horizon in any part of Britain. Still by 2006 the growth of awareness in the need to move towards a more rigorous sustainable building culture among a wider constellation of architects, engineers and other building professionals was expanding significantly. This reflected changes in the wider culture. While AECB members were busy discussing, air-tightness, u values and insulation, the early 2000’s had seen environmental issues taking on a new seriousness among much larger segments of the UK public, both in the professional world and at a cultural level in society; climate change, and carbon issues were taking off. One consequence was that mainstream architectural and building culture began, if at times seemingly grudgingly, to acknowledge that building performance would require attention. The more foresighted in the industry could see that new regulation - with the New Labour Government administration both noting and responding to increasingly alarming Climate Change research, and heightened public concern, – was on its way not too far down the road. Sustainability was gaining the kind of gravitas that had eluded it for decades, and with the building energy contributing between 40% and 50% of energy and carbon emissions, (depending on who you asked) convincing strategies for drawing down energy use in construction was moving up the British political and architectural agenda. The AECB’s embrace of energy can be also be interpreted in this light, a collective realisation that energy performance was going to have to be addressed if the likely Government initiatives were to have any effect. Housing, the largest proportion of British buildings, particularly was increasingly becoming a focus, and by the end of the same year, 2006, the British Government launched the Code for Sustainable Homes, a central plank in its strategy that all new residential buildings would be legally required to attain what were called Zero Carbon and Energy levels within the next ten years leading to 2016. For the optimistically minded, in an astonishingly short period, the CSH had arrived, signalling that steep, not to say vertical, cuts in building’s energy and carbon emissions. Divided into six levels or codes, CSH, outlined the requirements which needed to be met for these levels. At first voluntary, CSH would become both mandatory, and tighten in levels, during the envisaged ten year path to zero carbon of new housing by 2016. It seemed like good news. Energy issues were being trumpeted right at the heart of Government. For others, however, the CSH, didn’t seem quite like such good news, when the small-print was examined. Although formally the AECB welcomed the ‘whole house’ approach, others were more critical. Jon Broome, one of the founders of Architype wrote of both of missed opportunities to raise housing construction standards, and of ignoring many significant aspects to sustainable building. And Nick Grant, in a 2007 update to the Eco-Minimalism text, pointed to how CSH appeared to encourage the application of eco-technologies on buildings, while ignoring fabric first as an approach, particularly when it came to meeting the higher code 5 and 6 levels. Passivhaus projects were penalised, typically only reaching code 3. CSH, wrote Grant, was ‘the antithesis of Eco-Minimalism.’ With CSH launched, there was suddenly, that much more at stake for AECB’s alternative Carbonlite standards.

CarbonLite was launched amidst this heightened period of Governmental departments commitment to action. The three gold, silver and bronze steps proved an accessible headline process for those looking for energy standards guidance. Difficulties and differences with BRE were water under the bridge and the Carbonlite guidance, based on the Passivhaus Institute’s PHPP programme, began to be picked up by those working on or interested in sustainable projects all over the country. Supporting the energy standards aspect were accessible descriptions of the core principles and methodologies for calculating heat loss and emissions. As a second strand of Carbonlite the AECB began training programmes which proved popular over the next twelve months, as did a discussion forum and advice outlined on the site. Information was being downloaded continually and the AECB’s stock continued to rise, with doors opening into various Governmental departments charged with developing policy for decarbonising the country’s building stock. Yet by the end of 2007 not one certified Passivhaus had been built in Britain.

Y Foel by John Williamson Construction – Britain's first
certified residential Passivhaus
Y Foel - interior
Photo's John Williamson Construction
John Williamson, after serially migrating back into the West Wales eco-scene around CAT over the previous fifteen years, settled permanently in Machynlleth in 2002, and set up a practice over the 2002/2003 winter. The next summer Williamson came across the PHPP software on the web, but since it was in German, “I couldn’t understand it.” Fortunately the next year the PHPP software was translated into English, so Williamson ordered a copy, and was startled to realise that all the spreadsheets were relevant to and could work with his designs. “I identified with the engineering, which had an honesty to it.” That summer, 2004, he made contact with the Passivhaus Institute in Darmstadt. “They were very keen, that someone from the UK was in touch, and were very accessible, and open.” Over the next two years Williamson built on this first introduction, tracking down components and finding the bones of a supply chain that could help him offer Passivhaus designs to his West Wales clients. He uncovered several potential companies in Germany and Austria, including Vorarlberg’s pioneering heat pump company, Drexel & Weiss. In 2006 he attended the International Passivhaus conference with David Olivier. He remembers asking each stallholder, ‘have you got the certification?’ A few months later Williamson’s company, John Williamson Construction started on their first Passivhaus project, a residential home, Y Foel, using the accrued knowledge that they’d picked up over the last two years. Y Foel would go on to become the first residential Passivhaus building to be certified. During the latter half of 2006 Williamson also began discussions with Powys County Council on a multi-use community building in Machynlleth, Canolfan Hyddgen. As the discussions with Powys Council continued, awareness that gas prices were about to increase by 40% during the 2007 winter became a talking point. Powys was committed to a 30% CO2 reduction by 2012 and 50% by 2017. If a Passivhaus design approach to the centre’s design was applied the figures estimates that this would reduce space heating by 85%, a carbon saving of 39 000 tonnes and financial saving of £7.8 million in energy bills. Powys went for it.

John Williamson's Canolfan Hyddgen, a multi-use community building in Machynlleth,
West Wales, on site in 2007 and certified in 2009, the first non-residential building
in the UK (… and Wales.!) Photo's John Williamson Construction
The Canolfan Hyddgen centre began on site in April 2007 and was completed in 2009. It passed its certification a year later, and also scored 84.4% on the BREEAM rating, the highest in Wales at the time of testing. With his roots at CAT, where he also presently teaches, Williamson’s adoption of Passivhaus, although arguably not directly falling under the AECB umbrella, does illustrate the traffic and close connections between CAT and the AECB. Indeed, as Williamson acknowledges that the many years of CAT’s presence in Mid-Wales has been influential, including spawning a regional ecobuild culture, with a small number of architects, builders, sub-contractors and products company’s such as John Cantnor Heat Pumps, and insulation specialists Pen Y Coed, all working across the region. Much of this culture was also linked to the AECB, in one way or another. In the two years since the two Passivhaus projects, Williamson’s company have continued their ground-breaking Passivhaus work, acting as consultants for a Passivhaus campus, developed a feasibility study for Welsh School
David Lea and Pat Borer's WISE Graduate school, likely the last of
their projects. Photo CAT

buildings for Powys Council’s Low Carbon programme, Resilient Powys, and are involved in a number of new build, renovation and non-domestic – retail and gymnasium – projects, across Mid-Wales counties. Some have occasionally called this ecobuild culture, which has emerged within the three counties, Powys, Flintshire, and Carmarthenshire the Vorarlberg of West Wales, and although not really accurate, it is striking that a local, low visibility eco-culture has taken root in the years since CAT opened. Both Williamson and Simmonds are steeped in CAT, with Williamson also working on the A-tIEC building. It’s tempting to see each as the part of a new generation who have taken on the mantle presently being passed on by CAT’s two central architectural elders, Pat Borer and David Lea.

Disability Essex by Simmonds Mills
Photo Simmonds Mills
Simmonds himself, with his professional partner Adele Mills, was, unsurprisingly, by this time, applying passiv-principles to his work. A first focus was his own home in Hereford, the English-Wales border town. After beginning to refurbish the unassuming street terraced home, Grove Cottage, to Passiv-standards, SimmondsMills began work on a newbuild project, Disability Essex, a Centre for Disability Studies. Through 2008/9 Simmonds worked in tandem on both home and centre, with the latter passing Passiv certification in 2010. As with earlier projects Simmonds put the results up on the practices website, while also collating a reference document contrasting detailing and features from the two builds. This was sent out to AECB members. It was, he says, very well received, as, in his words, “a crucial reference document” free for readers to use or adapt from. Indeed other older AECB hands, including Peter Warm, extended their AECB and consultancy work in the obvious direction, by adding Passivhaus expertise as another string to their professional bow. Warm Consultancy would go on to take on responsibility for the Carbonlite Passivhaus courses. All this would feed through into the AECB community and beyond in different ways.

A third architect who had long trod low energy building path, would, during this mid-naughties period, also discover Passivhaus, Unlike Williamson and Simmonds, however, Justin Bere lived and worked in the heart of the capital. Bere, who after working for several years at Michael Hopkins, had struck out to set up his own practice to pursue his low energy passion, didn’t know, surprisingly, about Passivhaus until one day in 2006, when a German assistant pointed out how similar some detailing was to the Passivhaus approach. Bere was stunned to find literally hundreds of architects across Europe developing similar, though more advanced, skin tight buildings than the ones he’d spent literally years aspiring to. The Internet discovery led to a page announcing the annual International Passivhaus conference would be held in the Austrian town of Bregenz. Bere, unaware of the AECB, had no idea that AECB members were also heading for the biggest continental conference yet.

Passiv measures during the refurbishment of SimmondsMills Grove Cottage. I) Roof decking is prepared before
the air vapour barrier is added. II) The windows are measured and checked for airtightness. III) Airtightness measures on Grove Cottages north east corner. Photo's SimmondsMils

Up to Bregenz it’s apparent that those that had been picking up on Passivhaus weren’t metropolitan, London-centric architects. AECB has been predominantly a Welsh and Welsh borders congregated network, with an outpost in the leftover community radicalism of Leeds, Huddersfield, Hebdon Bridge. For the first time AECB’s Mid West Country network, stretching through towns like Hereford (Architype, Andy Simmonds, Nick Grant), Leominster (David Olivier and many others), Stroud (John Willoughby and Pete Warm, though Warm would relocate to Plymouth in 2009) all feature on this Celtic fringe like map. The Celtic theme continues into Wales with founder’s Keith Hall’s farm in Pembrokeshire. There was also the CAT connection in West Wales and a whole slew of building types, including John Williamson. If the Passivhaus Unit was running out of BRE’s Garston headquarters, just north of London, Gareth Hodgson was often heading for the wilds of West Wales to help on Williamson’s Canolfan Hyddgen community centre in the early years, rather than into sophisticated London.

Whether a conscious strategic decision or a more organic development the attendance of Bere, Liz Reason and Nick Grant seems to have jump-started the pace of Passivhaus’s emergence in England. One reason may have been its geographical location: Bregenz is a principal town in one the epicentres of central European Passivhaus activism, the Austrian state of Vorarlberg (See see FDR8’s A Passive Revolution Goes Active for Vorarlberg’s Passivhaus scene.) Bere encountering Reason on the edge of lake Constance, and bonding over Passivhaus, would have its consequences. Bere realised that here was an organisation – the AECB - which was as immersed in low energy issues as he was. Over the next months plans for collaborations were hatched. In Bere and his small but dedicated North London studio team, the AECB had seemingly chanced upon a group as equally committed as they were, though with all sorts of well connected links into the belly of the beast.

Visualisation of Devereux's Houghton-Le-Spring twenty eight dwelling
housing, a first for England's North East – Photo Deveureux
Though AECB’s CarbonLite shift towards energy questions was already well underway, the Bregenz conference further cemented the organisation’s overall conclusion that architects and the building community needed to accept the consequences of the Passivhaus approach. Having left a sceptic, Nick Grant returned to Britain a convert. He would be instrumental in persuading Architype into Passivhaus thinking. The level of interest was also noticeably increasing. The AECB’s chat-forum was buzzing with Passivhaus issues. Two architects took a particular interest. Both demonstrate that the AECB was drawing in practitioners from outside its traditional core community. The first, Mark Siddall, was from DEWJOC - which in 2009 would merge with Devereux Architects, to form a 250 staff practice with offices across the country and in Europe. Siddall had been asked to develop DEWJOC's sustainability strategy in 2006. Based at DEWJOC's Newcastle office, Siddall decided to take a fresh look at the brief, asking himself what the key issues were. Aware that energy, plus day-lighting and ventilation were central, he thought it important to thoroughly ground himself in the field. From there Siddall looked through much related and emerging areas, including BREEAM and passive solar and before long came across Passivhaus. Soon the AECB came up on the radar and Siddall began to be drawn into and participating in the web-debates. According to Herring, “Mark was hitting the AECB chat room every day for about six months.”

Siddall realised he was among kindred spirits. “They were examining everything from first principles, and I saw Passivhaus was being mentioned a lot. I thought, ‘this is ticking a lot of boxes.’” At first Siddall wasn’t certain, and he began spending evenings teaching himself building physics, reading research papers and getting more and more involved in the AECB’s on-line discussion. He became increasingly convinced that Passivhaus’s principles were relevant to the British context. “I saw this wonderful possibility of what it could be.” He also built bridges with Leeds Metropolitan’s Centre for Building research . the erstwhile home of building physicist, Bob Lowe “No-one else seemed to be publishing things in the same way,” he remarks now, looking back on the comparative isolation of logging on to the AECB discussion forum, the only person in the Newcastle area involved. “In the north east I was effectively alone. It couldn’t have happened without the internet.”

The first time Siddall presented his research to his DEWJOC colleagues was in 2007. It was met with an initially sceptical reception. After several further presentations, some showed more interest, although his colleague’s responses sounds like it was a disappointment for Siddall. Still with the development work done, Siddall took on a major Passiv project, the country’s first larger scale passiv-housing, 28 dwellings in Houghton-le-Spring, Sunderland, which is, currently after many delays, almost complete. Siddall also on the first UK Passivhaus Designer course at Strathclyde teaching himself expertise in airtightness and cold-bridging, and now helping deliver courses on the AECB Carbonlite training programme. Today he is recognised as one of the country’s Passivhaus experts.

Model of PrewettBizley's first Passivhaus housing, on site 2012. Photo PrewettBizley
A second architect who also became increasingly curious about Passivhaus is PrewettBizley’s Rob Prewett. In contrast to Siddall, Prewett’s practice is in London, and his Passivhaus encounter was fortuitous, down more to chance than design. In 2006 Bizley was doing extra freelance work for the UK Building Design magazine, drawing up axiometric renderings of buildings to illustrate articles, and was asked to lay out Bere Architects Focus House, just at the point that Justin Bere discovered Passivhaus. At the time, Prewett’s initial thought was that “it was a bit absurd,” with all the super insulation, and found it particularly difficult getting his head round the mechanical ventilation and heat recovery tech. “It just seemed like a big machine with all these pipes coming out of it.” ‘Was it actually necessary, was the larger question looming in his head. Yet he could see the rationale, there was rather more joined up thinking than he’d found before. With further time and reflection Prewett began to see the building sense, thinking,  “wow, that actually makes sense.” It took a couple more years, however, for him to take the approach more seriously, even though he acknowledges a predisposition against mechanical heat recovery systems, as they “seemed unnatural.” By 2007 he’d become well versed in SAP, while also researching into Passivhaus, with the principles making it increasingly evident that PHPP was a necessary tool to getting the results for aspects such as thermal bridging, that weren’t covered by SAP. “So we eventually got the package.”

In late 2008 Prewett and his architectural partner Graham Bizley were commissioned for their first retrofit for a client in Hackney North London, who wanted to do a low energy rebuild on his home. The client told Prewett about the AECB, and he went home and looked up the organisation on the web. He began checking the discussion chat-room and looking through the conversation he realised there was a readymade community discussing just the issues he was thinking about. Like Siddall, he too began participating in these online conversations, and the AECB members responded to “all the questions that had been building up in my mind. They seemed to understand, reading their stuff, and also the Carbonlite programme.” Nick Grant sent helpful emails, and Pete Warm also passed on some useful hints.

Prewett, a graduate of Bath University, who had spent most of his post training years at FeildenCleggBradley, found he was increasingly caught up with Passivhaus, and not only in building. He would become one of the founders of the UK Passive House Trust. With a focus on housing, Prewett looks back on the period as one of exponential growth of interest in passive house. “Since the first retrofit the knowledge has exploded, so that passivhaus maintenance understanding is becoming accessible at a Joe Blogs level” with the current groundswell of interest different in order, “compared to even two years ago.”

Both Prewett and Siddall, as much as Bere, were evidence of a generation drawn to Passivhaus and the approach it implied, from outside the traditional AECB community. Having qualified from architectural schools in the early nineties, all three are part of a new forty something generation of architects, currently increasingly influential within sustainable architecture. Unlike some in the AECB, they represent a different mindset, not so engaged or involved with issues of alternative ‘back to the land’ culture. Working in explicitly urban contexts, skilled with computers, aware of the significance of image presentation, mixed with some can-do pragmatism when promoting Passivhaus, are marked characteristics of the generation - reflected across the wider sustainable building world of recent years - and also another notch severing the older ties to the ruralist, ecotopian vision that the AECB had represented.

UK Green Building Council homepage
Apart from helping in converting both Siddall and Prewett, Carbonlite’s take up during its two-year life, with the sector increasingly conscious of regulatory change, was proving popular. Designed around three increasingly stringent energy step changes in the countdown towards 2016, the SCH zero carbon regulation - despite criticisms - was upping the ante in residential building, Already, the first, 2010 step-change, was fast approaching, and despite much grumbling the construction sector was being forced into adapting. Alongside Carbonlite, BRE’s Passivhaus Unit was also becoming influential. Well established, with a website gaining thousands of hits, plus courses, seminars, partnerships BRE was increasingly a ubiquitous presence at industry events aimed at the sustainability wing, such as EcoBuild Activity across the sector was increasing. One sign of this was the creation of the UK Green Building Council, to help support the SCH’s ten-year programme, in 2007. As early significant step, that of agreeing on a common definition for zero carbon, was launched in 2008 by the UK Green Building Council, through its Zero Carbon Task Force along with mapping the path towards its realisation. The task forces final report arrived in spring 2009. The previous summer, the Zero Carbon Hub had been launched to work on supporting the construction sector towards the 2016 zero carbon deadline, reporting to another newly set up body, the 2016 taskforce. This and much other industry activity was proof of sorts that sustainability had arrived in the mainstream, even if some wondered whether, come 2016, the reality would match the rhetoric.

Bere Architects Camden House, during the build
As the take-off continued, some in the AECB couldn’t help noticing that the open approach to spreading practical building knowledge learnt over the earlier years and fostered across the network wasn’t necessarily reciprocated among various of the new organisations that were picking up on Passivhaus. “I’ve always tried to share rather than encourage AECB members to keep things to themselves,” says Simmonds, frustration rising in his voice. “To give, rather than to take. I’ve always shared everything – including when things go wrong, things that don’t work.” The success of CarbonLite and the incremental growing interest in Passivhaus was bringing AECB, an organisation run on shared passions, rather than colder incentives, into full frontal contact with the ways of the commercial construction mainstream. It was a sharp contrast to the first ten years of its life, when the network had operated at the fringes, despite this having been the time much of the remnants of the 70’s alternative culture seemed to be fast disappearing, Along with various newly set up Government bodies, the AECB, having been catapulted into this more professional, though also more cutthroat, landscape, was becoming an accepted feature in the emerging sustainable building support infrastructure. For some, like Simmonds, it was hard, though his words suggest he had known that when this moment came, such an outcome was always likely. “It’s part of the natural order of things.”

Through this somewhat heady period, the AECB began to look to life beyond the Carbonlite programme, an unquestioned success, which by 2009 was running down its grant-based phase. The question which kept on arising, according to Herring, was, “where do we go from here?” Rather than any reverse, another move towards the centre appears to have felt inevitable. A sense of a bandwagon rolling was palpable. Throwing possible next steps around the AECB decided that what was needed was an actual Passivhaus establishment, to promote and provide Passivhaus information and expertise housed
Bere Architects Camden House - completed. Photo's Bere Architects
in one body. Herring, Reason, Simmonds and others decided on launching UK Passivhaus Trust, a UK version of Germany’s Darmstadt Passivhaus Institute and affiliate of the International Passivhaus Association. With discussions over the 2009 summer, the Trust was up and running in autumn 2010, just a year later, being launched the evening after the first UK Passivhaus conference in Islington ended. Owned by the AECB, the roll-call of founder members reflected the widening sector of constituencies involved, ranging from the old hands like CAT’s new Welsh Institute of Sustainable Education (WISE) graduate school, and the Scottish Passive House Centre, (which had run the first Passivhaus certificate courses,) to Neil May from the Good Homes Alliance (and Natural Building Technologies, well as representation from various certification groups. Organised to be at arms length from the AECB, with a separate board and staff was headed up by director, Jon Bootland. Some of the twenty one founder members – each contributing to the Trusts start-up funding - provide a further flavour of Passivhaus’s rapid mainstreaming; corporate members include the Austrian Trade Commission, building contractors Willmott Dixons, Global building products company Saint Gobain Isover, and glass manufacturer Pilkington Glass. The same year, 2009, professor Feist presented at a UK conference for the time first time stoking the groundswell. His keynote talk at the AECB’s 2009 conference generated considerable excitement, as did a return visit to London, the early 2010 Bere Architects organised Camden talk, which Prewett witnessed six months later. “I was amazed to go into the room and find it packed with architects waiting to hear Feist.”

On the ground, the physical result has been the arrival of Britain’s first wave of genuine and accredited Passivhaus projects, across a broad geographical range of the country. The first pioneering wave of buildings were beginning to arrive. The earliest accredited buildings were the John Williamson Construction Canolfan Hyddgen community centre and Y Foel house. Herring’s Green Building Store Denby Dale House, which had begun on site soon after the 2007 Bregenz conference, a simple stone two storey new build home in the Dale village near to the Green Building Store’s Huddersfield
Lime and Larch Houses at FutureWorks in Ebbw Vale. Photo Bere Architects
Architype's Wolverhampton Oak Meadow Passivhaus
School. Photo Architype
home. It was completed and certified two years later in 2009. The same summer the first of Bere’s Passivhaus projects, Camden Passivhaus was underway. Another domestic dwelling, the timberclad building in a leafy and upmarket part of Camden council, North London, is the most consciously architectural example of the first wave, seemingly significantly influenced by Bere’s Vorarlberg visits, looking not unlike well known Vorarlberg architect Hermann Kauffmann’s residential designs. It was completed during the next 2010 summer.

By 2009 and 2010 other private home’s were beginning to appear, including Underhill House by Helen Seymour Smith as well as several other partial self-builds. The same autumn, SimmondsMills completed the Centre for Disablility Studies in Essex to full passive specification. The same summer, 2009 it was clear that Passivhaus was also being taken up by a couple of architects working on new sustainable school buildings. Architype, influenced by Nick Grant, had bought into Passivhaus and were going through iterations of designs, but not getting them close to any building sites. In the West Country Devon County Council’s architectural department were already building a Passive primary school, Montgomery school in Exeter, and further education college in Barnstaple, down in the South West peninsular.

Two New Passivhaus Community builds. Green Base Community gardening centre by SimmondsMils in St Helens, Lancashire and Mayville Community Centre's Passivhaus retrofit in Newington, North London by Bere Architects, complete and with the superinsulated windows being guided into position. Photos SimmondsMills, Bere Architects, & Abraham Garcia
It was in mainstream housing, however, with the countdown to the zero carbon target for 2016 already ticking away, which was the draw for many architects. Ahead of the curve on this front, Bere Architects were designing two experimental, affordable houses as part of Future Works, a big South Wales building programme on the edge of ex-coal mining town, Ebbw Vale. Launched by BRE Wales the two 2 and 3 room domestic housing provided the starting point for part of a larger, though now mothballed and renamed The Works showcase environmental development of 700 plus homes. Titled Larch and Lime Houses respectively, the pair of houses have been designed specifically to very low affordable housing budgets, to meet contrasting levels of energy use, and with the very different South Wales climate in mind, passed Passivhaus Institute certification during 2010. In the last twelve months a number of projects have either been completed or are on site, including further one off community projects by SimmondsMills; GreenBase which mixes horticultural into community centre functions, in St Helens, Lancashire, and Bere Architects Mayville Community Centre Passiv-refurbishment in North London.

Sunnylands – a residential newbuild in the Borders by
VennerLucus, which uses a twin track hybrid approach of
photovoltaics and Passivhaus. Photo VennerLucus
VennerLucus completed a Scottish borders house in 2010, amalgamating Passiv with Dunster’s solar zero energy approach, as Susan Venner worked with Dunster for many years, including as project architect on BedZED. In London there’s 4Orm’s North London Aubert Park, which is a five apartment multi-house block. In the North East, Siddall is finishing off the Houghton Le Spring Racecourse housing. Larger more mainstream companies are also beginning to make moves. Architype are partnering the well-known Rick Mather practice on a block of flats, also in Camden. Another example of its mainstreaming is Midlands corporate practice CPMG, which have undertaken a sizable first Passive office for Interserve in Leiston near Leicester. In Kent Eurobuild’s Hadlow College’s Rural Regeneration Centre by Eurobuild was the first college to receive certification in 2010.

The period of firsts is beginning draw to a close as each different first is claimed, and further projects progress along the pipeline. Along with newbuild, the Retrofit for the Future programme is in its latter stages, with a cross section of its 90 plus projects, including practices which have committed to Passivhaus, looking at how to refit a variety of older, if primarily older housing types. This also includes both Bere and PrewettBizley Architects. Rob Prewett notes that many of these research projects were informed by Passivhaus issues and ideas, about cold-bridging, heavy insulation and walls, even if they weren’t technically, passiv-projects. A quick look at the Trust’s internet accessible map of UK buildings, suggests that it’s still early days, with just over thirty English and Welsh projects, half of which are still to be certified, with a third of the total Retrofit for the Future research.

Hadlow College's Rural Regeneration Centre by Eurobuild. Photo's Eurobuild
Thirty isn’t exactly a huge number, and highlights how Passivhaus in the UK remains, despite the upsurge in interest, but one strand in the sustainable and general architectural culture. With its emergence critical voices are also becoming louder. They divide into two core groupings; aesthetic and eco-ideological. The former seem mainly to be a variant on a larger architectural critique, with Passivhaus an example in the wider argument that sustainable architecture isn’t genuine architecture. This perspective, which continues to be heard across the architectural world, expresses a concern design issues are being sacrificed to a fundamentalist sustainability, which in this instance contains a Passivhaus accent. More vociferous is the struggle between those who see the Passivhaus as the sustainable building path ahead – at times giving the impression of it being the only path - and those who are equally strong-minded about different approaches to sustainable building. Probably most high profile is BedZED’s Bill Dunster’s arguments that Britain’s milder climate means passive solar design is sufficient, while electricity eating ventilation systems are unnecessary.

4orm's Aubert Park Terrace, North London complete . Photo's 4orm
and on site
Apart from the ego-bruising of winning and losing of arguments, are the larger issues at stake. Five years ago those involved in Passivhaus numbered, according to Passivhaus Trusts Bootland, approximately a hundred people principally, if not completely, clustered around the AECB. Today Bootland calculates there’s five hundred, and consequently considerably more at stake, from professional futures and individual livelihoods to the direction of zero carbon housing policy in Britain. Today it’s clear that the AECB is in a very different position to half dozen years ago. Carbonlite was one step to bringing AECB in from the margins and establishing the AECB as a significant player in the construction sector. With the Passivhaus Trust a next step further into the construction industry has also taken place. For instance the AECB acted as technical consultants on Technology Strategy Board’s Retrofit for the Future central R&D to the next stages of drawing down to zero the country’s existing domestic building stock carbon emissions. Neil Cutland also represented the AECB on the Zero Carbon Hub, ensuring that the Passivhaus KWh per m2 heating demand calculation is to be included in the 2013 regulation guidelines. Without the representation Peter Warm thinks it wouldn’t have been discussed, noting how, “all others on the committee drew a blank when this was raised and why it is important.”

Thermograph imaging of airtightness on Retrofit for the Future Lena Gardens project in
West London. Image UK Passivhaus Trust
With 40% of emissions coming from buildings, such decisions have big consequences. The promise for those who win construction industry arguments about the most effective way ahead to reduce energy and carbon from buildings are various and considerable, and of course, include contracts and longer term rewards. Allied to the regulatory tightening of belts, the last ten years has seen, as in so many other sectors, a newly minted green technocracy blossom at the meeting points between Industry, Government and Academic research, with this strata of new professionals ably talking the green technocratic building talk. In distinct contrast to just ten years ago, this new technocracy recognizes, albeit with different glosses, how the Green economy, despite the economic downturn, is a central part of contemporary economy’s future health. Just as sustainable building is a significant slice of the Green economy, so the emerging British Passivhaus sector is a sub-category, arguably filed under the much-lauded CleanTech sector, to be measured with potential economic value in mind.  Quite a number of jobs are riding on its future, ranging from companies developing homegrown Passiv technologies and PR outfits servicing architects and other organisations requiring on message promotion and publicity, to the whole educational scaffolding which has grown up to support CPD, introductory and accreditation. That’s certainly one way to understand the four accredited courses that are up and running, run by Warm Consulting for the AECB’s Carbonlite programme, BRE, the Passivhaus Trust, and Scottish Passive House Centre and Strathclyde university lead to a Certified Passivhaus Designer (CEPH) qualification, after passing a written exam overseen by the Darmstadt Passivhaus Institute. So far one hundred have been awarded the CEPH qualification. Shorter courses, and those who have attended without taking the exam, up the numbers considerably. The Strathclyde-SPHC course have seen around one hundred through their doors since they started up the first UK course in November 2009, while a similar figure have been through BRE’s course, run half a dozen times since beginning a year later in November 2010. Nottingham University is about to become the fifth mainland course to be up and running. At times the growth in training, and professional capacity has seemingly gone hand in hand with increasing scepticism as to their motivation and rationale, given attendance can cost over £2000 per person. For those who’ve passed the certification process, it is usually another string to their professional bows; whether the demand will be there to keep one hundred plus busy is going to become clear over the next years.

St Gobain-Isover multihouse 2011 student prize winner
Not surprisingly Passivhaus’s commercial potential has also influenced perceptions of the UK Passivhaus Trust, and that of the AECB. Its launch was seen by a few as another step in the further commercialisation of the micro sector, explicitly set up to tap into the upsurge of interest. It’s hard to argue with the suggestion, that quite a few of those Corporate founder members joined the Trust as a way to access pertinent markets to their businesses. At the recent conference the French multinational St Gobain Isover’s launched the UK element to its annual international Multi Comfort House competition, with Passivhaus Trust member Nick Grant as part of the jury. St Gobain’s link up with the AECB goes back to 2008, when the AECB were a junior partner in St Gobain’s launch of ‘the Multi-Comfort house’, which ‘build on the Passivhus concept. The partnership has continued, St Gobain Isover announcing, the summer of 2011 its sponsorship of the Carbonlite certification courses. Although such heavyweight corporate support was welcome for the AECB and the Passivhaus Trust, the presence of a tranche of mineral wool insulation companies, including Rockshell , these were further signs that Passivhaus is inevitably, in part, just another product. When the young Scottish architect, Kirsty Macguire asked a question from the floor about why there wasn’t more emphasis on natural insulation, she may not have had in her mind St Gobain, the multinational who employ over 16000 people worldwide with, in 2010, a £3 billion turnover, but it would have been pertinent. For some, including Grant, the arrival of Passivhaus has helped build bridges between the natural and industrial materials communities. Yet Macguire’s question anticipates an implicit divide, the degree to which an essentially industrial agenda of synthetic materials as a mainstream norm and the sidelining of the natural materials approach are accepted across sustainable construction.

Along with training and CPD delivery question is a further complication. If passiv principles are fully taken on board, how are they to be delivered? Voices can be heard making about this capacity point. 2010's ministerial announcement by Huhne of wanting every British household to reach Passiv standard energy efficiency there’s been considerable disillusionment regarding what will actually be achieved. This is primarily focused on the zero carbon-housing programme, which is increasingly viewed with a significant touch of scepticism across the sustainable building sector as to the level, energy and budgetary wherewithal will deliver the Governments Green Deal commitment. In April Grant Chapps, minister for Housing, announced revisions to the definition of Zero Carbon, which many interpreted as a serious dilution of standards that domestic buildings had been planned to meet. Again and again, however it’s concerns about the necessary skills of the building sector being up to delivering both post 2013 Part L and the Green Deal, that raise the most concerns. These are issues that bring sighs to the voices of AECB members, both generally and in relation to Passivhaus. Peter Warm point out that Passivhaus is hampered by the lack of a developed supply chain. “There is no interest from the contractors, and while one can convince people at management level, and can talk to the sub-contractors lower down, there is no certainty that these will be the same team who actually do the work. The UK construction industry is led by cost-minimalisation rather than by quality. You always spend a fortune to save a penny.” As to the Green Deal, “I hope we’ll see some good come out of it,” reflects Prewett. “But it could lead to some potential disasters, where the delivery mechanism is so blunt making the situation worse, even if new windows go in.” Prewett’s fear is that real and large amounts of money will be squandered and that the other side of the Green Deal being carried out, a whole lot of defects will have been set off which need to be put right. Prewett is one among many who believes the per house Green Deal retrofit budget of £9000 is too low, leading to defects, and the need for further work rectifying mistakes and problems within a few years.

Model of German architect, Arno Lederer's passivhaus standard museum in
Ravensberg (LRO Arkitekten)
This is the changed landscape the AECB, once a group focused on community and the esoterica of experimental building science, now find themselves operating in. Talk with some of those AECB elders somewhat longer in the tooth, and real enthusiasm is tempered with something approaching weariness about the situation, at times about the infighting and arguments between different factions. But also that they have travelled a long way and there is, of course, no turning back. Much of the old world which the AECB represented has been, or is being, left behind. There was the presence of the hairier eco-warrier builder and architect at the Barbican, but overwhelmingly the uniform was the business suit. What AECB president Chris Baines had called the crafts led construction many moons ago has morphed into a higher tech, computer and calculation led approach to building. The AECB were at the heart of the early seventies and eighties sustainable building culture. This journey symbolises that periods eclipse. You cannot turn the clock back is the choice phrase. Not that they would want to. The reach of influence is potentially game-changing. And there is influence. And also, amidst these hopes and fears there are the buildings. New Passivhaus projects are now cropping up regularly, and do so as well  - another sign of change - in the British architectural media. It’s clear the situation is different to central Europe, where for instance, Vorarlberg’s regional municipality legislation demands all public buildings be to Passivhaus standards and Frankfurt municipality require all primary schools to attain similar standards. It also unlikely to be any – sort of – iconic Passivhaus statements in the UK just yet, along the lines of Arno Lederer, the influential Stuttgart practice, designing the first Passiv-standard art museum for Ravensberg. By contrast the introduction of Passivhaus into Britain, if so far turning out to be relatively small in scale, is set to stay. If, as seems likely, it does and it grows, Passivhaus in the UK will become the symbol by which the AECB, the main sustainable organisation which emerged from outside of the industry building culture, chose to define itself by.