How Architype stopped worrying and learned to love Passivhaus

'A whole family of schools': The emergence of Passivhaus in Architype's Wolverhampton schools.

Architype's London and Hereford offices have embraced Passivhaus big-time. In the aftermath of the Hereford office's award winning St Lukes, this autumn see's the opening of two passivhaus primary schools – the first in the UK - as part of their ongoing schools work in Wolverhampton. Here Unstructured Sitelines tells the story of how the veteran sustainability practice have come to build these first Passiv-schools.

The giant Building Schools for the Future (BSF) programme has been and gone and so, too, has the James (or Capital Report) Review into the new Government’s approach to funding new school building. As generally anticipated the education minister’s Michael Gove’s response has been to head down the pre-fabricated off-the-factory shelf design available route. Up to the point of its cancellation, through BSF, along with capital and other funding streams, some sections of the country’s school estate have been renewed, completed buildings remain very much in the minority. This is particularly pronounced for the primary school estate, with proportionately much larger school numbers; there are 20, 000 primary schools compared to 3500 secondary. Since the BSF programme focused first on renewing secondary schools, attention was only gradually turning to the primary school estate in the last two to three years before the election. What doesn’t seem in doubt is the need, with a significant segment of this estate no longer fit for purpose, that very significant sections of the building stock will require attention for years to come. Gove, while spending much of his first six ministerial months making architects the whipping boys for all that had gone wrong with BSF, by committing to the prefab one-size-fits-all decision, has reinforced the sense that the educational design world is now very much out in the cold, looking in from the outside on the so called education revolution.

What Gove and his cronies don’t focus on is that for a brief period – beginning in the last ten years, though much more intensively in the decade’s second half - there was a genuine gear-shift in school design thinking in Britain. This raised the design bar significantly amongst the involved educational architectural community. If there was very large amounts of money spent on badly designed schools, which there unambiguously was, Gove and the coalescing new educational establishment appear singly blind to some very good design which also went on during this time. And although BSF was mired in problems, in the last year or so the sector was getting a handle on the school design brief. Not only this but, just at the moment the rug was pulled from underneath, a first generation of credible sustainably designed schools were beginning to dot the British landscape. Gove is apparently uninterested in sustainability, and so is unlikely to be aware that this design revolution within the larger schools programme was being driven and led by new primary school designs. For the first time sustainability was part of the design agenda, one which evolved significantly within its brief era of activity, so that by the time of the turning, or swerving, point when BSF et al came to a crashing halt, the potential for a sustainable primary school building estate could be seen to be on the horizon.

Right from early design exemplars such as White Design’s Kingsmead school in Cheshire (2004), a series – a minority, admittedly – of new primary school buildings have been completed which demonstrated, increasingly, a variety of building examples which had every chance of influencing a signally larger shift towards sustainable schools across the country. For instance, the work of PenoyrePrasad, Vermeulen Cottrell, and Walters & Cohen, amongst others, all developed invaluable examples of contemporary primary school design. Last year, with the axe about to fall, new primary schools coming on line assumed an extra poignancy. Projects which were likely to have been pointers to the next chapters of this present day British primary school architectural design, turned almost overnight onto the premature tail end of a public buildings moment. For instance, Sarah Wigglesworth Architects showcase Magna Sandal school in Wakefield, Yorkshire, provided a cornerstone example of what might have come next, before such futures were abandoned. The length of White Design’s journey which had begun at Kingsmead, and continued through iterative evolution’s up to the near present day, was well represented by their experimental Dartington primary school in South Devon, the set of distributed pod-like class rooms providing a vivid example of what a school focused on sustainable holistic education might turn out like. Arguably, however, it is another example which would have been particularly influential in the next generation of sustainable primary school design, those of the four schools designed by Architype West for Wolverhampton City Council, which had begun emerging in 2009 and is in the midst of being completed with the handover of the final two schools this 2011 autumn.

The first of the four is the St Luke’s primary school in the All Saints and Blakenhall district, south of the city-centre, which opened nearly two years ago. Since then the building has received a slew of awards, including the Sorrell Foundation sustainable schools award in October 2010, and a long queue of architectural and educational design visitors. By that time last autumn, what Wigglesworth described as Architype’s “whole family of primary schools,” were just beginning to coalesce into focus. With all four schools completed this autumn they provide a graphic step-by-step illustration of one practice’s evolution towards designing Passivhaus standard primary schools.  It is the introduction of Passivhaus into school design and the energy reduction that comes with the design approach, which underlines the sustainable revolution that these latter schools embody. If St Lukes was a first step, and the contrasting Willows school in Bilston a next one, the two new schools, New Bushbury and Oak Meadow are an arrival point at something new, providing one route map into passiv-standard school building in the UK. And if things had turned out differently on last years election night, one might be looking at rather different horizons for what would be happening with the schools programme. As it is, whatever the future of primary school building, the four school building projects showcase Architype’s particular practice evolution from low energy eco-minimalist design to fully-fledged passiv-design, a journey providing one influential strand in the current ongoing emergence of sustainable educational design.

The schools are all in tough, deprived parts of Wolverhampton and this has inevitably influenced the designs. St Luke’s, as the first of the four, was opened over late summer 2009, ready for the new intake of children in September. Built into a relatively tight site, aspects of the design, particularly extensive use of clerestory’s windows to light up many of the classrooms and internal spaces have been carried over, as part of Architype’s identifiable template, into the two Passiv-schools. Both of these two schools, are two storey, relatively compact builds, with Bushbury also sitting on a sloping ridge-like site. In terms of size and volume The Willows in the Bilston part of the city is the odd school out. The Willows is the amalgamation of two schools, Stow Lawn primary school at its west end and what was the Green Park special school for children with special needs, at the east. With much more land available Architype have designed and built a long and what looks, at first sight, narrow single storey school building to accommodate both schools. In fact, inside the building feels wide and its total internal area of 6742 sq metres encompasses two long parallel corridors each side of the central block of rooms, including three halls and a half-open, carefully landscaped garden. Although commissioned in 2006, at the same time as St Luke’s, as a larger and more complicated project, The Meadows was divided into six phases. Various issues, including community ones concerning the joining of the two schools, challenged the build schedule, so that the primary school end opened in autumn 2010 alongside some of the classrooms for the disabled children. Some parts are still waiting to be used, and the last phase of work, principally landscaping was still ongoing in early summer. While St Luke’s is completely timber clad, Wolverhampton’s schools department was concerned that The Willows school send a tougher signal and included in the design brief a mix of brick and wood to symbolically message that the building wasn’t easy to break into, a kind of tough love building. The same mixed use of local brick – sourced from local Birmingham brick manufacturer, Beggeridge (though since bought up by Wienerberger and UK sourced Douglas fir cladding is part of the Bushbury primary school, where similar issues are apparent, while Oak Meadow returns to the complete timberbuild template of St Luke’s.

St Luke’s is the forerunner and its earlier design period is reflected in the design approach, one where Architype hadn’t as yet fully taken on board the Passivhaus approach. Still, Architype have long been among the forefront of established sustainable practices in the UK, so when it came for St Luke’s to be tested for its BREEAM rating in 2009 the fact that the school achieved “excellent’, becoming the first primary school to do so, wasn’t perhaps a complete surprise. At the time the Architype West Office, based near Hereford (the original Architype office is still in London), were in the middle of working through their thinking in relation to Passivhaus. St Luke’s reflects the general practice philosophy of designing to minimise the energy needed to run buildings, drawing down the energy and performance footprint without recourse to renewable kit; the eco-bling in Gaia Architect’s Howard Liddell’s memorable phrasing; tech which may look good, even if its presence is to mitigate a buildings heavier footprint. To attain the BREEAM rating the buildings plan was designed to optimise light and ventilation while minimising the energy used across the building. This meant that the different class, staff and admin rooms, along with the open spaces were carefully modelled to ensure as low as possible energy use and carbon emissions. At the same time the schools heating is run through a biomass boiler system, with gas back-up, at the time, the generally accepted low energy system.

By the time that St Luke’s was being completed, however things were changing, with the West office wising up to Passivhaus. They were also going through a rethink on the orthodoxy of biomass a central (if distributed) source of energy. One of Architype’s key outrider’s, Nick Grant of Elemental Solutions (www.elementalsolutions.co.uk), who has had a long working relationship with the architects - historically developing natural drainage and waste systems - travelled to the 2007 Passivhaus conference in Bregenz, in the Vorarlberg region of Austria. Grant set off for Austria with his mind half-ready to dismiss the newfangled Passivhaus fashion emanating from central Europe, but came away, after seeing a series of built projects, a convert. “I travelled to Bregenz with half a mind at debunking it, but came away pretty convinced. Part of it was seeing actual buildings, and the rationality of the process. I was impressed by how it was conceptually sophisticated, though also very simple, and realised that actually there’s something in this.” The conference seems to have turned the heads of the small though committed British contingent of 13 who travelled there and the realisation that all over the continent hundreds of architects, engineers and builders, particularly in the German speaking countries, were developing Passivhaus principles, not least the high priest of passive culture, professor Wolfgang Feist, founder of the Passivhaus Institute.

Returning to Britain all fired up, Grant ordered the Darmstadt based Passivhaus Institute’s PHPP modelling programme and once it arrived, began to teach himself the programme. Having mastered PHPP, Grant began showing others within the West office both how the programme worked and underlining the potential benefits, along with familiarising them with Feist’s Passivhaus Institute. Grant could see that Architype’s signature low energy approach, with  “glulam structures shooting through the walls,” would require a step-change in design, moving towards an air tight box design, with the focus on plugging the leaks, including removing all thermal bridging. At a presentation to the studio team he summarised the case for Passivhaus. “There was a lot of flack”, Grant recalls, though also acknowledging “an open receptivity to a system,” which many could see worked. Not only this but the passive system slotted into Architype’s ‘eco-minimalist’ philosophy. Indeed West offices founder Jonathan Hines was quickly drawn to Passivhaus, seeing an unbroken line from Architype’s early Walter Segal houses right up to Passiv techniques, with both ends falling within the practices slogan-like ideological cry of ‘letting the building do the work.’ Having recently won a tender to prepare designs for a new library in Ledbury, the office tried out the PHPP programme on the designs that were developed. There were some difficulties, and then the library project stalled, before disappearing altogether. By this time a tranche of primary school work had come Architype West’s way, including Staunton, a primary school in their local Herefordshire area, plus St Luke’s and The Willows in Wolverhampton, and another possible school in Leeds; Swinnerton. The practice was by now swinging towards the passive principles of focusing on performance rather than emissions. By spring 2008, Hines accompanied Grant and others to the next of the annual continental Passivhaus conferences, this time in Frankfurt and was able to check out a group of buildings himself. What is more these included schools, as Frankfurt is one of the German cities leading the development of passive-schools.

Six months later, by the time of the Association of Environmentally Conscious Builders, AECB) autumn 2008 conference, the office was pretty much converted. During the second half of the decade the AECB network had been instrumental in raising awareness about Passivhaus, with two members, David Olivier and AECB CEO and architect, Andy Simmonds, particularly involved (see the main Passivhaus overview piece.) There are overlaps between Architype, Grant, and others in English-Welsh borders network, with the AECB, the latter having maintained a radical, even militant, critique of organisations such as BRE, those officially charged with developing energy and emission building performance policy and regulation, So Architype’s receptivity to Passivhaus’ more radical performance standard isn’t a complete surprise. “We bought into it very quickly,” Mark Lumley, the partner responsible for the current two Wolverhampton schools, says now. The mix of building physics, building performance and thermal comfort, fitted well with what he describes as, “Architype’s vision of reducing consumption.” They were also getting more familiar with the Darmstadt Institute’s PHPP programme.

During this same period Architype were also re-thinking their stance on biomass. With the upsurge of, or dash for, biomass gathering speed, Grant was commissioned by the AECB to research a discussion report on biomass, and its place in the suite of emerging zero carbon strategies. The resulting policy document rehearses what remains a contentious argument; that biomass - essentially burning wood for energy - was a net carbon emitter rather than a net carbon reducer. That’s putting it very simply, and within circles who’ve read the report, such as the AECB membership, it proved, unsurprisingly, controversial. For some Grant, along with professional partner Alan Clarke’s, case against biomass wasn’t as black and white as they were portraying. Others argued that it was plain inaccurate. But at the West office  (which when I visited in 2007, was very excited about showing off a then newly launched and only nascent biomass network initiative in the Hereford area, one which could fuel the new studio’s biomass boiler) the perspective on biomass also changed. If this core part of a renewable energy source was being thrown out, what was there left? Right on time, the passive Fabric-First approach answered that question.

Aspects of the biomass debate fed into Architype’s work on the Wolverhampton schools, though St Luke’s includes a biomass boiler, and The Willows features a stand-alone energy centre. What the debate underlined for the practice, however, was that any definite path committed to upping the energy performance of buildings, without the compensatory effects of renewables, and now also biomass, required travelling the Passivhaus route. What they needed were projects to test the approach effectively, and draw it into their sustainable methodology. After the false start of Ledbury library, Staunton’s Passiv dimension on hold, and the Leeds project mired in bureaucracy, they weren’t really sure how it would happen. But then, of course, it did.

In Wolverhampton the city councils school building programme had resulted in a couple of problematic new schools designs. Unhappy with the plans, the councils building department approached Architype, and asked, on the back of the success of St Luke's, whether they'd like to make a revised bid for these schools. This was the opening that Architype had been waiting for; they could use the schools as testing grounds for the learning curve of Passivhaus knowledge. The way Lumley recounts it today, it sounds as if Architype jumped at the chance. Ready to design the schools to passive principles, they put the proposal to Wolverhampton's council team. Interested, Wolverhampton's team went away, thought about it, and came back with a yes. There was a sticking point, and not too surprising one at that; both buildings had to be delivered to the same budget as the first architects planned schools, and within a shortened timeframe which demanded the schools be ready to open at the same time as the original architects schedule, September 2011. Confident that the team they'd put together for St Luke's and The Willows had worked well together with Grant and Clark as Passivhaus consultants, engineers Price & Myers, landscapers Coe Design, E3, the mechanical and electrical engineers, and Stourport based builders Thomas Vale and Co all up for the challenge and in can-do mode, Architype swallowed deeply – and signed up.

That was in the summer of 2010. When I visited the two school sites in summer 2011, with five to go before opening both schools, both Bushbury Hill and Oak Meadow primaries, are well on their way to completion. The tight time-frame has meant substantial learning on the job for some of the team. Putting on safety gear before heading into the Bushbury school site with Lumley, head of the Thomas Vales team, Simon, nods a somewhat wide-eyed ‘yes,’ when I ask if the learning curve has been vertical. Lumley’s words are only warm towards the builders, however, saying the company have been ‘very solution oriented’, believing that the two buildings wouldn’t have happened without Thomas Vales participation. Coming in at £4.5 million and £5.2 million respectively. Bushbury is on a smaller, sloped site and the resemblance to St Lukes, at least as a template, is more pronounced. The same template influence can be seen at Oak Meadow, although Lumley notes that Oak Meadow is both trimmer and shorter.

Both buildings apply Architype’s timber-frame template, which has evolved over the years, the result of considerable accumulated knowledge. At heart the template is a continuation and refinement of the Walter Segal self-build timber-frames with which Architype initially began their architectural journey. St Luke’s is arguably the pre-Passivhaus culmination of that journey, Howard Meadowcroft, one of Architype’s older hands, and who has been centrally involved in the evolution of this timber frame story, suggests in an email, the first of the Wolverhampton primary schools is, “our most successful project because it builds on the spine of work that has developed since the start of the practice.” Meadowcroft has helped with turning this knowledge towards the Passiv direction, partially from the experience of working on an earlier Passivhaus project he helped design for Andy Simmonds, (one half of SimmondsMills and one of AECB’s stalwart activist members) while on sabbatical from Architype.

As befits Passiv buildings, Oak Meadow and Bushbury are more technical buildings when compared to St Luke’s. The main focus of their technical dimension relates to the performance issues that passive buildings require. Given Passivhaus is about guaranteeing air tightness of the complete surrounding fabric, the focus is on the walls, the doors and the windows and their multiple layers of insulation wrapping around the sides of the walls. The timber wall is reinforced with 240 mm of Warmcel insulation.  Lumley emphasises that the critical air tightness is in the OSB barrier – 18 m of OSB. Fermacell has been used for primary insulation, though on the inner and not the external walls. Tests for air-tightness flows and leaks, run by Grant’s Elemental Solutions, all passed comfortably, with blower door test easily surpassing the Passivhaus target of 0.6 air changes. Elemental Solutions have been working on an adapted ventilation system developed with E3, used, according to Grant, in a new and innovative way, as well as running professional workshops on Passivhaus principles for the various contractors with a focus on details to ensure that achievable air tightness isn’t compromised.

The highly insulated doors and super-triple glazed window systems remain a niche market for the level of insulation required of Passivhaus, with suppliers and producer only beginning to be appear in the UK at present. Much of these high-grade windows, airtight window joinery and doors continue for the present to be imported from middle Europe. They are also a relatively hi-tech contrast to the lower tech timber-frame structural design. What does need to be done when building to Passivhaus standards, Lumley reiterates, is to ensure everything is in order right at the outset of the construction. Mess this up and one might as well begin again. This imbues a certain further level of rationalism to the design both of the whole design, and of the need to design all the different parts in parallel; in effect a more developed level of complexity. Lumley’s words here are an ‘holistic approach.’

To supplement all this work in drawing the energy levels down to the minima, Lisa Pasquale an Oxford Brookes graduate researcher working out of Architype’s office, is helping to draw the footprint even further down. Pasquele is carrying out a collaborative POE research funded by the Technology Strategy Board, and is sending through live updates with the aim of improving the energy performance of these two schools. Recent recommendations include lo audit and reduce the energy of lap-top use, and the monitoring of lights and other electrical services that can be inadvertently left on.

Since both Bushbury and Oak Meadow are in areas of severe deprivation both feature extra dedicated facilities for the Multi Agency Support Teams (or MAST), spaces essentially for social services, police and other visiting professional services, to cope with various children who are at risk, or already under protection orders supervision. These include a small meeting room with space for 30 people, two small interview rooms and a soft lounge/family room and kitchenette. In both buildings these have been situated on the north face of the schools. As something of a contrast Oak Meadow will also contain sound recording facilities up on the second floor as part of the schools performing status.

Late in the afternoon I visit, thinking about Wigglesworth’s ‘family of schools’ phrase, I ask Lumley, how he would describe the relation between the four schools; different or the same generations, siblings or cousins? Siblings, he answers, continuing that these younger brothers or sisters, contain the same characteristics and forms of their older siblings, including their own kind of struggle, though less of a struggle, applied in their own particular way. When I met Hines some months ago to talk about the practice he talked about the Sorrell Foundations award and how Sorrell talked of the ‘quiet voice of Architype’ winning through. He could imagine more showy school buildings, which could have won, though thought they would not be there in thirty years time. He was adamant that this wasn’t the case with Architype, and that St Lukes and others of this Wolverhampton family of sibling school buildings would be there in thirty years time. He was also confident that they would be doing so, while requiring a fraction of the energy to run of their school building peers. It may not be anything like the scale of middle Europe, where for instance, Passivhaus schools are an increasingly common requirement, but in Britain where change is running perhaps fifteen years behind these continental peers, it’s both a significant signal and contribution to the interrupted evolution of the country’s first generation of sustainable schools.

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