16 minute read
It’s all architecture to us
Jon Wright and David Hills discuss how dilemmas raised by 20th-century buildings are influencing established philosophies on the conservation of buildings from earlier periods
No century has left us a more varied set of conservation challenges than the 20th century.
A vast array of new styles, alternative technologies and materials, plus diverse intellectual and creative forces have left behind a tremendous architectural legacy. Caring for that legacy and bringing equivalence to conservation efforts is a continuous intellectual and practical debate – with consensus often hard to reach. For Purcell, the question remains consistent: how can we, as architects, masterplanners and heritage consultants, assess and respond effectively to buildings of the 20th century and, in the process, bring parity to our conservation efforts on buildings of all periods?
Purcell’s commitment to improving conservation assessment and architectural responses to 20th-century buildings is manifest in recent projects and engagement across the sector: we work with communities and specialist groups to share knowledge and bring new ideas and fresh approaches to these buildings. Purcell is the first practice to have convened a 20th-century group, creating a forum allowing like-minded people throughout the sector to share information, expertise and illustrate projects. Our collaborative philosophy arises from a unique make-up that aligns the critical interpretation of the heritage consultant teams with the creative pragmatism of the project architects. For 20th-century buildings, we believe that understanding place, design intent and nature of fabric is paramount if we are to avoid mistakes of the past and define new modes of conservation for the future.
Balancing tangible and intangible significance
As with buildings of any period, the tangible fabric of modern architecture – concrete, steel, plastic and glass (among other things) – comes with range of intangible values. Objectively, this should present no problem for assessment, as long as those values are expressed fully and reflected in the conservation response.
Modernism was a departure from earlier architectures; it forged new forms, overturned old conventions and created unfamiliar new spaces and places through progressive ideas about how to live and how to recalibrate our buildings to a changing world. It was the first truly global architecture, spanning the central decades of the 20th century and evolving into a diverse series of languages that valued similar conceptual and artistic themes. The intangible qualities of Modernism are therefore related to design intent, artistic expression, the purposeful reflection or rejection of context, and the relationship of the building to international movements. Projects for listed and unlisted 20th-century buildings over the last decade have failed to properly address these intangible aspects, resulting in outcomes that do not represent conservation – partly due to the lack of an agreed approach.
In 2017 the International Council on Monuments and Sites’ 20th-century committee, ISC20, ventured the first international standard, Approaches to the Conservation of Twentieth Century Cultural Heritage: Madrid–New Delhi Document. This milestone has formed the basis for much recent work by Purcell; awareness of international best practice, scholarship and evolving our own expertise are the key ways we bring consistency to our approach to modern buildings.
Valuing judgement
Listing has had to evolve to accommodate modern heritage. The latest thematic survey on Postmodernism added 17 buildings dating from the 1970s and 80s to the list, and more will follow. These, and those from preceding post-war decades, pose fundamental questions about heritage protection at a time when clarity is needed about what is being valued and why.
At the National Gallery, as masterplanners and designers of new gallery spaces, Purcell recognised the importance of the Postmodern extension by Venturi Scott Brown & Associates. This was expressed before the decision to list, bringing assuredness to the process of change. We assessed the building as part of the wider international movement, recognising its listing potential.
Dr Gabriele Finaldi, Director, The National Gallery
Axonometric of Liverpool Metropolitan Cathedral
Liverpool Metropolitan Cathedral
At the Natural History Museum, Purcell completed the first enhanced listing for a landmark building. A Statement of Significance positioned the 1970s Palaeontology Wing in its full architectural and historic context, comparing it with similar buildings of the period and other projects by the Office of Works architects who designed it; it was the first proper study of either. The resulting enhanced listing set a hierarchy of value within the site, with the 1960s extension not considered to make an essential contribution. This has provided a greater understanding of potential for change, including removing a section to make way for a progressive Niall McLaughlin scheme that will undoubtedly be valued in years to come.
At St Fagans National Museum of History, Purcell collaborated with Cadw to establish a new designation for the site, followed by a conservation management plan – bolstered by an interview with project architect John Hilling – that established heritage value and offered guidance on a scheme to reinvigorate the museum. Purcell’s work encompassed repairing the original fabric, reinstating the architectural concept, and carefully siting new buildings that retain the structure’s profile and leave intact the important landscape. Purcell’s approach delivered the model project – one that navigated all stages of the process, from listing to completion. As Purcell partner Jamie Coath explains: ‘Having a direct engagement with Hilling was a really rewarding, and rather unusual, opportunity to fully understand the original design, enabling us to confidently assess the significance and respond appropriately with alteration and enhancement proposals. It was a proud moment when he visited the site on completion of our work and was glowingly positive about the result.’
Articulating significance and achieving consensus
At the heart of conservation practice lies the concept of significance – that overarching theoretical umbrella that shelters historic buildings from the ‘acid rain’ of poor conservation. A range of guidance and legislation is used to define value: the evidential, historical, aesthetic and communal, countered by technological and spiritual values, remain the most common to articulate what makes buildings and sites important and define the parameters for heritage impact. Some have questioned the system’s fitness for purpose on 20th-century buildings, calling for a new framework that better addresses their unique qualities. In time, we may alter the rubric for assessment, but that’s unlikely to happen soon so better recognition of the current framework to deliver successful conservation is required.
Purcell has placed a complete understanding of significance at the heart of our architectural response, pushing the boundaries of the current system to account for the site’s architectural theory, historic context and material culture. Of note was how we addressed the complex significance of the Grade–II* listed Liverpool Metropolitan Cathedral (1967) by Sir Fredrick Gibberd. Recognising the Gesamtkunstwerk nature of the architecture and layering the significance of the artistic, structural and architectural elements of the building under common headings, the assessment linked the significance judgements directly to a series of prioritised conservation actions.
To mend Modernism, we must understand it first; we must step beyond any reductive tendencies and ask the fundamentals: what is important about this site? Why is it the way it is? What are the active drivers in its design? What actions will deliver proportionate conservation responses?
St Fagans National Museum of History
Courtesy of St Fagans National Museum of History
Martyn Evans, Estate Development Director, The Dartington Hall Trust
Battersea Power Station has proven to be fertile territory in advancing Purcell’s conservation approach. This massive undertaking enabled the often-claimed but rarely practised collaboration with regulatory authorities through the setting up of a conservation steering group. This provided a regular forum and enabled each stakeholder to present their concerns, share expertise and debate openly on all issues from design through construction to future maintenance. Meeting monthly since 2013, it has provided consensus on what is significant about the building and, crucially, what is not. This is vital for a project of this size and complexity, and to manage the level of intervention needed. Ultimately, the approach transcends the conservation status quo; the welfare of the asset is based on a tacit understanding among all parties, paving the way to experiment in the approach to the building fabric and its protection.
Building on this mutual trust, Purcell has developed heritage partnership agreements that tackle the complexity of applying heritage protection to a large building with multiple occupiers, each with a different agenda. Here the starting point has been to break the building down into functions and spaces, articulating the significance of the fabric in each, and using this to determine a series of interventions that negates the need for repeated consents. This synthesis of articulating significance with best-practice fabric repairs signifies a brave new world based on mutual understanding and respect for the monument and what each party needs to get out of it – an approach that has relevance to buildings of all periods.
London's Cathedral of Industry - Battersea Power Station
Purcell
The difference with Modernism: assessing theory
The notion of ‘otherness’ continues to bedevil conservation projects for modern buildings. The fact that Modernism was inherently different in its theory and construction has meant that arguments for alteration from many quarters have been given undue latitude: It failed! It was only meant to be temporary! The architect had to change their design! It never worked properly! It can’t be converted! It’s the idea that’s important, not the fabric! It’s the fabric that’s important, not the idea! These arguments have never applied to listed buildings before, so why now? In parallel, whether the ideology behind the building – be it social, political or architectural – is embodied in the fabric, and can therefore be preserved, is also moot. Here lies the intangibility of Modernism so often misinterpreted in the past – the relationship between building and landscape, contextual links and international movements and the artistic expression inherent in built form. If these are not ingrained in conservation efforts, responses will be unsuccessful.
Undoubtedly there may be totally ‘new’ situations that call for pioneering solutions. At Liverpool Metropolitan Cathedral, Purcell has devised conservation techniques for dalle de verre, the technique that places pieces of coloured glass in a matrix of concrete or epoxy resin. This is the epitome of the kind of research and development that permeates Purcell’s work. Using funding from the Getty Foundation, we explored the importance of various aspects of built fabric and developed a repair technique based on traditional approaches, updated to meet the specific needs of the building.
The lantern – which forms the structural, spiritual and artistic crown of the building –has been beset with problems since completion: degraded by weathering, the resin holding the coloured glass hardened, causing fractures and water ingress. Previous repairs had introduced flashings and mastic sealants, affecting both performance and aesthetics. In this instance, there was no precedent for repairs. However, rather than searching for a ‘new’ solution, established conservation principles were the starting point, informed by a conservation management plan that attributed high significance to the original fabric, dictating an approach of maximum retention using repair resin based on the original mix. Now, after a history dogged by notions of failure and inappropriate conservation, Purcell is repairing the mistakes of the past, providing this pivotal piece of British Modernism with the appreciation it so richly deserves.
Purcell’s design ethos arises from the same place as that for restoration and repair. At Arne Jacobsen’s 1962 Grade-I listed St Catherine’s College in Oxford, the college motto Nova et Vetera was expressed by Jacobsen, who married modern materiality to ancient plan form with primary and secondary grids to deliver a complete work of art. Following a diligent assessment of significance and historic development, Purcell responded with a new accommodation block, delivering modest, calm buildings that complement the scale and mass of the existing structures. The new graduate centre exploits its slight geographical removal to boldly reflect Jacobsen’s interest in pure geometries, artistically reflect the grids and reference the Oxford typology of the circular plan form. Understanding does not necessarily mean constraint and, here, expressing some fundamental drivers in Modernism has resulted in a bold, expressive piece of new architecture.
The House of the Future
Courtesy of Danish National Art Library, Copenhagen
Honesty is (still) the best policy…
Our work on a series of iconic modern buildings has prompted us to look at how the hard-won philosophies and principles gained from our work on earlier buildings might guide us on later work and vice versa, informing our approach to all architectures. ‘New’ approaches have not always delivered successful outcomes. As the first wave of conservation of modern buildings comes of age, the undoing of previous repairs is increasingly a feature of our work.
William Lescaze’s 1932 Grade-II* listed High Cross House in Dartington, Devon, is effectively a living sculpture that happens to have rooms within. This international-style house is about surface and line, which has been eroded by a series of well-intentioned, but ultimately disfiguring, interventions: coping stones introduced to parapets where previously there were none, crisp facades interrupted with flashings and weepholes that would never be considered for earlier buildings. Purcell aims to return the purity of the original design, stripping accretions in pursuit of minimal interventions that, perversely, now require much intercession. The building may have been influenced by many forces but, ironically, has been most affected by conservation. We are ensuring we do not perpetuate mistakes made in the past.
At the Grade-I listed De La Warr Pavilion, Purcell has been exploring the potential to replace the badly corroded galvanised steel glazing of the iconic south window with bronze. One of the most recognisable symbols of international Modernism, research indicates that Chermayeff and Mendelssohn, recognising the issues presented by the seafront location, had intended the windows to be bronze but were constrained by the budget. This synthesis of theory and fabric repairs has the potential to realise the original vision while solving an issue that has been ongoing for many years.
Repairs need to respond to the original design intention; ours is a duality that sits theory alongside fabric as part of a holistic conservation strategy. Often the ‘honest’ repair approach has been misapplied on modern buildings – at Battersea Power Station, Gilbert Scott’s celebrated facades are of the highest significance; the distinctive stepped profile and fluted details break down its vast bulk into a delicate interplay of light and shadow, solid and void. Previous patch repairs to the huge expanses of brick upset the clean lines and impacted on this significance. In this context, Purcell felt the most ‘honest’ thing was to blend in the repairs, remaining true to the original design intent. To achieve this, the selection of new materials to match the existing needs to be exemplary. This led to a like-for-like approach, sourcing from the original brick suppliers and developing forensic-like techniques for producing bespoke blends – techniques we have since employed on buildings of all periods. Similarly, at St Fagans, replacement calcium silicate bricks were sourced from the original suppliers to ensure a continuity of appearance to the repaired building.
Concrete came into its own in the modern age; the technology used to repair it may be different to that for ‘traditional’ materials but the like-for-like principle has remained consistent in Purcell’s approach. At St Fagans we eschewed the ‘new’ convention of using proprietary mortars and coatings in favour of a bespoke mix of aggregates, binders and stone dust that matched the texture and colour of the original concrete to give a seamless repair. At Battersea Power Station this was taken one step further by fabricating new pre-cast units to match the existing ones, working to the building’s natural junctures to invisibly insert new elements that were ‘weathered’ in situ to match the adjacent original fabric. This materials choice was, again, prompted by our work on traditional buildings – we wouldn’t use a different material for repairs to those structures so why would we do so on a modern building?
Back to basics: continuity, ancient and modern
Modernism may not be as simple as it looks but caring for it need not be complicated. The solutions to some of the issues facing 20th-century buildings, whatever their theoretical and material make-up, lie in the recalibration of our existing conservation strategies and the proper application of knowledge on how to care for architectural history. Purcell’s approach is about evolving complexity in understanding significance, but this doesn’t preclude a back-to-basics approach to fabric repairs.
The recurrent theme throughout Purcell’s physical conservation work on modern buildings is assessing each case on its own merits and developing new techniques where appropriate, but doing this through a lens of tried-and-tested conservation philosophies and principles, adapting them to suit individual circumstances and materials. That we have reached this position owes itself to a process of careful understanding, having gone full circle to get there, learning from the mistakes of the past. Adopting and adapting existing principles creates a continuity with conservation practice past and present, bringing with it invaluable information and equipping us to deal with the future challenges.
Articulating the various significances of 20th-century buildings and sites, and expressing them, still needs critical attention from heritage consultants and architects alike. The level of sophistication in categories of significance currently operating as an industry standard are, perhaps, an easy target and could be better, but that masks the real issue – that a broad understanding of what is important about these buildings has not yet filtered through. It may not be about changing the framework but, rather, properly applying the rubric we already have.
Purcell is investigating, innovating and collaborating with others to ensure the incredible built legacy of the recent past endures into the distant future. What sets us apart is an evolving, informed understanding of place – strengthened by the confidence to question past decisions and current philosophies. This delivers more sensitive and thought-out responses, bringing parity to our conservation efforts regardless of period. It’s all architecture to us.
High Cross House at Dartington
RIBA Collections
House at Dartington in Devon, where Purcell is reversing previous conservation efforts to bring the original house back to life
The incomparable De La Warr Pavilion
RIBA Collections
