As modernist buildings join the ranks of our built heritage, we need new approaches.
Building conservation has traditionally focused on protection of historic and architecturally important fabric and adoption of minimal intervention approaches. What happens when a more intrusive approach is needed? Will this be detrimental and can it be justified? These were the questions faced by Historic England, The Twentieth Century Society and the design team working on the Grade II* listed Congress Theatre, Eastbourne.
The Congress is one of only a handful of UK post-war listed theatres, and an excellent example of a modernist building of national importance becoming a heritage asset. Its architectural merit puts it on the same level as the National Theatre, Royal Festival Hall, Nottingham Playhouse and Chichester Festival Theatres.
Built in 1963, the 1,689-seat Congress is the largest theatre on the south coast. Modernist architecture makes notable use of reinforced concrete as sculptural forms and as artistic elements. The Congress had a reinforced concrete-framed structure with concrete mullions and transoms on the glazed façade.
The Congress is one of only a handful of UK post-war listed theatres, and an excellent example of a modernist building of national importance becoming a heritage asset.
In 2010, a section of concrete fell from the front of the theatre, signalling the need for major repairs. A harsh chloride rich marine environment and poor technical detailing had led to the gradual degradation of the concrete and corrosion of the metal reinforcement, making the concrete unstable.
The owner, Eastbourne Borough Council, erected protective scaffolding around the building to ensure safety while seeking advice from structural engineers on the best way to restore the theatre to its former glory. This project was at the forefront of concrete conservation, a specialism with which the industry will become more familiar as 20th-century buildings continue to age.
In 2014, Faithful+Gould was appointed to undertake the restoration, which was closely monitored throughout by Historic England. Our role comprised lead consultant, project management, cost management and heritage consultancy.
The £1.65m project began with identification of the building’s importance and significance. We concluded that, like many modernist buildings, the theatre was important not because of the age of its materials, but by virtue of its aesthetic value and architectural design. Our aim was therefore to conserve aesthetics, retaining the façade’s original appearance, as well as making the building sound.
Where applicable, we expect to see this approach become more common as 20th-century buildings require increasing repairs and maintenance.
Heritage impact assessments were carried out, to explore whether minimal intervention would be sufficient. Previous repairs had failed as the theatre continued to deteriorate and, following robust exploration, we determined that further repair would detract from the building’s appearance. In a departure from traditional conservation approaches, we proposed removal of sections of the building’s fabric, stripping it back to the principal structure, and replacing it with modern materials. These offered a robust solution to the hostile conditions of the local marine environment.
The decision to select an intrusive methodology was not undertaken lightly, as respecting the appearance, restoring the materials and preserving the unique details have long been the drivers for heritage projects. The Congress’s challenges certainly highlighted the dilemmas posed by conservation of these 20th-century structures.
However, with strong support from Historic England, the team was able to justify the plan to maintain the aesthetics of the façade by wholesale replacement. Where applicable, we expect to see this approach become more common as 20th-century buildings require increasing repairs and maintenance.
Much has been achieved with the use of contemporary techniques and materials, successfully matching the original features and protecting and preserving unique modernist heritage. The eight supporting concrete columns were repaired, using the latest technologies, such as impressed cathodic protection, where an electrical current is pumped through the structure to prevent corrosion. At the Congress Theatre, this was an appropriate solution and a relatively less invasive process, minimising physical impact on the structure.
Much has been achieved with the use of contemporary techniques and materials, successfully matching the original features...
To avoid a patchwork of finishes, all the original decorative concrete panels were replaced, using modern techniques to match the original features accurately. The slate cladding also needed attention to detail and we tracked down the original quarries, enabling accurate replication.
Sensitive installation of specialist glazing and replacement of window frames has contributed to both the aesthetics and the performance of the building.
The theatre remained open during the repairs, which precedes an exciting £8m internal refurbishment, commencing in early 2017. The project exemplifies the high-quality conservation leadership Faithful+Gould brings to a wide range of projects.