8th December 2020

Perega Clear Structures answer artist’s prayers

Arabella Marshall is a well-known, Suffolk-based artist who specialises in glass installations. One day, walking in the vicinity of RSPB Minsmere, situated on the county’s windswept coastline, she came upon the striking medieval ruins of Leiston Abbey. She was inspired to use the location as the setting for a stained glass sculpture.

Influenced by Minsmere’s thriving yet vulnerable natural environment, the piece, which would be named ‘A Wing And A Prayer’, also cleverly and playfully references the building’s original ecclesiastical purpose.

To help bring her project to life, she commissioned our Southend-based Perega Clear Structures office, where our team provided recommendations relating to the framework. This ensured it could withstand the temperamental elements of its coastal setting.

It was an unusual request, and very different from the day-to-day commercial and residential façade and balustrade commissions our team receives. Further, it presented some very specific structural challenges, particularly as the sculpture was composed of what is known as ‘fused bullseye glass’.

Fusing is a traditional method for making the glass used within stained glass windows, achieved by melting layers of glass on top of each other in a kiln. This technique would have been used to create the windows for the Abbey in its middle ages heyday.

The type of material used for the process is known as ‘Bullseye Glass’, and its properties differ significantly from the engineered formats which our team regularly work with. This meant those involved in the project had to do extensive research to work out the properties needed to design a structural solution. As such, the approach to this project had to be highly nuanced also taking the location’s unpredictable weather patterns into account.

Initially, the plan was to have the sculpture as two separate pieces of glass suspended within its framework. However, this was changed during the design by Arabella and it evolved into three parts, to provide a more striking visual appearance.

As well as providing glass specifications relevant to the use of fused bullseye glass to achieve this, the Perega Clear Structures team also provided a design and specification based on the use of a modern toughened, laminated glass, as an alternative was required for the art piece.

Guidance was also drawn up to inform the artist of the detailing she would need to consider when building the pieces’ framework. These consisted of typical fixing details to Leiston Abbey’s structure, including what the fixing reactions and loads would be. This was then passed to a local steel fabricator who worked according to our recommendations.

Further employing our extensive knowledge and little black book of highly-adept construction partners, our team also put Arabella in touch with local glazing contractors Estuary Glass & Glazing, who installed the glass within the frame to realise the project.

Commenting on ‘A Wing And A Prayer’, project lead, Rob Parsell says, “This was an enjoyable project to be involved with and really tested our creativity as the type of glass involved is rarely used for structural purposes. One particular challenge was establishing what we could take for the fused glass’ design values because specifications and data for this type of material is rare. This is due to the fact it is more commonly an artisan product made in-house by the artist or craftsman. Ultimately, we worked according to yield values, limiting the stresses present in the panels so they would be similar to those in normal glass.

The results speak for themselves. From a professional perspective, I loved that this was something completely different from the norm. It’s the type of job which structural engineers live for, a unique problem requiring an imaginative solution. Personally, I think the finished sculpture looks fabulous, an attractive and evocative asset to the locality.”

To find out more about Perega Clear Structures projects, visit our “Glass and Facade Engineering” page.

Photos credit: Tim Curtis