Successful Completion of Uniquely Intricate Listed Roof Replacement

THE SUCCESSFUL completion of a unique and intricate listed roof replacement has been concluded by Midland’s contractor, G F Tomlinson.

The project involved removing the original roof from the iconic Grade II Listed Central Building at the Castle Meadow Campus for University of Nottingham.

As part of a comprehensive £100 million refurbishment to extend the life of this architectural city landmark, the original PTFE (polytetrafluoroethylene) roof has been replaced with a modern tensile structure, the latest generation in PVDF fabrics.

Originally designed and installed in 1994 by Hopkins Architects and Arup, the roof is described as one of the most complicated roof structures in Europe.

Prior to G F Tomlinson starting on site, the building was given a Grade II Listed status and at 30-years old is one of the youngest buildings to achieve this. This presented additional challenges to ensure the heritage requirements were met, whilst adhering to the original refurbishment needs.

Uniquely Intricate Listed Roof Replacement

The building’s entire framework has been carefully refurbished to preserve its structural integrity and historical significance – a process which began mid-2024, with the removal of the building’s glass elements, repainting of the structural frame and refurbishing of key components.

Temporary rigging and birdcage scaffolding were installed to stabilise the frame, while sections of the roof were removed in sequence.

Starting with the north and south sections, followed by the main roof central section with its three floating oculi (circular openings) the east and west portions were finally removed.

Structural strengthening, including additional welding and the replacement of worn components was carried out before the placement of the new fabric.

The project continues to progress, with the installation of a new glulam mezzanine floor to enhance the building’s functionality and a new central glass roof box to ensure plenty of natural light into the building.

The final stages will include installation of new laminated glass to the roof, designed to meet modern building standards.

Exceptional Engineering Feats

This project has involved exceptional engineering feats – the new roof spans approximately 4,500m², equivalent to the size of seven tennis courts.

The scaffolding used as a working platform for the replacement weighed 60 tonnes and stood seven meters tall, covering a platform area of 945m².

Over 5,000 bolts were removed and replaced, while 15 tonnes of existing glass will be reinstalled, complemented by an additional 4 tonnes of new glass within the facade.

These significant works have been delivered in collaboration with Bond Bryan Architects and Arup Consultants.

Specialist contractors, Base Structures have been responsible for the fabric replacement, with Novum Structures installing the glass box and internal glazed rooflights, blending innovation and heritage.

Adrian Grocock, Managing Director at G F Tomlinson, said: “The Central Building project is a perfect example of how we combine innovative construction methods with heritage expertise to deliver transformative projects.

“The roof replacement represents a significant achievement, and we are proud to be playing a key role in extending the life of this iconic structure.”

Fraser Shirley, Director and Project Manager at Base Structures, said: “Having built many of the UK’s most notable fabric canopies Base Structures fully appreciated the significance of this elegant and refined structure. The integrated tensegrity design was one of the first of its kind, making this a truly unique project.

“The fabric replacement works on the Central Building was far from straightforward, presenting an incredibly challenging task as the original builders had never intended for it to be replaced. Due to the sensitive nature of the structure, a meticulous and carefully planned methodology was essential to minimise excessive loading on its components.

“Significant input from Tensys Ltd was instrumental in developing this approach. The success of this project was ultimately down to the vast experiences with the Tensys and Base design, project and site teams, who in collaboration with the main contractor, G F Tomlinson, carried out the works safely and seamlessly, ensuring the structure’s integrity was maintained throughout. Base Structures are proud to have played a part in extending its lifespan.”

The university is displaying some of the original structural parts of the building at the Castle Meadow Campus to showcase the architectural elements and to preserve the legacy of the building’s original design.

>> Read more about more roofing projects in the news