In a rededication ceremony that coincided with the annual Walking Day procession in 2019, the gates were welcomed back to the town following an extensive restoration project that was overseen by Ramboll’s specialist heritage and conservation team.
The restoration is a testament to 21st Century techniques and technologies which, combined with traditional skills and thousands of man hours removing corrosion, re-painting, casting, forging and fabricating new components, have carefully restored this structure; a 19th Century exemplar of Coalbrookdale’s abilities in cast iron.
21st Century technologies and techniques enabled 19th Century restorationPrior to their removal a 3D laser scan survey produced a sub millimetre high-resolution digital model of the gates. Once fully dismantled, individual components of the gates were also laser scanned at high resolution. Some elements beyond economic repair were re-created using 3D printing to form plastic replicas that were then sent to the foundry to create moulds allowing casting off new components. Some more complex components were replicated directly from the laser scan data by additive manufacturing and were printed in aluminium.
With Warrington Borough Council supporting a conservation-based approach, the project has not only recorded the Grade II* listed structure in great detail, but work has been undertaken that conserves and enhances the gates, ensuring them many more years as a much-loved symbol of Warrington’s civic pride.
Ramboll has provided the council with conservation advice, structural engineering design and contract administration of the works, liaising closely with specialist contractor Hall Conservation Limited, who brought their in-house metalwork expertise to the project.
Fay Newham, Associate at Ramboll, said: “Our aim was to deliver a high standard of repair and leave a full and detailed record for the next generation. The realisation of these objectives has been made possible with extensive conservation experience and 21st Century technology and techniques, which have enabled us to re-create intricate components accurately, and re-assemble with concealed fixings and strengthening. The Golden Gates were originally created by the Coalbrookdale Company to showcase their skills at the Great Exhibition in 1862, and today no-one could cast such large, complex pieces, so we have had to take great care with them. It is a special project not only to the Town of Warrington but also for us, as conservation engineers”.
The Ramboll led team included Thornton Firkin LLP, Russell Geomatics Ltd and Keystone Heritage.