The Arts Centre of Christchurch is a locally, nationally and internationally significant set of heritage buildings, which gained even more significance as the devastating earthquakes of 2011 destroyed so many other parts of the city’s built heritage. The repair, restoration, strengthening and conservation of these historic buildings was an extremely complex task from a structural point of view, with each separate structure presenting its own set of challenges and demands. To compound the technical difficulties of the site, variability of construction materials and the extent of the damage, the structural strengthening elements need to be ‘invisible’ as far as possible, in order to preserve the unique and precious heritage features.
Block C of the Neo-Gothic Christchurch Arts Centre comprises the Great Hall and Clock Tower, among other historical parts of this important collection of heritage buildings. Following the devastating earthquake in 2011 the badly damaged buildings were repaired, restored and upgraded to enable the centre to continue to play its role in the cultural life of the city, with an enhanced and robust structure.
The challenges which were presented to, and met by, the engineers included a difficult site, multiple materials, extensive damage, and the necessity of integrating structural reinforcement in an invisible manner, as far as possible. They required cataloguing of thousands of structural and non-structural elements, painstaking deconstruction of roof and wall elements to enable seismic resistant structural components to be inserted within the original volumes, before reinstating the original exposed features in their previous positions. Strengthening roofs, floors, walls and foundations, and binding them together to produce a seismic resistant structural whole in a manner that is all but invisible, is a significant and elegant feat of structural heritage renovation.