This is the year the stabilisation of the Cathedral is achieved, and human entry will be safe enough to allow work to continue on more conventional terms
Main external support frames
Good progress has been made with the installation of the main external bracing frames on the west (both sides of the porch), north transept and south transept, and works are moving ahead well on the apse work to the east. In addition to substantial foundations, these frames have complex and substantial connections to ‘solid’ parts of the damaged cathedral. Once the critical support frames are in place, the remaining stabilisation work will involve installing a temporary roof over the crossing, removing the slates and roof timbers and deconstructing the heavy stone arches in the middle of the crossing to decouple the four major components of the cathedral, the nave, the north and south transepts and the apse. Once this work is complete it will mean all four components of the building will be independently supported by these external frames. This is a critical milestone for us as the building will no longer be earthquake prone and can be safely worked on just like any other site in New Zealand.
Installation of Triangular Frame
The deconstruction of the north transept gable is now complete. The new work will see the installation of a triangular frame in its place which will provide stability to the transept walls and support to the roof.
Deconstruction of Tower
The remnant of the tower stub is being manually deconstructed in areas where stone reuse is required. As with all the masonry deconstruction, the stone masons work methodically, in this case we plan to reuse the tower door and the surrounding stones and the large base sandstones on the new tower.
North and South Aisle walls
The aisle walls were badly damaged and require significant work to support the clerestory above, especially on the north side where the tower crashed through the roof. Permanent steel beams have been installed and will provide temporary and permanent bracing for these walls. Watch the installation video here.
The strengthening involves each section of the wall to be pinned and grouted, sections replaced, and some areas require new reinforced concrete walls to be installed within the wall thickness. These wall repair methods will be replicated around the cathedral to achieve the required level of strengthening. It will be time consuming but satisfying work. Essentially, we have to build these walls within the walls. We will commence this work as soon as feasible when the stabilisation phase is complete.