The stabilisation phase of the Christ Church Cathedral reinstatement is hitting a major milestone as the crossing roof removal begins.
Removing the crossing roof provides access to start the vertical deconstruction of the Cathedral’s stone gable arches in the crossing, an important element of the building’s structural stabilisation.
It’s a pivotal milestone in the reinstatement project that will decouple the Cathedral into four independently supported sections.
Project Director Keith Paterson says, “Once the gable arches have been removed, and other stabilisation work is complete, the Cathedral will be safe enough for personnel to enter – for the first time since the February 2011 earthquake. It also paves the way for wall strengthening work to commence.”
Innovation is playing a key role in this critical milestone.
“Because the building is too unstable to enter, we’ve come up with an innovative solution that will see workers enter the Cathedral through the roof once the tiles have been removed. This allows for the progressive, top-down deconstruction of the stone gable arches in the crossing. The arches will then be preserved until we’re ready to put them back into place,” says Keith Paterson.
To allow this work to proceed safely, a temporary steel frame has been lifted onto the roof and secured to new reinforced concrete connection platforms constructed at the clerestory/transept corners.
The steel frame houses a weatherproof, sliding scaffold roof which will protect the Cathedral’s heritage fabric while the roof tiles are off.