Reviving Heritage: Restoring Christchurch’s Historic Gems

Dustin and the team at Oamaru Stone have recently had the pleasure of working closely with Scottish stone maestros Kris and Stuart, from Pinnacle Masonry in Christchurch. Restoration has been taking place on both the Trinity Congregational Church (now home to The Church Brew Pub), and the historic Provincial Chambers on Durham St North, both of which were significantly damaged in the 2011 earthquake.

While at first glance, the church appears to be entirely made of traditional grey Canterbury stone, the building contains a significant amount of limestone. The corner detailing, both inside and out, window frames, cornices, and door surrounds, were all in dire need of a makeover, and we were honoured to be asked to participate in such a significant restoration.

As much as possible of the original material has been retained during the renovations, but there was a significant amount of damaged masonry that needed to be removed, and then replicated as closely as possible to the original. Kris only used limestone from Oamaru Stone, as he firmly believes it is a more durable product than its North Island equivalent.

He also relied on the precision of our trusty 5-axis CNC machine, Zeda, to recreate the stunning circular gables. While they appear to be one piece of limestone, the new gables are comprised of several thin ‘puzzle pieces’, which fit together seamlessly to look indistinguishable from the originals. Only a robot was capable of cutting these pieces down to to a depth of 40 mm without cracking the stone, and the result is a stunning piece of architecture that is cheaper, and most importantly, much lighter in weight than the original.

Kris and Stuart cleverly used a combination of white concrete and limestone dust to disguise the lines between the joins, and the result is spectacular. While the new pieces of limestone look rather pristine next to their 150-year-old counterparts, in time they will age and mellow, and it will appear as if the renovation had never taken place, which is the ultimate goal for any heritage restoration.