Parker's glass-cover plan may be one of cheapest

Encasing the ruins of the earthquake-damaged Christ Church Cathedral in glass may be an ambitious idea, but it could be one of the cheapest options pitched to the Anglicans yet.

Mayor Bob Parker's controversial proposal to build a crystalline structure over the remnants of the cathedral was unveiled last week and he has now revealed the project could cost $45 million.

Previous rebuild options commissioned by the Anglican Diocese of Christchurch have had cost estimates of about $80m. Restoration costs have been estimated at about $100m.

Parker has suggested retaining as much of the cathedral walls as possible, removing the damaged roof to expose the rafters and beams, and building a glass case over the ruins to protect it from the elements.

More than 2200 people voted on a poll on Parker's cathedral idea, with about 70 per cent in favour.

The mayor had not originally put a price on his plan, but, after his proposal received such a positive response, spoke to several experts to get a "ballpark figure".

"The feeling from a few people I have spoken to in the area of commissioning and working with capital programmes is that it would cost between $30 and $45m," he said. "But it all depends on how detailed it is, how high, how wide, how complex."

The price included deconstructing parts of the cathedral and the lighting, electricity and air conditioning for the glass structure.

Parker found his inspiration for the idea in Norway's Hedmark Museum, which has a large glass encasement protecting the ruins of Hamar Cathedral. The glass structure was built in 1999 and cost US$12.4m (NZ$14.8m).

The Christchurch City Council glass-enclosed visitors' centre that is being built in the Botanic Gardens was priced at $16m and the glass facade wall of the Christ church Art Gallery was insured for $5m in 2001.

Four cathedral rebuild options, commissioned by the diocese and designed by Warren and Mahoney, were estimated at between $73.5m and $84.3m, excluding GST.

Restoring the cathedral was estimated to cost between $95m and $109.2, excluding GST.

Fairfax Media