The Anglican Church should release all advice and documentation regarding the decision to demolish Christ Church Cathedral, the Canterbury Earthquake Recovery Minister Gerry Brownlee says.

His call comes after the minister announced the Canterbury Earthquake Recovery Authority will release all documents in regard to the cathedral tomorrow.

More than 1000 CERA-held pages of information on the church will be made available from 9am tomorrow. CERA said the process will take some hours to complete due to the volume of material.

Mr Brownlee said the church should follow suit, given the huge public interest in the issue of the cathedral's partial deconstruction.

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"There are a range of views on the very difficult decision the Anglican Church has made about the future of its cathedral, and given the significance of the building this issue is of huge concern to many people in the community,'' Mr Brownlee said.

"I believe that if the public is able to see the advice the Church has been working from there is likely to be more understanding about the extent of the damage to the cathedral, and the rationale behind the decision to partially deconstruct it.

"At this stage a demolition permit has been issued to deal with the dangerously unstable tower and further permits will be issued to partially deconstruct the building as carefully as possible to no lower than two metres,'' Mr Brownlee said.

Fiona Summerfield, spokeswoman for the Anglican Diocese of Christchurch, said the church would review the Cera documents and if it believed there were other "relevant, appropriate documents'', it would consider releasing them.

"Throughout the process we have built relationships on trust and thus we would need to honour that in respect to documents provided,'' Ms Summerfield said.

She said the Cera documents would show the public the church was involved in stabilising and making the cathedral safe before December 23 but the two large aftershocks that day meant those plans no longer met Cera safety requirements and a new decision had to be made.

"Throughout the work on the Christ Church Cathedral we are continuing to carry out assessments and this is providing more detailed information on the state of the building,'' Ms Summerfield said.

"We have already had to change the approach to taking down the tower because it was more dangerous than initially realised.''

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The Canterbury Diocese of the Anglican Church, who announced in March the iconic church would be brought down to 2-3 metres, has previously rejected calls by opponents of the demolition to release the engineering report behind the decision.

Spokesman for the Restore Christchurch Cathedral Group Mark Belton welcomed CERA's decision to release their information.

"That's the beginning of a more open process that should have been going on all the time,'' Mr Belton said.

He also welcomed Mr Brownlee's call for the church to also make their information public.

"With that information there would certainly be better understanding, but I can tell you now the church's own engineering consultants Holmes [Consulting Group] provided three options, and the option the church has opted to follow is the one with the least conservation and the most demolition.''

Mr Belton said the suggestion the cost of the rebuild - estimated to be between $30m and $100m - was prohibitive was "absolutely ridiculous''.

"That's just a such smoke screen for something else. The church has also got to open up about what its deep agendas are. It is known the church has a major financial shortfall because of inadequate insurance cover.

"What one doesn't understand is why the church hasn't engaged with the local, New Zealand and international community who want to see the Cathedral restored and would contribute generously to that end.''

Mr Belton said the funds for the rebuild could be found "very readily'' from a combination of church, Christchurch City Council, Government and donated money.

More than 1000 CERA-held pages of information on the church will be made available on the CERA website, from 9am tomorrow morning.

This process will take some hours to complete due to the volume of material.