A group formed to save the Highgate Presbyterian Church in Maori Hill, which has been closed since 2016, has offered to pay for a full engineering assessment of the 100-year-old building, which they say has not been done.
The Presbyterian Church has argued shrinking congregations, of mainly older people, are no longer able to maintain the buildings, which face expensive work to earthquake-proof them.
Heritage developer Stephen Macknight said the group had seen a copy of the initial report the church had commissioned on the condition of the building and it did not include a full engineering assessment.
No calculations had been carried out and further assessments were recommended, Mr Macknight said.
As a result, late last month the group approached the church with an offer of a full engineering report at no cost to it, but so far it had not responded, he said.
An independent engineer had also looked at the report and determined it was not earthquake-prone and it was likely no strengthening work would be needed.
"So we told the church that and they still weren't interested ... It's very clear they're not trying to be open about this, and they're covering up to everybody what's really going on."
Based on information found in the report, Mr Macknight said he felt the church had misled the parishioners and the community.
The group is holding a public meeting on Wednesday in the Maori Hill Coronation Hall at 7pm.
Highgate Presbyterian Church minister the Rev Geoffrey Skilton said the church had received emails from the group outlining its proposal but he did not want make any further comments on the situation.
"At this stage, without consulting my other folk, I'm not prepared to comment, but we are continuing on with the process as we've agreed to do," he said.
Plans for the demolition were continuing and the church's organ was removed earlier this week, Mr Skilton said.
Once the church was demolished, an existing office building on the land would be kept in church ownership.
