The New Zealand earthquake royal commission has found a litany of failures associated with the CTV building, which collapsed in February last year killing 115 people.
The commission says there were deficiencies in the engineering design and in the construction and that the Christchurch City Council should not have issued a building permit for the structure in 1986.
It found the building was cleared for re-occupancy after the September 2010 earthquake, even though there was no engineer present for the inspection.
The commission didn't find a link between that inspection and the CTV building's collapse nearly six months later, however it did recommend improvements be made to the inspection process.
The final report also calls for changes in building practices and oversight.
New Zealand's Prime Minister John Key says the government will consider those recommendations and offer a response next year.
He says the report is a "grim and sobering" read.
185 people died in the Christchurch earthquake and Mr Key says he wanted to release the report as soon as possible for the victims' families.
The report is the result of an eight-week hearing, which heard evidence from more than 80 witnesses including building designers, engineers, inspectors, builders and survivors.