The former manager of the Hotel Grand Chancellor says the building was checked for earthquake damage four times before the February earthquake caused it to slump, trapping dozens of people inside.
Steve Martin was speaking at the the Canterbury Earthquakes Royal Commission, which resumed this week and has focussed on how Christchurch's tallest building withstood the 6.3 quake on 22 February last year.
Mr Martin said the quake caused one of the hotel's main support walls to fail, which led to part of the stairwell in the 28-storey building to collapse.
He said about 30 guests and staff were stuck above the 15th floor before being rescued by a crane.
Mr Martin said engineers gave the building the go-ahead for use each time it was checked following the earthquake in September 2010.