An engineering expert refused to give his opinion on whether Christchurch's CTV building was code compliant at today's royal commission hearing.

Professor John Mander, a Cantabrian who works in Texas A&M University's Department of Civil Engineering, was called by counsel for Alan Reay Consultants, the company that designed the CTV building.

The building, in the CBD, collapsed in last February's quake, killing 115 people.

When asked by counsel Stephen Mill for his view on whether the building's design was code compliant, Mr Mander said he would not give a personal opinion.


"Evidently the council thought that was fine at the time," he said.

Mr Mander confirmed he was aware of construction defects and issues of concern raised in the evidence of others at the hearings.

But he would not agree with the counsel's suggestion these defects showed the building was not, in fact, designed and built in accordance with the permit plans.

Mr Mander said that "for the most part they complied".

"Again I would surmise this was inspected by the city council and they would consider this to be satisfactory."

When pressed for his view, Mr Mander said the design "certainly wasn't best practice".

He said some designers took a "liberal interpretation of the code" as opposed to a more cautious, conservative approach.

Mr Mander suggested a slightly slower level two inspection, coupled with a look at the building's plans, would have been preferable to the level one inspection carried out after the September 2010 earthquake.


Had he reviewed the CTV building plans after the initial earthquake, Mr Mander said he would have been "loathe to go green".

He said design drawings lacked some of the "detailing that leads to robustness".

When asked how long it would take him to review the building drawings and complete an assessment, Mr Mander said: "It doesn't take long to look and see the details are not all that flash."

But he denied the counsel's suggestion he seemed to be calling the CTV design "obviously inadequate".

He said it was "believed to be designed to the demands of the day".

Mr Mander said that as the city council gave the CTV building a permit, the structure must have been designed and constructed in compliance with the applicable building codes.

But he went on to say he would not design the building as it was, and he would not teach his students to do it that way either.