Christchurch real estate entrepreneur Stephen Collins said "trusted'' estate agents and lawyers carrying out due diligence on his behalf failed to inform him that engineers reports on the building revealed it had "the potential for severe failure'' in the event of a major quake.
He was giving evidence at the Royal Commission hearings into the Canterbury earthquakes today.
The 65-year-old owner of the building also spoke for the first time at discovering it had collapsed in the magnitude-6.3 earthquake in his home city while enjoying an Amazonian boat trip.
"I discovered what had happened to this building when I was 2500 miles up the Amazon in a boat and I turned on the TV and the first thing I saw was the lady being pulled out with a crane," an emotional Mr Collins told the hearing in Christchurch.
"It was one of the most horrific things that I have ever witnessed in my life, knowing that I owned the building and that there had been the loss of life of 18 people and many more hurt.''
Mr Collins bought the building from PGC in 2009 and transferred it into his company Cambridge 233 Limited, where he was sole director.
He told the hearing the purchase was conditional on due diligence, and part of that process was for building and LIM reports to be done.
Stephen Mills QC, counsel assisting the commission, highlighted a 2007 report by Holmes Consulting Group which described the PGC building as having an "unusual structural form''.
The report stated: "The columns step across at the first floor level to create a structural set-back that is part of the existing architecture. This is a severe weakness seismically as this discontinuity has the potential for severe failure.''
Mr Collins said he was unaware of the report.
He also denied being aware of a report by PBSL (Plant & Building Safety Ltd) which concluded the building was "potentially earthquake prone''.
The LIM report described the building as "earthquake prone'' and advised potential buyers to "engage a structural engineer to assess the building to determine the significance of this information.''
But Collins said he went ahead with the sale without ever knowing these crucial details.
He said: "This issue was not brought to my attention and there were no discussions of it with me at the time.
"They were brought to my attention after the earthquake of February 22.
"When this building was purchased, considerable time and efforts went into it by both Harcourts [his acting estate agent] and the lawyers.
"They reported back to me after the completion of the due diligence that they were satisfied that all aspects of due diligence had been completed and that I was in a position to confirm [the purchase].
"As in all cases of buildings that I have bought and sold, I have acted on the recommendations of professional people who have been employed specifically to look at the details and to identify problems in those details which may be an issue.''
Cross-examining, Marcus Elliott QC asked Mr Collins if he accepted it would be "quite expensive'' for a building such as the PGC to be upgraded and strengthened.
He replied: "At the time I purchased the building, there was no such thing as consideration of future earthquakes. If it needed to be done, and I'd discovered that it was a serious issue, it would have been dealt with.''
Me Elliott asked if since he was engaging to buy a 1960s-built property, he should have "initiated some inquiries about the capacity for that building to withstand an earthquake''.
Mr Collins replied: "Until the first earthquake we had in September last year, this was not an issue.''
Questioned over the potential high costs of due diligence and commissioning different structural engineers reports, he became agitated.
He said: "I can assure you, sir, the safety of the people in my buildings never relates to the amount needed to get a job done.
"Whatever that would've needed done, would've been done.''
The Royal Commission also heard evidence today that workers and tenants in PGC building after the September quake were "repeatedly told'' that their office tower in Christchurch was "safe to occupy'' before the fatal February quake that resulted in its collapse.
The people had raised fears over the 40-year-old PGC building's safety after finding cracks in its columns and a main load-bearing wall after September 4.
But five separate engineers reports over several months all concluded that the building was safe to inhabit.
The hearings into the Canterbury earthquakes, which killed 182 people, are being held in Christchurch and are expected to run into next week.
