Crumbling skyscrapers a rare event: expert
Canadian Press
May 16, 2007 at 6:08 PM EDT
Toronto — Canada's tallest office building is more than 30 years old and just shed a large chunk of siding, but an architecture expert who found himself stuck in the traffic jam created by the mishap said Wednesday that there's no reason to worry.
As he slowly negotiated his car around the cordoned off First Canadian Place in an attempt to get to his office just blocks away, University of Toronto architecture professor David Bowick cautioned from his cell phone that such incidents are rare — given that building technology has improved drastically over the years.
“I don't think that there's any reason I wouldn't walk down the corner of King and Bay [streets] tomorrow,†Mr. Bowick said, referring to the intersection that's considered the heart of the country's financial community.
“I wouldn't worry that because this happened once that it's about to happen again.â€
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Chunk falls off downtown Toronto office tower
Roads still closed after marble piece breaks off First Canadian Place
The City of Toronto issued a work order against First Canadian Place after a slab of marble tumbled from the building's 54th floor onto the third floor mezzanine around 4:30 p.m. Tuesday.
The incident prompted officials to close down surrounding roads, causing traffic jams and lengthy commuter delays in the city's downtown core.
Engineers are looking into what happened and noted the inspection will likely last several more days, said Brookfield Properties spokeswoman Melissa Coley.
“We're working closely with everyone to remedy the situation and get the building fully operational and back in action as soon as possible,†she said, adding business inside the building was not affected. “The safety of the public is our No. 1 priority.â€
A tile replacement program was ongoing when the company bought the building 18 months ago and tiles are inspected every six months and replaced as required, she said.
The incident was reminiscent of a situation in March during which the CN Tower began shedding shards of ice following a storm. A major downtown highway was closed for 24 hours as a result.
While First Canadian Place, which was constructed in 1975, is considered to have a very modern outer “envelope,†Mr. Bowick said buildings that have undergone retrofitting could experience problems.
Older buildings, for instance, often weren't insulated, he said, noting that doing so years later could lead to things like frost buildup and deterioration of brick.
On the other hand, Mr. Bowick said some older design models are much more robust than today's buildings.
“These new building techniques are much better than the old ones in some respects, but there's always a loss with the gain,†he said.
“As we change systems, we introduce things to solve one problem and abandon a system, and in doing so, sometimes we create a new problem that we didn't anticipate.â€
In this case, Mr. Bowick speculated that a corroded anchor or a faulty stone could be to blame as corrosion is common on older anchors that aren't made of stainless steel, while natural materials like marble have inherent flaws.
yup! that's how they add floors to skyscrapers. by the time it's done, there should be another 10 floors. 
