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Domtar RAAC roofing panels were known to be problematic 40 years ago: Source

Ian Harvey
Domtar RAAC roofing panels were known to be problematic 40 years ago: Source

A former Domtar employee claims it was widely known the company’s Reinforced Autoclaved Aerated Concrete (RAAC) ceiling panels used at the Ontario Science Centre (OSC) were suspect by the 1980s.

The verified but anonymous source was employed at Domtar in the 1980s and says by then the Siporex brand was already withdrawn from the market because it had problems and that OSC architect Raymond Moriyama was not happy with the issues which had developed with the panels used at the OSC built in 1969.

“I didn’t think much of it until years later when I was working with another project and met with Raymond Moriyama for dinner in Hazelton Lanes. When he found I’d worked for Domtar he was upset because of the problems with Siporex. This would have been around 1990 or so. It’s been 30 years but that’s my recollection. The (roofing) system failed and he agreed.”

He says Domtar started manufacturing Siporex because it was a natural fit with their drywall business at the time which used gypsum and incorporated it into the panels. Siporex was taken off the market and in 1978 Domtar sold off its construction materials business to focus on its core enterprise of paper.

Raymond Moriyama died last year and his firm, Moriyama Teshima, did not respond to a request for comment on this story.

The firm did state in an article with The Canadian Press the province’s decision to immediately close the OSC was “absurd.”

Brian Rudy, a partner with Moriyama Teshima Architects, said the roof panel problem should not have come as a surprise to the government.

“It needn’t have been because it has been known for years,” Rudy said. “This has been an issue identified decades ago.”

His firm analyzed the engineer’s report and he thinks there are a number of ways forward.

“Most of the panels actually aren’t even above exhibition spaces. So the urgency to close exhibition spaces is unfounded. In fact, all of the permanent exhibit spaces are free of this type of roof panel entirely, so it’s not even a concern.”

The firm wants the province to reverse its decision and has offered its services free of charge to help.

Former OSC CEO and chief scientist Maurice Bitran (2014-2019) also wrote about the roof being a long-standing issue in a Toronto Star op-ed Canada Day weekend: “…the roof leaked whenever it rained, there was no working capital to develop new exhibits or to bring new shows, and the auditors had even put a liquidity note in the financial statements.

“Not surprisingly, attendance was in decline. For decades, and under governments of all political stripes, this cherished Ontario gem had suffered from chronic underfunding and insufficient infrastructure maintenance.”

As Bitran noted, the OSC was chronically underfunded by successive governments and Infrastructure Ontario says outdated infrastructure and cosmetic repairs are now estimated at $478 million and rising, another factor in the government decision not to effect immediate repairs as demanded by political groups.

While two entrepreneurs have come forward offering up to $1.5 million towards repairs with the proviso the science centre stay where it is, the government has not responded.

Bitran says it’s time to abandon “nostalgia” and consider a small structure on the waterfront with a multi-function public space to generate revenues outside of the exhibits a good option. Most science centres around the world are smaller, he argues, and thus easier to fund and manage.

Some 366 Ontario schools have the same roof panels and need repairs, it has also been discovered. The consensus now, led by the Royal Institute of British Architects, is that the panels have a life span of only 30 years. More than 100 schools and buildings are similarly plagued in the U.K.

Adding to the lack of maintenance and noted in the engineering report commissioned by Infrastructure Ontario are several “field” installations which damaged the roof panels to install drains and other components post construction.


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