July 20, 2006

Legal Issues

Shattered glass: one library’s challenge

Court case could have major impact on construction industry

IRWIN RAPOPORT

correspondent

MONTREAL

The administration of the Bibliotheque et Archives nationals du Quebec (BAnQ) hopes it can resolve a dispute with Pomerleau Inc., the general contractor who built the 33,000-square-metre Grande Bibliotheque (library) in downtown Montreal, before it hits the courts.

A court case could have legal implications that would affect the entire construction industry nationwide when it comes to issuing warnings and concerns regarding construction methods and materials, what constitutes an official warning and the responsibility for all parties to retain documentation.

The $90.6 million construction project, which began in 2001, was officially opened on April 23, 2005.

The postmodern five-storey building is clad with 6,200 U-shaped plates of glass of a type never used before in North America, placed horizontally on the copper uprights that run the entire height of the building.

The structure, designed by Patkau Architects (British Columbia) and Croft-Pelletier/Gille Guite from Quebec City, occupies a complete city block bounded by Berri, de Maisonneuve, Savoie and Ontario.

BAnQ/Bernard Fougères

The library’s experts contend that one-third of the 6,200 glass panels need to be soaked again.

In June, 2005, three of the glass plates shattered. In the first three weeks of July 2005, another three plates shattered.

Last May and July, an additional two panels shattered.

The library is cordoned off by metal barricades to prevent people from approaching the glass walls. All four street level entrances have covered walkways.

Following the first incident, the library hired Jean-Paul Bailon of the Ecole Polytechnique de Montreal and Patenaude Trempe to determine what was causing the glass to shatter.

Their investigations found that three conditions were required for the glass to shatter and that these conditions were found at the library.

Those conditions are:

• Significant scratches on the glass.

• That glass, which should be considered as living material, will expand when the temperature is hot and retract when the temperature is cold. It was found the glass panels were attached too tightly, which could cause them to shatter.

• That because the panels were attached tightly, there has to be a greater variation between the temperature at which the glass attached and the temperature outside for the panels to shatter.

“The tests also found that the soaking of the glass was problematic,” said Patrice Juneau, BANQ’s director of communications. “It did not correspond to Canadian norms in the field. This glass is supposed to break into thousands of very small pieces which look like pebbles.

About one-third of the glass panels tested (about 40) did not shatter into small enough pieces. This is what happened to the eight panels that shattered.”

The library’s experts also contend that one-third of the 6,200 panels need to be soaked again.

“While we were looking for that,” said Juneau, “we found that another one-third of the panels, when they shattered into pieces that were too big. Our experts are saying it is impossible for us to tell which of the panels have that defect and they recommend it would be much simpler to re-soak every single panel of glass, which would alleviate the problem.”

Pomerleau had also hired an expert whose report concluded the shatterings are to be expected with the type of decorative glass that clads the library.

“The possibility of glass breaking was known.”

Pierre Pomerleau, CEO

Juneau was told that based on buildings which have used this glass, a certain percentage of windows spontaneously shatter due to the nature of the material and that over time, fewer panels shatter and eventually, the problem would resolve itself.

The library’s experts and Pomerleau’s expert have met to discuss the problem.

“We are sticking with our experts’ opinions, which are based on very serious tests done in the laboratory over the course of a nearly year,” said Juneau, “which is not the case with the contractor’s experts, which is more of a theoretical approach.”

Asked if the contractor warned the library about the nature of the glass, Juneau replied: “No. The contractor has said this was something he has warned us about at one point, but we have no such record of these warnings.”

On July 6, Pomerleau, released a report prepared by Dr. Thomas Read, PhD., of Read Consulting, which rejected all the points brought forward by the library’s experts.

Read’s report stated there was no indication the glass panels fell because of scratches and cracks on the glass, by mishandling or improper placement and that standard plating does not apply to the decorative glass used for the structure.

Read also stated the possibility of spontaneously shattering glass panels for the type of glass used is well documented by the industry and imperfections in the glass during the manufacturing process were known by the contractors and library officials.

A special thermal treatment — a heat soak test (HST), if applied, said Read, would have substantially reduced the probability of spontaneous shattering.

This treatment was removed from the construction tender by the library architects, and was not included in Pomerleau’s contract and that of the sub-contractors.

The company expressed serious doubts regarding the removal of the treatment and warned that panels could not be guaranteed if the HST treatment was not applied.

Read stressed there were fewer broken panels at the library compared to situations at other projects, based on industry experience, which clearly indicates the sub-contractor, Vertech, hired by Pomerleau, did a proper analysis of the limitations of the glass and delivered the best product possible.

According to Read, the HST treatment, if applied now, would be pointless and would not solve the problem with the existing glass panels.

Read believes the security issue stems directly from the distance the glass fell. He believes the problem could be resolved by installing safety (laminated) glass as used in automobile windshields or by installing permanent protective infrastructure.

“The library was born of an international competition and its architectural concept is daring and avant-garde,” said Pierre Pomerleau, Pomerleau’s CEO.

“The work was completed according to exacting instructions and under the supervision of professionals and the people in charge of the project for the library.

“The possibility of glass panels breaking was known, but the impact on public safety was under-estimated by the project designers. Our relations with the library are excellent and we have every intention of collaborating with the designers to correct the problem.”

Meantime, the library hopes to avoid bringing the matter to court.

“We hope to find a solution as soon as possible,” said Patrice Juneau, BANQ’s director of communications.

“We don’t have any indication right now that this could take a judicial avenue. We don’t think it is going in that direction.

“Our discussions with the contractor are still very cordial, very positive and we’re still confident we’ll find a solution.”

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