The city is abuzz with reports of glass panels from condos exploding and raining down on the street below. The incidents have been centred around two developers Lanterra

  • One Bedford (Bedford and Bloor)
  •  Murano North (Grenville and Grosvenor)
  •  Murano South (Grenville and Grosvenor)


  • Festival Tower (King and John)

Why is this occurring?

Simply put:  defective glass

Doug Petovic, a University of Toronto engineering professor, explains that glass, with defects, are vulnerable to stress. As the stress builds up overtime, the defect spreads like a cancer, eventually causing the glass to explode into many small pieces. Figure 1 Professor Petovic put some of the glass under the microscope and found tiny cracks within the glass. Figure 2 Exploded glass pebbles that result from the  defective glass Normally these small pieces won’t pose a problem, but because of the height they come from,  the pieces can rain down on the streets with a velocity that is very dangerous.

So what’s being done?

Lanterra has taken the following steps to protect people around their problem condos.

  1. Place warning signs
  2. Putting up Scaffolding systems to protect people on the sidewalks
  3. Immediately removing the glass and railing systems in all affected buildings
  4. Replacing tempered glass with laminated glass. Laminated glass technology closely resembles car windshields and is much stronger than tempered

Does this mean there is a major problem? Well, tempered glass has been used for decades in the development industry in Toronto and the particular type tempered glass used by Lanterra meets or exceeds building code standards, so according to city staff, these are just isolated incidents.

Is it really so isolated?

A recent Tweet may dispel that notion. City Councillor Kristyn Wong-Tam has indicated that other incidents are going unreported.


Let’s see how this story develops.