One in an occasional series on the GTA’s growing density and its effects on life in the city.

Toronto needs its glass consciousness raised.

Building experts say resiliency and energy efficiency are going out the window with all those floor-to-ceiling glass walls being installed in the city’s towering condos.

“There’s only one reason why all these buildings have floor-to-ceiling windows: it’s because architects and builders are lazy,” maintains retired architect and developer Lloyd Alter, who now writes for and teaches sustainable design at Ryerson University.





    Pedestrians and cars navigate the busy intersection at King and Yonge Sts.

    Even Toronto’s new chief planner, Jennifer Keesmaat, allows there’s a problem with the windows’ efficiency.

    “I share those concerns,” she says. “We need to be talking about this more as a city: how do we ensure that we do build buildings that have resiliency over the long term?”

    It’s understandable, almost desirable, that developers want to move as quickly as possible. Keeping city roads blocked requires permits and frustrates the public. Logistics are a headache, especially for some of the newer guys on the building block who lack experience. And “window walls,” the system most developers are using, are not as pricey, durable or difficult to put up as “curtain walls,” which is how Toronto’s commercial towers were built.

    Time is money.

    But how fast is too fast?

    For Alter, the main problem is energy efficiency. The glass has almost no insulation capacity.



      “When you look at the size of the little window that opens — because the building code says you have to have a little window in there — it’s a little slot that’s the size of an ice-cream stand pass-through,” he bristles. “There’s no cross-ventilation. So they’re constantly fighting to generate air conditioning, to generate heat, all because they’ve built these incredible dense buildings and they’ve given them these terrible, terrible skins.”

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      However, Arash Beheshti, vice-president of construction for Concord Adex, which is behind CityPlace, says it has to be a marketable product.

      “People want glass because they want to look outside,” he says, adding there are many “misconceptions” about floor-to-ceiling windows in condos.

      “Brick doesn’t necessarily have a higher insulating value than glass,” he says, pointing out that usually only one side of a condo is exposed to the outside while the floor, ceiling and sides are not.

      “When you look at the heat loss per unit of a condominium, you’re looking at way less than at a house.”

      For Kesik, it’s also an insurance issue.


      Beheshti rejects charges that glass walls are more vulnerable to weather: “The exterior building envelope is actually more watertight, weathertight, when you actually don’t have multiple segments of different products. If it’s all glass, it’s actually more sustainable to the exterior weather than if you have brick-block-glass-concrete-wood.”

      When it comes to claims that glass towers use less energy, Alter is totally dismissive.

      “When you take the entire population of that glass building, and divide it by the entire consumption of that building, they will say this is green; we’re using less energy per capita,” he says. “It’s a fallacy.

      “If you look at the building as a whole rather than per capita, it’s using a huge amount of energy that wouldn’t have to be used heating and cooling because of all that glass.”




