When Glass Houses Become Hothouses

A group focused on smart architecture is warning that the many glass towers that have been built in New York City in recent years are at risk of becoming heat traps in a summer blackout.

The Urban Green Council ran computer models for six common varieties of homes in New York City, to see what conditions might be like in an extended power cut — something many neighborhoods experienced after Sandy.

Apartments with those alluring floor-to-ceiling windows did not do well.

By day five of a summer blackout, the temperature indoors could approach 100 degrees, according to Russell Unger, the executive director of the Council.

"It's like being in a car," said Unger. "You know what happens when you turn off the air conditioning off in a car — it heats up really quickly. Well, that's happening inside a glass building as well."

By contrast, a less glamorous low-rise brick building would hit peaks in the mid 80s on day five of a blackout.

But it's not all bad news for glass towers in the sky. The study said they would retain heat reasonably well in a cold-weather blackout.

This article has been updated to correct a typographical error.