But what is news is that glass technology is reaching new heights and architectural firms such as WZMH are keeping an eye on a recent innovation: vacuum insulating glass (VIG) manufactured by several companies globally.
Art Huard of Toronto-based GlassCan, a building envelope specialist in the glass and glazing industry, says VIG can provide close to four times the R-value that conventional glass offers.
He says VIG employs the same principles as insulated thermos bottles to prevent the conduction and convection of heat through the glass.
Typically, modern commercial glazing in Toronto consists of two lights of six-millimetre (mm) glass, an air gap of 12.5 mms, a Low e-coating and possibly filled with argon gas to achieve an R-value of about four, he says. By comparison, VIG employs only a thin vacuum space between the two glass lights to achieve an R-value of close to 15.