For those of you who couldn’t make it to the GANA Fall Conference, held September 23–25 in Toronto, following are some takeaways, with more to come in next week’s blog.
Vicente Montes-Amores of CDC made a presentation about solar radiation that was thought-provoking. He noted that we not only need to consider how much solar energy passes through glass, we should also be mindful of what becomes of the reflected energy. Vicente also mentioned that North Carolina’s rule outlawing low-E glass in residential applications has been overturned, for now.
The GANA Energy Division talked about developing a Glass Information Bulletin (GIB) on how to mitigate the effects of reflectivity, but many people expressed concern about unintentionally implying that reflectivity is a problem, thus opening up the GIB to being more of a reaction vs. action-type message. A video put out by the vinyl siding folks, regarding vinyl melting due to solar reflectivity, clearly laid the problem at the foot of the Low-E glass currently used in new home construction.
Exxon’s headquarters in Houston, built in the 1960s, may give a great clue for stopping reflected light off a building. If you don’t allow the sunlight to reach the glass, there’s no need to worry about reflectivity. The building’s architect designed sunshades that are approximately 6-foot-wide that protrude from the building at every floor. The sun only reaches the glass early or late in the day, when the energy isn’t as intense. The glass isn’t filmed or insulated—it’s just plain, old quarter-inch clear. But, Exxon hasn’t seen fit to upgrade it, as far as I know. Such indigenous architecture can be instructive on how people dealt with local climate challenges long before mechanical systems and glass wall systems came on line.
Other innovative designs might be out there, but if the courts ever determine that a new building owes an obligation to not increase the thermal load of their neighbor’s building, the architecture of buildings will have to respond. For example, if a building gets built with all the innovation on the energy front, but a new building that gets built next door causes changes in the original building’s energy performance, due to shading or reflectivity or 100s of other reasons, how is that going to settle out, and what impact will that have on future design and building?
The GANA Insulating Division is working on a hot-bent glass GIB in which the glass is heated and formed to a specific radius. Once that is developed and published, the group is going to turn its attention to cold-bent insulating glass. Also on track is a GIB for gas-filled IGUs. When asked about whether the gas-filled units lose any gas over the lifetime of the glass, the answer was non-committal: “There’s no empirical data on that at this time.” This is in a sense like testing fading on finishes, in which you put the glass through an aging process or leave it in the sun to see if the values drop over the years. Isn’t someone working on that for IGUs? To the best of my knowledge, there’s nothing out there that says it’s any less of a problem than it was when gas-filled units first came on line.
Also, a working group was formed to look at butt-glazing insulated glass without a supporting member behind it, much like the practice using monolithic glass and having just a sealant joint between. Point supported insulating glass can do this, so it shouldn’t be much of a reach to allow this in non-point supported applications.
Just about the time you think the world is a really big place, something happens that smacks down that theory, right quick. It’s pretty surprising what you find out when you talk about something other than glass at any of these types of conventions. Rick Wright has been heavily involved in GANA for much longer than I’ve been, but it wasn’t until I sat next to him last week that I found out he and I went to the same high school within a few years of each other. Rick, Ed McCoy said to say hi!
On a closing note: Vicente Montes is a real up-and-comer, I expect he’ll be making an impact on the glazing profession for quite some time.