As I mentioned last week, a lot of ground was covered during the GANA Fall Conference. This is Part 2 in a series whose final length I know not. If you’ll bear with me, I’ll try to wrap up the Laminated Division meeting this week. If time and space permits, I’ll get into the Energy Division.
To pick up where we left off in Part 1, the laminated folks are also concerned with the long-term exposure of the edge of the laminated glass lite in most typical handrail applications. Of special note: What effect does grout in exposed exterior handrail base shoes do to laminated glass? There’s no recently completed or in-process testing that indicates whether or not the grout and interlayer will play nice with each other. Anybody out there developing a “dry” system with extruded shoes will be ahead of the curve.
From a development standpoint, it appears there’s also interest in making laminated glass with lites that aren’t necessarily the same thickness. This raises a number of questions. What happens to glass strength if a ¼-inch and 3/8-inch lite are laminated together? Is it twice as strong, or 2.5 times as strong? When different thicknesses are laminated, is there an impact to energy or sound transmittance and the glass’ overall performance?
And, that’s just the starting point. Let’s go beyond different thicknesses of glass. What happens when you combine glass in laminations that aren’t all glass? For instance, what happens when you laminate glass to metal panels or composites? This naturally leads into a discussion about strength and ASTM E1300. How does laminated glass perform in combination with other products? With all the attention that putting fabric, patterns or pre-printed screens into laminated glass is getting, no one knows how to account for the overall strength of the laminated glass after it’s been fabricated with these “ingredients.”
In the Energy Division, Tom Culp reported that Climate Zone Borders are being fine-tuned to reflect more recent historical climatological data. The climate zones impact everything about energy performance for a building, not just the glass and glazing. While U-values are trending down between 8 and 14 percent, SHGCs are remaining steady (with some minor shifts) in upcoming code updates. Tom categorized these changes as “fair and reasonable.”
Learning to identify how products work in combination with each other to achieve the desired thermal performance is going to be a criteria of window and frame selection going forward. For example, when you pick a low-E glass, the zone the project is in may dictate whether or not the glass has to have argon in it, whether the frame has to be higher- or lower-performing, or whether a warm-edge spacer is required, etc., before finalizing a total product selection. Think of it in terms of a “cafeteria plan.” If you pick Option 1 for glass, then you have to do one or several other options, be it A, B, or C. But, if you pick Option 2 for glass and the location is in a different zone, then you may have to select from an entirely new set of options.
On a separate note, the NFRC’s recent changes haven’t cleared up where that program is going. They’ve made some fundamental software changes that allow faster responses from the CMA program, but their “reaching out to partner with the industry” claim hasn’t been clarified yet. There was some talk of AAMA and NFRC merging their certification efforts. That remains to be seen.
Also, if you’re not familiar with the LCA/PCR/ EPD/HPD acronyms, you might want to be. The analogy that they are “food labels” for building materials isn’t so much about what’s actually in the product, as it is about how much energy goes into using them in the building, and what their carbon footprint is over the course of the product’s life cycle. For example, they take into account the energy that goes into refining raw materials and getting raw material (stock lengths, for example in aluminum, or glass sheets prior to fabrication) delivered to fabricators, the energy it takes for manufacturers to make materials suitable for installation, the long-term operation or energy cost of the glazing or wall components after installation, and the cost to recycle them (if any). The terms, “cradle to gate” (from the raw material to the fabricator) and “cradle to grave,” (includes cradle to gate and through operation and recycling) are going to become more prominent.
Tracy Rogers of Quanex reported on a unique glazing approach for retrofit of an existing, monolithic glazed curtainwall that didn’t require any teardown or replacement of the existing window system, nor did it require a relocation of existing tenants. They employed a Quanex spacer applied to the cleaned interior surface of the existing glass, which remained in the existing frame. They then mounted an IGU on the back of that spacer into a Berkowitz designed interior glazing stop system applied inboard of the IGU, fastened to the existing window system. The completed installation resulted in a triple-glazed window, which obviously increased the energy and thermal performance of the glass. The net decrease resulted in 35 to 40 percent energy costs of what they had previously been, at 54 percent of the cost of what a tear out and replace budget might have been. While the frame performance wasn’t altered, some gain in thermal and energy performance was better than none. It was classic out-of-the-box thinking, which hopefully we’ll see more of as time goes on.
Enough for now … next week, I’ll recap the Flat Glass and Insulating Division. Between this week and last, we’ve only made it through about half of my notes. Please holler if you have any questions about any of the topics I recapped. There are certainly people in GANA a lot smarter than me on the details of these updates (and on any and all other matters) that you can be directed to for answers.
And, in the meantime, Blue Flu Pennant Fever has taken over Kansas City again, everyone’s going crazy and absolutely going gaga about the run the Royals are on again this year. All I can say about Game 6 last Friday night is (to use a phrase we haven’t heard of a lot of this year): “that what speed do.” Hey, Paul Bieber, challenge accepted! Go Royals, TAKE THE CROWN!!! (Full disclosure: You’re reading this on Thursday; this is being written before Game 1 on Tuesday.)