Volume 50, Issue 7 - July 2015

EDUCATION CONNECTION
CGA’s Annual Conference Offers Knowledge, Insight and Plans for Growth

by Ellen Rogers


C
odes, codes and more codes dominated discussions during the Canadian Glass Association’s (CGA) Glass Connections Conference, which also included the group’s annual general meeting, June 3-4 in Saskatoon, Saskatchewan. CGA said the annual meeting was the largest to date, and the association also almost doubled the size of its board of directors, from six to 10 members.

Glass, and What
Keeps it in Place


A variety of presentations focused on glazing issues gave attendees well-rounded programs covering some of the industry’s biggest topics.

Bill Coady with Guardian Industries gave a presentation titled “The Evolution of Glass and High Performance Coatings.” The session provided an overview of the basics of glass as well as the manufacturing process. He reviewed various fabrication processes, such as heat-strengthening and tempering, and covered some issues related to roller-wave distortion. While inherent in heat-treated glass, he said it is not a defect. There is not, however, an industry standard for acceptable roll wave distortion, only for bow/warp.

He discussed various low-E coatings and gave project examples in discussing current design trends and considerations.

“Don’t just spec ‘low-E,’” he advised his audience, which included a number of architects. “Be specific. There are dozens of configurations that can go on dozens of different substrates.”

As far as future trends and developments, he pointed out that dynamic glass is gaining interest, while vacuum glazing is still five to ten years away from widespread usage on commercial projects.

Nick Wutzke with Halfen Anchoring Systems provided a look at architectural anchoring systems. He began by explaining there are four basic types of glass and glazing systems: punched openings, ribbon windows, window wall and curtainwall.

Wutzke said there are several different ways of attaching these systems to the structure. For example, there are welded connections, drilled-in connections, and adjustable bolted connections.

Wutzke said a proper T-bolt connection requires coordination between the glazing subcontractor and general contractor. There are many sizes and capacities available for a wide range of applications, and these offer adjustability to accommodate construction tolerances and reduced field labor.

Providing a look at silicone vs. urethane sealants, Scott Waechter with Dow Corning Corp. spoke about the differences in the technologies, as well as proper building joint design and best practices for installation, among other points.

There are two broad categories of sealant chemistries available. Organic sealants consist of a carbon-based polymer. They are single- and multi-component polyurethane, polysulfide, acrylic and modified silicone. An inorganic sealant consists of a non-carbon-based polymer and is a silicone sealant.

Waechter explained that ultraviolet light has little or no effect on the silicone chemical bonds, but readily breaks down organic bonds.

Codes, Codes
and More Codes


Just as codes drive many discussions in the U.S. glazing industry, they are also important in Canada. John Hodder with Entuitive presented on cold-climate glazing and energy codes, and much of what he said was similar to some of the code considerations facing the glazing industry in the U.S.

“Energy codes are hard to keep up with,” Hodder said, noting that there are a lot of them, and many editions are frequently revised. “They are evolving quickly.”

Hodder said part three of Canada’s national building code pertains to the building envelope. There are three options in meeting the requirements: the prescriptive route; the tradeoff option and performance-based compliance. He says most projects opt for performance because of the leeway it provides.

The prescriptive path is based on overall thermal transmittance; the inverse of R-value. It is limited to the window-to-wall ratio and is stringent, he said. Ultimately, Hodder pointed out, it is based on the heating degree days the project falls within (with Canada split into eight climate zones). For example, based on heating degree days, Toronto can only have a 40 percent window-to-wall ratio. In other areas, such as Yellowknife, located in the Northwest Territory, they are limited to 20 percent.

Something Code, Something New

What can we do? That’s how Stanley Yee of Dow Corning opened his keynote discussion. He provided an overview of the various codes that relate to the glass industry, why it’s important to be aware of them and how they are evolving.

Yee began by saying that “knowledge of how the energy codes work can give you power to help your customers.” Specifications, he said, start with the codes, even LEED and the other green codes.

Speaking specifically of energy and green code trends, Yee said there’s been an overall increased code adoption and enforcement component. Even where it’s perceived to be lax, these codes will still be seen in specifications and product offerings

He also said the industry is seeing increased stringency in the base energy codes, as well as continued expansion of green codes and standards. “Be cognizant and have knowledge of these requirements,” said Yee. “Knowledge is power.”

Continuing to focus on stringency, he pointed to U-value requirements within ASHRAE 90.1 and said this has decreased since 2004. He said there is a three-year cycle to refresh the code, and each time it has dropped 5 to 10 percent every code cycle since 2004.

Yee explained that U-value requirements in colder regions of the U.S., for example, are comparable to those in Canada. In both cases, fenestration requirements are lagging a bit behind opaque walls.

Yee said that energy codes are going the same way, calling for double glazing, low-E and thermally broken frames almost everywhere, as well as triple glazing or two low-E coatings (second and fourth surfaces) in the far north.

Energy and green codes are calling for increased daylighting for windows, Yee said. The International Energy Conservation Code and ASHRAE 90.1 require toplighting for certain large spaces with high ceilings, etc. The codes are also calling for daylighting controls and plan submittals to show daylight zones.

Energy codes, however, were not the only types covered. Tim Nass with SAFTI First provided a look at “Code Considerations in Fire-Rated Glass.” He explained that the Ontario School Boards’ Insurance Exchange studied wired glass in schools and found that glazing is one of the most heavily litigated aspects of construction. He explained that building codes are evolving to restrict the use of wired glass in hazardous locations.

He told his audience there are two things to know before selecting a fire-rated glass product. First, glazing fire test standards fall into two basic categories: fire-protective standards or fire-resistive standards. Next, fire-rated glazing applications such as windows, doors and walls are rated to these fire test standards (fire protective and fire resistive).

Fire-protective products are always doors or windows; fire-resistive always refers to walls. “These stop the transfer of radiant heat,” he said, adding that resistive products are rated up to two hours.

Ready for More?

The CGA is currently making plans for its 2016 Glass Connections, which will take place in early June in Ottawa, Ontario.


the author

Ellen Rogers
is the editor of USGlass magazine. Follow her on Twitter @USGlass and like USGlass on Facebook to receive updates.


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