Energy-efficient glass in the “battle for the wall”

The future of the Canadian glass industry isn’t opaque; it’s full of sustainable possibility
Wednesday, October 15, 2014
By Rebecca Melnyk

Since the introduction of legislation, like the Ontario Building Code’s SB-10 supplementary standard for large buildings and the B.C. Clean Energy Act, what once was considered energy-efficient glass—double glazing with low-e coatings, argon fill and thermally broken aluminum framing—is now the norm in real estate. But with Europe outperforming North America in terms of emerging technologies, and Canada not yet fully embracing newer trends, glass industry insiders see opportunity to advance energy efficiency.

“Areas like Vancouver, Ontario and Alberta are the leaders in Canada in terms of good energy productivity,” says Rich Porayko, marketing consultant for Vancouver’s Hartung Glass, freelance writer and glass consultant. “But compared to Europe, Canada is about 10 to 15 years behind on glazing trends.”

The not so distant future

According to Porayko, evolving technologies, like dynamic glazing, triple glazing and vacuum glazing, are the future of glazing and construction in North America; however, several obstacles prevent widespread use.

For instance, dynamic glazing incorporates building-integrated photovoltaics to optimize a window’s tint to selectively change transmission of light and heat and enhance performance. Yet, unlike parts of Europe, government grants are not offered to developers who wish to include such glazing in a building’s façade.

However, regulation is a proven force behind installation. “At the end of the day, it’s the building codes and legislation that’s the ultimate carrot making it happen,” says Porayko. “It’s very clear: the areas that have tight building legislation have significantly higher energy performance. It’s not driven by developers and owners trying to do the right thing; they have to hit these codes.”

Along with lack of incentives and a high cost differential comes the question of where responsibility lies throughout varying steps in the installation process, like wiring or maintenance.

As a result of such uncertainty, glazing contractors are now being urged to become leaders in developing and installing dynamic glazing, as few Canadian companies know how to install it.

Other trends like triple glazing, which can offer a solution to the growing demand for energy performance and sustainability, are seen in only about 10 per cent of buildings in Canada. Although they may be cost effective in the long-term, they remain expensive and can be used only with certain types of framing, strong enough to hold three layers.

Current trends worth embracing

Despite lower pace of adoption within Canada, there are available trends worth investing in, but they are not embraced by everyone in the commercial sector.

Michael Barclay, an engineer and manager of fenestration services at MMM Group Limited with vast experience in evaluating aspects of energy-efficient glass, suggests lack of awareness of these newer trends thwarts installation. Not only do people think the cost is higher, but they also prefer what they know.

“Particular technologies that offer further energy-efficiency gains can be implemented without much cost,” he says. “It’s a matter of educating professionals from architects to fenestration designers.”

For example, new warm edge spacer bars that reduce the amount of heat lost through a sealed unit are more sustainable than aluminum spacers, but people may mistrust the durability factor since warm edge spacer are made of foam or plastic and metal combination. “The norm over the last decade is to use aluminum because it’s strong and cheap and people have always used that,” says Barclay.

But Barclay adds there are many structurally sound projects with warm edge spacers and with the completion of more buildings, confidence in the products should increase.

Other available trends include high-performance framing: like aluminum with glass-reinforced fibreglass thermal breaks, which are more efficient; careful design to avoid thermal bridging; the use of passive solar gains; and the reduction in glazed areas.

Besides the low cost to implement some of these design strategies, occupant comfort and a reduction in interior condensation can be persuasive arguments. Warm edge spacers and high-efficiency glazing can reduce occupant discomfort that comes from being next to a cold window. Condensation, which usually forms around the edges of the glazing, can cause myriad problems such as rotting, corrosion and mold. Since the interior surface of high efficiency glazing is warmer, the tendency of condensation to form on the inside is significantly reduced.

Energy-efficent glass also adds value to a property. Porayko mentions that besides mandated building codes driving owners and developers to create sustainable properties, the perceived value of a building is another motivating factor. “If they have a property that is more energy-efficient than the property next to them, in theory they can charge more,” he says.

Whether the real estate industry embraces such trends as a whole, or encourages accessible use of developing technologies coming from other parts of the world, the glass industry recognizes the active role it must play in the future of sustainable building, that Porayko calls “the battle for the wall”.

“We have two options in the glass industry. Either we can stay status-quo and the size of the window will shrink and opaque building materials, like brick or wood will take over the façade of the building and what you’ll have is a trend towards a box,” he warns. “Or, to win the battle for the wall, we need to stay on top of energy performance and do what we can I order to reverse that trend.”

Rebecca Melnyk is online editor of Building Strategies & Sustainability and Canadian Property Management.


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