The ASHRAE proposal to reduce the window-to-wall ratio was dropped at the start of the year, but as a recent Urban Green Council report reminds us, the battle over glass performance is far from over. As part of the council’s efforts to establish better building envelope standards, the report calls into question the long-term benefits of expansive glass structures. Referred to as “high cholesterol buildings,” it explains how such buildings are on the fad diet of today, but have the potential to cause environmental problems in the future:
“We watch what we eat, exercise regularly, keep an eye on cholesterol, and make other common-sense lifestyle decisions now for better health in the future. But sometimes we take shortcuts, like fad diets that shed pounds in the short term while spiking our cholesterol and damaging our health in the long run. Buildings are no different…we seek shortcuts: ‘fad diets’ that make it seem at first glance that we’re building green, when in fact we are setting ourselves up to pollute more in the future.”
According to the report, one glaring, short-sighted fad diet in the building industry is using glass for the majority of the building envelope: “More glass translates into higher revenue today, but that same glass saddles buildings with poorer envelopes tomorrow.”
Undeniably, some glass still has a ways to go when it comes to energy efficiency. But, it also provides occupants with views to the outside world and access to sunlight. Since both are critical to occupant comfort and wellbeing, it is doubtful expansive glass building envelopes will be a passing fad.
Nicholas Holt, an architect at Skidmore, Owings & Merrill LLP, and an Urban Green board member, agrees. “Glass is not going anywhere,” says Holt in a Wall Street Journal article covering the Urban Green Council’s report. He adds that glass buildings will likely remain predominant for years because of the positive impact views and light have on human health and enjoyment.
As such, it is imperative the glass industry continues asking the right questions to ensure glass provides long-terms solutions that benefit both human health and the environment. How can glass become a better insulator, acoustic barrier or dynamic building element? What can we do to ensure framing materials improve thermal performance? What can we learn by partnering with architects to evaluate building envelope performance post-construction?
As the Urban Green Council report aptly points out, glass walls can last 50 years, and in some instances many more. By comparison, HVAC systems and other building equipment are typically upgraded and replaced every 10 to 20 years. This should underscore for all of us the importance of ensuring high-performance glazing contributes to energy-savings and promotes occupant comfort over a building envelope’s tenure.
The good news is there are many solutions we can pursue now. And, as the Urban Green Council sums up, “…with better glass, designed views, improved construction training, and greener codes, we can have buildings that are as healthy as they are beautiful.” Let’s do our part to make sure that glazing is part of the solution, and that future improvements are as healthy for building occupants as they are for the environment.
Jeff Razwick is the president of Technical Glass Products (TGP), a supplier of fire-rated glass and framing systems, and other specialty architectural glazing. He writes frequently about the design and specification of glazing for institutional and commercial buildings, and (past) chairs the Glass Association of North America’s (GANA) Fire-Rated Glazing Council (FRGC). Contact him at 800/426-0279.