Evolution of Green

High-performance, environmentally sustainable construction market shifts its focus
Katy Devlin
July 18, 2018

Anaha Tower

Above: High-performance glass creates a wave-like façade that encloses the 38-story Anaha Tower in Honolulu. The building, designed by Solomon Cordwell Buenz in partnership with Benjamin Woo Architects, features 275,000 square feet of Guardian Glass SunGuard SNR 43 coating on CrystalGray glass, 20,000 square feet of which is bent glass. The podium features 50,000 square feet of Guardian SunGuard SuperNeutral 68 coating on low-iron glass. These makeups met the requested solar heat gain coefficient and visible light transmission requirements.

The project is designed to achieve a LEED silver rating from the U.S. Green Building Council's Leadership in Energy and Environmental Design program. The high-performance glass contributed to LEED certification in several categories, including the Energy and Atmosphere credit to optimize energy performance, increasing energy performance above the prerequisite standard, reducing the environmental impact of excessive energy use. Additionally, the building’s floor-to-ceiling windows allow for abundant natural light to come into interior spaces, which could contribute to the Indoor Environmental Quality credit for daylight for 75 percent of spaces.

Glass fabricators included Standard Bent Glass Co., Precision Glass Products Inc., Northwestern Industries and Glassfab Tempering Services. The glass was installed by Architectural Glass & Aluminum.

Photo by Marco Garcia.

“Green” doesn’t mean what it did 10 to 15 years ago. The green building movement, which previously was focused on energy, has expanded to include considerations of sustainability, recyclability, life cycle, wellness and more. Discussion of individual product performance has transitioned to consideration of full-system and full-building performance. 

This evolution has changed what “going green” means for glass companies and the entire glass industry. Companies face tougher codes and standards, demands for more detailed product performance data, increasingly complex project processes and more. 

This article explores the new world of green building, tracking trends to watch and what they mean for industry companies. It presents key terms and definitions and addresses common myths about glass and glazing performance. 

Life Cycle Definitions

Life Cycle Assessment: An LCA addresses the embodied energy/carbon footprint of a product, taking into account factors such as acidification, fossil fuel depletion and human toxicity.

Embodied energy: Embodied energy is the total energy consumption from a building material’s extraction, processing, manufacturing and delivery. 

Product Category Rule: The PCR scopes and sets rules for conducting the Life Cycle Assessment. The PCR ensures every company measures the impacts of a product in the same way.

Environmental Product Declaration: An EPD discloses the life cycle environmental performance of a product. (The labels are similar to the nutrition labels for the food industry.)

Source: Definitions derived from the presentation “Eco-labeling is Coming: Is the Glazing Industry Ready?” by Helen Sanders, strategic business development, Technoform Glass Insulation NA Inc.

Trend watch

1. Life cycle over energy efficiency. 

Ten years ago, the focus of green performance for glass and glazing was often measured in terms of thermal and energy efficiency. The movement has evolved, taking on a more holistic and long-term approach, with a focus on sustainability and life cycle. 

“Energy [efficiency] still matters, but how does it fit into the big picture of the sustainable building movement?” asks Max Perilstein, founder of Sole Source Consulting

“We became myopic about energy—the energy consumed during building operations. … Now we are starting to think in terms of life cycle,” adds Mic Patterson, director of strategic development for Schüco USA. “When we consider how we create a sustainable built environment, we need to be talking about fundamental issues like life cycle, durability. We’ve made progress, but there is a long way to go.” 

2. Demand for product transparency. 

The increased focus on life cycle corresponds with demand for product transparency, primarily environmental product declarations. EPDs disclose the life cycle environmental performance of a product. They are developed during a life cycle assessment process, in which the environmental impact of component parts is measured according to product category rules. (See definitions of life cycle terminology at right.) 

Some architects and owners are also seeking health product declarations, HPDs, which disclose the content and associated health information for building products and materials. An HPD offers information on product chemical content and potential health hazards.

“We’re not seeing heavy demand for EPD and HPD yet, but it is working its way through our world,” says Perilstein. 

There is concern among manufacturers and fabricators about requirements for transparency declarations, as the process can be expensive and complex. “Many companies don’t yet understand the process or the requirements,” Perilstein says. “But we are seeing some companies begin to get it.” 

Industry officials say they expect to see increased demands for product declarations, particularly EPDs, as more rating programs and building code requirements seek building product environmental disclosures. 

3. Tougher building and product requirements. 

Building energy codes continue to become more stringent. (Read the Codes & Standards article on page 20 for details of the 2019 version of ASHRAE 90.1.) Several jurisdictions, such as California and Seattle, have adopted their own regulations that up the performance requirements even further. In October 2017, for example, California Governor Jerry Brown signed into law the Buy Clean California Act, which sets maximum levels of embodied carbon emissions for building materials used in state infrastructure projects. “The new act means there is a life cycle assessment that has to be considered in state procurement,” Patterson says. 

According to BuyCleanCalifornia.org, “The State of California spends more than $10 billion annually on infrastructure projects, such as bridges, roads and state facilities. Beginning in 2019, Buy Clean will require contractors who bid on state infrastructure projects to disclose the greenhouse gas emissions data for certain materials they use in these facilities, such as steel and glass.”

4. Moving beyond LEED. 

A key driver in the green building movement has been the U.S. Green Building Council’s Leadership in Energy and Environmental Design program. While LEED continues to be a key player among green building rating programs, the field has widened, allowing architects to consider different metrics when evaluating the performance of their buildings. Key rating programs include the Well Building Standard, Living Building Challenge, Passive House and Green Globes. 

“LEED is no longer the only game in town,” says Perilstein. “[Architects] are interested in programs that factor in healthy buildings, and anything with net zero.”

5. Push for product performance.

Higher performance expectations mean glass companies increasingly will be asked to look beyond traditional glass and glazing systems. “The energy codes and standards require higher glass performance, and a 1-inch standard double pane insulating glass unit may not be sufficient. Fabricators and glaziers are asking how to improve glass thermal performance and satisfy the code requirements,” says Chia-Ling Yuan, Northeast regional technical advisor for Guardian Glass. 

Triple glazed IGUs, fourth surface low-emissivity coatings and framing systems with additional thermal breaks may be required to meet the next update to energy codes. (See the Codes & Standards article on page 20 for a more complete breakdown of product requirements.) 

6. Emergence of new materials. 

Tougher requirements could also lead to the emergence of different materials in glass and glazing systems. Timber curtain wall, for example, has become more common on commercial projects. “Wood is lower in embodied carbon,” Patterson says. “We are seeing mass timber. We’re seeing opportunities for wood curtain wall units.”

On the glass side, products such as vacuum insulating units could begin to penetrate the industry in a more meaningful way. “Using a vacuum between two panes of glass that prevents heat from escaping to the outside, [vacuum insulating glass] ... insulates like a wall,” says Yuan. “The product provides transformative thermal insulation with an R-value of up to 12 for 8-millimeter thickness, compared to single pane glass at R-1.” Guardian Glass recently debuted Guardian Vacuum IG to meet these high-performance demands. 

7. Eye on renovation and retrofit. 

Commercial and residential buildings constitute about 40 percent of all energy use in the United States. Improving energy performance in the existing building stock could go a long way in reducing overall building energy consumption, says Perilstein. “The biggest problem is our older buildings—buildings built in the late 80s and early 90s before anyone was putting in low-E,” he says. 

Renovation and retrofit, however, can be an expensive proposition. “The biggest problem is that these buildings fail to anticipate the need for future retrofit,” Patterson says. “We are left with very few options when it comes to renovating. The cheapest thing to do is strip off the entire façade and put up a new one. This is wasteful, expensive and very disruptive to ongoing building operations.” 

The building industry should begin to consider retrofit when designing projects and products. “We need to design for replacement,” says Tom Culp, owner of Birch Point Consulting.

8. Integrated project delivery. 

Achieving higher performance expectations requires a shift in project delivery. Early communication and collaboration are critical, particularly as project teams work to develop whole-building performance solutions. “What is central to the effort are collaborative delivery strategies—design assist, integrated project delivery,” Patterson says. 

Yuan agrees. “Guardian Glass recommends that architects and design teams adopt the integrated design process for designing high-performance buildings. IDP is a holistic approach that requires the whole project team to think of the entire building and all of its systems together, which means the team is working collaboratively to implement sustainability goals,” she says. “Applied during the early project stage, building performance analysis tools such as energy modeling, daylight modeling, thermal comfort modeling and heat transfer analysis are all critical to helping the team select the appropriate glass products.”   


Above: Wausau Window and Wall Systems supplied the window, entrance and unitized curtain wall systems for Portland, Oregon’s new LEED Gold Slate project. Wausau officials became involved early in the process to ensure the façade met the design team’s energy performance and aesthetic requirements. To meet project goals for energy efficiency and occupant comfort, Wausau’s aluminum-framed products have been thermally improved by Linetec, using a polyamide barrier. Combining the thermal barrier with solar-control, low-emissivity, insulating glass achieves the specified performance for low solar heat gain coefficient, low U-Factor, high condensation resistance factor and high visible light transmittance, according to Wausau officials. Seasonal opportunities for natural ventilation also help reduce the demand on HVAC systems and associated energy use. 

The project was designed by Works Progress Architecture. Yorke & Curtis Inc. served as general contractor and Dallas Glass as glazing contractor. The glass manufacturer was Vitro Architectural Glass. Firestone Building Products Co. supplied the metal panel inserts. 

Photos by Joshua Jay Elliott, courtesy of Works Progress Architecture and Wausau Window and Wall Systems.

Myths and misconceptions

Myth 1: Glass is the weak link. 

“Architects often consider glazing to be a major source of thermal gains and losses, which increases building energy consumption. However, with the right glazing products, building orientation, window-to-wall ratio and shading elements, the glass façade can effectively control environmental factors such as heat, light and sound,” says Guardian’s Yuan.

Myth 2: Glass performance trumps frame and system performance. 

The focus on glass performance often overshadows attention to frame and whole-system performance. “The glass industry did just about everything to improve the glass. Ultimately, the performance improvements became increasingly limited,” says Patterson. “There is a tendency to overlook what is going on in the façade. Contractors resist thermal breaks. Installation problems are overlooked.”

Myth 3: Center of glass performance numbers are all that is needed. 

The laser focus on glass extends to performance calculations. Many in the building industry rely on the center of glass U-factor measurements to calculate performance of a full system, sources say. However, the COG number relates only to the glass, not the system. “People are finally starting to realize that you can’t use the glass-only number to calculate the U-factor of the whole assembly,” says Culp. (Read the column on page 28 on the importance of edge of glass performance.)

Myth 4: When performance lags, the problem is the product.

When a glazing product or full façade doesn’t perform as expected on a project, “the finger of blame tends to strongly point at the glass,” says Patterson. The problem, however, can stem from any number of areas, from installation errors, to poor system design or integration, to lack of orientation considerations in design. Looking at the whole system and how it relates to the whole building can help a project team identify problem areas, ideally before a project is built. “I think the industry needs to take on the whole façade when it comes to educating the design and building community,” Patterson says. 

Next steps

For the glass and glazing industry to be successful in the green building future, innovation is critical, says Patterson. 

“The only way to create a sustainable built environment is through massive innovation,” he says. “We are a risk averse industry. But, we need to understand the limits of the industry, embrace the constraints, and focus on innovation. We need to experiment more, do more faster. … The more we can demonstrate that we can manage innovative processes and manage innovation materials, the more successful we’re going to be.”

Katy Devlin is editor for Glass Magazine. E-mail Katy at kdevlin@glass.org.