The equivalent of 1 New York City will be added to the planet every 34 days for the next 40 years – Architecture 2030
We aren’t moving fast enough to slow climate change. The United Nations (U.N.) Intergovernmental Panel on Climate Change’s (IPCC) sixth assessment report stated, “Global warming of 1.5o C and 2o C will be exceeded during the 21st century unless deep reductions in carbon dioxide (CO2) and other greenhouse gas emissions occur in the coming decades” .
Cover image: Figure 1 According to Architecture 2030, U.N. Environment’s construction growth projections imply that the equivalent of one New York City will be built every 34 days for the next 40 years. Credit: Benjamin Gremler on Unsplash
Tipping points are being reached across the globe – in the Amazon, in the Arctic, in the coral reefs and beyond . Even lockdowns in 2020 around the world weren’t enough to get us on the needed emissions trajectory. The Arctic has already warmed 3.5o C, driving strange weather patterns in the Northern Hemisphere by allowing the polar vortex to “meander” south. Witness the severe cold in Texas in 2021. The Greenland ice sheet appears now to be on an irreversible course, caught in a positive feedback loop of accelerating melting, causing sea levels to continue to rise and disruptions of the Gulf Stream. Add-on effects of Gulf Stream changes will drive more severe weather in the Amazon, Europe and eastern North America, and will not bode well for marine wildlife survival.
Vast areas of the globe are projected to be uninhabitable by mid-century [3, 4]. Most of Vietnam, Bangladesh, and the major cities of Calcutta, Mumbai, Jakarta and Shanghai will be underwater, leading to hundreds of millions of climate refugees and major loss of global rice production. Top climate scientists are also predicting societal decline from a deterioration in quality of life because of repeated and ongoing disasters and crises, and widening inequality .
Construction is accelerating
According to U.N. Environment’s Global Status Report 2017 , buildings and construction account for 39% of the carbon emissions worldwide, split approximately 70%:30% between building operations (operational carbon), and building materials and construction (embodied carbon). And yet, we are in a construction boom. The report predicted 230 billion square metres of buildings will be added worldwide by 2060, doubling the current building stock (Figure 1).
We have the technology, we just aren’t using it
Not only are we building rapidly, but most of these buildings are being constructed without the highest performing envelope products and best-practice installation and commissioning processes that currently are available to us. And these buildings will stay in place for many decades, operating with suboptimal performance, driving emissions yet higher.
The IPCC report (chapter 9 – Buildings)  stated, “This energy use and related emissions may double or potentially triple by mid-century due to several key trends.” It went on to say, however, “In contrast to doubling or tripling, final energy use may stay constant or even decline by mid-century, as compared with today’s levels, if today’s cost-effective best practices and technologies are broadly diffused. The technology solutions to realize this potential exist and are well demonstrated.”
The report also identified the potential for a two- to ten-fold reduction in energy use for new buildings and a two- to four-fold reduction for existing buildings if “existing technologies, design best-practices, know-how and behavioural changes” are brought to bear. It specifically mentioned the need for high-performance building envelopes and daylighting, and identified the Passive House Standard, net-zero or nearly net-zero buildings, and the Integrated Design Process as energy efficiency strategies.
A high-performance building envelope is also critical to managing the impacts of severe weather caused by climate change. When the power goes out for days after a storm, a great building envelope can ensure occupant survivability. An efficient HVAC system will be useless. Baby It’s Cold Inside, the Atelier Ten study for the Urban Green Council,  demonstrated how quickly indoor environments in New York City can turn deadly in buildings even with code-compliant envelopes. Higher thermal performance envelopes would have helped Texans during the 2020-21 winter and Pacific Northwest residents during the 2021 summer heat wave. In total, 210 Texans died during the February 2021 storm and prolonged power outages, most due to hypothermia. The New York Times reported 610 excess deaths (compared to normal) in Washington and Oregon during that period , and British Columbia reported 569 heat-related deaths .
“Thermal Autonomy” and “Passive Survivability” are key building performance metrics, yet are not widely used in building design.
According to Ted Kesik, University of Toronto, Passive Survivability is “a measure of how long inhabitants may remain in their dwellings during extreme weather events that knock out their energy supply” .
Brendan Levitt, and the team at Loisis + Ubbelohde Associates, defined Thermal Autonomy as “the percentage of occupied time over a year where a thermal zone meets or exceeds a given set of thermal comfort acceptability criteria through passive means only” .
If adopted along with operational and embodied carbon emissions, these metrics would drive an envelope-first approach to design, improving both operational performance and resilience of our built environment and supporting the use of available high-performance technologies.
Barriers to adoption
In the Spring 2021 edition of IGS, in asking the question “Do We Need More Innovation?” we touched on the barriers to adoption of high-performance envelope technology adoption . Building code stringency (or lack thereof) was identified as a primary barrier, along with simplistic cost-effectiveness calculations that don’t include the real cost of carbon emissions, and the lowest cost bidder design-bid-build process (Figure 2).
At Technoform, we have done further research into energy codes and their correlations to the business-as-usual fenestration thermal performance in key geographic regions across the globe. This study has been laid out in a three-part blog published by IGS in June 2021 , and in a follow-up blog in August 2021  focusing on hot climates. The key findings are summarized below and illustrated in Figures 3-5.
Code stringency is king
The data illustrates clearly that widespread adoption of existing thermal zone technology for fenestration is driven primarily by a jurisdiction’s appetite for building energy efficiency – not by the availability of technologies. Northern Europe (Germany and Scandinavia) have driven the thermal barrier and warm-edge technology development. Figure 6 shows the development of thermal barrier technology since 1970 and the adoption by countries across the globe compared to Northern Europe.
Fenestration backstops work
How prescriptive the code language is for minimum expected fenestration assembly and component level performance, also drives typical business-as-usual performance. Those energy codes that also specify maximum allowable U-factor and/or minimum thermal barrier dimensions (such as in Germany and China), even when following performance compliance paths, result in higher performance fenestration to be adopted as business-as-usual. This typically includes wider, more complex, thermal barriers in frames and warm-edge spacer.
These “fenestration backstops” have shown to be effective at preventing designers from trading higher efficiency mechanical and lighting systems for poorer envelope components to reach the target energy performance. This trade-off happens often in the U.S., leading to lower installed fenestration performance than if the prescriptive compliance path was followed. However, some U.S. jurisdictions have implemented full envelope backstops in which the total envelope U-factor must meet a defined target to address this issue. The downside of this approach compared to a fenestration backstop is a potential trade-off of transparent area for opaque elements, which are better insulating.
Climate zone isn’t always the determinant
Climate type plays a role – colder climates will generally have lower U-factors prescribed than hotter climate zones to achieve a similar level of stringency. While this is typically the case within the same country, region or jurisdiction, it isn’t always the case between countries, regions or jurisdictions. For example, the United Arab Emirates, located in a desert climate zone, requires more stringent U-factors (1.9-2.1 W/m2 K using either NFRC 100 or ISO 10077) than much of the U.S.
When typical fenestration in similar climates across regions is compared, the code stringency and the way it is implemented, appear to be the most important factors driving installed window performance (Figure 7).
Compare, for example, Germany and Scandinavia to the central and northern United States (Figures 3a and 4a). While U-factors cited by North American and European codes are not precisely comparable because of different calculation methods (NFRC 100 versus ISO 10077), the U-factor values for the same window are typically not more than 30% different from each other. Comparisons can be made using the U-factor maps and associated code-compliant fenestration systems in Figures 3-5.
Notice too, that the typical window systems that meet the codes are markedly different from each other. A commercial window system needed to meet the prescriptive code requirement in Chicago (U=2.2 W/m2 K, NFRC 100) would typically use an argon gas-filled, dual-pane, low-e insulating glass unit with an aluminium spacer and a thermal barrier width of less than 15mm (Figure 4b). In comparison, business-as-usual in Germany (with a requirement of 1.3 W/m2 K, ISO 10077) is a triplepane, low-e, argon gas-filled insulating glass unit with a warm-edge spacer and a frame with complex thermal barriers wider than 40mm (see Figure 3b).
It is clear that building regulations are the main driver of installed fenestration thermal performance. In the words of Duane Jonlin, a code official in Seattle, Washington, who is driving code stringency in the U.S.: “The only places you’ll find high-performance buildings being consistently constructed at massive scale are those places where it is the only way to get a building permit…”
We need an intervention
Economists have already concluded that climate change is the result of a market failure. The negative economic consequences of emitting greenhouse gases do not accrue immediately to the emitter. They are typically borne by others elsewhere on the planet or will be borne by future generations. Therefore, emitters continue to emit, seeing no need to adopt energy-efficient building technologies.
Economists are actively promoting government policy interventions to create immediate disincentives for emitting. They are currently optimizing a complex stochastic model to refine estimates of the future economic cost of emitting a tonne of carbon today, in today’s currency. This is called the “social cost of carbon” or SCC. The discount rate used – how much this generation should discount the well- being of future generations – is under debate and has a significant impact on the SCC. The SCC can be used to effectively price carbon emissions and to create public policies, which will drive the adoption of high-performance building products and processes to needed lower emissions, while minimizing the impact on social equity.
We can’t rely on the building industry (nor any other) to do the right thing on their own. The building industry needs “carrot and stick” interventions globally: Incentive structures (carrots), such as tax credits, to drive the adoption of higher performance technologies and new innovations, creating economies of scale and driving down cost. More stringent codes (sticks) to raise the performance of the lowest legally allowable building, and which are carefully crafted with multiple appropriate targets to drive to a net-zero carbon goal, while ensuring against unintended consequences. For example, energy use intensity targets should ideally be replaced by one for carbon emissions. That is what we must reduce after all, and energy use doesn’t always correlate with carbon emissions. As the saying goes – you can’t manage what you don’t measure.
Also, is one metric sufficient? The use of multiple targets – for both operational and embodied carbon, for passive survivability, for occupant health, and for façade maintainability and service life would guard against negative consequences of a single metric-focused regulation. It is too easy to trade service life, which is often difficult to quantify, for reduced operational or embodied carbon emissions. Likewise, it is important not to overlook the human health necessity of access to views through windows and daylight.
We know how to build high-performance building envelopes (Figures 8-10). We have proven products, installation processes and testing methods to do much better on every new building, and to effectively retrofit large numbers of existing buildings.
The construction market cannot be relied on to do what’s needed en-masse and cannot move fast enough without policy intervention. So, we must actively advocate to governments and standards organisations for the implementation of transformative codes and incentive structures addressing carbon, resilience and human health in the built environment.
Historically, at least in the U.S., the glazing industry has not proactively lobbied to drive to higher fenestration performance through incentives or increased stringency in codes. Contrast this with the lighting industry, which has lobbied and received an average of $25 million per year from 2007 to 2012 from the U.S. government to support solid state lighting research, development, and manufacturing. They have effectively cannibalized their incandescent and fluorescent products, and replaced them with new LED lighting technology. This allowed the lighting industry to reach early and late majority phases of U.S. LED market adoption in many applications in just seven years! Compare this to the slow speed of market adoption of fenestration technologies.
The U.N. officially designated 2022 as the International Year of Glass. Let’s use it as a platform to educate the international community on the current state-of-the-art in glass and glazing technology, and to advocate globally for its adoption as business-as-usual through more stringent codes and policy incentives. In doing so, we can do our part to put the world on a faster trajectory to resilient, healthy and net-zero carbon buildings. Let’s be leaders, not laggards.
Sir David King, former chief science advisor to the U.K. government and founder of the Centre for Climate Repair at the University of Cambridge, has stated, “What we do in the next five years determines the viability of humanity’s future. Even if we narrow our aspirations to ‘survival,’ fixing on a timescale of 50 years or so, the challenges are daunting. Humanity deserves better. We know what to do…”. Our industry knows what to do. Let’s do it.
CITATIONS and REFERENCES
 U.N. Intergovernmental Panel on Climate Change Sixth Assessment Report, 2021, https://www.ipcc.ch/report/ar6/wg1/
 T. Lenton, et. al., “Climate tipping points – too risky to bet against,” Nature, 27 November 2019, https://www.nature.com/articles/d41586-019- 03595-0
 C. Xu, T. Kohler, T. Lenton, J-C Svenning, M. Scheffer; “Future of the human climate niche,” Proceedings of the National Academy of Sciences, May 2020, 117 (21) 11350-11355; DOI: 10.1073/pnas.1910114117, https://www.pnas.org/content/117/21/11350
 “Flooded Future: Global vulnerability to sea level rises worse than previously understood,” ClimateCentral.org, 29 October 2019, https://www.climatecentral.org/news/report-flooded-future-global-vulnerability-to-sea-level-rise-worse-than-previously-understood
 A. Moses, “Collapse of Civilisation is the most likely outcome: Top climate scientists,” Resilience.org, 8 June 2020, https://www.resilience.org/stories/2020-06-08/collapse-of-civilisation-is-the-most-likelyoutcome-top-climate-scientists/
 U.N. Environment Global Status Report, 2017, https://www.worldgbc.org/sites/default/files/UNEP%20188_GABC_en%20%28web%29.pdf
 Urban Green Council, “Baby It’s Cold Inside,” February 2014, https://www.urbangreencouncil.org/babyitscoldinside
 N. Popovic and W. Choi-Schagrin, “Hidden Toll of the Northwest Heat Wave: Hundreds of Extra Deaths,” The New York Times, 11 August 2021
 British Columbia Coroners Service News, Heat-Related Deaths in BC, 30 July 2021,https://www2.gov.bc.ca/gov/content/life-events/ death/coroners-service/news-and-updates/ heat-related
 A. Ozkan, A.Z. Yilmaz, T. Kesik, W. O’Brien; “The Time-Based Metrics of Thermal Autonomy and Passive Survivability and their Correlation to Energy Use Intensity,” Interdisciplinary Perspectives for Future Building Envelopes ICBEST Istanbul, May 2017, https://pbs.daniels.utoronto.ca/faculty/kesik_t/PBS/Kesik-Papers/The-Time-Based-Metrics-of-Thermal-Autonomy-and-Passive-Survivability-and-Their-Correlation-to-Energy-Use-Intensity.pdf
 B. Levitt, M.S. Ubbelohde, G. Loisis, N. Brown; “Thermal Autonomy as Metric and Design Process,” presented at Pushing the Boundaries: Net Positive Buildings, SB13 Vancouver, 2013, http://www.coolshadow.com/research/Levitt_Thermal%20Autonomy%20as%20Metric%20and%20Design%20Process.pdf
 H. Sanders, “Reducing the Carbon Impact of Facades: Is innovation what we need?” Intelligent Glass Solutions magazine, Spring 2021, page 8, https://igsmag.com/market-trends/environmental/reducing-the-carbon-impact-of-facades-is-innovation-what-we-need
 H. Sanders, A. Blakeslee, A. Seah, V. Wardill, J. Del Toro; “Global connections: The correlation between code stringency and energy-saving technology adoption,” Parts 1-3, Intelligent Glass Solutions online blog series, June 2021, https://igsmag.com/market-trends/environmental/global-connections-the-correlation-between-code-stringency-and-energy-saving-technology-adoption-part-1/
 H. Sanders, A. Blakeslee, A. Seah, V. Wardill, J. Del Toro; “Hot Climates: Give us a break,”Intelligent Glass Solutions online blog, August 2021, https://igsmag.com/features/hot-climates-give-us-a-break/
 D. King and J. Lichtenstein, “Climate repair: three things we must do now to stabilize the planet,” The Conversation, 12 August 2021, https://theconversation.com/climate-repair-three-things-we-must-do-now-to-stabilise-the-planet-163990
Author: Helen Sanders, PhD, is a general manager at Technoform North America. She has 27 years of experience in glass technology and manufacturing, with expertise in functional coatings, insulating glass and thermal zone technologies for fenestration. She is a board member of the Façade Tectonics Institute and its founding president from 2017-2021. She is also a board member of the Fenestration and Glazing Industry Alliance (FGIA). She has a master’s degree in natural sciences and a doctorate in surface science from the University of Cambridge, England. She can be reached at firstname.lastname@example.org