In the years leading up to the present moment, the architectural design of facades in New York, San Francisco and around the United States has been flourishing while increasingly stringent energy code requirements have been resulting in progressively higher and higher facade performance. We may one day look back and see this period as a golden age of American architecture, where the context of a decade of stable economic growth and the emerging collective understanding of our global impacts on the environment combined with mature design technology tools being used by both designers and manufacturers. Cover photograph by Whitney Starbuck Boykin
The widespread societal and economic impacts of CovID-19 will certainly be an inflection point in this progression. At the time of writing this article, our society has been disrupted on a scale that few had imagined possible, and the future is in question. In a crisis that changes behaviors as fundamental as how we greet one another, it is easy to imagine that the events of the last months will cause a reassessment of priorities. What trends will emerge at the national and global scale? In a moment when so much that was unimaginable has already happened, it is time to reaffirm collective goals for the environment and continue expanding our understanding of how our individual projects fit into the larger whole of our global society.
California and San Francisco have consistently been leaders in driving forward energy efficiency for buildings. California passed its first energy efficiency policy, Title 24, in 1977, which has helped keep California’s energy consumption per resident stable since enactment according to the California Energy Commission, while the rest of the country’s energy consumption per resident has grown by 40%. San Francisco continued the trend of leading on environmental planning by establishing the Commission on San Francisco’s Environment in 1993, which enabled the city and community to pass The Sustainability Plan in 1997. The Sustainability Plan comprehensively addressed the multiple aspects of building a sustainable society, including energy consumption, and contains what I find to be one of the most succinct and complete definitions of energy sustainability:
Society will have reached sustainability in energy when it is living on the energy budget set by the natural supply of solar energy (harvested directly as sunlight converted to heat or electricity, or indirectly through wind, water or vegetation converted to fuel).
On top of the current California energy code requirements to meet or exceed ASHRAE90.1-2016, the Sustainability Plan sets goals to exceed those requirements by a further 25% and have on-site generation of renewable energy on every building.
While New York started later, it too has become a leader by forging a comprehensive plan to address climate impacts of global warming emissions and align its development with the Paris Agreement of 2015. New York City first established the requirement to have a citywide sustainability plan in 2008, and formed the Office of Long-Term Planning and Sustainability to guide and direct that effort. In 2014, Local Law 66 was passed, committing the city to reducing citywide emissions by 80% by 2050. In 2016, New York City’s Roadmap to 80 x 50 was published, describing the many aggressive improvements that are needed to achieve the overall goal of emissions reductions. It notes that more than 68% of city greenhouse gas emissions come from the energy used to power, heat and cool buildings, making it clear that improved performance from the façade is key to successfully meeting the 80 x 50 goal. Most recently, the Climate Mobilization Act of 2019 enacted building performance mandates for large buildings (with financial penalties for those that do not comply), importantly focusing attention for the first time in New York on the energy use intensity of a building (EUI) and the resultant greenhouse gas emissions from that energy use. The act further requires building energy efficiency grading and energy labeling, financing for clean energy upgrades, and green roofs, solar panels, or a combination of the two on all new buildings. Combined with the NYC Energy Conservation Code adopting the “stretch” provisions of the state energy code including the most recent adoption of ASHRAE 90.1-2016 as baseline performance, the planning from the first half of the decade has rapidly moved into implementation with real impact.
Within this context of ever improving performance, the design aspirations of owners and architects has been thriving in both cities. As illustrations of this trend, three recent projects stand out for the combination of design and performance, two in New York City and one in San Francisco.
Nike House of Innovation 000
Nike’s new flagship store in New York City completed in November 2018, covers 68,000 square feet over 6 levels in the podium of an existing tower on 5th Avenue. With Nike Retail Design Global as the designers and CallisonRTKL as the architect, the instore experience was designed to highlight innovation, environment, and service. The façade features custom carved and slumped low-iron insulating glass units fabricated by Cricursa in Spain, and unitized and installed as part of a high-performance façade system by Seele. Organized around a 5-story atrium and anchored to the roof, ground and the corner staircase, the façade gives the space a dynamic sense of activity and energy. During a research and development phase for the innovative glass, preliminary engineering was necessary to confirm both structural and thermal performance of the façade. Technology to slump the curved glass with a low-e coating was not available, or would darken the façade more than acceptable architecturally. The solution was to combine the curved outer-lites with flat inner-lites that could include a high-performance low-e coating. The glass is thus able to achieve the thermal performance to meet the New York City Energy Conservation Code, and be the transparent beacon façade that Nike sought for its flagship.
Nike House of Innovation 000. Photograph by Whitney Starbuck Boykin
50 Hudson Yards
Scheduled for completion in 2022, 50 Hudson Yards is surrounded by the public plaza of the boulevard, the rows of traffic along 34th Street and 10th Avenues, and the other towers of the Hudson Yards neighborhood in New York. Designed by Foster + Partners and developed by Related Companies, the project will be 985 ft tall, will enclose 2.9 million gross square feet of open-floor office space with floor to ceiling glass and up to 60’ wide open column bays, and is expected to achieved LEED-Gold.
Rendering of 50 Hudson Yards courtesy of Related-Oxford
The custom high-performance curtain wall features a lively white granite cladding that traces the structural grid of columns and beams from the ground to the top of the tower. At the east and west elevations, the façade projects out from the stone grid, requiring units at the top of the bay to “scoop” back to align with the recessed face of stone, all without impacting performance or the interior floorplan. Occupants enjoy views out of floor to ceiling glass, with just under 60% vision glazing for the project. Given the high level of vision area, it was critical to coordinate accurate solar shading and system u-factors for the curtain wall into the energy model early in the design process. After reviewing many glass samples, Interpane glass with a high-performance low-e coating was selected that balanced needs for shading, visible light transmission, and color neutrality. Preliminary thermal modeling was used to confirm u-factor targets were realistic, and then corroborated by full thermal model submissions by the curtain wall contractor, New Hudson Facades.
Uber Headquarters
Designed by SHoP Architects and being completed in 2020, Uber’s new global headquarters is composed of two iconic buildings situated in San Francisco’s rapidly developing Mission Bay. The highly transparent buildings frame a small park, retain public corridors through the site, and are connected by multiple glass bridges that allow pedestrians to pass between them at various floors. In contrast to a conventional office typology, the two buildings are organized around an immense interior space known as the Commons. Running the entire height and width of one of the facades on each of the buildings, this company-sized gathering space is enclosed by a glass skin with fully operable curtain wall components fabricated by Gartner Permasteelisa that puts San Francisco’s temperate climate to best use. Supported by Vierendeel trusses that span the building’s height, massive pieces of low-iron glass provided by Interpane were designed to set within operable frames and fold towards the exterior of the building, allowing fresh air in and uninterrupted views out. Because the Commons is only partially conditioned, in a high seismic zone, and designed at a monumental scale, it required close coordination between all parties involved.
Rendering of Uber Headquarters courtesy of SHoP Architects
The COVID-19 pandemic has disrupted the national and world economies that support and underlay architectural projects like those just mentioned. The contagiousness and asymptomatic presentation of the virus along with the intensity of our global transportation networks has allowed it to spread around the world. Its severity has reminded us that health is primary, that no activity can proceed unaffected when a significant percentage of the population are at risk of illness or death.
Few of us could have imagined the effects as the world economy has “paused”. Our governments, healthcare systems, and health research institutes have rapidly transitioned and re-deployed their resources to focus on mitigating the impacts of the wave of infections, improving treatments, and finding a cure. Our schools are teaching using online and remote learning platforms. Our work has been categorized as essential and nonessential, and transitioned to remote platforms wherever possible. Demand for crude oil and gasoline plummeted, there are signs that overall electricity demand decreased, and air pollution cleared from the skies of major metropolitan centers around the world.
The pandemic’s sudden reduction of global energy consumption and greenhouse gas emissions reaffirms our ability to control the inertia of our collective action in a time of crisis. Further, the pandemic’s varied responses from governments and cultures around the world reminds us that global problems and goals such as limiting the spread of a contagious virus, or the use of fossil fuels, require global solutions across multiple sectors and borders. Comprehensive environmental plans like San Francisco’s Sustainability Plan and New York City’s Roadmap to 80 x 50 are clear frameworks for the type of coordinated actions required to successfully achieve these desired outcomes.
As façade designers and builders, we are ready to imagine and realize higher performing building enclosures that achieve the goals of these plans by employing tools and practices centered around performance.
Structural and thermal engineering methods have been transformed over the last two decades by performance-based computational modeling facilitating efficient designs. Faster and more detailed finite element analysis lets the designer test more iterations and identify how to best organize and assemble components. Similarly, building energy modeling is now used as a design tool, helping focus design efforts onto the aspects of a project that have the largest environmental impact early in the design process to find achievable and in-budget solutions.
The use of performance specifications for procurement of facades is another important driver of innovation. By clearly documenting the design criteria, loads, and conditions under which an architectural design is to perform, a performance specification requires the façade contractor to provide a façade system that meets the specified performance, rather than to provide a particular product. That in turn frees the contractor to propose, test, and utilize novel material and assembly solutions limited only by the evolution of technology and their own ingenuity.
Performance testing and field verification by a building enclosure specialist help identify deficiencies in execution, ensuring that the building enclosure will perform as expected. Building enclosure commissioning first mandated by institutions building their own buildings and then prescribed in voluntary standards like LEED, is now also appearing in energy codes like New York City Energy Conservation Code of 2020. By codifying the practice of verifying performance through review, testing, and inspections, building enclosure commissioning is helping more buildings to meet their performance goals. There are however many aspects of building sustainably that are outside the direct control of designers.
As designers, we don’t set the energy conservation code requirements, or building energy use intensity (EUI) targets. And while voluntary standards have helped, it’s clear that a building owner’s construction decisions are controlled by the economic realities of building that drive towards efficiency, not sustainability or resiliency. We can help however by embracing the ever changing and improving performance requirements of energy codes, helping our clients understand the important role that the codes play in reaching the overall goals of a sustainable and healthy built environment. And we can provide feedback to the code committees and government advisory groups, providing insights onto how particular aspects of the code are or are not working as intended.
We know that the conversion of the electrical grid to renewables is critical to reaching fossil fuel reduction targets at regional, national and global levels. But we don’t control how the energy consumed in our projects is generated. We can however support government and private initiatives for research of new renewable energy technologies, and the subsequent rollout of the successful, scalable technologies into diversified electrical grids.
Finally, we do not have a full accounting of the climate warming emissions generated to fabricate and transport the materials used to build our projects, or the energy consumed during construction. Programs like the International Environmental Product Declaration (EPD) System initiated in Europe are publishing transparent, verified and comparable information about the life-cycle environmental impact of products. These declarations are an important first step and should continue, but the accounting process is complicated and difficult, it does not include energy used for construction, and the information alone is not sufficient to drive selection towards environmentally friendly products. A simpler method for the designer to take these embodied costs into account would be an economic one, where the environmental cost of any given product or service is accurately priced into the financial cost of a that product or service. With the World Bank reporting that just over 20% of greenhouse gas emissions are covered by either emission pricing or emission trading systems (ETS) like cap-and-trade, we are making progress here too. But the conspicuous absence of the United States, along with Russia, the Middle East, most of Africa, and other developing countries expresses the geo-political difficulties of setting up global regulations. Until internationally coordinated pricing programs are widely adopted, we will be reliant on voluntary and local initiatives to lead. As designers and builders, it is critical that we support and encourage these efforts.
We are still in an uncertain moment, where the ending of our story is unknown. Basic health safety and the risks of returning to school and work are still questions, leaving the immediate economic future in doubt. And the reasons for which we advocate for environmental causes at times seem conflictual—does one prioritize energy conservation or energy independence, environmental protection, social justice, or economic growth? But the reasons for optimism are clear. We have formed underlying institutions to focus political and industry efforts and enact meaningful and effective changes in local codes and regulations. We are re-thinking our environmental situation holistically in frameworks like The Sustainability Plan and The New York City Roadmap to 80 x 50, in ways that combine and align the above motivations rather than letting them remain as oppositions. And we have the tools and practices at our disposition to design and execute higher-performance facades. What remains is a question of desire: what future do we want to build together?
This article was originally published in IGS Magazines Summer 2020 USA Special Edition: Read the full Magazine here for more thought-leadership from those spearheading the industry
Author: Daniel Vos, Principal at Heintges Consulting Architects & Engineers
Daniel Vos, AIA, joined Heintges in 2004 and has collaborated on many high-profile building facades in New York and around the world. His expertise in structural glass design and knowledge of building envelope energy performance contribute to the realization of innovative and environmentally responsible building enclosures. Mr. Vos studied architecture in Paris and New York and teaches at Columbia University GSAPP where he is an Adjunct Assistant Professor of Architecture.