On November 9, Facades+ is headed to Boston for a full-day conference. The conference features a range of facade specialists and manufacturers, ranging from stone fabricator Quarra Stone to Boston's very own designLAB Architects. Chris O'Hara, founding principal of Studio NYL, and Rishi Nandi, associate at Perkins + Will, are co-chairing the event. With decades of experience across the globe, both firms have been recognized with design awards for their advanced enclosure systems and finely executed architectural preservation projects. To learn more about what the two practices are up, AN interviewed the two co-chairs on the complexities of architectural preservation, environmental performance, and digital fabrication. The Architect's Newspaper: Both Perkins + Will and Studio NYL have been involved in numerous preservation projects. Could you expand on the difficulties of bringing historic structures up to contemporary standards, blending new design elements with the old, and the opportunities present with these projects? Rishi Nandi: The revitalization of historic buildings is challenging but pays great dividends. These buildings often represent something well beyond the program they house to their communities. Approaching the projects in a manner that is responsive to the neighborhood’s needs is critical since the structures often embody the resilience and stability of the communities they are embedded within. The most difficult part of any restoration is making sure the improvements you are making do not have any unintended consequences. For instance, many historic structures breathe differently than today's facade systems. This becomes a significant issue when one considers improving the performance of the envelope through insulation and air barriers. Understanding the hygrothermal properties of the walls is critical to ensure that potential compromising events like freeze-thaw do not occur. Matching old with new is also critical. We simply do not make component pieces the same way they were when many of these buildings were built. For example, no one is field fitting and assembling windows on site to conform to glazing dimensions that are all slightly off. The good news is that mass manufacturing is changing rapidly and customization options that did not exist in the 1980s have proliferated. We are often now able to work with fabricators in a hands-on way to create matching components that can replace those that we have to. By this, I mean that the first option in our approach is to rehabilitate as much as we can. Some of this is driven by the aesthetic. The majority of this, however, is driven by the consideration that the reuse of the existing structure and envelope has a significant environmental and social benefit. In these scenarios, we are able to keep intact the community's connection to the identity of the structure while significantly reducing the carbon footprint of the building through the reduction of primary materials. Chris O'Hara: Existing and historic buildings are a fantastic challenge. As we are always discussing sustainability, and it generally focuses on energy performance and recycled materials, it pales in response to what we can do by saving the embodied energy of an existing structure and breathing new life into it. Taking that existing structure that is either of an age where insulation was not considered and thermal comfort was managed through thermal mass and passive means, and mixing it with modern mechanical systems relying on a reduction of air exchanges–or worse yet a building designed with modern mechanical systems but an ignorance of envelope due to cheap energy–requires more analyses and more clever solutions. Management of the thermal performance of the existing building while trying to take advantage of the systems' drying potential is fun. Getting these buildings to perform at a high level is likely the most good we can do as a facade designer. What do you currently perceive to be the most exciting trends in facade design that boost environmental performance? RN: There are a lot of great products on the market including nanogel insulations, fiber reinforced polymer (FRP), and advances in glazing. That being said, as an architect, I have a tough time understanding the environmental impact of our products. We need better data from manufacturers that tell us clearly the waste stream. We need to know how much water is being used to make the products. Manufacturers should be required to help us better understand the life cycle carbon footprint of the products we are using. This information should be mandatory and should be directly influencing the way we make product selections and decisions. We can then have a more informed discussion on environmental impacts and, hopefully, then come up with a strategy on how to begin to address the concerns addressed within the Intergovernmental Panel on Climate Change (IPCC)’s most recent report. CH: Fiber reinforced polymers (FRP) and vacuum insulated systems. For the FRP, our ability to more cost-effectively thermally break and structure our faces with nearly thermally inert materials opens up possibilities in how we build. Vacuum insulated glass and vacuum sealed nanogel insulation are offering the ability to drastically improve our system U values while thinning down our assemblies. Although these technologies are still new to the market and come with a cost, like all other advances we have seen in the last 20 years or so I expect that cost to come down as we find how to use these systems more efficiently. Digital fabrication offers incredible possibilities for the mass production of individual facade components. In your experience, how is this technology reshaping the industry and your projects in particular? RN: Technology is reshaping our approach. Digital fabrication workflows are being created that are beginning to bridge the gap between documentation and fabrication. Working from a common platform has a number of benefits including allowing for a more detailed conversation on material applications and efficiencies. Robotics and digital printing allow us to create the right responsive materials that maximize the material return while minimizing waste. This increased communication is pushing more and more early involvement from manufacturers. We have employed modified delivery methods such as the integrated design process and design assist to help engage fabricators earlier to better our designs, drive a level of cost certainty and work within proprietary systems that help minimize team risk. The result is a blurring of traditional lines. The next step to me is a disruption in the way we work. We are already starting to see it with companies like Katerra, who with their digital platform are looking for ways to deliver entire projects at all phases from design to construction completion using prefabricated components and an integrated approach not yet seen by the industry. It will be interesting to see how things develop over the next 15 years and the types of efficiencies that may be gained and what it means for the way we all work and deliver projects. CH: The use of digital fabrication seems to have found its way into most of our current enclosure projects, although the aesthetic is not always driven by the technology. We have found that the speed and precision it affords makes it an important part of our toolbox. Whether it is used for an elaborate cladding geometry or for the precise fabrication of repeated parts, it has really opened up the possibilities of what we can achieve while still being conscious of the parameters of schedule and cost. To do this the designer needs to understand the craft that goes into this work. Many do not understand that even with the technologies available there is still craft. The difference between this and a carpenter is simply what is in the tool belt. Further information regarding the conference can be found here.
Posts tagged with "carbon footprint":
Last week, District of Columbia councilmember Mary Cheh introduced the Clean Energy DC Act of 2018, legislation that, if enacted, would require 100 percent of the electricity sold in the District to come from renewable sources by 2032. The act also specifies new guidelines for retrofitting existing buildings that emit substantial greenhouse gases into more energy efficient structures. The bill must be reviewed by committees before a vote takes place, which would probably happen sometime in the fall. In the wake of the United States' withdrawal from the Paris Climate Agreement, many U.S. cities have set their own sustainability goals, and the attempts have taken various forms, including a pledge by Saint Paul, Minnesota to make all of its buildings carbon neutral by 2050. Under the watch of D.C.'s Department of Energy and the Environment (DOEE), the New Building Emissions Standards proposed by the act would regulate the energy performance of the District's buildings and introduce benchmarks for future construction. Regulations would include cover energy usage and energy efficiency, among other topics. An incentive and financial assistance program would be set up, while penalties would be issued for buildings that fail to comply. Cheh’s office told AN that the act does not intend to create prescriptive policies aimed at restricting the building industry, but the Washington, D.C., chapter of the American Institute of Architects (AIA|DC) expressed that that is a concern. They note that the current proposal "contains ambiguity and leaves the setting of performance criteria up to D.C. DOEE staff without clear opportunity for stakeholder input,” according to an earlier comment. “The legislation puts a large administrative burden on D.C. DOEE staff to set the standards, track compliance, and enforce the requirements of the program," said the AIA|DC in a statement. "The mandate for private property owners to upgrade existing building systems and performance without accompanying financial assistance could be problematic, leading to legal challenges and potentially adversely impact development.” Despite these comments, the AIA|DC said that it is proud that the city intends to lead the nation in setting a new standard for clean energy. This is not the first time that Washington’s building sustainability efforts have come under the spotlight. Last year, the city was dubbed the “quiet capital of sustainable design” by Huffington Post. They reported that in 2016, the city’s volume of certified green buildings per capita was almost eight times that of Massachusetts, and over 11 times the average for the top ten greenest states. D.C. was later named the world’s first LEED Platinum City in recognition of the city’s efforts in reducing greenhouse gas emissions and promoting clean energy in the built environment. One innovative green building currently under construction in D.C. is the American Geophysical Union (AGU) Headquarters. Its “net zero” design means it generates as much energy as it uses. Design features include a photovoltaic array, a radiant cooling system, a green wall, a direct current electrified grid, a water reclamation cistern, and a municipal sewer heat exchange system. The building is seeking the Net Zero Energy Building (NZEB) Certification by the International Living Future Institute.
Saint Paul, Minnesota has set an ambitious goal to reduce its carbon footprint by making all public buildings carbon neutral by 2030 and all private buildings carbon neutral by 2050, as first reported by Twin Cities Pioneer Press. St. Paul officials found that 52 percent of all carbon emissions were related to structures and the energy needed to power, heat, and cool buildings, according to Pioneer Press. Another 37 percent derived from transportation-related emissions. In an effort to encourage a reduction in a building’s carbon footprint, St. Paul has created a competition for private building owners called “Race to Reduce”. Participants monitor and compare their energy use to comparable structures across the city. The city council also recently approved a resolution that outlines general goals such as inspiring a culture of energy stewardship, working with major institutions such as colleges to set energy goals that align with the city, and promoting efficiency in large buildings. Another key aspect is lowering the energy burden on low-income households, ensuring that no household spends more than four percent of its income on energy costs, said Russ Stark, St. Paul’s chief resilience officer, to Pioneer Press. Small changes such as switching off air conditioning at night, as well as buying more renewably-sourced energy from community solar gardens, will help the city achieve its goal. Under the Trump administration and its decision to pull out of the Paris Climate Agreement, cities around the U.S. have been setting their own clean energy goals and emission reduction projections. St. Paul joins cities like Seattle and Boston, which have both declared a goal of becoming carbon neutral by 2050. Former New York City Mayor Michael Bloomberg has pledged $4.5 million to help cover the U.S.’s commitment to the Paris climate agreement.
This is an article from our special November timber issue. We like to blame a lot of things for climate change—namely coal and cow farts—but if we were to search for a worthy scapegoat, architects might end up looking in the mirror. The building sector is responsible for 44.6 percent of U.S. carbon dioxide (CO2) emissions. And, with an estimated 1.9 trillion billion square feet to be built in the next 33 years, those emissions will not subside without significant intervention. On the flip side, for architects anyway, this means the power to reduce carbon emissions is quite literally in your hands. “No designer—I think—wakes up and says, ‘I want to make the world worse today,’” William McDonough, architect, designer, and sustainable development leader said. “To make the world better, that’s our job.” Identifying successful ways to build sustainably can be difficult in a haze of greenwashing and checklist-style certifications, but many environmental experts, architects, and scientists are looking to mass-built timber as a reliable way to reduce carbon and fossil fuel output. A recent study, “Carbon, Fossil Fuel, and Biodiversity Mitigation with Wood and Forests,” stated that using wood as a building-material substitute could save “14 to 31 percent of global CO2 emissions and 12 to 19 percent of global FF [fossil fuel] consumption by using 34 to 100 percent of the world’s sustainable wood growth.” Building with timber reduces the overall carbon footprint in several ways. First, wood is a renewable resource, and growing a tree is a low-impact method of production (i.e. it uses photosynthesis rather than a plethora of machines). Second, trees are grown in abundance all over the United States and don’t need to be imported from abroad, reducing the amount of energy expended on shipping. “Right now we harvest less than half of what we could and still be well within the threshold of sustainability,” Kathryn Fernholz, the executive director at Dovetail Partners, an environmental nonprofit, explained. “That’s not the same in every single scenario, but in general in the U.S., we have an abundance of wood.” Third, and perhaps counter-intuitively, many environmentalists believe that harvesting trees allows forests to become more efficient at carbon sequestration. The logic is simple: When a tree is harvested, it stores carbon, then when another tree is planted in its place, it also will store carbon, making that plot of land’s carbon sequestration infinitely multipliable as trees are planted, grown, and harvested. “There is a widely held belief that cutting down trees is bad and causes loss of forest, but a strong market for wood products would cause us to grow more forests,” Fernholz said. “The vast majority of deforestation is land conversion, using the land for something else like development or agriculture. We know what resources we have and we monitor them and adjust. Forestry is not in the same place it was a hundred or even fifty years ago when deforestation was an issue.” While that stance of de-and reforestation is under debate among environmental experts, across the board, timber is generally a more sustainable building material because it is a renewable resource (provided that responsible forest practices are used). This includes the energy consumed to produce cross-laminated timber (CLT) in factories, which have a carbon emissions advantage over steel because the wood does not need to be heated over 2,700 degrees Fahrenheit like steel or concrete—in fact, unless the wood is kiln dried, heat isn’t need at all. Although embodied carbon is typically measured per building, because different amounts of each material are used in different scenarios, Wood for Good, a campaign by the timber industry to promote the material, claims that a ton of bricks requires four times the amount of energy to produce as a ton of sawn softwood (wood used for CLT); concrete requires five times, steel 24 times, and aluminum 126 times. “Reporting carbon emissions for wood includes a range of different assumptions and methods,” explained Kathrina Simonen, an associate professor of architecture at the University of Washington and director of the Carbon Leadership Forum. “So sometimes it ends up negative and sometimes it ends up positive. It can be confusing.” She is optimistic, however, that research is close to resolving the differences. Responsible forestry practices are already underway, with harvest occurring on long rotations so that the forest has time to regenerate itself and care can be taken to avoid removing other plants, roots, and branches in the process. Lastly, “Wood can be a durable good, as we've seen in ancient wooden buildings like the Temple at Nara, Japan [originally built in 745 AD and rebuilt in 1709],” McDonough said. “In [wood’s] history, it is often put into a cycle of use and reuse that can take it from large numbers to smaller and smaller [components].” Its ability to withstand centuries and to be disassembled and then reassembled into other buildings and furnishings keeps it out of the landfill and in a perpetual cycle of use until it can ultimately be returned to the environment in some form. Although well over 90 percent of one-to-three-story residential buildings are already wood-built, there are only a handful of mid-rise and tall timber buildings across the United States, a result of building codes that often prohibit timber-built structures larger than four to six stories. However, thanks in part to innovative wood products, including CLT, nail laminated timber (NLT), and glue laminated timber (glulam), wood construction can be used in buildings as tall as 40 stories. A study by consulting and engineering company Poyry and the New England Forestry Foundation shows that the greatest potential for timber-built is in mid-rise (six to 14 story) buildings, as it also tends to be more economical to build with timber at that scale. According to the Soft-wood Lumber Board, over two-thirds of the square footage in the mid-rise sector could be made with mass timber. These statistics combined, in addition to the taller structures that mass timber can create, have the potential to make a sizable dent in our CO2 and fossil fuel emissions. Like virtually everything in architecture, though, it is all in the details; for timber to be sustainable it has to be done correctly, from responsible forestry practices to environmentally safe glues and binders to craftsmanship and the design itself. “It is tremendously exciting. Building with wood creates diverse opportunities—there are different species and materials that all can work,” Fernholz said. “However, it is important to recognize that some things can come from wood, but nothing replaces good design and planning.”
University of California, Berkeley has released a new set of interactive maps illustrating national energy usage. The visually striking if troubling images reveal a stark urban/suburban divide regarding carbon footprint, with the latter contributing far more in emissions than their city-dwelling counterparts. Average Annual Household Carbon Footprint (Source: UC Berkeley CoolClimate Network (2013) The maps were produced as part of the school's CoolClimate Network. The three correspond to average annual household carbon footprints, household energy carbon footprint, and vehicle miles traveled respectively. Hovering your mouse over a particular region allows for a more detailed breakdown of the three categories. The data suggests an inverse relationship between population density and carbon footprint size, which is to say that more densely populated cities tend to be more energy efficient. A further look at the numbers suggests that much of this correlation can be explained by the high transportation costs pervasive in suburbia. Average Household Energy Carbon Footprint (Source: UC Berkeley CoolClimate Network (2013) Yet before New Yorkers or any other urbanites grow too smug, the net effect of this relationship may be largely null. The denser cities that demonstrate a relatively lower carbon footprint tend to be the very areas that spawn the extensive suburbs possessing problematically higher ones. The correspondence between usage and population density is not applicable when only suburbs are taken into account, and in fact the opposite correlation tends to be true. Researches claimed that this finding can be explained largely by economic factors. Curious users can see how their household stacks up against their own neighbors or any other region in the country by filling out the Network's CoolClimate Carbon Footprint Calculator. Average Vehicle Miles Traveled by Zip Code (Source: UC Berkeley CoolClimate Network (2013)