Archive for the ‘Sustainability’ Category
Elemental is proud to announce that it’s award-winning historic reconstruction of Shepard Hall at The City College of New York is included in the current exhibition on view at the Center for Architecture in New York City as part of the month-long celebration Archtober. The exhibition explores how critical choices and consumption patterns of professionals and building occupants can make positive energy changes in our cities. Shepard Hall was selected as an exemplar of sustainability in historic reconstruction. his is particularly evident in considering the use of Glass Fiber Reinforced Concrete (GFRC) as the primary reconstruction material, in lieu of other materials.
The project’s 72,000 units of replicated terra cotta – the largest terra cotta replacement project in the world – yields an embodied energy savings by using GFRC of approximately 29,880,000,000 Btu or the equivalent of about 207,000 gallons or about 4,900 barrels of #6 oil when compared with cast stone and approximately 57,600,000,000 Btu – the equivalent of about 400,000 gallons or about 9,500 barrels of #6 oil – when compared with terra cotta.
In addition, in considering just the energy savings in transportation of the much lighter GFRC, the 72,000 units of replicated terra cotta, the savings in the weight of material that must be fabricated, transported to the building, lifted and installed is 14,400,000 pounds – or 7,200 tons.
Here is how we arrived at the findings in savings. Information on the embodied energy of various materials is from the Handbook of Energy Use For Building Construction prepared for the US Department of Energy by Elemental’s Carl Stein and the late Richard G. Stein:
EMBODIED ENERGY and WEIGHT OF MATERIAL COMPARISON
The analysis examines two alternative systems for replacing decorative, cast masonry units – thin shell glass fiber reinforced concrete and cast stone. Cast stone is used for the solid alternative because there is limited embodied energy data available glazed terra cotta, the original material and, at other buildings on the CCNY campus, cast stone has been used to replace deteriorated terra cotta. Note, however, that structural facing tile – a clay-bodied vitreous-glazed unit masonry product that is similar in composition to glazed terra cotta – has an embodied energy of about 860,000 Btu/ft3 as compared with that for precast concrete which is approximately 318,000 Btu/ ft3
The exterior reconstruction of Shepard Hall was the first large-scale use glass fiber reinforced concrete (GFRC) – thin shell units for historic preservation. This greatly reduced the quantity and weight of the replacement cladding as well as achieving a number of technical goals such as accommodation of thermal movement
Currently, more than 65,000 damaged terra cotta units have been replaced. When complete, the total will be approximately 72,000 units. As a frame of reference, GFRC (Glass Fiber Reinforced Concrete), with an average wall thickness of ¾” is compared with cast stone (precast concrete) having and average thickness on 6” including the complex molding and sculpture.
Embodied energy in precast concrete is 318,000 Btu/ ft3.
Average face area per unit is approximately 3 ft2
Volume of GFRC is 0.19 ft3
Embodied energy for GFRC is approximately 60,400 Btu/unit
Volume of cast stone is 1.50 ft3
Embodied energy for cast stone is approximately 477,000 Btu/unit
GFRC saves approximately 415,000 Btu/unit (average) when compared with cast stone.
Note: this does not include the embodied energy in the polymers and matakaolin that would be added to both materials, increasing the embodied energy savings for GFRC; however, it also does not include the Alkali Resistant glass fiber reinforcing (approximately 4½% of the total weight) which would apply only to the GFRC. If the embodied energy in the glass reinforcing is similar to that in conventional glass fiber, it would be about 6,500 Btu/pound or about 9,000 Btu per unit. In other words, even discounting the fact that there would be significantly more polymer and metakaolin in the cast stone, the addition of about 9,000 Btu of reinforcing results in the saving of about 415,000 Btu of concrete
The 72,000 units of replicated terra cotta for the entire project yield an embodied energy saving for GFRC of approximately 29,880,000,000 Btu (the equivalent of about 207,000 gallons or about 4,900 barrels of #6 oil) when compared with cast stone.
Using the embodied energy for structural facing tile to represent that of glazed terra cotta gives the following analysis:
Difference in volume of concrete between GFRC and terra cotta is approximately 1.0 ft3/unit. (The cellular construction of the terra cotta body allows it to made with somewhat less volume of material than with cast stone
Volume of GFRC is 0.19 ft3/unit
Embodied energy for GFRC is approximately 60,400 Btu/unit
Volume of terra cotta is 1.00 ft ft3/unit
Embodied energy for terra cotta is approximately 860,000 Btu/unit
GFRC saves approximately 800,000 Btu/unit (average) when compared with terra cotta
The 72,000 units of replicated terra cotta for the entire project yield an embodied energy saving for GFRC of approximately 57,600,000,000 Btu (the equivalent of about 400,000 gallons or about 9,500 barrels of
#6 oil) when compared with terra cotta
Weight of Materials:
Although not directly convertible to energy quantities, it is also instructive to consider the weight of materials that must be handled in the reconstruction process. At 1.5 ft3/unit, the average cast stone unit weighs 225 pounds. At 0.19 ft3/unit, the average GFRC unit weighs 28 pounds. The weight saving for GFRC when compared with cast stone is +/- 200 lbs/unit.
For the 72,000 units of replicated terra cotta, the savings in the weight of material that must be fabricated, transported to the building, lifted and installed is 14,400,000 pounds – or 7,200 tons.
In a recent posting on BuildingGreen.com, “Does Saving Historic Buildings Really Save Energy?” Tristan Roberts pointed out a number of benefits that may be realized by the adaptive reuse of older buildings; however, he dismissed the notion that there is value in the energy embodied in these structures. While he is correct in his assertions about the cultural and urban value of historic buildings, he misses the point, or at least part of the point of the value of the energy embodied in those buildings. Despite the fact that there is no way to “recover” the embodied energy in old buildings, if their reuse offsets the need to build replacements, the energy that would have been embodied in those new buildings is saved – avoided cost.
Of course, there will almost certainly be some construction, and therefore some energy commitment, required to extend the useful life of older buildings including implementation of measures to significantly improve performance. The net avoided energy cost will be less than the total energy cost on the new building. Nonetheless, the new energy that must be “embodied” into the existing building will typically be 1/3 to 2/3 that of starting from scratch. Additionally, there is that much less debris sent to landfill and that much more “embodied” culture carried forward.
This is not to say that saving older buildings will always be the best choice for the environment, nor is it saying that one should only consider saving important historical buildings if their continued existence can be justified through energy savings or other environmental benefits. The considerations will be based on a sliding scale. At one end, there are the truly significant historical and cultural artifacts that must be preserved at all costs. At the other end, there are the purely utilitarian structures whose continuance will be determined by quantifiable, pragmatic concerns. In the middle is that vast majority of buildings that make some contribution to the understanding of history and sense of place, and whose reuse will offset some portion of the embodied energy that would otherwise by required for new construction. These are buildings that are neither historically and culturally indispensable, nor clearly justified by environmental imperatives. In some cases, the positive attributes embedded in these structures will be outweighed by benefits that can only be achieved through new construction.
Decisions regarding adapting and reusing instead of demolishing and replacing should be informed by multiple factors; some environmental, and some, as Roberts noted, cultural. What is critical, however, is that all significant considerations be included. This is particularly true for those middle ground buildings for which no single criterion is likely to prove decisive. While it’s true that embodied energy itself is not a recoverable resource, it is a valuable asset that can offset the need to expend new energy resources. And, while it’s unlikely that the energy offsets inherent in building reuse will be the sole determining factor in deciding whether or not to save a building, it is a real consideration that may push the eventual decision in one way rather than another. To exclude this asset from the equation is to neglect a readily exploitable and relatively benign resource. To knowingly neglect such a resource at this point in history would be irresponsible.
We highly recommend visiting friend and colleague, James Lewis' Datum International . While relevant in regards to current events, the site also offers valuable insight and is closely connected to Elemental Architecture's goals.
A Brief Recap of Last Night’s Inaugural AIANY Oculus Book Talk Series with Carl Stein at New York City’s Center for Architecture
As reported by Maxinne Rhea Leighton, Assoc. AIA:
Carl Stein, FAIA’s Greening Modernism: Preservation, Sustainability and the Modern Movement (W.W. Norton & Company, 11.29.10) offers a compelling and insightful argument for a creative and enthusiastic reexamination of the interconnection between modern architecture, sustainability, historic preservation, and green strategies. One of the many things that sets this book apart from others on architecture and sustainability is the way in which Stein unfolds the theoretical, instructional, and pioneering tenets between design and technology from the pre-petroleum to late-petroleum eras, suggesting opportunities for architecture in a post-petroleum world.
“A sustainable future,” writes Stein, “one in which humankind will have a place in the ecosystem of the Earth, depends on a fundamental reconsideration of how we utilize all of the resources that support the qualities of our lives.” The second greatest end-use energy consumer is infrastructure construction, and there is a dire need to upgrade this part of American society. As you read Greening Modernism, you, too, will be reminded that as much as the truth sounds good on paper, the hardest part is to convert these ideas to the politics of choice and economics. While architects have their challenges set out before them, Greening Modernism will be a hearty and generous companion for those who are willing to challenge what they value in themselves and consider to be the nexus of design, quality of life, and a sustainable global future.
Note: This was the first of a monthly series of book talks hosted by the AIANY Oculus Committee.
Maxinne Rhea Leighton, Assoc. AIA, is a member of the AIANY Oculus Committee. She is a business development, public relations, and marketing professional in NYC and Washington, D.C. Her expanded project base includes cause-related marketing, and the integration of social media with traditional-based forms of communication for non-profit and cultural institutions.
Last Thursday, December 9th, Elemental hosted the launch party for principal founder Carl Stein’s new book “Greening Modernism”. Tom Stoelker of the Architect’s Newspaper writes:
Bodacious bourbon pours complimented savory vittles at the yet-to-be-opened Hudson Clearwater in Greenwich Village last night. The restaurant’s first event launched Carl Stein’s new book, Greening Modernism: preservation, sustainability and the modern movement (W.W. Norton, $60.00). The affair had a decidedly down to earth flavor, though the elegant crowd resembled intermission at The Met. The venue seemed a natural fit for Stein of Elemental Architecture, since Elemental’s John Barboni designed the space using salvaged material culled from the 180-year-old carriage house.
“From my perspective, it fits into all the themes of the book,” Barboni said from behind a kitchen counter made of the structure’s former floorboards. “Green is not a newfound subject for Carl.”
From atop a small flight of stairs Stein thanked his family and colleagues, then settled in with the band to play banjo.
Mr. Zeller writes in his NY Times “Green” Blog post “When Green Building Is Not Green Enough” that “the nation’s building stock plays a bigger role in energy consumption and greenhouse gas emissions than many Americans might realize.” This is only true (a) because many Americans have chosen to ignore information that has been widely available for at least four decades and (b) powerful business and social interests have conducted a massive campaign of misinformation in order to maintain positions of economic and political power.
In 1972, the Club of Rome published the highly regarded Limits to Growth stating that by the first decade of the 21st century, the approaching limits to the availability of finite resources including energy would have profound effects on our lives, most of them being negative. In 1977, Richard Stein’s book Architecture and Energy documented that over 40 percent of all energy use in the US was closely affected by architectural decisions. In 1972, the American Institute of Architects, a very mainstream organization, began a detailed investigation into the relationship between building and architecture and in 1974 issued Energy and the Built Environment: A Gap in Current Strategies.
In 1981, the AIA issued Energy and Architecture, the first in a series of documents directed toward the design professions which eventually included four texts. In 1978 and 1993 respectively, the National Council of Architectural Registration Boards published Energy Conservation in Existing Buildings and Energy Conscious Architecture both of which discuss the amount of energy consumed by the built environment. The list goes on; however, the upshot is that detailed, quantitative data regarding the extent to which decisions on building and regional planning affect or national energy use have been readily available for many years.
However, we continue to get conflicting messages. On the one hand, we are being told that thinking and acting “green” is essential to global survival and international economic competitiveness. This position is well supported by overwhelming hard information. Yet even when we consider sustainability, we rarely account for the larger scope of the impact.
When we choose to operate an electrical device, we may consider the utility bill that will have to be paid later in the month. We may, in times of stressed utility capacity, realize that this operation may contribute to a system overload resulting in brownouts or blackouts. It is unusual, however, to visualize the contribution that the decision to operate electrical device makes to the plume of smoke and carbon dioxide leaving the stack of a generator three hundred miles away or to the added demand for coal with its related environmental degradation. We don’t think about the part, however small, that our use of electricity plays in the thirty to forty coal mining deaths each year in the United States.
From Greening Modernism, Carl Stein, W.W. Norton, 2010
On the other hand, there are those who inveigh against standards for electric lamps, appliances, showers and toilets, whether or not these standards have any particular impact on our day-to-day experience. Their main thrust seems to be an appeal to the deep “nobody tells me what to do” strain of frontier independence. While this may be fine when we each have miles of empty space around us, it is not viable in the highly interconnected condition that we currently experience. The net effect of this attitude is, in the short term, to compromise our global position and, in the long term, at a minimum to degrade the quality of life for our children and grandchildren and quite possibly to threaten the survival of the planet as we know it.
Dramatic reductions in our energy use are possible through simple, cost-effective substitutions and very modest adjustments in everyday practices. While zero-net-energy and zero-carbon buildings are admirable goals and serve as important test beds for emerging technologies, there should be no confusion about the fact that smart design and careful application of off-the-shelf technologies offer the best near-term methods for reshaping our energy consumption patterns. Not only will these have an immediate impact, they will also inform the attitudes that underlie future design paradigms.
The LA Times article – http://www.latimes.com/business/la-fi-urban-green-20100903,0,588562.story – addressing the intersection of affordable housing and sustainable action raises a number of significant challenges as well as highlighting several relatively successful solutions. Unfortunately, two conclusions, stated or implied, interfere with the simplest, most effective short-term strategies for greening our society.
A primary misconception is the belief that to introduce sustainable measures in low-income communities is problematic because of first cost, and second, that the most effective environmental measures take the form of add-ons such as solar panels. In fact, many environmentally responsible approaches have equal or lower first costs than their less sustainable counterparts, as well as reducing ongoing operating costs. Frequently, the only component that must be added is either clearly presented information, or in the case of new buildings or building retrofit, smart design.
This should not be seen as lowering of expectations or of quality of life, but rather as maximizing the usefulness of all resources utilized. Mt. Airy Woods housing is an example of this strategy. Completed in 1995, the twelve unit (six one-bedroom, three two-bedroom and three three-bedroom) complex had an average construction cost of just over $50,000 per unit which was very competitive with similar projects of the era. However, unlike many low-cost housing projects, Mt. Airy Woods incorporated high-performance windows, significantly higher levels of insulation than required by code, responsive heating controls and zoning, earth-buffering, and low-maintenance materials throughout.
The use of higher quality materials and systems without compromising the budget was made possible by providing the maximum useful living space in the smallest possible package. While the particulars of the Mt. Airy Woods project will not apply to every, or even most projects, understanding their impact is instructive. The site is steeply sloping, having an average pitch of 1:3. In general, this would have been considered a serious drawback to development; however, it allowed the design of multi-unit buildings with on-grade, direct access to every unit. This, in turn, meant that there was no construction for public corridors or stairs. This not only reduced the amount of building which in itself is a significant environmental benefit, but it also reduced the amount of building area that needs to be heated and maintained. Further, it improved accessibility and security as well as giving each unit the sense of “entry” and arrival.
This is a limited explanation of a very specific example but is intended to suggest that the careful application of resources, both those that are purchased and those that pre-exist within the boundaries of a project, can address concerns for sustainability while enhancing quality of life issues, and do so within completely conventional budgets.