Prof. Hernández Remero
November 30, 2017
Alternative Architecture: Steel and Concrete, Solutions of the Future
Commercial construction and homebuilding consume nearly fifty percent of the total lumber produced yearly. This year, ninety-five percent of single-family houses built in the United States today are composed of wood framing. David Johnston and Scott Gibson state in their article, “Home Power”, that “Wood holds a low embodied energy, natural durability, high strength, and low natural toxicity” (Johnston and Gibson). These qualities make wood one of the most acceptable and best-suited renewable materials for conventional construction.
However, homes these days, are more often than not, over framed. Joists and beams used to create vertical and horizontal supports are oversized, and studs are tripled up at corners. The misuse of wood is explained by the imposition of strict structural codes implemented by individual city building ordinances that require architects and designers to follow guidelines, as opposed to calculate specific beam and column sizes according to their load that is applied to them. Minimal use of prefabricated systems is implemented, causing an increase in the number of materials used and needed for the structure. Prefabrication is a method in which sections of the structure are conceptualized through panels. These panels are assembled in a factory, then transported to the site and fastened together, in conclusion, minimizing waste and overall materials. Although wood is a renewable resource, it is not sustainable because we are consuming it faster than it is produced and human-made materials such as steel and concrete are therefore better choices.
With wood construction being a significant contributor to the consumption of wood and thus keeping the demand for wood emphasized. Loss of forest quality has already occurred in the majority of Europe, North America, and Australia. As those forest banks continue to deplete, commercial foresters began to move into several Southern countries. According to a study done by National Geographic, Forests currently cover close to thirty percent of earths landmass, with fifty percent of the world’s tropical forests having already been cleared. Carbon dioxide emissions are at an historical high and forest loss contributes nearly 12 percent to that annually (Wallace, 4). There will never be a change in the direction of destruction unless the ideologies behind conventional construction methods change.
Architects, designers, and contractors need to consider a smart and sustainable alternative to wood. Currently, about eighty-seven percent of the country’s multifamily construction uses wood framing. In 2015, according to the U.S. Census Bureau, "Builders used steel framing, wood's closest competitor, about four percent of the time, with concrete, insulated concrete forms and other framing methods making up the balance. Therefore, when the city council in Sandy Springs, GA, decided to ban wood construction more than three stories high and larger than 100,000 square feet as of August 16, 2016, that curveball took the industry by surprise, particularly since there has been an uptick in high-rise planning using all wood." (Slowey). Proving that this ideology of material transition has not only been developed and theorize, but also has been implemented and enforced. Now it must just be refined, the new regulation implemented by Sandy Springs in reality only restricts commercial building since there is a minimal amount of homes being build that is upwards of one-hundred thousand square feet.
Currently, deforestation is the most significant problem with the impact that wood has on our natural environment. Deforestation is a plague that threatens half of the most important sites for plant diversity. A Thousand acres of forest and woodland are cleared or degraded each week by commercial loggers (Blahnik). About this theory, The RIC Good Wood Guide explains, “For many years, the timber trade has claimed that it plays a negligible role in forest loss and that most deforestation is caused by agricultural clearance or fuelwood collection.” Population growth, rather than industrial exploitation has been blamed as the underlying problem. Research by WWF leads us to the opposite conclusion. Taking the survival of biodiversity as a major criterion, WWF concludes that the timber trade is currently the most important cause of loss and forest degradation in the world (World Wildlife Foundation).
As a side effect of this deforestation, a dramatic decrease in tree species and other adverse impacts are occurring in parallel. The practice of “slash and burn” is widely practiced and not just within the lumber industry, but also agricultural farmers. This method usually involves clearing acreages of tree and forestry and burning them (see figure 1).
Figure 1 - Deforestation by World Wildlife Foundation
Not only contributing to an enormous amount of wasted resources but also destroying the inhabitance of the living ecosystem that this once standing forest supported. Scott Wallace, an author from National Geographic, and writer of “Deforestation” said in his article, “Forest cover about thirty percent of the planet, but deforestation is clearing these essential habitats on a massive scale. Often resulting in damage to the quality of the land. The world’s rainforest could completely vanish in a hundred years at the current rate of deforestation” (Wallace, 2)
Once the plot of land is cleared, the farmers will only plant-specific tree species that are profitable or hold importance to their business (see figure 2). Often rotating plots of cleared land as the fertility of the previous plot is decreased. This method, though viewed as a sustainable act, causes more harm to the native environment. When planting foreign or intrusive tree species into a habitat that they are not native too, can create stress on the environment and these new trees will battle with the indigenous habitats often further destroying or killing native plant species. There is also documentation that once trees began to pollinate, controlling the rate and magnitude of the spread is extremely difficult.
Figure 2 - Tree Farm by Unknown Photographer
In a study completed by the National Park Service of Pacific West Region and reinforced by sustainability advocate, Tara Wagner concluded that, "One of the common concerns in using a conventional wood sealant is the impact any potential arsenic in the product has on our health. According to the World Health Organization, arsenic can cause vomiting, abdominal/digestive issues, numbness or tingling, muscle cramps, skin lesions, skin cancer, lung and bladder cancer, and more. Another common ingredient is petroleum distillates, linked to everything from respiratory issues to liver and kidney dysfunction." (Wagner) Though, advancements have been made in creating eco-friendly and sustainable methods of wood sealant, varying in types of wax and oils. It has been found that these methods result in some reapplications or constant threats of mold and complete failure of the methods. A study by "Sustainable Baby Steps" was also completed testing the characteristics of the leading natural wood sealer companies as a means of prioritizing aspects of what makes it ‘sustainable.' The priorities and outcomes where listed as follows,
- How eco-friendly is?
- How was the coverage?
- Does it contain an odor?
- Does it perform as expected?
- Does it hold up to the elements and how often do reapplication need to occur
- How does it look?
The first company tested was ECOS WoodShield, which is a water-based very low odor, and zero VOC finish. "The WoodShield left a hard, moderately shiny finish, and we found it to have good water resistance," this product tested was the eco-friendliest. Followed by SafeCoat Acrylacq, this company is both SCS and LEED Certified, water-based, low-VOC and non-toxic. SCS is a trusted leader in third-party environmental and sustainability quality verification, and LEED (Leadership in Energy and Environmental Design) is most widely used green building rating system in the world. LEED certification is a globally recognized symbol of sustainability achievement. "SafeCoat Acrylacq, had quality water resistance with a slightly cloudy appearance to the final product, especially if moisture is present in the application. EarthSafe was also tested, a natural wood stain and sealer in one. "It is also water-based and non-toxic with zero VOC but did have a strong odor (Wagner). As I read on, most of all the ‘natural' wood sealers reacted with consistent outcomes. However, they all require an annual reapplication period as opposed to the five to six-year period of the more toxic competitors.
While there are already alternative materials that can compete with wood, like steel and concrete, it raises questions as to why these materials aren’t being the preferred materials for construction? Steel, more specifically, light frame steel, has been proven for its durability and longevity. Steel has an incredible strength-to-weight ratio. Steel studs weight one-third less than wood studs, making them easier to handle and due to their structural strength, they can be installed at twenty-four inches on center instead of the typical sixteen inches (see figure 3). Also with any construction project no matter the size, labor costs are in fact typically the most significant expense. With steel frames and panels, labors hours can be minimized. Wood framed construction requires skilled laborers who must spend countless hours measuring, cutting, and drilling lumber before erection can even take place. Steel framing can be down with relatively untrained workers and completed much faster due to prefabricated members from manufacturers.
Figure 3 - Steel Framing by Ace's Builders
Steel also allow extreme flexibility within a design, opening new doors of ingenuity and creating programs to change with time. A Professor and Graduate student in the Department of Technology at the University of Maryland said in his writing, “…Sustainability in Modular Construction”, Prefabricated construction is steadily replacing traditional construction due to benefits and reduction of cost. With prefabrication, there is a guarantee of speed, quality control, and a safer environment overall. However, the method of prefabrication requires skilled labor, but this shortcoming is out weight by the long list of provided benefits (Molavi).
Steel also does not crack, warp, expand, or contract due to environmental attributes, further contributing to the longevity of the aesthetic material, further cutting down cost and maintenance. For example, when wood warps or cracks, the finishing material mimics its base, cracking or warping with the wood studs requiring extensive repair to every layer of the building (see figure 4). Steel framing members are also extremely reliable and have been proven to withstand extreme natural disasters such as earthquakes and hurricanes. That is why conventional structures erected with steel are used as evacuation centers such as schools, churches, and other municipal buildings. Like other industrial activities, steel construction has become a direct correlation on several essential sustainability issues, like energy and waste, and what further innovation can be done. Improvements in sustainability can be found through every stage of construction, but the most detrimental is located in the beginning stages.
Figure 4 - Warped Vinyl by Business Builders
Other countries have also pushed for limiting the use of lumber framing, switching to light steel frames as they become more aware of the negative impacts of wood and understanding there are smarter and more sustainable alternatives. Using steel allows precise design and manufacturing process ensures waste is kept to a minimum during manufacture and installation. Another positive attribute is that steel is one-hundred percent recyclable reducing end product waste and excessive scrap material. As a leader in steel framing based in Australia since 1960, Dynamic Steel Frame explained, "When it comes to steel framing systems, a lot of homeowners think steel framing is a relatively new phenomenon in modern housing construction. However, steel has been used as a building material in Australia for over 50 years and continues to grow. Steel has been experiencing a boom in recent years thanks to the many advantages it offers homer owners and builders.”
This also raises the question of why steel isn’t used more often? Maybe, it is due to more specific critical issues from the manufacturing end of how light steel framing members are produced. Does it cause an abundance of emission in production to emit them into the indoor environment? It is essential to know what the meaning of emissions are and how it affects our environment, thus creating a significant impact on the organic matter. According to Sustainability of Steel-Framed Building, “What is important to material manufacturing industries is implication that emissions have to air and water, and mainly originate from the upstream processes and transports including combustion of organic matter. Examples are processes for material production, heating, and conversion to usable energy, and also read and sea transports. Main airborne emissions are carbon dioxide, nitric oxide, sulfur oxide and dust” (Sustainability of Steel Framed Building). According to the research, the total emissions produced by other building systems within the same function a size is relatively small compared to steel. Furthermore, comprehensive studies completed show that steel and different significant steel construction-related materials are fully recyclable (see figure 5), will not release any emissions in the future and are not combustible or create deposits from deterioration.
Figure 5 - Steel Recycling by Waste Managment North West
After realizing the improvement opportunities presented through light steel framing and the possible impacts of its production, I began to research how the indoor environment and the elements of the built environment affect us. As the International Iron and Steel Institute of Belgium explains, people of modern society have become accustomed to spending more than ninety percent of their lives occupying an indoor environment. Creating an important and complex relationship between indoor environment and human health. The main issues that have become prominent are moisture, thermal comfort, sound, and air quality. (ISIAQ-CIB Task Group, 3). More importantly, the impacts that hygroscopic materials have on our health is a substantial amount. For example, wood is a hygroscopic substance as it readily attracts and absorbs water from its surroundings. Due to the affinity that our atmosphere contains an abundance of moisture, hygroscopic materials require means of sealing out these compounds of humidity, or it can lead to detrimental effects.
Though wood continues to have the most significant advantage over the construction industry as it is the material builders and tradespeople are the most familiar with, concrete is the world’s leading most-used building material, but it is because of the use is primarily based on the need for foundations. Building Your House, Yourself University (BYHYU), an independent company that strategizes successful mean of building explained, "Only five and a half percent of US homes are built with concrete masonry units (CMUs), and less than 1% are built with Insulated concrete forms (ICFs). Concrete homes are usually constructed with concrete foundations and concrete exteriors walls, the remaining structure composed of wood.” However, if this the exterior treatment and the attempt of the interior structure began to incorporate the use of concrete more prominently, it would cut the use of timber within construction by more than fifty percent. As I analyze the characteristics of concrete and the means of sustainability. Concrete holds an array of positive attributes that can mimic or exceed that of wood. Concrete's primary qualities are its performance in active using energy, its economic and structurally sound aspects, and the sustainable nature.
Through advancements and innovations in building techniques and materials, concrete has begun to outperform wood as a material in construction, no longer creating a need for constant repair and costs in maintenance. Both resilient and versatile, concrete is an incredibly sustainable and cost-effective alternative to wood for both residential and commercial buildings. Concrete is a composite building material that consists a coarse aggregated material bonded together with liquid cement that cures over time. The majority of concretes are lime-based, such as Portland. Portland cement, is the basic ingredient of concrete, mortar, and many plasters (see figure 6). The earliest documented application of cement was thousands of years ago. Where concrete-like materials were used since 6500 BC, then further developed by Ancient Egypt (The History of Concrete). What can be taken from the history of concrete is the simplicity of its creation and how the primary methods of development have remained true to their roots. That concrete is a simple mixture of clay, limestone, water, gravel, and sand, which as a terrestrial planet we have an unfathomable amount of these resources.
Figure 6 - Photo by http://ieltsliz.com/ielts-diagram-model-answer-score-9/
Compared to both light steel framing and traditional wood framing, concrete is the most durable, and unlike the two, concrete gains strength over time. As a leader in concrete production and research, Concrete Sask explains that “Concrete’s one-hundred-year service life conserves resources by reducing the need for reconstruction. Concrete has immense resists to weathering, erosion and natural disasters need few repairs and little maintenance.” Thus, adding to the conservative values as well. A sustainable concrete building that manages to stand for the estimated one-hundred-year lifecycle can save more than twenty percent of the total initial construction cost.
Much of these savings come from the direct effect of concretes natural abilities of thermal mass. You need a word or phrase before all quotes "Thermal mass is the ability of material to absorb and store heat energy. A lot of heat energy is required to change the temperature of high-density materials like concrete, bricks, and tiles. Lightweight materials such as timber have low thermal mass." (Sustainability Workshop, by Autodesk.) Concrete is even sensitive enough to capture the energy produced by lighting fixtures and other equipment in the building, this all allows a structure to remain cool during the day and warm during the night (see figure 7). The safety presented by concrete is also extremely trustworthy. As a building material, it is both secure and healthy for builders and the occupants. This is because concrete is a chemically static material, meaning that it cannot burn, rot, or create any means of "off-gas." Off-gas is the process in which a material begins to release any volatile organic or inorganic compounds, providing excellent indoor air quality. (Concrete Sask; Resources Page, web). Also opposed to light steel framing, concrete has been around for centuries, meaning the techniques in which the systems of construction are developed have become refined and are well understood by most builders due to the need of foundations within a prominent portion of construction projects.
Figure 7 - Photo by GreenSpec
As conventional wood framing has become more and more prominent in methods of building, it has taken place as the building material attached to the muscle memory of construction. That wood has become second nature to builders and little to no thought is being put into how it affects the world we live in and how logical and feasible alternatives are genuinely present and should be implemented regardless on the application of construction. That if the thought of sustainability and the ability to remain environmentally-conscious throughout the development of design and construction with the means of leaving the smallest environmental footprint possible. It would not only improve the longevity of these developments, creating buildings with meaning and purpose. But also reduce waste and byproducts resulting from this overconsumption of materials. The wood itself is an extremely trustworthy and reliable technology regarding sustainability, but we cannot allow that idea to become the master of our world. Instead, allow it to become a stepping stone in which we grow, we cannot lose the spark of innovation that has brought civilization so far because we believe we have found something that can adhere to our every need. "Resilience is all about being able to overcome the unexpected. Sustainability is about survival. The goal of resilience is to thrive” (Jamais Cascio). Society must realize the scale of impact that the built environment has on our ecosystem, and then become aware of what it means to be sustainable. This ideology will not only produce a better future for humanity to grow. But, civilization will respond cohesively by instead of praising the ideology of sustainability, allow it to become the standardization of building and development. Creating the means that sustainability is no longer an achievement praised for its ingenuity, but an afterthought of design and construction. That the idea of sustainability is changed from a conscious proposition, into a subconscious mechanism. That the only way to create a better future is to start today.
Bradford, Alina. “Deforestation: Facts, Causes, and Effects.” Live Science Contributor. 4 Mar 2017 Web. Accessed 26 November 2017. https://www.livescience.com/27692-deforestation.html
Malesza, Jaroslaw & Miedzialowski, Czeslaw. “Current Direction in Development of Modern Wood-framed Houses.” Bialystok University of Technology. MBMST 2016. Scholarly Article. 21 February 2017.
NAHB – National Association of Home Builders Research Center. Advanced Panelized
Construction. Year One Progress Report, prepared for Partnership for Advancing Technologies in Housing (PATH), Washing D.C., US. 2002.
Multiple Authors. “Performance Criteria of Building for Health and Comfort.” Publisher
Unknown. The International Council for Research and Innovation in Building and Construction (CIB). Task Group 42. Standards & Guidelines. 2004.
Blahnik, Tate. “Deforestation and the Lumber Industry.” Stanford Edu. Web. Accessed 19 Nov.2017. https://web.stanford.edu/class/e297c/trade_environment/children/hindustry.html
NAHB Research Center Inc. “Alternative Framing Materials in Residential Construction: Three Case Studies.” U.S Department of Housing and Urban Development. April 1993. Web. 15 Oct. 2017. https://www.huduser.gov/portal/publications/destech/altframe.html
World Wide Fund for Nature (WWF). "The RIC Good Wood Guide." Web. Accessed 18 Oct. 2017. http://www.rainforestinfo.org.au/good_wood/log_maj.htm
Woolley, Tom. “Building Materials, Health and Indoor Air Quality: No Breathing Space?” Taylor & Francis, 2016. Print. ISBN – 131738976X
Multiple Authors. “Build Your House Yourself.” Online Publication. Accessed 5 Sep. 2017 http://www.byhyu.com/home--podcast/are-you-sure-that-wood-stick-built-construction-is-the-best-choice-for-your-new-home-byhyu-038.
Multiple Authors. “The History of Concrete.” Dept. of Materials Science and Engineering, University of Illinois, Urbana-Champaign. 8 Jan. 2013.
Tuan, Christopher Y. & Yehia, Sherif. “ Evaluation of Electrically Conductive Concrete Containing Carbon Products for Deicing.” ACI Materials Journal. May 2013. Print.
Molavi, Jeffrey & Barral, Drew L. “A Construction Procurement Method to Achieve
Sustainability in Modular Construction”. Elsevier Publishers Ltd. Article. 20 May 2016.
Gissen, David. "Subnature: Architecture's Other Environments." Princeton Architectural Press. 01 November 2005. Print.
David Gissen is a Professor at the California College of the Arts, a visiting professor at the Massachusetts Institute of Technology, History Theory Criticism program and Columbia University's Graduate School of Architecture. Presented numerous lectures schools in the United States and Europe and teaches in areas of architecture, urban, and landscapes. Gissen is the author of books, essays, exhibitions and experimental writings and projects about environments, landscapes, cities, and buildings from our time and the historical past. In addition to these texts, David is also the editor of several book-length works including the "Territory" issue of AD (Architecture Design) Magazine. "Subnature Architectural Environments" is a paper bound, soft cover book. Published by Yale Publishing Company and proves to be useful to scholars, educators and working professionally in an array of fields. What about the currency of work? It proved helpful information directed to sustainable alternatives for both construction methods and design materials. This book emphasizes many flaws and draws backs to traditional methods of construction, making this text paramount to the topic of discussion. It not only critiques conventional means of building but justifies these ideas by giving logical and feasible alternatives.
Wallace, Scott. “Deforestation, Last of the Amazon; National Geographic." National Geographic Partners, LLC. National Geographic Society. January 2017. Magazine, Volume Last of the Amazon.
Scott Wallace is an award-winning writer, photographer, broadcast journalist and public speaker who covers the environment, vanishing cultures, and conflict over land and resources in the world’s volatile frontier regions. He is a former Central America Correspondent for CBS News, Newsweek, and the Guardian. Scott Wallace graduated from Yale University with a degree in philosophy and a degree in Journalism and Broadcast Reporting. His works are constructed with an emphasis on international politics and the exploit of natural resources creating a stable audience of scholars, educators, activists, and environmental industries. This particular article was published in 2007 in a volume of National Geographic Magazine. I used an article that he wrote called "Last of the Amazon" that was published in a volume of National Geographic, which a golden star magazine and internationally publicized magazine that hold countless awards and supported by numerous reputable authors and photographers. This article in particular touched base on a major issue covered in my paper, the impact of deforestation and the implications it holds for the future if we continue down this path. Creates a foundation of my argument to why alternatives need to be found and materialized quickly.
Slowey, Kim. “Wood Construction: How does it stack up?”. Construction Dive. National
Geographic Society. January 2017. Magazine, Volume Last of the Amazon.
Kim Slowey is a writer who has been active in the construction industry for the last 25 years and is licensed as a certified general contractor in Florida. She received her BA in Mass Communications/Journalism from the University of South Florida and had experience in both commercial and residential construction. She is currently a writer and editor for Industrydive.com. A company that analyzes and publish in-depth feature articles. Prioritizing how designers and developers build intuitive products that are device agnostic. Making business news easy to read, meaningful, and fun. This is an online article from their website on the sustainable alternative of steel framing. Currency? This precisely reflects on the topics that are represented within this paper. Becoming an extremely useful and professional precedence for information and data to be referenced. Mainly used for reading and creating an understanding of the sustainability attributes of steel compared to wood.
Multiple Authors. "Sustainability of Steel Framed Building." Stalby Gnads Institute. Source Files, Website <http://www.stalbyggnadsinstitutet.se/uploads/source/files/Artiklar/SBI- Sustainability_of_steel_framed_buildings.pdf>
This is an embodiment of sustainability information and understanding condensed into criteria. More precisely this educational reference document is a summary of the principals of sustainability criteria for construction and demonstrated the sustainability of steel construction concerning some vital environmental issues in the world more prominently in the America and Europe. This document is a paper reference tool with an enormous amount of information on steel sustainability. Currency? I acquired a PDF format from the internet, and I was instrumental. This document would primarily target an audience of working professionals in the construction industry, students, and scholars that emphasize a study in construction methods or architecture and development. It can also be used to understand both the economic and ecological impacts of building materials. I, in particular, found this reference document extremely useful pertaining this specific essay as it not only gives valuable information about steel construction sustainability, and sustainable design. But also, the recycling and reuse of steel materials. Emission production of the creation of theses steel members and critical issues of steel construction like operational energy, waste and land-use and the impacts of the indoor environment.
Figure 1: Unknown Photographer. "Deforestation". World Wild Life Foundation. April 21, 2017. https://www.worldwildlife.org/threats/deforestation
Figure 2: Hearn, Bradley. "Tree Farm". https://www.reddit.com/r/oddlysatisfying/comments/2wwca3/tree_farm/?st=jan86nje&sh=5b4dcf2a
Figure 3: Unknown Photographer. "Steel Frame House." Scottdale Construction System Ltd. http://www.scottsdalesteelframes.com/gallery/residential/steel-frame-house-ankara-turkey-1/
Figure 4: Unkown Photographer. "Warped Vinyl." High Mark Exteriors. http://www.highmark-exteriors.com/siding/the-most-common-vinyl-siding-problems.html
Figure 5: Waste Management. "Recycling of Steel". http://wmnorthwest.com/educational/steel.htm
Figure 6: IELTS, Liz. "Cement/Concrete Production". February 25, 2015. http://ieltsliz.com/ielts-diagram-model-answer-score-9/
Figure 7: Green Spec. "Thermal Cooling/Heating." http://www.greenspec.co.uk/building-design/thermal-mass/