< PreviousWRITTEN BY DAVID O’NEILL T hroughout modern history, construction has been constantly advancing. The precision and expertise avail- able to the builders of today is incomparable to the structures of previous generations. While that isn’t to suggest that historical buildings are poorly designed or built - the Pyramids of Giza being a prime exam- ple of the skill that humans have always possessed, things have certainly moved forward. These changes and developments are unquestionably linked to the generations they were introduced by. The reasons for their intro- ductions, however, are not as straight forward. Available materials and innovation in building techniques have all contributed towards the advancement of the industry but equally, style and architectural trends have been factors. Gone are the superstructures of previous generations where concrete and metal were the dominant ingredients. | 30 AUGUST 2023| 31 APEIRON CONSTRUCTIONThey have been replaced by large scale glass structures which are, for many, more aesthetically pleasing. Additionally, and not an insignificant detail for those tasked with produc- ing these structures, glass is both cheaper to build and more environmentally conscious. With these trends in mind, it is no surprise that glass is being utilized increasingly in the con- struction industry. As the focus has turned to environmental concerns —amongst a growing concern about the construc- tion industry’s own contributions to emissions targets— there has been an increasingly loud call for sustainable materials. Emissions heavy materials are being substituted and the built environment has had to adapt once again. The relationship between glass and the construction industry goes back centuries, at least. Through the process of glass blowing, established in the 1st Century, the material was used in vases and tiles. It was very quickly sequestered into every- day building with windows of glass being found in Ancient Rome. In 1958 however, things changed massively. Through the sophisticated float glass process, the material could be produced free of distortion and in a variety of thickness. Over- night, glass changed from being a decorative yet brittle mate- rial used to cover wall openings, to the wall material itself. Its popularity in building exteriors skyrocketed and it is now synonymous with cityscapes. However, according to recent scientific developments, its full potential in the construction industry may still be ahead. According to Mithila Achintha, researcher at the University of Manchester, UK, the sustainable benefits of glass are many and its unique qualities make it an ideal choice when it comes to construction. “Many qualities make glass attractive, as it is transparent, chemically inert, environmentally friendly, sus- tainable, strong, easily available and relatively cheap.” Despite this, it seems as though there is even more that it can offer. Reactive glass, the ability for glass to change according to its environment, is nothing new. People have carried it in the lenses of their glasses for many years. The ability to respond to natural light and darken when it in direct sunlight is a neat, yet reasonably normal trick. However, the science behind these glasses is considerably more interesting, and the potential for truly transformative products may be upon us. The glass itself is in fact coated in a thermochromic material. When in contact with sunlight, its molecules are rearranged to darken the glass and block glare. While that particular solution is yet to be discovered, other sig- nificant developments have already taken place. Researchers at the National Renewable Energy Laboratory have success- fully managed to great window applications that tint in the sunlight while also generating electricity. According to Lance Wheeler, scientist at NREL and co-author of the study, the perception of solar power is a misguided one, at best. “There are preconceived notions of what an energy-efficient building looks like, and it usually is not highly glazed, and it probably isn’t very tall. We found that there are other ways to build high-efficiency buildings.” The need to identify solution to high- ly-glazed buildings is a simple on. In cities across North Amer- ica, structures with a higher ratio of window to wall required significantly more energy to cool the rooms inside. Simply put, the larger the windows, the more energy it expended. The NREL asked the question, how can we turn this problem into a potential solution? The answer was PV Glazing, an innovative technology that harnesses thermochromic mate- rials and transforms windows into electricity generators. By placing a film of a solar-cell called perovskites over the glass, the window reacts in fascinating ways. What’s more is that, when PV glazing was installed the ratio of window to energy usage was directly inverted. Wheeler went on to explain that, while PV windows may not be the answer long-term, the potential for energy generation in high-rise and large scale building work is phenomenal. “I don't want to sit here and say we should be building highly glazed buildings. We should be “By incorporating these technologies in high-rise buildings, skyscrapers can take a significant step towards becoming net-zero.” | 32 AUGUST 2023building highly efficient buildings. But if we if we choose to keep making these buildings, we’ve got to reconcile their lower performance somehow, and PV windows are one way to do that.” Furthermore, according to Wheeler and his colleagues, the research demonstrates how significant a breakthrough this is in terms of further use of perovskites and energy con- sumption. “The work demonstrates the extraordinary prom- ise of perovskites to reduce building energy consumption and mitigate climate change without sacrificing the architec- tural freedom of glazing.” He believes that, by incorporating these technologies in high-rise buildings, skyscrapers can take a significant step towards becoming net-zero. “Picture a skyline in, like, New York City where there are these high- rise buildings that are entirely glass. They're fully glazed. The Freedom Tower has millions of square feet of glass. It could be a power plant in itself.” While this is a hugely exciting and transformative break- through. The need to counterbalance the energy consump- tion has its negatives. For a start, it is an reactive, rather than proactive. So, how could these technologies be advanced further to take a forward step in the battle to reduce energy consumption. The potential answer is a Smart Window. Research is currently underway to find materials that block both light, and heat, which would have a considerable impact on the heating and cooling of buildings. Rather than generate power to offset a structures energy consumption, scientists are aiming to produce materials that react to light and heat by adjusting to reflect heat, thereby turning skyscrapers into enormous passive houses. According to a recent study that looked into the viability of such technology, a high-tech design using nano-wires successfully combined electro- and thermochromics for Smart Windows. “These smart windows, which have a wide response range of 30–50 °C, can dynam- ically adjust their blocking performance. As the ambient temperature increases, the window’s ability to block sunlight becomes stronger. The wide response range allows smart windows to progressively adjust their blocking ability as the temperature changes, dynamically regulating the room tem- perature in various real-world weather conditions.” While this particular study is still at an early stage, there is a clear indication that the relationship between glass and energy saving has a long way to run. As history has shown, design can change due to any number of factors. It seems that, as glass becomes the ubiquitous choice in high-rise building, the combination of style and innovation is one that may stay in fashion for a long time to come. go.nature.com/3DULEup bit.ly/3OATWgN | 33 APEIRON CONSTRUCTIONWRITTEN BY LUKE SHEEHAN I n an industry doing its level best to reduce its carbon emissions, alongside omnipresent labor shortages and an aging infrastructure that requires upgrading, it is safe to say that those within the construction world are under considerable pressure. While this is true right across North America, the landscape is particularly challenging in Florida. Major pub- lic works projects, coupled with the pressures of a tough sea-facing and hurricane-prone environment, means that those within the industry are certainly kept occupied. It is not just weather-related challenges that companies are up against, either. The state has a well- earned reputation for technological advances and innovation, with 2023 marking the 27th year of the Florida High Tech Corridor. Impressively, the area counts 20,000 tech companies and rivals both Silicon Valley and North Carolina’s Research Triangle. All of this serves to illustrate the pressing need for Florida’s construction industry to maintain its high standards, continue its growth and most of all, stay ahead of the curve. No doubt about it, Florida’s builders are busy. It is within this context that the precast, prestressed concrete producers sit, a growing sector with massive potential and strengths across multiple platforms. | 34 AUGUST 2023| 35 APEIRON CONSTRUCTIONGiven its relatively recent use as a construction material, the precast, prestressed concrete community is a close-knit one. Consisting of multiple producers that cover specific market segments such as transportation, commercial, municipality, and architectural projects, it also has a strong tendency towards specialization. With this in mind, it is no surprise that for those within the sector, strong representation is essential. The Florida Prestressed Concrete Association (FPCA) was founded in 1957 and came about through a need to advance the knowledge and application of a material that was, at the time, both revolutionary and in its infancy. As the first pre- cast concrete association in the nation, and the driving force behind the foundation of the Precast/Prestressed Concrete Institute (PCI), it has amassed a wealth of experience and knowledge that continues to accelerate the construction industry. Unsurprisingly for an association with such a back- story, its primary goal, “to provide the construction industry in Florida a superior building system that is durable, attractive, and economical,” has never changed. Diep Tu, P.E., has been Executive Director of FPCA for six years and, while the association has always maintained an upward trajectory, it is certainly now benefitting from his astute leader- ship. Now crafting a career in one of the most important states for construction in the U.S., Tu had previously worked a great many stations, contributing in depth to sectors as diverse as government, private enterprise, and educational outreach. After graduating from the University of Florida, he worked for the Department of Transportation as a Concrete Research Engineer before moving on to the role of Director of Engineer- ing at the Florida Concrete & Product Association, which ulti- mately lead him to his role at the FPCA. As Tu explains, as the Executive Director of a state association and a chapter of PCI, he works alongside colleagues and experts from across the industry, with representatives such as producers, vendors, and professionals who all work collaboratively towards the same goal: increased industry presence. While the current outlook is not without its challenges, those at the FPCA believe that the outlook is a positive one. For Tu, the role of the Association does not deviate and regardless of the vagrancies of the industry, it is committed to facilitat- ing, educating and communicating. He states that building ‘networks of knowledge’ and creating clear pathways for new entrants to the industry is the association’s priority. As he explains, ensuring a source of labor, in the midst of a skilled worker shortage, is no easy task. It involves a hybrid of B2B marketing and education. “When talking to professional practitioners, you are educating them on your industry and resources from the get-go; when you go to schools with your know-how, you educate the next generation.” In order to promote the industry and encourage potential new entrants, this education needs to happen early. With indus- tries all competing for the highest quality workers, the FPCA knows that it needs to act decisively. The association leads outreach programs to various educational settings such as universities, colleges, vocational, technical, and high schools. Encouraging industry engagement, FPCA offers scholarships that are tied to internships and provide financial support, equipping students with the opportunity to work with mem- ber producers. While Tu accepts that this does not provide any guarantees, it may end up being a motivating factor to inspire the next generation to join the precast, prestressed concrete industry. However, he is progressive in his assess- ment because ultimately, he believes that it will benefit the industry in some form. “If they happen to become designers, architects, researchers, vendors, planners or anything else adjacent to the industry, they will still be familiar with our products, and how our processes take place.” Another element that Tu and the FPCA identify as crucial to safeguarding the future of the industry is positive and effec- tive connection. As Tu explains, communication is key. It is at the heart of the work being carried out by the association and can be seen in the interactions that take place between different generations of workers, and the distinct profes- sional roles that the association’s members serve. By way of example, he explains how the association’s twice-yearly conference invites vendors and industry experts to share innovative new materials and products such as automation, robotics and 3D printing. These gatherings provide members with the opportunity to meet up with producers, visits educa- tional institutions, and learn about exciting new technologies from the experts. For Tu, the developments are ushering in an exciting new era for the sector. “One might spend months building a wooden form. Contrast that with the process of 3D | 36 AUGUST 2023printing a mold, which could be completed in just a couple of weeks. This means we can produce quality products for our clients faster and more cost-effectively.” Overall, however, communication is a balance. As Tu emphasizes, it is important to address both the personal and the collective. The FPCA regularly shares insights on the industry along with developments, news, research, and high-profile projects in its newsletter. By maintaining a vocal presence, the association ensures the industry at large remains educated on all things FPCA. Tu furthers this education drive by attending local conferences such as the American Institute of Architects (AIA) and the American Society of Civil Engineers (ASCE), where he exhibits and speaks to large audiences of architects and engineers, highlighting the benefits of prestressed concrete and the effectiveness of the association’s members. While the growth of prestressed concrete across the industry is undeniable, challenges persist. One in particular is the reg- ulatory and administrative impact of Environmental Product Declarations (EPDs) on the industry. Tu states that while their implementation is a near-future priority, they can be seen as a powerful data collection tool. “I know that local municipalities and local governments are pushing for more EPDs around the country. We also need to be aware of what is coming over the next 5 to 10 years. EPDs require a lot of data collection, and the more data you collect, the better your insight into trends, into how your products are developing, and how to prepare to exceed the standards.” Through continuous contact and work with the PCI, a substantial amount of information on EPDs has already been collected. Unsurprisingly however, he believes that collective communication is vital in this instance and believes that the question should be best viewed from a national standpoint. Eventually, Tu says, every chapter will be required to use the same format and when these standards and formats are settled, his members will have the clarity to catalogue the materials they are using. For now, he says, it is a time for learning. “Awareness efforts are ongoing. This summer, I have speakers that will come in and talk about EPDs which will give our producers a glimpse of what they are and what to expect.” The Florida Prestressed Concrete Association is the longest running association in its sector. It has provided support and advocacy to its members for decades and has endured industry change, adaptations, and innovation alongside a backdrop of encroaching everglades, floods, and hurricanes. For Tu, one word describes the experience of his industry, the association, and its members: resilience. With this, in addition to strong communication and effective education, the industry looks to be in very safe hands for many years to come. “We can build structures on elevated foundations, and on pilings. We make precast sea walls. Naturally, precast, pre- stressed concrete products are inherently stronger, because of all the high-strength materials and reinforcements that come into play. Precast, prestressed concrete products pro- tect lives because of they are long-lasting and durable.” “By maintaining a vocal presence, the association ensures the industry at large remains educated on all things FPCA.” | 37 APEIRON CONSTRUCTIONfor the process of creating precast concrete paneled buildings was first awarded in 1950—it has increased in reputation and demand in recent years. While the process and product may seem restrictive, being made in a modular fashion, the reality is that precast concrete lends itself to a wide range of creative and innovative applications. Florida-based Leesburg Concrete Company, a PCI-certified precast and architectural concrete producer, is one such company that pushes the boundaries in both regards to excellent effect. In addition to architectural precast concrete cladding, the company produces stairs, wheelchair ramps, loading dock ramps and steps for clients. What sets the company apart from its competitors, however, is that Leesburg also works on custom precast concrete buildings which are designed and produced to client’s individual needs. Founded in 1983, Leesburg Concrete Company recently celebrated its 40th anniversary. For Kirk Rouse, Pres- ident, it is a significant milestone and a testament to the company’s hard work and innovation. “We have had a unique history, growing organically over the past 40 years after starting out as a small block company that produced only split-faced blocks.” These humble beginnings soon grew into a rich and varied product line such as the production of precast concrete steps. However, it was the enforcement of the Americans with Disabilities Act in the late 80s that saw the company take off. In the first of its many feats of innovation and creativity, Leesburg developed a modular code-compliant wheelchair ramp made with precast concrete. As Rouse explains, by also manufacturing the railings for these ramps, the company can be a one-stop-shop for clients. “By making the accompanying railings, we provided a pre-engineered, code-compliant wheelchair ramp that would be delivered and installed on various buildings where access was needed, per the building code.” WRITTEN BY EMMA KILCAWLEY HEMANI T he precast concrete sector is one of the fastest growing areas of the construction industry in North America. While a relatively new product – a patent | 38 AUGUST 2023| 39 APEIRON CONSTRUCTIONNext >