Global collaboration is the cornerstone of scientific advancement. Frontiers in Built Environment has organized a series of special edition Research Topics, with the goal of highlighting the latest advancements in Sustainable Design and Construction across the globe, showcasing the academic excellence and high-quality work of internationally recognized researchers. These collections aim to shed light on the recent progress made across the entire breadth of the Sustainable Design and Construction field, and reflect on the future challenges faced by researchers across borders. Please note, contributions to the collection are by invitation only.

University of Coimbra

Polytechnic University of Milan

The Cyprus Institute

Insight into emerging trends in Sustainable Design and Construction across Europe

. The research topic of this collection of scientific articles is the use of new technologies in the construction sector to reduce energy consumption, improve sustainability, and provide resilient structures in extreme environments. <ul> <li>Extreme weather conditions can be mitigated through the use of bio-enhanced self-repair materials and microbial enhanced carbon-fixing limewash.</li> <li>Life cycle energy analysis (LCEA) is a tool used to assess the energy consumption of buildings, and timber framed constructions have lower embodied energy than concrete and steel buildings.</li> <li>Mycelium-based composites offer an alternative, biological approach for constructing regenerative and adaptive buildings in extreme environments and extraterrestrial habitats.</li> <li>Farm buildings are an integral part of the rural environment, and new technologies can be used to survey, analyze, and plan interactions between farm buildings and the environment.</li> </ul>

Frontiers in Built Environment

Sustainable Design and Construction

Global Excellence in Sustainable Design and Construction: Europe 2023

Nowadays, sustainability and sustainable development are major concerns of humanity aiming to protect the Earth and ensure that all people live in peace and prosperity (<a href="#B10">United Nations, 2015b</a>). As well known, a sustainable development shall balance environmental, economic and social aspects. However, unprecedented urban growth has occurred in the last and current centuries, and more intense migration are causing many cities to be converted to megacities (<a href="#B11">Wong, 2015</a>). In this context, the construction sector is becoming more impactful on the planetary ecosystems (<a href="#B8">UNEP, 2022</a>). Cities and buildings play a fundamental role in facilitating the transition towards greener and more sustainable energy practices. At the urban level, international policies are geared towards achieving carbon neutrality by advocating for widespread accessibility and affordability of clean energy sources, consequently actively contributing to the reduction of greenhouse gas emissions to reach carbon neutrality. Furthermore, these policies are instrumental in fostering biodiversity and promoting the deployment of effective climate mitigation and adaptation measures. Besides, building-focused initiatives concentrate on the optimization of energy efficiency, prioritizing extensive deep renovation projects, and spearheading robust decarbonization efforts within the built environment (<a href="#B1">EPBD, 2018</a>; <a href="#B2">European Commission, 2019</a>; <a href="#B5">European Union, 2023</a>).Central themes are the reuse of construction materials and the embodied energy used in building production processes. A considerable amount of resources is required to construct, operate, and maintain the built environment, including buildings (<a href="#B8">UNEP, 2022</a>). Most of these resources are later converted into waste, for example, construction and demolition waste (<a href="#B4">European Commission, 2023</a>). Thus, Circular Economy is a fundamental instrument that allows to convert what is considered “waste” by some into valuable resources for other applications (<a href="#B3">European Commission, 2020</a>).Among the previous resources, energy is a very relevant one, given its relevant share compared to other economic sectors and whenever generated by fossil fuels (<a href="#B1">EPBD, 2018</a>). Thus, the adoption of Renewable Energy Sources (RES) is crucial to the decarbonization of buildings in particular and of the construction industry in general (<a href="#B7">The European Parliament And The Council Of The European Union, 2018</a>; <a href="#B6">Material Economics, 2019</a>).Existing buildings have a unique position in this debate thanks to their positive contribution to climate adaptation linked to the use of natural sources and local, raw, and durable materials that necessitate low energy for production, transportation, and recycling (<a href="#B9">United Nations, 2015a</a>). In this context, the present Research Topic collects different relevant contributions, highlighting some key issues related to sustainable design and construction, namely:&#x2022; Learning from the architecture of the past to rediscover the importance of bioclimatic strategies in modern construction.&#x2022; Role of innovative technologies in preservation.&#x2022; Resilience and adaptability in the face of severe weather conditions.&#x2022; Focus of the construction sector towards sustainable solutions and the adoption of eco-friendly materials to reduce environmental impact.&#x2022; Exploration of biological growth for building solutions.&#x2022; Importance of the research on Life Cycle Energy Analysis (LCEA) and how this methodology is shaping the understanding of the energy impact of construction materials throughout a building&#x2019;s entire life cycle.Going into more detail, the contributions of each research are explained in the following.<a href="https://www.frontiersin.org/articles/10.3389/fbuil.2022.693876/full">Picuno</a> addresses the importance of farm buildings for the sustainable development of rural areas thanks to their unique architectural and technical challenges. Historically, they have been closely intertwined with the surrounding agricultural landscape and human activities, significantly shaping the rural and cultural environment. The growing emphasis on sustainable development has prompted a renewed interest in their heritage and natural value and adaptation to the climate. This study investigates the distinctive features of farm buildings, examining their environmental conditions and showcasing various global instances of their survey, reuse, and enhancement, with a focus on Southern Italy. Additionally, it emphasizes the importance of integrating cutting-edge technologies to preserve and promote this rural building heritage. The research also highlights the collaboration among various sectors for effectively supporting rural improvement through education and knowledge-sharing among students, practitioners, and stakeholders.<a href="https://www.frontiersin.org/articles/10.3389/fbuil.2022.766652/full">Booth and Jankovic</a> examine the impact of severe weather conditions on the preservation of historic structures. Their study explores the potential of innovations of bio-augmented self-repair materials to improve building resilience and reduce maintenance activities. By encapsulating bacteria within multiple layers of limewash, they demonstrate how atmospheric carbon can be absorbed, thereby minimizing carbon-emitting maintenance processes. The materials used for bacterial encapsulation and nutrient delivery, such as hydrogels, alginates, and biofilm-based biopolymers, have been presented, emphasizing the possibility of developing a self-renewing sacrificial limewash in future research. Additionally, the study discusses the potential application of microbe-enhanced carbon-capturing limewash, particularly in improving the performance of sustainable materials like hemp-lime bio-composites.<a href="https://www.frontiersin.org/articles/10.3389/fbuil.2022.965145/full">Brandić Lipińska et al.</a> examine the potential and challenges of using mycelium-based bio-composites for both earth and space applications. Their research highlights these composites’ fire-resistant and insulating properties, underlining their adaptability to different environments and minimizing energy expenditure. A roadmap of available technologies is designed, suggesting recommendations for further development. Subsequently, they explore how controlled biological growth can facilitate fabrication, assembly, and maintenance processes, resulting in resilient structures suitable for sustainable building solutions in long-duration space missions and extraterrestrial habitats.<a href="https://www.frontiersin.org/articles/10.3389/fbuil.2022.975071/full">Schenk and Amiri</a> focus on LCEA as an essential tool for assessing the energy impact of construction materials. Their study compares the performance of embodied, operational, and demolition energies for 100 timber, concrete, and steel buildings. The findings demonstrate that, on average, the embodied energy of timber buildings is 28%–47% lower than concrete and steel buildings, respectively. The mean and median values of embodied emissions are 2.92 and 2.97&nbsp;GJ/m2 for timber, 4.08 and 3.95&nbsp;GJ/m2 for concrete, and 5.55 and 5.53&nbsp;GJ/m2 for steel buildings. Otherwise, operational energy consumption is influenced by energy supply systems and building design elements. Surprisingly, demolition energy has a minimal contribution to the overall life cycle energy.Together, these pioneering studies pave the way for more sustainable and environmentally conscious approaches to construction practices, underscoring the critical need for continued research and development in this field.PS: Writing&#x2013;original draft, Writing&#x2013;review and editing. EL: Writing&#x2013;original draft, Writing&#x2013;review and editing. SC: Writing&#x2013;review and editing.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.The handling editor GS declared a shared affiliation with the author EL at the time of review.The authors declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.

Editorial: Global excellence in sustainable design and construction: Europe 2023

Extreme weather conditions increase the frequency of regular maintenance on heritage buildings and cause erosion of traditional materials. Developments in bio-enhanced self-repair materials provide an opportunity to improve building performance and reduce the frequency of costly maintenance schedules. The microbial sequestration of carbon by bacteria, encapsulated and layered into several limewash coats, facilitates capturing atmospheric carbon and reduces carbon-generating maintenance regimes. The use of hydrogels, alginates and biofilm derived biopolymers as novel bacterial encapsulation and nutrient delivery vehicles is discussed and the opportunity to develop self-healing sacrificial limewash as a future research project. Microbial enhanced carbon-fixing limewash may also offer a broader application to improve the performance of sustainable materials such as hemp-lime bio-composites as a fast-forward projection of problems and solutions with these materials in the future.

Extreme weather conditions increase the frequency of regular maintenance on heritage buildings and cause erosion of traditional materials. Developments in bio-enhanced self-repair materials provide an opportunity to improve building performance and reduce the frequency of costly maintenance schedules. The microbial sequestration of carbon by bacteria, encapsulated and layered into several limewash coats, facilitates capturing atmospheric carbon and reduces carbon-generating maintenance regimes. The use of hydrogels, alginates and biofilm derived biopolymers as novel bacterial encapsulation and nutrient delivery vehicles is discussed and the opportunity to develop self-healing sacrificial limewash as a future research project. Microbial enhanced carbon-fixing limewash may also offer a broader application to improve the performance of sustainable materials such as hemp-lime bio-composites as a fast-forward projection of problems and solutions with these materials in the future.

Novel biodesign enhancements to at-risk traditional building materials

Around 40% of global energy consumption can be attributed to the construction sector. Consequently, the development of the construction industry towards more sustainable solutions and technologies plays a crucial role in the future of our planet. Various tools and methods have been developed to assess the energy consumption of buildings, one of which is life cycle energy analysis (LCEA). LCEA requires the energy consumption at each stage of the life cycle of a product to be assessed, enabling the comparison of the impact of construction materials on energy consumption. Findings from LCEAs of buildings suggest that timber framed constructions show promising results with respect to energy consumption and sustainability. In this study a critical analysis of 100 case studies from the literature of LCEAs conducted for residential buildings is presented. Based on the studied material, the embodied, operational, and demolition energies for timber, concrete and steel buildings are compared and the importance of sustainable material selection for buildings is highlighted. The results reveal that on average, the embodied energy of timber buildings is 28–47% lower than for concrete and steel buildings respectively. The mean and median values of embodied emissions are 2,92 and 2,97 for timber, 4.08 and 3,95 for concrete, and 5,55 and 5,53 GJ/m2 for steel buildings. Moreover, the data suggests that the energy supply system of residential buildings plays a larger role in the operational energy consumption that the construction material. In addition, climate conditions, insulation detail, windows and building surfaces, and building direction are the other energy use role players. Finally, it was found that the demolition energy contributes only a small amount to the total life cycle energy consumption. This study demonstrates the significance of embodied energy when comparing the life cycle energy requirements of buildings and highlights the need for the development of a more standardised approach to LCEA case studies.

Around 40% of global energy consumption can be attributed to the construction sector. Consequently, the development of the construction industry towards more sustainable solutions and technologies plays a crucial role in the future of our planet. Various tools and methods have been developed to assess the energy consumption of buildings, one of which is life cycle energy analysis (LCEA). LCEA requires the energy consumption at each stage of the life cycle of a product to be assessed, enabling the comparison of the impact of construction materials on energy consumption. Findings from LCEAs of buildings suggest that timber framed constructions show promising results with respect to energy consumption and sustainability. In this study a critical analysis of 100 case studies from the literature of LCEAs conducted for residential buildings is presented. Based on the studied material, the embodied, operational, and demolition energies for timber, concrete and steel buildings are compared and the importance of sustainable material selection for buildings is highlighted. The results reveal that on average, the embodied energy of timber buildings is 28–47% lower than for concrete and steel buildings respectively. The mean and median values of embodied emissions are 2,92 and 2,97 for timber, 4.08 and 3,95 for concrete, and 5,55 and 5,53 GJ/m2 for steel buildings. Moreover, the data suggests that the energy supply system of residential buildings plays a larger role in the operational energy consumption that the construction material. In addition, climate conditions, insulation detail, windows and building surfaces, and building direction are the other energy use role players. Finally, it was found that the demolition energy contributes only a small amount to the total life cycle energy consumption. This study demonstrates the significance of embodied energy when comparing the life cycle energy requirements of buildings and highlights the need for the development of a more standardised approach to LCEA case studies.

Life cycle energy analysis of residential wooden buildings versus concrete and steel buildings: A review

A critical aspect of human space exploration and eventual settlement is the ability to construct habitats while minimizing payload mass launched from Earth. To respond to this challenge, we have proposed the use of fungal bio-composites for growing extra-terrestrial structures, directly at the destination, significantly lowering the mass of structural materials transported from Earth and minimizing the need for high mass robotic operations and infrastructure preparations. Throughout human history, the construction of habitats has used biologically produced materials, from bone and skins to wood and limestone. Traditionally, the materials are used only post-mortem. Currently, the idea of working with living biological organisms, and the phenomenon of growth itself, is of increasing interest in architecture and space applications. Here, we describe the use of mycelium-based composites as an alternative, biological approach for constructing regenerative and adaptive buildings in extrem environments and extraterrestrial habitats. It is a continuation of our research program initiated under the auspices of the “Myco-architecture Off Planet” NASA NIAC Team. These composites, which are fire-resistant, and insulating, do not consist of volatile organic compounds from petrochemical products and can be used independently or in conjunction with regolith, could employ the living biological growth in a controlled environment, for the process of material fabrication, assembly, maintenance, and repair, providing structures resilient to extra-terrestrial hazards. Here we outline the potential and challenges of using bio-composites for Earth and space applications. We describe how these might be addressed to make this biological approach feasible, providing new, growing materials for designing and building sustainable habitats, both on Earth and for long-duration space missions.

A critical aspect of human space exploration and eventual settlement is the ability to construct habitats while minimizing payload mass launched from Earth. To respond to this challenge, we have proposed the use of fungal bio-composites for growing extra-terrestrial structures, directly at the destination, significantly lowering the mass of structural materials transported from Earth and minimizing the need for high mass robotic operations and infrastructure preparations. Throughout human history, the construction of habitats has used biologically produced materials, from bone and skins to wood and limestone. Traditionally, the materials are used only post-mortem. Currently, the idea of working with living biological organisms, and the phenomenon of growth itself, is of increasing interest in architecture and space applications. Here, we describe the use of mycelium-based composites as an alternative, biological approach for constructing regenerative and adaptive buildings in extrem environments and extraterrestrial habitats. It is a continuation of our research program initiated under the auspices of the &#x201c;Myco-architecture Off Planet&#x201d; NASA NIAC Team. These composites, which are fire-resistant, and insulating, do not consist of volatile organic compounds from petrochemical products and can be used independently or in conjunction with regolith, could employ the living biological growth in a controlled environment, for the process of material fabrication, assembly, maintenance, and repair, providing structures resilient to extra-terrestrial hazards. Here we outline the potential and challenges of using bio-composites for Earth and space applications. We describe how these might be addressed to make this biological approach feasible, providing new, growing materials for designing and building sustainable habitats, both on Earth and for long-duration space missions.

Biological growth as an alternative approach to on and off-Earth construction

Farm buildings play a central role in the sustainability of the rural environment. Conceived to host biological productions, the farm building constitutes indeed an unparalleled example in the wide epistemological construction sector. Due to its peculiar interactions with the indoor and outdoor built environment, it raises architectural and technical issues different from other buildings. The role that these buildings have historically played is strictly connected with the surrounding context, due to the need of the farmer to live in close contact with agricultural land and animal husbandry. Human activities have then decisively influenced the rural environment as well as the visual perception of its landscape. The increasing sensitivity to the concept of sustainable development of the built environment is currently stimulating the valorization of farm buildings. In the present review paper, a general literature analysis of the peculiarity of farm buildings and their internal and external environmental conditions is presented. Several cases of survey, reuse and valorization of farm buildings around the world are reported as well, with special attention being paid to Southern Italy, where the results are extrapolated or generalized to other regions. Focus is also given to the wider opportunities enabled by the implementation of new technologies for the survey, analysis and planning of the interactions between farm buildings and the rural environment. The main conclusions are that farm buildings play a driving role in the rural environment, thanks to the ecological function they perform, as well as to their socio-economic and cultural heritage at the base of the rural development.

Farm buildings play a central role in the sustainability of the rural environment. Conceived to host biological productions, the farm building constitutes indeed an unparalleled example in the wide epistemological construction sector. Due to its peculiar interactions with the indoor and outdoor built environment, it raises architectural and technical issues different from other buildings. The role that these buildings have historically played is strictly connected with the surrounding context, due to the need of the farmer to live in close contact with agricultural land and animal husbandry. Human activities have then decisively influenced the rural environment as well as the visual perception of its landscape. The increasing sensitivity to the concept of sustainable development of the built environment is currently stimulating the valorization of farm buildings. In the present review paper, a general literature analysis of the peculiarity of farm buildings and their internal and external environmental conditions is presented. Several cases of survey, reuse and valorization of farm buildings around the world are reported as well, with special attention being paid to Southern Italy, where the results are extrapolated or generalized to other regions. Focus is also given to the wider opportunities enabled by the implementation of new technologies for the survey, analysis and planning of the interactions between farm buildings and the rural environment. The main conclusions are that farm buildings play a driving role in the rural environment, thanks to the ecological function they perform, as well as to their socio-economic and cultural heritage at the base of the rural development.