bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of different post-demolition autoclaved aerated concrete (AAC) recycling options
Authors: Volk R , Steins J J , Stemmermann P , Schultmann F
Published: September 2022

Autoclaved aerated concrete (AAC) is used as masonry blocks and prefabricated reinforced elements preferably in residential buildings. Due to its porous structure and mineral composition, it combines low thermal conductivity and fire resistance properties. Consequently, the popularity of AAC increases. However, due to significant AAC production volumes in many European countries since the 1960s and 1970s and given building lifetimes, strongly increasing post-demolition AAC waste volumes can be expected in the following decades. Recycling these post-demolition AAC wastes could protect primary resources and landfill capacities and reduce greenhouse gas emissions. But, recycling of post-demolition AAC is not yet established. The majority of the waste is landfilled even though landfill capacities have decreased and the legal framework conditions in Europe regarding a circular economy are becoming stricter. Therefore, new recycling options are needed. Current research approaches propose different open-loop recycling routes for post-demolition AAC, e.g. lightweight aggregate concrete, lightweight mortar, no-fines concrete, floor screed, animal bedding, oil- and chemical binders, and insulating fills for voids and interstitial spaces. Additionally, closed-loop recycling is possible and under research. Finely ground post-demolition AAC powder can be directly used in AAC production or can be chemically converted to belite (C2S) clinker to substitute primary cement in AAC production. These promising recycling options are compared regarding environmental and economic aspects. We find that the resource consumption is lower in all recycling options since post-demolition AAC helps to save primary resources. Furthermore, greenhouse gas emissions associated with the substituted primary resources are saved - especially when substituting primary cement in closed-loop recycling. In economic terms, increasing landfill costs could be avoided, which leaves a considerable margin for the cost of pre-processing, transport and recycling. The results can help decision-makers to implement circular management for AAC by fostering post-demolition AAC recycling and reducing its landfilling.
Towards a Climate Neutral Housing Strategy for Egypt – Performance based Living-Action Levels and Responsibilities
Authors: Nadim W
Published: September 2022

Egypt’s population has recently exceeded 100 Million inhabitants; a figure that is anticipated to double within the coming 20-30 years. At a current 2% annual growth rate, changing socio economics needs, and anticipated demographic change; more than ever, has housing provision become a challenging proposition. Residential construction in Egypt amounts to 21% of the total construction output by value in 2015 in Egypt (9.548 Billion LE) which is almost equivalent to the construction output by value of powerplants (EGP 9.67Billion LE). In addition, the construction and demolition waste accounts for 44% of the total solid waste of 94 Million tons produced in Egypt. Given the scarcity of resources, the resultant CO2 emissions and pollution, in addition to Egypt’s commitment to the World Sustainable Development Goals (SDGs); this paper, adopts a qualitative approach - literature review, to identify Egypt’s major housing challenges and potential solutions in light of SDG11. In this context, the concept of climate neutral design is investigated, different assessment tools are critically reviewed; and major components for strategy development are concluded in terms of levels and responsibilities. These are then used as a reference to reflect on Egypt housing strategies issued in 2016. This paper is exploratory in nature and is anticipated to furnish the ground for the following phase of the research to devise an action driven climate neutral housing strategy for Egypt.
Development of environmental benchmarks for the Belgian residential building stock
Authors: Mouton L , Trigaux D , Allacker K , Crawford R H
Published: September 2022

Over recent years Belgium has made meaningful effort in adopting Life Cycle Assessment (LCA) in building practice to improve building environmental performance. Today, architects can compare the environmental performance of different building designs with an online calculation tool that incorporates the national LCA method. However, they are still lacking environmental benchmarks to position themselves within current building practice. Furthermore, such benchmarks play an important role in the development of environmental targets in building regulation. In this research, benchmarks are defined for new residential buildings in Belgium. A bottom-up approach is followed consisting of a statistical analysis of reference buildings to define limit, reference and best practice values. The buildings are based on four representative typologies for Belgium, ranging from detached houses to apartments. Different variants are assessed including various energy performance levels and construction types (solid versus timber). The buildings’ life cycle impacts are calculated including the embodied (material) and operational (energy) impacts. Results are reported both for an aggregated environmental single-score and for Global Warming Potential (GWP). The calculated reference values for life cycle and embodied GWP (20 and 7 kgCO2eq/m2.year) are comparable to existing benchmarks in the literature. The results further highlight that building compactness provides the largest impact reduction, followed by construction type. Finally, limitations are discussed and recommendations are formulated for developing future benchmarks.
Filling the gaps Circular transition of affordable housing in Denmark
Authors: Larsen V G , Tollin N , Antoniucci V , Birkved M , Sattrup P A , Holmboe T , Marella G
Published: September 2022

The building industry accounts for about 40% of all climate impacts, stemming from construction and renovation processes, use of buildings and demolition, disposal and recycling of buildings and building materials. The Danish Parliament passed a Danish Climate Act in 2020 to reduce greenhouse gas emissions by 70% by 2030, and an action plan in 2021 to create a Circular Economy (CE) in DK that can support the achievement of climate neutrality by 2050. About 20% of the Danish housing stock is affordable housing with approx. 560.000 affordable housing homes, inhabited by nearly 1 million out of 5.8 million people. In 2020 the Danish Government decided on the most significant overall housing agreement to set aside EUR 5,5 billion for ‘Green renovations’ and the building of new affordable housing. Building and renovating affordable housing in Denmark can thus become significant drivers for the Danish building industry’s transition to CE. Therefore, developing integrated tools and methodologies for life cycle thinking and CE assessment for the built environment is necessary. We have identified four significant gaps in this endeavour in a previously released literature review: For CE to succeed, it is necessary to take a circular view of the life cycle of buildings, which includes the service life phase, the reuse phase and the recycle phase; To achieve CE, it is necessary to continue research regarding the possibilities of integrating Life Cycle Assessment (LCA), Life Cycle Cost (LCC) and Social Life Cycle Assessment (S-LCA) into Life Cycle Sustainability Assessment (LCSA); S-LCA needs further maturation and development; It is imperative to focus upon operationalising LCSA for practitioners in all phases of a building’s life cycle. This paper aims to outline a strategy for analysing and discussing these four gaps and their interrelation in-depth and suggest an action research proposal to understand better how to bridge the gaps from a research perspective.
The potential of vertical extension at the city scale
Authors: Gillott C , Davison J B , Densley Tingley D
Published: September 2022

The UK construction sector is central to the climate and housing crises and must now deliver vast amounts of residential accommodation whilst reaching net zero emissions by 2050. Housing provision through the vertical extension of existing buildings offers opportunity to achieve this, reducing embodied carbon emissions and creating more efficient high-density settlements. In England, permitted development (PD) rights allow for residential vertical extensions without the requirement for conventional planning permission. Despite this, and due to limited uptake of PD rights and a lack of existing studies, the potential for housing provision through widespread extension is unknown. This paper develops a framework to assess the ability of vertical extensions in providing housing at different scales and applies this to Sheffield, England. The generation of new dwellings through PD vertical extension could house up to 175,000 in Sheffield, with detached buildings and those in residential use being most suited to extension. PD rights favour the enlargement of existing dwellings over the generation of new residential units, potentially limiting their effectiveness in tackling the housing crisis.
A Circular and Bio-based Renovation Strategy for Low-income Neighbourhoods
Authors: Cihan Kayacetin N , Versele A
Published: September 2022

The impact of climate change is expected to increase in the following decade. Possible effects on the built environment are identified as urban heat stress, air pollution, extreme weather conditions, etc. As a result, there is an increase in disease and mortality specifically in the cities among the vulnerable citizens such as elderly people and children. Moreover, many cities worldwide are in the evolution of urbanization which leads to increased carbon emissions as well as a demand for more material production and waste. Consequently, the construction industry embodies great potential for reaching the energy and carbon mitigation goals. For regeneration of the built environment, the European directives requires for the renovation of existing building stock as quick as possible. In Flemish context, cities stimulate renovation projects on a systematic and planned basis, by defining ‘urban renovation districts’ which received special financial facilities and subsidizing. Consequently, there is a growing demand for affordable housing in combination with a shortage of qualitative and energy efficient housing opportunities. In the last decades, there has been an intensive effort to develop different retrofit strategies, but there is a lack of comprehensive approach that delivers innovative technical solutions such as circular and bio-based construction methods as a solution to the increased housing demand of vulnerable people. For this purpose, this study combines the efforts of two initiatives, (1) Interreg Circular Bio-Based Construction Industry (CBCI) and (2) the innovative financial policy instrument of subsidy retention for low-income groups (refers to citizens living in poor quality houses with insufficient economic means & social skills to renovate). The study has the ambition to explore the coherence between technical, economical, legal, social aspects for circular urban retrofit strategies. Circular building materials and methods were developed and tested in real-life setting with construction of a prototype living lab (LL) in Technology Campus, Ghent. Depending on the results from the LL, an urban renewal strategy for Flemish districts is proposed by using subsidy retention on macro-economic and social level. The scenario is envisaged as a collective approach with the local community in which the vulnerable users also benefit as direct participants to the research.
Circularity evaluation as guidance for building design
Authors: Nemeth I , Schneider-Marin P , Figl H , Fellner M , Asam C
Published: September 2022

Resource scarcity and global warming call for ambitious strategies in the construction sector to meet the ever-growing demand for indoor spaces with minimal resource consumption and positive environmental impacts. In line with the need to introduce circular economy in the construction sector, the German Public Sustainability Certification System (BNB) is revising its indicator for disassembly, separation and reuse. The proposed assessment is intended to guide in the planning process and to point out challenges and potentials of the circular economy by making the complex interactions and requirements comprehensible in detail. The continuity of the assessment from the building material to the building component to the entire building allows users to track the impact of changes made at each level of aggregation. Based on extensive background research, end-of-life categories are assigned to building materials according to their reusability, taking into account assembly techniques and adjacent, associated materials. Example building components illustrate the method and show the impact of design changes. At the building level, the quantity determination of materials in the end-of-life condition allows transparent comparison of different design variants and documents in detail the material inventory for use in building material passports. Future developments envision the inclusion of building services in the circularity assessment, benchmarking of circularity at the building level, and integration of circular qualities into life cycle analysis calculations.
Critical Indigenism as Approach for Sustainable Urbanization
Authors: Stürwald S , Mohamed F , Schmidt W , Reitz J , Maboea D
Published: September 2022

Within the next 30 years, cities will grow dramatically. Rural areas will become new urban centers, and open spaces will transform into urban cityscapes. Population growth, demolition of natural landscapes, and urbanization are fuelling the already imminent threat of climate change. Indigenous structures with their own “critical regionalism” touch on a wide range of cultural, economic, and societal aspects. The authors of this paper examine the possible influence of indigenous vernacular structures and the important regional dependencies in African communities. Paradigm would be the use of materials, typologies, building layouts, urban planning, and ecological concepts as well as the question of the importance of a defined urban image. The paper is based on results derived from interdisciplinary and intercultural collaboration within the framework of the Female Academic Leadership Network for Conscious Engineering and Science towards Sustainable Urbanisation FALCONESS.
Urban qualities for dense mixed-use spaces. Theses, case studies and a toolbox for integrated tangible urban planning.
Authors: Schuchert C L , Schwehr P , Gabriel B
Published: September 2022

The built environment is under pressure. Climate change, migration and social inequalities challenge previous urban planning concepts and will change our cities. The task is to transform the sustainable city of the future into a climate-friendly and socially just living space. Solving these challenges requires an integrated quality discourse with all actors based on tangible structural-spatial situations. In the BBSR research project “Qualities of Urban Zones”, contributions for an early in-depth quality discourse were developed based on the new building zone category “urban zones”. Urban zones are regarded as a future-oriented concept for sustainable densified districts and a diverse, ever-changing mix of uses. This paper presents the specific context and main findings as “theses of urban quality” as well as potential applications for MU. The authors propose guidelines to improve process quality and illustrate exemplary tangible structural-spatial as well as process-related “design elements”. A toolbox with instructions and templates to design and implement scenario-based workshops supports an integrated quality discourse in urban development.
Matching energy targets, stakeholders’ needs and modelling choices in developing urban energy scenarios
Authors: Maiullari D , Palm A , Wallbaum H , Thuvander L
Published: September 2022

In order to meet greenhouse gas reduction goals, cities need to develop robust energy transition strategies relying both on the local capacity of combining social, economic and environmental perspectives in the decision-making process and on the collaboration between different actors to achieve knowledge and data integration. Scenarios are well-established methodological instruments to guide decisions in energy and spatial planning and have been employed to compare possible future pathways and envision the consequences of implementing decarbonization measures. However, qualitative and quantitative scenarios approaches are often disconnected. With the primary goal of supporting the implementation of the energy plan, this study develops for the City of Gothenburg a participatory method to support the alignment of qualitative and quantitative scenarios approaches. Decarbonization actions and drivers of change were discussed and prioritized in workshop sessions with representatives from the energy supplier(s), municipal administrations (city planners, environmental department), and researchers to develop relevant qualitative scenarios descriptions. Based on this, a list of requirements for quantitative scenarios analysis is developed to be, in a next step, translated and integrated into urban building energy models. Findings indicate the importance of early knowledge integration from different fields and highlight the lines of advancement in urban energy modelling to facilitate decision-making towards successful implementation of decarbonization targets.
Integration of life-cycle assessment in a multimodal building design approach
Authors: Apellániz D , Aziz S , Weber M , Brechenmacher E , Ogarkova S , Gengnagel C
Published: September 2022

Decades of rapid and widespread digitization of our living and working environments have not yet brought about a comprehensive qualitative improvement of our built environment in terms of sustainability and functional and aesthetic performance. The designs of the future must be much more consistently concerned with optimizing the multimodal performance of human spaces. This paper presents a design approach to implement and combine life-cycle assessment with different simulation methods such as energy efficiency, daylight analysis, acoustics, noise insulation, structural analysis and fire protection in order to provide the designer with tools to evaluate how architectural decisions affect the building performance and its environmental impacts. This approach was applied by the architecture students of a master course at the Universität der Künste Berlin. They were given the program of a building to be constructed in the Siemensstadt in Berlin and they implemented this methodology to come up with different sustainable designs. This paper also discusses the results of this course and empathizes how the implementation of simulation tools does not constrain the possibilities of the design process, but it enriches it and leads to a more sustainable built environment.
Energy – Comfort – Environment: What matters most? A multi-criteria assessment of a residential apartment
Authors: Manolitsis A , Zacharis A , Atsonios I , Detsi M , Bonou A , Stamatiadou M , Mandilaras I , Founti M
Published: September 2022

In this study, a multi-criteria assessment approach is performed for a residential apartment located in Athens, for a combination of different energy systems, building envelope and shading systems. 24 alternative cases in total are fully simulated via EnergyPlus software aiming to the calculation Key Performance Indicators (KPIs) in terms of energy consumption for heating and cooling, thermal comfort, visual comfort and environmental impact. The results of KPIs are fed to a decision-making process that takes into consideration the preferences of stakeholders. The optimum solution is selected by the use of the Analytic Hierarchy Process (AHP). In the most optimum scenario, the potential of primary energy savings and CO2 emissions are approximately 35% while the discomfort hours for thermal and visual comfort are respectively 17% and 67% less than the cases with the worst comfort conditions. The results suggest that such a multi-criteria assessment approach can be useful at an early stage of building design or renovation in order to better inform decisions and avoid sub optimizations.
Mission accomplished? – 6 Years of InData - International open Database Network Structure for Sustainable Construction
Authors: Brockmann T
Published: September 2022

InData (International open data network for sustainable construction) started in 2015 as a voluntary initiative with the goal to establish an International open Database Network Structure for construction products based on EPD (environmental product declaration) information. In 2022 InData can proof its results by its release of the InData network with international participating databases. A key precondition was offering and giving support for producing machine readable EPD/LCA (life cycle assessment) data in a harmonized data format. All participants of the InData Network have comitted to the format, including compliance rules. Beyond that, the works of InData have international significant relevance, as InData could implement its works in Standardization. And also, further key stakeholders have adopted the concept of an open database network structure. In this paper, the goals, results, and their relevance, as possible future key issues are presented.
Model projects as tools for cooperative urban development: The case of Haus der Statistik in Berlin.
Authors: Gundlach K , Marlow F , Peters N , Wall R
Published: September 2022

According to the New Leipzig Charter, urban development processes should be ‘a matter of all’ – the common good, climate protection and environmental justice, to name but a few aspects. Currently, new forms of innovation seeking models emerge within this context of sustainable urban planning practice - for example, real-world field laboratories and model projects. Haus der Statistik in Berlin is one such ‘model project for cooperative and common-good-oriented urban development’. It is widely recognized for its demand- and process-driven approach, as well as its project development being based on public-civic partnership. As anthropological and urbanist researchers and practitioners involved in the project, we give a situated account on the socio-political elements of the Haus der Statistik’s public-civic partnership and investigate the potentials of this model for a more sustainable urban development. The structure of the paper is threefold: Firstly, we introduce the so-called model project Haus der Statistik and its common-good orientated agenda and relate it to sustainability goals of the New Leipzig Charter. Secondly, we introduce the specific public-civic-framework in regard to its methodological framing within the context of model projects and comparable approaches that focus on collaborative, transdisciplinary and innovative methods, such as real-world field laboratories. Thirdly, we reflect on the elements of the public-civic-partnership framework that have been explored and developed at the ‘model project’ Haus der Statistik since 2015 and its implications for a more sustainable urban development.
Planning for sharing neighbourhoods – Negotiating sustainable transition with adaptive governance models
Authors: Baer D , Lindkvist C
Published: September 2022

Thorough sharing is discussed as a promise concept to reduce emissions and enable sustainable development, little is known how the diverse approaches of sharing ranging from Collective Commons to the Sharing Economy can be incorporated in the development of the built environment. In this study, we set the spotlight on sharing and how it could be implemented as a guiding principle in neighbourhood development. We build our study on an empirical case study within the new planned zero emission neighbourhood development of Ydalir within the city of Elverum, Norway. Building on document analysis, accompanying research and a one-day workshop with diverse stakeholders, we identified respective sharing solutions to create social value for future Ydalir residents. The findings let us draw the picture of an adaptive governance model to initiate and facilitate sharing within a multi-stakeholder setting of a new planned neighbourhood development.
Life cycle assessment of tunnel structures: Assessment of the New Austrian Tunnelling Method using a case study
Authors: Hopf Bernhard W. , Hoxha Endrit , Scherz Marco , Heichinger Harald , Kreiner Helmuth , Passer Alexander
Published: September 2022

One important measure to combat progressing climate change is compliance with and under no circumstances to exceed the decreasing greenhouse gas budget. Every economic sector must strive to make its ecological contribution to achieve this objective. The construction sector is largely responsible for these negative environmental burdens. Although tunnels are considered to have extensive energy and material consumptions the literature has failed to present their environmental impacts. Aimed at this knowledge gap, the objective of this study is to present the life cycle assessment (LCA) of a tunnel construction project situated in Bulgaria. The study analyzes the impacts of the New Austrian Tunnelling Method (NATM) using the case study “Modernization of Railway Section Elin Pelin-Kostenets – Lot 3”. Moreover, by applying dominance and sensitivity analyses, the environmental drivers and optimization potential for reducing greenhouse gas emissions are identified. The results show that steel, shotcrete, and concrete, contribute the most to the global warming potential indicator and are responsible for 85% of this. Furthermore, the life cycle stages for the production of materials and components have a share close to 85 % of the total global warming potential. These findings may help future tunnelling construction projects to improve the environmental performance and thus to combat the alarming development of climate change.
Influence of traffic load on the environmental impacts of roads: A1 and A2 highways in Austria
Authors: Hoxha E , Scherz M , Passer A
Published: September 2022

Professionals should aim to significantly reduce greenhouse gas (GHG) emissions by implementing the best road construction technologies to develop low-carbon projects. Although the traffic loads vary over the road length, the environmental impacts are assessed based on the average values of the traffic loads. Consequently, there is a gap between reality and the impacts calculated with fixed traffic load. This paper aims to assess the gap in terms of the environmental impacts of two roads by considering both a constant and a variable traffic load. With the help of a life cycle assessment (LCA), the environmental impacts of the A1 and A2 highways in Austria are calculated. We have calculated the impacts in the first scenario by considering an average traffic load. In the second scenario, based on real measurements, the environmental impacts of both highways are calculated for a variable traffic load. In the end, the results show a gap in the range of 25 %. This difference was because some parts of the roads required frequent repair. Besides, we figured out the optimal thickness of the wearing course, which improves the impact calculation and makes it less likely that the results will be different along the length of the road.
Aligning actors in a road renovation project by a co-design process: the road to circularity?
Authors: Entrop A G , Hagen L , van Leeuwen J P
Published: September 2022

In a circular economy, the aim is to close material loops that retain the highest utility, quality, and value of products, components, and materials. The environmental impact of the material used in constructing, maintaining, and renovating roads is severe. Within the European H2020 project CityLoops, the municipality of Apeldoorn prepares a circular road renovation project, yet wonders: how to align the actors in public infrastructural projects to come to a circular and, at the same time, executable project? A literature study and experiment were conducted. The experiment consisted of a co-design process aiming for the renovation of a residential road constructed in the late seventies. When conducting road renovation, multiple departments within the municipal organization and different external organizations need to collaborate. To them, circular material usage was introduced as a new specific sustainable objective, while traditional constraints, like time and costs, remained. It was visualized in a process journey, showing who is expected to meet which collaborative milestones and when. The insights from this experiment might help other municipalities, principals, and contractors to come to circular design processes in the road construction industry.
Ecological performance of reusable load-bearing constructions
Authors: Fadai A , Stephan D
Published: September 2022

This study provides an overview of sustainable reusable load-bearing constructions as a contribution to the debate over whether building construction provides the building industry with the best and most environmentally friendly qualities. By contrasting their building-specific features, it demonstrates the benefits and drawbacks of particular structural elements and envelope solutions and ecological aspects using various system boundaries of life-cycle assessment (LCA). Following a careful consideration of ecological factors and sustainable circular economy criteria, a structural component that is sustainably optimized is defined. This component should be chosen based on external conditions. By selecting environmentally friendly building materials and proper connecting procedures that enable separability, resource-efficient and sustainable buildings can be achieved. Both the selection of load-bearing elements and the necessary insulating material have a significant impact on the ecological performance and reusability options of the components. The elements of homogeneity, separability, and pollutant-freeness play a significant influence in the reuse process, namely in terms of details and construction type in general, as well as the ways of reusing and recycling them. Sustainable solutions for load-bearing building components can be created by simultaneously investigating environmentally friendly building materials and the structure of the components. This paper illustrates how the natural resources can be used both optimally and sustainably. It presents a conceptual framework for scenario development of the LCA of load-bearing structures, their effect on the design and decision-making process. There is a potential of increasing total resource efficiency at the building level with a suitable combination of the material components employed at the component level. Because of this, the overall energy efficiency and its consequent ecological impacts are the main topics of this study.
AESA approach applied to mineral and metal resources use sustainability in the building sector: The MiMOSA method
Authors: Bendahmane N , Gondran N , Chevalier J
Published: September 2022

Considering the increase of natural resource use, humanity is facing the problem of resource depletion. The building sector is a major consumer of resources. The most consumed resources are mineral and metal resources. Thereby, the identification, and then optimisation, of mineral and metal resource use in the building sector appears as a necessity. One tool to quantify the use of those resources is LCA. Currently, several authors develop absolute environmental sustainability assessment (AESA) methods, combined with LCA, to compare the pressures of the studied project with the global carrying capacity of the planet. However, most of the AESA approaches do not actually include normalization factors about the use of resources, and in particular mineral and metal resources. Besides, the mainly used LCIA characterization methods of mineral and metal resources present several limits when applied to Circular Economy projects within the building sector. Thereby, the goal of this research project is to answer the following question: Can the consumption of mineral and metal resources for a given building project be considered sustainable? To answer this question, a methodology was developed. This methodology is inspired by the AESA approach by proposing a sustainable resource budget for each mineral or metal substance and will combine the MFA methods to the LCA method to calculate sustainability indicators for each mineral and metal resource. The Mineral and Metal absOlute Sustainability Assessment (MiMOSA) method integrates the circular economy actions and considers an appropriate spatial scale for each resource and will be presented in this paper.
Sensitivity analysis of building energy models due to the shading effect of surrounding buildings to support building renovation
Authors: Daneshfar M , Hartmann T , Rabe J
Published: September 2022

Building energy simulation is an analytical process to help building owners and designers evaluate the energy performance of the building. Uncertainty in the building energy modelling influences the building renovation from two perspectives: 1) calculating as-built energy consumption, 2) analysing the energy performance of renovation alternatives. Energy models can enhance by incorporating contextual and surrounding data. To this aim, we conducted a systematic study to investigate the effect of surrounding buildings in different distances, heights, and orientations in studying the as-built energy consumption of an example building. The research also investigates the impact of a specific surrounding building on the energy performance of three different renovation alternatives, namely the modification of windows, external walls, and roofs. The results demonstrate that a higher height to distance ratio of the surrounding buildings influences the energy consumption more dramatically. In addition, a surrounding building located in the south direction causes more effect on the energy result than other directions when the building is in the northern hemisphere. For renovation scenarios, if there is a specific building in the south of the building under renovation, the window modification leads to less energy consumption than other renovation scenarios. The paper discusses that for renovation projects, an initial examination of surrounding buildings before selecting the renovation alternative is crucial; since different placements of surrounding buildings can affect the performance of renovation scenarios differently, which can cause a variation in the cost of renovation.
Towards Climate Neutral Buildings – Case Study of Positive Building in Brussels: Gare Maritime project
Authors: Bockelandt T , Jamali N
Published: September 2022

The Gare Maritime is a former freight station in Brussels that has been vacant for quite some time. The exceptional architectural features of the building have encouraged the owner to maintain and restore the building and create commercial and office spaces. To this end, the large hall is renovated into a well-insulated envelope in which the office volumes are placed independently. These spaces are climatised by using a geothermal loop with ATES to which individual heat pumps are connected: Cooling is provided in a passive way and heating is done through the heat pumps. A 3MW of PV-panels installations is on the existing roof structure. By means of the insulation package and an intelligent control system for openable parts of the building envelope, a comfortable indoor climate is created within the hall itself in which activities can take place for most of the year. The moderate temperature in the hall leads to a low energy consumption of the built-in volumes and losses to the outside environment are drastically limited. The ventilation is supplied in all spaces using a mechanical system. Inside the office-volumes, a perfect flexible climate is guaranteed by means of chilled ceilings, which also act as acoustic absorption material. Large window-openings maximize the benefit of daylight penetrating the building. By using variable frequency pumps, variable air volumes and daylight controlled light fixtures and sensors; the energy use of the building is minimized. Besides the 100% refurbishment of the existing structure, the design team developed a structural strategy of prefabricated, wooden constructions for the built-in office spaces, making it a perfect example of the reduction of the use of natural resources and maximizing the amount of absorbed CO2. To come to the overall strategy of this renovation, numerous simulations, brainstorms and gathering of references were conducted from the early-stages. The start design parameters of the project were determined through simulations before the elaboration of an architectural design. This process allowed the client to take decisions based on robust data relating to attainable comfort, investment costs and environmental considerations. Overall, the project is Energy Positive Building
Green-blue infrastructure in the built environment – sustainable and resource-saving designs for urban structures and open spaces
Authors: Stangl R , Minixhofer P , Wultsch T , Briefer A , Scharf B
Published: September 2022

Urban grey infrastructure, as it generally consists of monofunctional, sealed, impervious, heating up and reflecting surfaces, has led to a series of serious challenges (urban heat stresses, loss of biodiversity, flood risks and natural hazards) decreasing urban resilience. Ongoing construction activities result in irreversible soil consumption and loss of its numerous and vital functions. However, a common understanding has been evolving that the establishment of green-blue infrastructure (GBI) supports compensating for functional losses, as they are integrative and provide pervious, absorbent, shading and non-heating up surfaces. We present a concept to holistically interconnect stand-alone approaches to improve and support constructional design for transforming green open spaces addressing specifically urban landscape construction and building greenery. The underlying state of knowledge emerges from currently four ongoing projects on advancing GBI for re-establishing ecosystem functions and diverse habitats: 1. The Circular Soil Concept targets the reuse of excavated soil materials from construction sites to produce engineered soils. These are applied as functional vegetation substrates for landscape construction and installing building greenery, saving scarce soil resources while generating large scale and vegetated areas with climate change adaptation performance. 2. The StreetTREE-Planter is designed to install urban trees in a given street infrastructure. The advanced planter systems will support extended tree lifespans, microclimatic benefits, flood protection and urban resilience. The design is based on targeted rainwater harvesting for irrigation management in alignment with water requirements and the desired microclimatic performance. 3. The GLASGrün projects generates plant-based shading designs for glass facades. As plants and their leaves do not heat up from solar radiation, vertical greenery is promising, however challenging, for green shading of glazed surfaces and for indoor and outdoor microclimatic regulation. 4. The INReS rainwater management tool was developed as a prototype web application to integrate sustainable, plant-based rainwater management systems into BIM-(Building Information Modeling)-based construction projects. It provides up-to-date design for the wider public and specific planning guidelines. In synthesis with the present and upcoming findings of these projects, a parameter-based and BIM-compatible GBI-design management tool is foreseen to better and sustainably integrate GBI systems into construction projects, and to consider the resource question.
Analytical framework for the analysis of co-benefits, conflicts and trade-offs of urban heat mitigation strategies
Authors: Xiong L , He B-J
Published: September 2022

Many cities are undergoing urban heat challenges because of heat waves and urban heat islands (UHIs). During urban planning and design, properly adding cooling interventions, namely urban heat mitigation strategies, into cities and communities are essential to address urban heat challenges. However, cities are required to provide a variety of functions (e.g., buildings, transportation, park) and meet the requirements convenience, safety, health, comfort and wellbeing. Such functions and requirements result in some co-benefits, conflicts and trade-offs, promoting and constraining the application of urban heat mitigation strategies. However, the possible co-benefits, conflicts and trade-offs have not been well documented, where the improper use of cooling strategies may lead to unintended consequences. Therefore, it is essential to understand the co-benefits, conflicts and trade-offs of different cooling interventions. In particular, this study aims to develop an analytical framework for the analysis of the co-benefits, conflicts and trade-offs of different mitigation techniques. Mitigation techniques considered includes four clusters such as green infrastructure, blue infrastructure, white/grey infrastructure and urban design. The scope of urban functions and requirements, related to urban lives and urban operation, in ten aspects including economy, policy, ecology, environment, technology, space, urban beauty, practicality, culture, and transportation. The analytical framework was further applied to analyze the co-benefits, conflicts and trade-offs of cooling strategies in ten aspects of urban functions. Furthermore, it was used in environmental functions (e.g. local temperature regulation, stormwater regulation, waste treatment, air quality regulation, pollination, and recreation & aesthetic appreciation) and space functions (e.g. activity venue/entertainment venue, neighborhood vitality, resident satisfaction, space utilization and city identity), respectively. The results reveal that green infrastructure can provide the most aspects of benefits in ten aspects, and also in environmental and space aspect. Green infrastructure was followed by blue infrastructure, urban design and then white/grey infrastructure. Overall, the analytical framework offers a new perspective of the feasibility analysis of urban heat mitigation strategy and provides a reference for urban planners and designers to select proper urban heat mitigation techniques, with possible additional benefits of addressing other urban challenges.
Urban pervious concrete for thermal conditioning in open spaces: an adaptation to the climate change and the urban heat island effect.
Authors: Ulloa F T , Ortega G S , Tenorio J A , Ramos J S , Álvarez S
Published: September 2022

UIA CartujaQanat project is part of a new vision of the urban environment, in which the way of thinking about cities and their spaces is changed, as well as in the interaction of its inhabitants with them. In this new concept of urban space, possible solutions to current and future needs, both social and climatic, must be found, since these environments have the responsibility to contribute to improving the lives of their inhabitants by minimizing the consumption of resources used in it. These solutions are the result of the knowledge gained from experience and tradition together with innovation and research.

The project incorporates passive techniques and bioclimatic solutions adapted to the hot and dry climate of the city of Seville, which is where it is located, trying to create semi-confined open spaces that provide a comfortable environment. The solutions adopted introduced water as a heat transfer fluid that allows these spaces to be tempered. Apart from other solutions such as bioclimatic lattices, we worked on draining pavements that, thanks to their permeability, allow the flow of water and the evaporation of air through their surface.

In this work the study of the use of pervious concrete flooring solutions and their advantages over the use of other materials is developed. Analysing its behaviour in its combination in hybrid pavements with vegetal soils or with fines such as silica sand, as well as other solutions that allow a constructive solution that reduces the temperature of the pavement using the evaporative effect, with minimal maintenance and cost.
Indoor CO2 buffering potential of clay-based building materials
Authors: Roucan S , Mcgregor F , Fabbri A , Perlot-Bascoulès C , Morel J-C
Published: September 2022

To mitigate the anthropogenic greenhouse gas emissions from the operational energy consumption in buildings, increasingly high-performance envelopes are developed. A reduction in indoor air renewal is observed that leads to a higher pollutant concentration in the built environment. Particular attention was given to CO2, an anthropogenic gas that has consequences on the Indoor Air Quality (IAQ) and the health of occupants. Developing a passive regulation system appears to be a promising solution for improving IAQ and reducing the energy consumption of ventilation systems. For that purpose, earth-based materials present interesting characteristics through the presence of clay minerals and their microstructure. In this context, this paper aims at presenting a novel experimental method to assess the CO2 retention potential of natural earth plasters. The method uses a thermogravimetric device (TGA/DSC) associated with a gas mixer and humid air generator. The mass variation resulting from the interaction of the increasing CO2 content could thereby be measured and analysed. Results show the important role of reversibility in the phenomenon: the majority of the captured CO2 being released when the CO2 concentration drops. It also highlights the role of the relative humidity on the retention capacity. As the retention of CO2 is lower when the material is wet, the water molecules may occupy part of the adsorption sites and react themselves with the CO2. This experiment provides the first values and thus evidence of the CO2 retention capacity and passive regulation potential of this material.
Machine learning to predict building energy performance in different climates
Authors: Aruta G , Ascione F , Boettcher O , De Masi R F , Mauro G M , Vanoli G P
Published: September 2022

Digitalization is sweeping the world of buildings. Notably, the use of machine and deep learning techniques to develop buildings’ digital twins is becoming crucial to foster the energy transition of the construction sector and a sustainable urban growth. Digital twins can ensure a user-friendly, fast and reliable prediction of building energy loads and demands, thereby enabling a comprehensive optimization of planning, design and operation. Accordingly, this study investigates machine learning techniques to predict heating loads of a building in Rome (Italy, Mediterranean conditions, “Csa” climate in the Köppen and Geiger classification) and in Berlin (Germany, European backcountry, “Cfb”). Firstly, the real building, located in Benevento, is used to develop the artificial neural networks (ANNs), then implemented in MATLAB® to achieve meta-models of building energy behavior. NARX (nonlinear autoregressive model with exogenous inputs) networks are used and trained based on simulated data, provided by the well-known building simulation tool EnergyPlus using the software DesignBuilder® as interface. The meta-model inputs are related to weather conditions, while the required outputs concern the thermal energy load for space heating. The analysis is performed with reference to annual forecasts of energy demands. In all cases, the ANNs architecture is optimized to achieve the best fitness with EnergyPlus outputs. The results show that machine learning can be a precious and reliable tool to support energy design and operation of different buildings in different climates. Nonetheless, the meta-modeling procedure needs to be properly conducted by experts to set suitable frameworks and hyperparameter values of the ANNs, as well as to achieve a right and comprehensive interpretation of the results.