The demand for green insulation materials is expected to grow rapidly in the coming years as the building sector moves towards carbon neutrality. Waste-based thermal insulation materials offer a promising area of research that aims to make a significant contribution to energy and resource efficiency while helping the building sector achieve sustainability targets. However, despite the growing interest of researchers, proposed waste-based thermal insulation products are still mostly at an experimental research level, far from ready for the construction market. The study investigates the potential availability of waste materials for use in thermal insulation products, focusing on the Italian context. The objective is to identify available quantities of waste suitable for use in or as insulation products and the possible barriers to their widespread adoption in the construction industry. The methodology starts with an international literature review, followed by an analysis of national waste statistics to verify quantities, and production and/or collection points for each waste. As a result, more than 20 materials are identified as promising for market uptake. The materials are mostly based on early-stage research, thus a lack of comprehensive analysis regarding their performances limits their application in building renovation and highlights the need for further research.

Throughout the past two centuries, human activities have had a profound impact on Earth, leading to the progressive consumption of natural resources, increasing in waste, pollution and alteration of ecosystems. This has induced a well-known climate change phenomenon with significant consequences for humankind and ecosystems. The growth of cities and improved living conditions will lead to increased consumption of resources, many of which are already expected to run out by the middle of the next decade. It is essential to monitor resource consumption using relevant indicators to drive economic growth toward resources decoupling. Starting from an analysis of the consumption of the four major categories of natural resources, biomass, fossil fuels, non-metallic minerals and metal ores on an international scale, attention is gradually turned to consumption at the Italian level, focusing on the consumption of non-metallic minerals for use in construction. Thus, the focus was on the granite mining district of Buddus & ograve;, in Sardinia, the largest producer in Italy. Granite quarries, which have been drastically reduced in recent decades, have generated huge amounts of processing waste, causing profound changes to landscapes and ecosystems. Based on the analysis of disused quarry sites, the types of rock abandoned have been studied in detail, investigating the chemical-physical, mechanical and technological characteristics and experimenting with innovative products and alternative uses for these wastes. The findings indicate that these residues can be utilised as a secondary raw material within the ceramics industry, also as a protective layer for ventilated facades.

Renewable Energy Communities (REC) offer a promising pathway towards a global energy system transformation. Although EU member states have developed enabling frameworks to accelerate the growth of REC, the consequences of ‘scaling’ energy communities remain under explored. This study asks which aspects of REC are being scaled and how, through a literature review with qualitative content analysis. We develop an indicative mapping of REC scaling and amplification literature categorised by amplification typologies, whether scaling increases impacts within the community, external to the community, or at institutional levels beyond the community. The findings suggest the need for further research in ‘amplifying beyond’: scaling that changes mindsets and values, to unlock the full potential of REC as deep levers of the energy system transformation.

Cities need photovoltaic (PV) systems to meet climate-neutral goals, yet dense urban forms and variable weather limit their output. This review synthesizes how machine learning (ML) models capture both static factors (orientation, roof, and façade geometry) and dynamic drivers (irradiance, transient shading, and meteorology) to predict and optimize urban PV performance. Following PRISMA 2020, we screened 111 records and analyzed 61 peer-reviewed studies (2020–2025), eight Horizon-Europe projects, as well as market reports. Deep learning models—mainly artificial and convolutional neural networks—typically reduce the mean absolute error by 10–30% (median ≈ 15%) compared with physical or empirical baselines, while random forests support transparent feature ranking. Short-term irradiance variability and local shading are the dominant dynamic drivers; roof shape and façade tilt lead the static set. Industry evidence aligns with these findings: ML-enabled inverters and module-level power electronics increase the measured annual yields by about 3–15%. A compact meta-analysis shows a pooled correlation of r ≈ 0.966 (R2 ≈ 0.933; 95% CI 0.961–0.970) and a pooled log error ratio of −0.16 (≈15% relative error reduction), with moderate heterogeneity. Key gaps remain, such as limited data from equatorial megacities, sparse techno-economic or life-cycle metrics, and few validations under heavy soiling. We call for open datasets from multiple cities and climates, and for on-device ML (Tiny Machine Learning) with uncertainty reporting to support bankable, city-scale PV deployment.”

The increasing frequency of extreme heat events poses significant challenges to buildings in terms of escalating thermal stress, while courtyards, as a traditional passive cooling strategy, demonstrate considerable potential in improving building thermal performance and in energy savings for cooling. Although existing studies have revealed the role of courtyards in enhancing their internal microclimate, an in-depth understanding of how design parameters regulate the microclimate and thereby affect the thermal performance of adjacent buildings remains limited, constraining their effective application in coping with extreme heat. This study conducts an exploration of relevant research aiming to elucidate the mechanisms of courtyard microclimate regulation, the quantitative methods employed, and effective design strategies in addressing high temperatures. The findings indicate that courtyards influence the building thermal performance through four mechanisms: solar radiation control, airflow organization, evaporative cooling, and thermal buffering. Their effectiveness depends on the optimized combination of geometry, material properties, and landscape configuration. Moreover, different quantitative methods exhibit notable differences in scale, accuracy, and applicability. Finally, based on the identified key factors and their interactions, this study proposes optimization pathways to bridge the gap between design expectations and practical outcomes, thereby providing both a theoretical framework and practical guidance for advancing the scientific application of courtyards in enhancing building thermal performance and energy efficiency.

As the construction sector is one of the most carbon-intensive and resource-intensive industries, the necessity for a transition from a linear to a circular economy is widely acknowledged. Aimed at facilitating the transition, several policy frameworks, operational tools and assessment instruments have been developed in recent decades. Nevertheless, the integration of circularity in the construction sector remains constrained and haphazard, frequently focusing solely on the production phase and neglecting the comprehensive impacts within the overall process. The detected gap between theoretical framework and practical implementation is reflected by the limited coordination between policies and tools, which creates a significant obstacle to the adoption of consistent and effective practices. A dual analysis is conducted, comprising two parallel domains: an investigation of a circular policy theoretical framework in urban environments through a literature review, and an analysis of practice-oriented tools through resilience assessment and green building rating systems. As a result, common ground and shared targets are identified between the two scopes, as well as contrasts and inconsistencies that require further attention. These are classified according to their role as barriers or drivers of change, and recommendations for synergistic improvement between policies and tools are provided.

Abstract The present study provides both an updated overview of the most recent studies about low environmental impact materials for building retrofitting and meta-analyses of the most important features, such as the thermal conductivity, allowing to evaluate their insulation potential against the diffused and recurrent conventional competitors. Specifically, 466 case studies about materials derived by co-production, wastes of other products and recycled ones have been selected and their thermal performances have been analysed. The materials have been clustered into homogeneous classes: lose materials and foams; structural materials; panels; finishing materials. The results show that some low environmental impact materials are characterized by thermal performances which can position them as materials able to contribute to building decarbonization, but little information can be found about other characteristics which can be crucial when the built environment is considered, such as durability, fire resistance, costs, and load resistance. Yet, these latter aspects may be investigated further when the material is considered to enter the prototyping phase whether in the academic or market context. The present study provides a base for discussion about the use of more environmentally friendly thermal insulation materials which in the coming years might represent a valid option for sustainable building renovation.

Energy poverty is a significant social, economic, and health issue which increasingly affects millions of households worldwide. Both climate change and the socio-economic crisis have aggravated this phenomenon, making families unable to keep adequate comfort conditions at home because of economic constraints and/or dwelling inefficiencies. Considering the recent inflation trends, as well as the global effort to reduce the building sector’s carbon emissions, energy retrofitting of buildings emerges as the most forward-looking strategy to cope with energy poverty risk. In the case of large building stocks, which are typical for social housing complexes across the EU, deep and fast energy retrofitting might prove challenging, especially considering the resource shortages and disruptions to occupants that may arise. Therefore, this article investigates the relationship between the envelope’s insulation ratio and the risk of energy poverty for households. To this end, diverse scenarios are defined, corresponding to progressive increases in the percentage of building envelope that is insulated. The resulting energy needs are calculated for each of them and correlated with local average incomes and relative energy expenses of households. This is tested on an Italian social housing demo case. The results confirm a predictable but not linear correlation between thermal insulation and reduced energy needs for heating, and an interesting side effect on cooling needs for scenarios that perform better in winter. As for income, energy cost has a greater effect on the energy poverty risk when monthly rent is lower, while energy prices have a major role when rent per month is higher.

Forecasts of a drastic increase in temperatures in the coming decades are driving the adoption of design strategies and solutions to improve the livability of urban environments. Increasing attention is being paid to the thermal comfort of open spaces by both designers and researchers. Nature-based solutions and man-made devices to improve the comfort of outdoor spaces during summer are spreading, but effective, easy simulation and design support tools for this purpose are still lacking, as most of the available software such as ENVI-met or RayMan cannot model such devices. As Physiological Equivalent Temperature (PET) is one of the most relevant and comprehensive indicators of Outdoor Thermal Comfort (OTC), this study aims to investigate PET variations of different artificial shading systems and propose a simplified methodology for assessing them through analytical simulations with RayMan software. When modeling the shading elements, the trick adopted for this purpose is to associate different cloud densities with the shading provided by the screens, thus overcoming a gap that affects the software. The procedure is digitally tested in a covered courtyard case study in Bologna (Italy). Diverse options proposed by the designers for textile screening materials have been compared, showing that these reduce by at least 1 °C the PET-gauged thermal stress. Beyond specific results, the main outcome of this study is the procedure developed to simulate sun-shading sail effects on OTC by means of RayMan, which can support designers in planning effective solutions for open space livability in summertime.

Housing plays a key role in the world path to energy transition, and retrofitting buildings is a major asset to this end. Unfortunately, despite the supporting measures and incentives promoted in many countries, the renovation rate is still too slow. This is even more complex within some specific assets, such as social housing, which, especially in Italy, depends on the availability of public funds. The study proposes a predictive tool conceived as an enabler in the decision-making process, capable of considering and comparing the performance levels that different retrofitting actions can reach, according to building features, intervention costs, timing, and resource availability. The tool is tested on a social housing case study in Bologna.

In the last decades, significant effort has been put towards technological advancement in housing for energy transition. Massive retrofitting actions have been called for, and innovative technologies for smart energy management at home have been deployed. However, undesired energy trends in housing suggest that relevant factors have been neglected. Among these, increasing importance is now given to occupants’ behaviour, and their capacity to interact with energy management devices available in dwellings. This study investigates what is the position of next-generation users on energy transition at home. Two years ago, the authors launched a survey to explore people’s awareness of energy use practices, interaction with metering devices, and user motivation to change when informed. As a pilot survey, over 300 people from the academy were involved to see what was the position of a sample which was supposed to be informed more than the average, in Italy. The test yielded early outcomes on how people become more interested to change as they gain knowledge and are offered suggestions. Despite the expectations, the sample’s level of awareness was low. This suggested that a more user-centred approach is needed for wide-scale progress. Especially results from the youngest were below prospects. The questionnaire was relaunched to examine if the pandemic, energy crisis and latest news on climate change have affected positions of the youngsters. A testing session involving university students was performed, and results have been compared with the previous. As a result, reflections on the energy use patterns of the next-generation households are provided.

The COVID-19 pandemic has amplified a crisis that has already been underway for at least a decade: to stimulate recovery, the EU has put in place an impressive package of measures, the implementation of which is largely left to the national authorities. This would require a systematic reading of the territory, which in Italy clashes with the chronic lack of effective paths to interconnect the political levels to the decision-making processes at different scales. This article presents a method for mapping the relationships between the main environmental challenges and the response (individual and collective) that the community, if enabled, is able to offer in terms of adapting its behaviour. The method consists of a matrix of relationships between environmental priorities and behavioural models.

The improvement of the digital infrastructure envisaged by the National Recovery and Resilience Plan (PNRR) promises new opportunities for reducing energy consumption based on user behaviour for the residential sector. Smart tools for energy monitoring would make it possible to improve indoor comfort, limit household expenses and reduce their environmental impact, with particularly appreciable effects in social housing. However, the diffusion of these technologies, which are already available on the market, largely depends on the ability of users to actively interact with them and on the understanding of their advantages. The study investigates the interaction of users with the typical system and equipment of social housing, comparing the opinion of the inhabitants with instrumental monitoring on a pilot case in Bologna, in order to define the characteristics of an integrative tool to inform the user and suggest good energy use practices.

Designing sustainable and, at the same moment, resilient buildings is a necessity to reach the UN Sustainable Development Goals by 2030. However, these two building design approaches - sustainability and resilience - are usually treated separately. Typically, resilience-improving strategies are placed only after a disruptive event and not at the design stage. It is clear that there is a substantial intersection between sustainability and resilience and this manuscript aims to determine more precisely the commonalities and contradictions seen in building design sustainable and resilient approaches as crucial elements for improving their cooperation in buildings. To accomplish this, the authors qualitatively analysed two case studies - respectively claiming to be sustainable and resilient - to understand if a sustainable building can also be considered resilient and vice versa. This paper is addressed to the private and public sectors that have a decisive role in building design and are determined to take tangible steps to influence decision-making and resilience-based solutions already at the design phase. In conclusion, once the commonalities of resilience and sustainability are highlighted, a building designed as sustainable or resilient will be in line with both long-term perspectives.

Retrofitting the built environment is crucial for the achievement of the global sustainable development targets. Therefore, several measures, strategies, and technologies have been developed to pursue this aim and reduce the energy demand of existing buildings. Within this framework, the EU social housing stock represents a relatively small but critical and peculiar share to handle, as the involved variety of economic, social, and environmental issues makes any intervention tough and tricky. This is particularly true in Italy, where about seventy local agencies, which manage over 1 million publicly owned housing assets, are struggling with a shortage of funds to invest and a lack of adequate knowledge of the conditions of their assets. The research we carried out aims at providing managers of large housing parks with a digital tool useful for rapidly forecasting the effects of different refurbishment scenarios. This should allow planning maintenance interventions effectively, according to the available resources. The main result of the study is an algorithm that powers a predictive diagnostic tool by which the current energy behaviour of buildings can be estimated and the effects of different energy retrofitting measures on their overall performance can be simulated.

The responsibilities of the building sector concerning resource consumption and waste generation, as a problem of research, require a transition from a linear to a circular model in order to obtain significant positive effects on the environment. The Biomimicry approach appears to be a promising way to move the sector towards the circular economy, to meet the increasing levels of functional and environmental requirements, which is shifting the research on building materials and products toward biomimetic solutions. Along this path, the building envelope emerges as an interesting application field concerning its adaptive behaviour towards external conditions. In this field of research, the knowledge gap concerns the need for criteria to classify the biomimetic behaviour of building materials under operating conditions and to identify their environmental effects, as well as their compliance with the principles of the circular economy. The study provides a methodology to develop a set of classification criteria applicable to biomimetic materials and products which are suitable for application in the building envelope and a related set of markers that identify the strongest environmental relationships and implications related to the aptitude for integrating circular economy principles. The mapping highlights the absence of some relationships thus highlighting potential limitations of biomimetic materials/products within circular economy principles and thus current research limits. The results obtained may be useful to evaluate and compare biomimetic materials and products for the building envelope, whilst also providing the first step for further research on their environmental implications within circular economy processes.

For a long time, the design of factories has been profit-driven only, while their detrimental effects on the environment, perceptual-aesthetic interferences with the surroundings, and social disturbances on local communities have been largely neglected. Despite a growing attention towards these topics, literature shows that there is a fundamental knowledge and tool gap on design practices for holistically sustainable factories, and companies are often unaware of both negative and positive effects related to the impact of their sites on the landscape. This paper presents a toolkit that has been developed to support entrepreneurs and designers in devising more sustainable factories through an integrated perspective, which is the great novelty of the approach. The article focuses on one of its tools: a digital atlas of design tactics. These have been mapped in sustainable factories around the world and labelled with an ad hoc faceted classification. Each tactic is then described in an info-sheet, which feeds a web portal. There, the user is assisted in searching for the most suitable tactics and mutual links with other useful strategies. The main potentiality of the atlas is to encourage a holistic design approach by highlighting positive synergies among tactics from different fields.

Housing is the main environmental impact generator (62 %) of the whole building sector, but it also has the greatest reduction potential. Enhancing its performance is thus crucial to sustainable development. Social Housing (SH) represents a critical asset within the residential segment, due to the recurrent investment shortage and several environmental, social, and economic related implications. In Italy, SH is held by around one hundred public agencies facing endemic resource constraints for both maintenance and retrofitting, which are limited further by a diffused lack of information regarding the conditions and features of the buildings they manage. In cooperation with an Italian SH agency (ACER Bologna), we developed a speedy tool to compare the technical and economic effects of different refurbishment scenarios on a case-by-case basis. This is not a tool to manage retrofitting works, as the many already available, but a means to help large housing managers overcome the intention-action gap that limit their capacity to properly prioritize interventions based on reliable information. The research focuses on the validation of the fast procedure for estimating the baseline energy scenario, arguing that the relatively small inaccuracies are irrelevant for the scope of the tool and are compensated for by the time saved.

Green Building Rating Systems (GBRSs) are typically third-party, voluntary, and market driven standards that measure buildings’ sustainability level by multi-criteria assessment, and encourage the adoption of environmentally, socially and economically sustainable practices in design, construction and operation of buildings (or neighborhoods). GBRSs aim at guiding and assessing the project throughout all its life cycle, thus limiting the negative impact on the environment, as well as on the building occupants’ health and well-being, and even reducing operational costs. Hundreds of GBRSs are now available worldwide, varying in approaches, application processes, and evaluation metrics. BREEAM, CASBEE, Green Star and LEED are among the most applied worldwide. Despite some differences, they all adhere to the same general evaluation structure: project performances ares measured using a set of relevant indicators, grouped per topics such as water management, energy use, materials, site qualities. Each assessed requirement is assigned a score/judgment, the total of which determines the level of sustainability achieved. In addition to regular updates, a current trend is to improve the effectiveness of protocols, making them more comprehensive and accurate, while keeping them easy to use.