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Direct and indirect approaches can be employed for estimating the heat flow through components in different application fields. In the building sector, the thermometric method is often applied by professionals for thermal transmittance evaluations. However, miscalculations can derive from inaccurate total heat transfer coefficients, and a consensus regarding the appropriate value to employ remains to be determined. Here, an apparatus was realized for laboratory tests and heat flux measurements were performed following direct and indirect approaches. Data acquired through a common heat flow sensor were compared with those computed through a post-processing based on radiative and convective estimations. The results were affected by the specific correlation adopted for computing the convective coefficients, with the percentage differences ranging from −9.8% to −0.4%. New measurement systems could be designed for automatically computing heat fluxes through indirect approaches, thus providing alternative solutions in the panorama of non-destructive tests for building energy diagnosis.

Noise exposure may cause auditory and extra-auditory effects. School teachers and students are exposed to high noise levels which have an impact on perceptual-cognitive and neurobehavioral aspects. The latter influence teaching conditions and student school performance. A Protocol was defined and parameters to be investigated were identified for acoustic characterization of unoccupied and occupied school environments, assessment of users by means of questionnaires completed by teachers and students, and vocal effort evaluation. Classrooms, laboratories, auditoriums, gymnasiums, common areas, canteens and outdoor areas were analysed in terms of acoustic features and identification of the origin of noise. The Protocol was tested in three kindergartens, three primary schools and three secondary schools placed in Rome, Florence and Perugia. Results of nine case studies are presented, including comparisons of objective and subjective investigations. Generally, the acoustic performances of the spaces under investigation do not meet the requirements of current Italian legislation. In particular, student activity determines high noise levels in laboratories, gymnasiums, and canteens. Students notice that noise mainly causes loss of concentration, fatigue, boredom, and headache. The outcomes of this research will be the starting point to define strategies and solutions for noise control and mitigation in schools and to draft guidelines for the acoustical school design.

This study examined the atmospheric urban heat island (UHI) phenomenon within the city of Rome (Italy) and its effects on building energy demand. Weather data from 2020 and 2022 collected from six meteorological stations were considered. A Geographic Information System (GIS) was used to analyze the landscape, correlating the percentage of impermeable surfaces with UHI intensity values in each area. Dynamic simulations were conducted using different climatic data to estimate the heating and cooling energy demands for two representative residential buildings. The findings revealed significant differences in the climatic conditions between urban and rural areas, primarily due to temperature increases. The UHI intensities reached maximum values of 4.67 °C and 3.54 °C in 2020 and 2022. In urban areas, the UHI has positive effects on the heating energy demand but results in a significant increase in energy demand for cooling. Considering a building type constructed between 1900 and 1950, a variation of up to 33.03% in the heating energy demand in urban areas compared to rural areas was calculated, along with a variation of up to 81% for cooling. In contrast, considering a more recent building type constructed between 1991 and 2005, the corresponding values reached up to 36.47% and 75.7%.

Recent research has been developed by different groups towards the development of sonic crystals as noise barriers. The present paper aims to contribute to this research, focusing on the possible application of this technology in practice, and exploring some aspects that may be useful for its further development. One of the objectives of this work is to explore the differences between experimental results obtained under laboratory conditions and numerical results computed with the finite element method (FEM), in 2D and 3D, understanding if different types of simplified models can be of use in the practical analysis of sonic crystals. Through this comparison, a validation of the prediction numerical models is performed, giving confidence for their use in the development and study of sonic crystal configurations. In this context, different geometric arrangements of the sonic crystals’ scatterers (the individual elements that make up the barriers) have been analyzed with the help of the numerical method, evaluating their behavior in different arrangements of numbers of elements, shape and size. A number of parametric studies are also performed introducing some randomness in the structure (in scatterer size and spacing), and analyzing its effect on the insertion loss provided by the sonic crystal. These contributions can be significantly useful for the development of new solutions, giving important hints about the sensitivity of these structures to possible defects or limitations in their production.

In this work, a Guarded Hot Box (GHB) was employed to evaluate the effects of environmental boundary conditions on the internal surface thermal resistance of a wall. For this purpose, the study was carried out through an experimental setup to measure temperature - surface and ambient - in the two chambers of the GHB and air velocity near the specimen wall in the hot chamber. The experimental analysis together with the analysis of the dimensionless parameters allowed to determine the internal convective coefficient for different air speeds. To evaluate the results obtained with the proposed methodology, some existing correlations for the determination of the convective coefficient were used. Moreover, the measurement of the emissivity of sample surface and baffle, and the determination of the mean radiant absolute temperature allowed to calculate the radiative coefficient. Therefore, the internal surface thermal resistance with different air velocities, given by the combination of convective and radiative heat transfer, was determined, and compared with the value offered by the standard ISO 6946.

Green Houses Gases (GHG) are negatively influencing the climate, increasing the Global Warming (GW) of the planet. Improving the energy performance of buildings is one of the main strategies that have to be adopted as soon as possible. In this contest, “Super Insulation Materials” (SIM) have been recently developed. The paper fits into this framework and investigates the aerogel applications in architecture to enhance energy retrofitting processes, evaluating its performances and economic feasibility. The study identifies different technological scenarios and analyzes their performance and cost application, highlighting the potential (i.e. saving of usable area inside up to 500% comparing with traditional insulators) and the limits of the aerogel (mean global cost that is 45% higher) application as a technological system for the reduction of energy consumption.

The growing attention to sustainability and life cycle issues by European and international policies has recently encouraged the adoption, in the construction sector, of environmental labels able to quantify the impacts on environment associated with the fabrication of several building materials, e.g., their embodied energy and carbon. Within this framework, since walls represent a large percentage of building mass and therefore of embodied impacts, this article collects and analyzes nearly 180 Environmental Products Declarations (EPDs) of wall construction products such as masonry blocks and concrete panels. The data related to the primary energy (renewable and non-renewable) and the global warming potential extracted from the EPDs were compared firstly at the block level (choosing 1 kg as functional unit), enabling designers and manufacturers to understand and reduce the impacts from wall products at the early design stage. As the design progresses, it is therefore necessary to evaluate the environmental impacts related to the entire wall system. For this purpose, this paper proposes a further investigation on some simple wall options having similar thermal performance and superficial mass (the functional unit chosen in this case was equal to 1 m2 with R ≈ 5 m2K/W, Ms ≈ 260 kg/m2). The outcomes showed how the durability of the materials and the potential of disassembly of the wall stratigraphies can play a crucial role in reducing the environmental impact. This paper provides a methodological reference both for manufacturers to reduce impacts and for designers committed to the application of environmental labeling in the design process since they will now be able to compare their products with others.

An extensive and updated review of 223 values about the embodied energy and carbon of building insulation materials, mainly retrieved from 156 Environmental Product Declarations, is proposed with attention to innovative and emerging insulation materials. Comparative analyses were carried out thanks to the adoption of the same functional unit (1 m2 with a thermal resistance of 1m2K/W and a design life span of 50 years) to assess the consistence of reference values and the main sources of variability. The comparison suffers from many uncertainties and variance decomposition was employed to verify the main drivers of variability in the dataset elaborated. Data about traditional insulation materials show the lowest ranges of variation when reported per functional unit while the definition of reference values for innovative and unconventional insulation materials was quite difficult due to the low values found and their high variance. Traditional inorganic insulation materials exhibit competitive embodied impacts (glass wool: 16–31 MJ/FU and 0.6–1.2 kg CO2eq/FU; stone wool: 21–66 MJ/FU and 1.4–4.2 kg CO2eq/FU) if compared with fossil fuel derived (EPS: 44–78 MJ/FU and 1.9–3.5 kg CO2eq/FU) or many emerging super-insulating solutions (aerogel: 251–372 MJ/FU and 11.6–18.7 kg CO2eq/FU). Density is an important variability carrier for glass wool, stone wool, and EPS.

In recent years, experimental tests related to building components through laboratory facilities have relatively matured. The techniques are based on one-dimensional heat transfer by creating a permanent temperature difference over a specimen to control heat fluxes. The three main methods are the Guarded Hot Box (GHB) method, the Calibrated Hot Box (CHB) method, and the Heat-Flow Meter method (HFM). The HFM method is the most widely applied technique for measuring on-site U-values of building components and several scientific works stressed the need for high temperature differences between the environments, suggesting 10 °C or 15 °C. However, temperature stability and high temperature gradients are difficult to obtain, especially for Mediterranean climatic conditions. Starting from this, an experimental study was conducted through a GHB apparatus, setting temperature differences from 2 °C to 20 °C between the hot and cold chambers. Heat flow measurements were performed to compute the thermal conductance of a specimen characterized by a known stratigraphy, thus highlighting the effect of the low thermal gradient on data acquired by the heat flow sensor. It was found that, even for low temperature differences (2 °C) maintained by ensuring stable thermal conditions, the experimental results are comparable with those obtained for higher and usual temperature differences (20 °C).

Building performance is strongly influenced by the performance of their structural parts, consequently affecting annual energy demands. The thermal characterization of building components can be achieved thanks to the knowledge of their internal layers and the thermal properties of each material. Considering existing buildings, technical data may be unidentified and heat transfer phenomena between walls and environments can be influenced by air-conditioning systems and local thermo-fluid dynamic conditions. Moreover, the conversion of an existing building into a Nearly Zero Energy Building (NZEB) requires accurate measurements and simulations compared with Standards suggestions, based on simplified procedures. Therefore, on-site surveys become fundamental. Standards suggestions can help engineers or technicians to define some unknown information related to heat transfer coefficients and thermo-physical properties. Nevertheless, can Standards' suggestions be considered reliable in every situation? This paper tries to answer this question, debating some investigations conducted in the last years and proposing a methodological approach.

Climate change (CC) is predominantly connected to greenhouse gas (GHG) emissions from the construction sector. It is clear how it is necessary to rethink construction materials in order to reduce GHG emissions. Among the various strategies proposed, recent research has investigated the potential of smart materials. This study in particular aims to develop an innovative building component that combines high energy performance with reduced thickness and weight. For this reason, the potential of Phase Change Materials (PCM) in cement-based mixes is investigated, comparing the performance of a traditional mix with two innovative mixes made with the addition of 3% and 7% PCM. This work characterizes the new material, analyzing its mechanical and thermal performance, highlighting how the mix strength decreases as the PCM ratio increases; however, both mixes may be considered suitable for masonry structures and may be classified as M5 and M15. Furthermore, from the analysis of the thermal performance, it emerges that the mix presents good behavior in terms of insulating properties.

The construction sector is one of the most energy-intensive in the industrialized countries. In order to limit climate change emissions throughout the entire life cycle of a building, in addition to reducing energy consumption in the operational phase, attention should also be paid to the embodied energy and CO2 emissions of the building itself. The purpose of this work is to review data on embodied energy and GWP derived from EPDs of different types of windows, to identify the LCA phases, the most impacting materials and processes from an environmental point of view and to perform a critical analysis of the outcomes. The results show a strong dependence on the typology of the frame, with wooden windows having competitive performances: lower average primary energy non-renewable (1123 MJ/FU), higher average primary energy renewable (respectively 817 MJ/FU) and lower global warming potential (54 kgCO2eq/FU). More transparency and standardization in the information conveyed by the program operators is, however, desirable for a better comparability of windows performances. In particular, the inclusion of the operational impact in the EPD is sporadic, but strongly important, since it can be the most impactful phase.

Among the super insulating materials, aerogel has interesting properties: very low thermal conductivity and density, resistance to high temperatures and transparency. It is a rather expensive material, but incentives in the field can improve its economic attractiveness. Starting from this, the thermal behavior of a test building entirely insulated with aerogel panels was investigated through an extended experimental campaign. A dynamic simulation model of a case study building was generated to better comprehend the energy savings obtained through aerogel in terms of energy demand over a whole year. The investigation was completed by computing the carbon and energy payback times of various retrofit strategies through a life cycle assessment approach, as well as by a cost-benefit analysis through a probabilistic financial framework. Compared to conventional insulation materials, aerogel is characterized by a higher energy and carbon payback time, but it guarantees better environmental performance in the whole life cycle. From an economic-financial perspective, the aerogel retrofit is the best in the current tax incentive scenario. However, due to its higher lump-sum investment, aerogel’s net present value is very sensitive to tax deductions, and it is riskier than the best comparable materials in less favorable tax scenarios.

The majority of Italian schools (70%) were built in the absence of any legislation related to energy efficiency, and therefore have very low energy performance due to aging or poor quality of construction. An energy retrofit of this building stock is needed to meet the current European goals on greenhouse gas emission reduction. The retrofit is also needed in order to guarantee adequate comfort levels in indoor spaces and good conditions for learning and educational activities, that are often not reached in poor quality constructions. This work presents the results of an interdisciplinary study related to the energy requalification of a school located in Ostia, near Rome in Italy, built in the 1960s with a steel structure and Eternit infill. The scope of the analysis is to verify the economic and environmental effectiveness of four proposed retrofit interventions concerning the replacement of fixtures and the installation of an insulating coat. The current thermal transmittance of the walls was evaluated through thermofluximetric measurements conducted in situ; dynamic simulations were performed to determine the current energy performance and the energy performances following the four proposed retrofit scenarios. Energy and carbon payback times were evaluated (by means of the life cycle analysis (LCA) approach) and the economic value was determined for each of the four proposed retrofits, using a probabilistic approach. The results show that the replacement of windows is the most convenient intervention from all points of view. The study provides evidence that an assessment of schools’ energy retrofits should include both economic and life cycle aspects.

Green roofs have a thermal insulating effect known since ancient times. In the building sector, green roofs represent a sustainable passive solution to obtain energy savings, both during winter and summer. Moreover, they are a natural barrier against noise pollution, reducing sound reflections, and they contribute to clean air and biodiversity in urban areas. In this research, a roof-lawn system was studied through a long experimental campaign. Heat-flow meters, air and surface temperature sensors were used in two buildings characterized by different surrounding conditions, geometries and orientations. In both case studies, the thermal behaviors of the roof-lawn system were compared with the conventional roofs. In addition, a dynamic simulation model was created in order to quantify the effect of this green system on the heating and cooling energy demands. The roof-lawn showed a high thermal inertia, with no overheating during summer, and a high insulating capacity, involving energy savings during winter, and consequently better indoor thermal conditions.

The research presented in this paper is focused on the definition of a new methodology for evaluating how illuminated crosswalks influence drivers’ behavior when approaching the zebra in nighttime conditions. The proposed methodology is based on in situ speed measurements, and cars’ speed was detected in an urban road segment of the city of Rome with a Telelaser instrument. Vehicles speed profiles are measured in the same road segment both in LED-illuminated conditions and in non-illuminated conditions. Results have shown a promising impact of the LED lighting system on pedestrian safety. In fact, cars’ mean speed decreases by 19.3% at the crosswalk section in illuminated conditions. Moreover, a positive effect on safety, in terms of mean speed reduction (−16.4%), was found even in the absence of pedestrians.

In the building sector, both passive and active systems are essential for achieving a high-energy performance. Considering passive solutions, green roofs represent a sustainable answer, allowing buildings to reach energy savings, and also reducing the collateral effect of the Urban Heat Island (UHI) phenomenon. In this study, a roof-lawn system was investigated by means of an extended measurement campaign, monitoring the heat transfer across the roof. Heat-flow meters and air- and surface-temperature probes were applied in a real building, in order to compare the performance of the roof-lawn system with a conventional roof. This experimental approach was followed to quantify the different thermal behaviors of the building components. Moreover, an equivalent thermal model of the roof-lawn system was studied, in order to obtain the equivalent thermal properties of the roof, useful for setting building models for yearly energy simulations. The roof-lawn system revealed its advantages, showing a higher thermal inertia with no overheating in summertime and a lower thermal transmittance with energy savings in wintertime, and, consequently, better indoor conditions for the occupants of the building.

I materiali acustici di origine vegetale possono rappresentare delle valide alternative sia dal punto di vista prestazionale che ambientale ai materiali sintetici e minerali, ma al momento attuale un esiguo numero di essi è già pronto da essere commercializzato. La presente memoria propone uno stato dell’arte su questa famiglia di materiali, fornendo le caratteristiche di fonoisolamento/assorbimento a partire dai materiali più diffusi fino a quelli meno convenzionali. Tali prodotti sono realizzati dagli scarti delle coltivazioni e delle aziende di trasformazione: ciò comporta un impatto ambientale basso se i materiali sono disponibili localmente e non in conflitto con colture alimentari. ------ Acoustic materials of vegetable origin can be a good alternative to traditional ones both from the technical and environmental point of view but very few of them are technologically mature enough to be commercialized. The present paper reports a state of the art of this family of materials, providing the acoustic characteristics starting from the most widespread and promising products to the unconventional ones. These products are realized using the residuals of the cultivation process or of the processing industry so their environmental impact is very low, if the raw materials are local and are not in contrast with food crops.

Household energy consumption has been increasing in the last decades; the residential sector is responsible for about 40% of the total final energy use in Europe. Energy efficiency measures can both reduce energy needs of buildings and energy-related CO2 emissions. For this reason, in recent years, the European Union has been making efforts to enhance energy saving in buildings by introducing various policies and strategies; in this context, a common methodology was developed to assess and to certify energy performance of buildings. The positive effects obtained by energy efficiency measures need to be verified, but measuring and monitoring building energy performance is time consuming and financially demanding. Alternatively, energy efficiency can also be evaluated by specific indicators based on energy consumption. In this work, a methodology to investigate the level of energy efficiency reached in the Umbria Region (Central Italy) is described, based on data collected by energy certificates. In fact, energy certificates, which are the outcomes of simulation models, represent a useful and available tool to collect data related to the energy use of dwellings. A database of building energy performance was developed, in which about 6500 energy certificates of residential buildings supplied by Umbria region were inserted. On the basis of this data collection, average energy and CO2 indicators related to the building heritage in Umbria were estimated and compared to national and international indicators derived from official sources. Results showed that the adopted methodology in this work can be an alternative method for the evaluation of energy indicators; in fact, the ones calculated considering simulation data were similar to the ones reported in national and international sources. This allowed to validate the adopted methodology and the efficiency of European policies.

From the Piranesi fantastic architectures to the animation movies and video games of the last thirty years, a new design approach has been introduced and developed: the design of the virtual space. Designing the "virtual" means experiencing a multidisciplinary approach where architecture, engineering, and urban planning meet the new horizons of information and communication technology. This study is focused on virtual space, which is an underground city. Mankind have always made and used underground environments: the possibilities of unlimited spaces to potential development, the reduced needs for raw materials for the construction and the protection from outdoor weather are some of the reasons that prompted humans to the realization of underground spaces in the past. These reasons and the availability of innovative technologies could encourage a breakthrough in the realization of new underground environments. A recent example is represented by the Underground City of Montreal (RÉSO). We present the architectural design of a virtual underground city, which is called Arch[ane], and its evaluation. The underground city is modular and the studied module is composed of eight floors with a total depth of 400 m and dimensions of 800 m × 800 m. The study comprises the evaluation of the effect of sunlight on each eight floors of the city. Daylighting simulations were performed considering different cities at different latitudes, days, and hours. The results have shown that the particular design of the underground city with skylights gives significant values of illuminance at a certain depth. Furthermore, the simulation results show how huge can be the potentialities of software to simulate extremely big environments.

Biodiesel is obtained by the process of transesterification of vegetable oils and animal fats and crude glycerol is the main by-product of the biodiesel manufacturing chain. As a result glycerol production has rapidly increased in the last decades. This work focuses on the development and the validation of a process to convert biodiesel-derived glycerol into a fuel for internal combustion engines. In order to obtain a higher conversion efficiency it was necessary to convert crude glycerol to tert-butyl ethers by means of an etherification process that was carried out in the laboratory. Then the obtained glycol-ethers mixture (GEM) was blended with a commercial diesel fuel to improve its thermal efficiency. In this paper a life cycle analysis for these GEM/diesel blends was carried out using a Life Cycle Assessment (LCA) methodology, in order to evaluate the environmental impacts of these new oxy-fuels; from GEM production to GEM use as an additive for diesel fuel. The LCA results highlight that the use of these new oxy-fuels in diesel engines can lead to an effective reduction in terms of greenhouse gases emissions throughout the entire life cycle.

The determination of the thermal properties of a building envelope is fundamental for the correct design of energy efficient constructions. Opaque walls can be easily modeled as parallel and homogeneous layers, being characterized by a monodimensional thermal flux which allows to evaluate the thermal transmittance with analytical models. These procedures are well established and they lead to reliable results; however, it is important to verify the actual performance with in situ thermal transmittance measurements. This analysis is more important when the wall performance is high, being closely linked to economic assessments. The paper presents the results of a measurement campaign of in situ thermal transmittance, performed in some buildings in the Umbria Region (Italy), designed implementing bio-architecture solutions. The analyzed walls were previously monitored with thermographic surveys in order to assess the correct application of the sensors. Results of the investigation show that in situ thermal transmittance measurements and theoretical calculated U-value are not in perfect agreement. The mismatch becomes important for monolithic structures such as walls made of thermal blocks without insulating layers.

The evaluation of the overall performance of a green building is complex, since many construction, energy and environmental aspects have to be considered. The Umbria Region in Italy, through various public tenders, recently funded several residential buildings, innovative in terms of construction quality, green technologies and sustainable solutions, such as natural building materials, integrated sunspaces, PV (photovoltaic) modules and solar collectors, geothermal heat pumps, that had to be adopted to obtain the public contribution. The University of Perugia carried out an extended monitoring of these buildings, in order to verify the actual achievement of design objectives, to certify the real savings in terms of energy and environmental loads and to assess the indoor comfort conditions for occupants. In situ thermal, acoustical and lighting measurements were carried out for more than one year. Energy simulations were performed by means of codes which implement the algorithms required by the Italian Law. Moreover, a comparison between real consumptions and simulated energy requirements was carried out. Finally, the buildings were characterized from the environmental sustainability point of view, using the method adopted by the Umbria Region. This assessment was borrowed from ITACA (Institute for Innovation and Transparency in Government Procurement and Environmental Compatibility) procedure [an Italian procedure similar to Leadership in Energy and Environmental Design (LEED)] and consists of 20 worksheets, one for each different performance indicator, at the aim of carefully describing the environmental quality of the building.

Among solar passive systems integrated in buildings, sunspaces or solar greenhouses represent a very interesting solution. A sunspace is a closed, southbound volume, constituted by transparent surfaces, adjacent to a building, which reduces winter energy demand thanks to the use of solar gains. The effect of a typical solar greenhouse on the energy balance of a building was evaluated during the heating period with two stationary procedures (Method 5000 and EN ISO 13790) and with a dynamic tool (TRNSYS). After the analysis of the greenhouse alone, the behavior of an entire house was simulated; a flat equipped with a sunspace, recently built thanks to public contributions provided by the Umbria Region in Italy to widespread bio-climatic architecture, was used as case-study. Simulations were carried out for the examined flat, both with a steady-state tool and with a dynamic one; the contribution of the sunspace was estimated thanks to the various methods previously mentioned. Finally, the simulated data were satisfactorily compared with the real energy consumptions (natural gas for heating) of the flat; the sunspace allows a reduction of winter energy demand of the flat of about 20%.

This work is aimed at calculating the energy content of the residues from olive oil production. Olive pulp, olive husk and sludge (a mixture of olive pulp and husk) have been analyzed separately. Olive Mill Effluents (OME) are normally a problem for olive mill farms, yet they may be used as feedstock for biomass-fuelled power plants. Nonetheless, OMEs are characterized by a relatively high humidity content and are produced only during the olive season. Thus, OME need a stabilization process to be employed as a solid biofuel throughout the year. The analyses conducted attempt an evaluation of the energy consumption of a three-stage stabilization process: drying, milling and pelletising. The net electrical energy available from OME is then calculated as a difference between gross energy available and energy consumed for stabilization. The gross available electrical energy was calculated based on direct energy conversion of the stabilized feedstock on a small scale direct combustion and Organic Rankine Cycle (ORC) turbine. Results show that OME are suitable for energy production. Approximately 4500 kJ/kg of net electrical energy may be obtained out of olive sludge or olive pulp, while olive husk shows a potential gross energy of 3400 kJ/kg.

A large part of the stock of Italian educational buildings have undertaken energy retrofit interventions, thanks to European funds allocated by complex technical-administrative calls. In these projects, the suggested retrofit strategies are often selected based on the common best practices (considering average energy savings) but are not supported by proper energy investigations. In this paper, Italian school buildings’ stock was analyzed by cluster analysis with the aim of providing a methodology able to identify the best energy retrofit interventions from the perspective of cost-benefit, and to correlate them with the specific characteristics of the educational buildings. This research is based on the analysis of about 80 school buildings located in central Italy and characterized by different features and construction technologies. The refurbished buildings were classified in homogeneous clusters and, for each of them, the most representative building was identified. Furthermore, for each representative building a validating procedure based on dynamic simulations and a comparison with actual energy use was performed. The two buildings thus singled out provide a model that could be developed into a useful tool for Public Administrations to suggest priorities in the planning of new energy retrofits of existing school building stocks.

This paper analyzes the impact of a change in the thermal insulating material on both the energy and environmental performance of a building, evaluated through two different green building assessment methods: Leadership in Energy and Environmental Design (LEED) and Istituto per l’innovazione e Trasparenza degli Appalti e la Compatibilità Ambientale (ITACA). LEED is one of the most qualified rating systems at an international level; it assesses building sustainability thanks to a point-based system where credits are divided into six different categories. One of these is fully related to building materials. The ITACA procedure derives from the international evaluation system Sustainable Building Tool (SBTool), modified according to the Italian context. In the region of Umbria, ITACA certification is composed of 20 technical sheets, which are classified into five macro-areas. The analysis was developed on a residential building located in the central Italy. It was built taking into account the principles of sustainability as far as both structural and technical solutions are concerned. In order to evaluate the influence of thermal insulating material, different configurations of the envelope were considered, replacing the original material (glass wool) with a synthetic one (expanded polystyrene, EPS) and two natural materials (wood fiber and kenaf). The study aims to highlight how the materials characteristics can affect building energy and environmental performance and to point out the different approaches of the analyzed protocols.