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Transparent elements of buildings account for most of the variation in the spectrum of transmitted daylight. This behavior has a considerable impact on the luminous quality of the indoor environment, because the light spectral composition affects the perceived color and brightness of the illuminated objects. As a consequence, the effect of light colour and intensity on the behavior and health of the occupants is very important. Among the innovative transparent solutions for buildings, monolithic aerogel is one of the most promising, both in terms of lighting and thermal performance. In this context, the present study investigates the colour rendering properties of monolithic aerogel. For the analysis we employed a machine vision system based on a dome-shape illuminator, a digital camera, a chroma meter, and a colour checker. We evaluated the effect of the aerogel on colour rendering by measuring the RGB and CIE Lab coordinates of the reference colours of the colour checker with and without the aerogel. The results show that, in general, the presence of aerogel tends to shift all the colours towards a blue hue, the maximum variations occurring with dark tones of red, yellow, and green. Finally the Colour Rendering Index Ra was calculated for the examined monolithic aerogel by means of a methodology developed in accordance to the EN ISO 410 standard and CIE standard procedures. The obtained values prove a rather good visual quality of the monolithic aerogel (Ra = 85).

This paper investigates the influence of adding vegetal fibers on thermal and acoustic performance based on natural hydraulic lime. Mortar samples with 10% weight of vegetal fibers were fabricated adding water to obtain easily workable mortars with good consistency; their performance was compared to mortar samples without vegetal fibers. The fibers were of different types (rice husk, spelt bran, and Khorasan (turanicum) wheat chaff) and size (as-found and ground form). Thermal performance was measured with the Small Hot Box experimental apparatus. Thermal conductivity was reduced in the 1–11% range (with Khorasan wheat chaff and rice husk); no significant reduction was found with spelled bran in the mixture. When ground, fibers were characterized by both good thermal and acoustic absorption performance; a reduction of 6–22% in thermal conductivity λ was achieved with spelled bran (λ = 0.64 W/mK) and rice husks (λ = 0.53 W/mK), whereas the Khorasan wheat chaff had the highest sound absorption average index (0.38). However, the addition of fibers reduced sound insulation properties due to their low weight densities. This reduction was limited for rice husks (transmission loss value was only 2 dB lower than the reference).

This study aims to investigate the thermo-acoustic and hygrothermal properties of innovative panels made of leather waste produced by a bag factory from a circular economy perspective. Their performance was compared with other residual-based insulation panels. The leather scraps were chipped and three boards were fabricated by means of a mold with different compositions, adding adhesive glue. In order to improve the sustainability aspects, a sample was assembled by using a water-based polyurethane glue, in addition to the two panels with vinyl glue. Panels were tested for thermal, acoustic, and hygrothermal performance. Thermal conductivity values in the range of 0.064–0.078 W/mK at 10 °C were measured depending on the composition and the adhesive. A slight thermal performance deterioration occurs when using the natural water-based glue. The samples were characterized by good performance both in terms of sound absorption coefficient (Noise Reduction Coefficient NRC = 0.21–0.28) and Transmission Loss, up to 59 dB values. Water vapor resistance factor values in the 35–48 range were obtained, close to the values of standard materials, such as expanded polystyrene and polyurethane.

Multiple high quality wood waste from a window manufacturer is identified and collected. Eco-sustainable panels, with promising acoustic and thermal insulating performance, were then fabricated. The available wood is of different tree species (pine, oak, and mahogany) and size (pieces of wood, mixed coarse chips, and mixed fine chips). Moreover, scraps of olive tree pruning from local areas were collected for reuse. The aim of the research is to assembly panels (300 × 300 mm2) both with different techniques (hand-made and hot-pressed) and type of adhesive (vinyl and flour glues) and to evaluate their thermal, acoustic, and environmental performance. All the panels present thermal and acoustic performance comparable with the similar ones available in the literature or with commercial solutions. The thermal conductivity varies in the 0.071 to 0.084 W/mK range at an average temperature of 10 °C, depending on the tree species, the assembly technique, and regardless of the type of adhesive used. Oak wood panels are characterized by both better sound absorption (α peak value of 0.9, similar to pine pressed sample with flour glue) and insulation (transmission loss up to 11 dB at 1700 Hz) properties. However, their added value is the low environmental impact assessed through life cycle analysis in compliance with ISO 14040, especially for panels assembled with natural glue.

This study evaluated the influence of storage method on the physical and chemical properties of laricio pine wood chips for energy generation in the region of Basilicata, Italy. The storage of wood chips is a key factor in the wood fuel supply chain because it allows to compensate temporal differences between production and consumption stages. Experimental trials were performed analyzing three storage methods of wood chips: uncovered pile, under vapour-permeable and waterproof cover (PP sheet), and under waterproof PVC cover (PVC sheet). During six months of storage (from August 2016 to January 2017), only the wood chips pile covered under PP sheet registered a decrease in moisture content (about -19%). Use of cover made of vapour-permeable material was also found to improve the heating value of biomass (about +15%). However, the ash content was observed to increase throughout the storage period, reaching the maximum value for the uncovered wood chips pile (about +74%). No statistically significant differences between PP and PVC sheets were detected for dry matter losses, while significant energy losses were found in every kind of storage system. As a result of the analyzed weather conditions, open-air uncovered storage is suitable for short-term storage periods (less than 2 months), while for long-term period the use of permeable covers is more profitable.

Aerogel is a promising building envelope material that can be used to improve thermal and lighting performance. In monolithic form, aerogels allow visual interaction between the built and outdoor environments, unlike aerogels in granular form. However, the high production cost of large monoliths limits their use. In this work, monolithic silica aerogels were fabricated using tetramethyl orthosilicate as the precursor in a base-catalysed recipe, and a novel rapid supercritical extraction method. The method produces transparent aerogel monoliths in as little as six hours. A 30 × 30 cm glazing sample was constructed from nine 15-mm-thick aerogel monoliths sandwiched between two pieces of 4.7-mm-thick float glass. The glazing sample was characterized in terms of directional and hemispherical optical and visual properties. Measurements were made with an in-house-constructed spectrophotometer equipped with a 75-cm-diameter integrating sphere in the 380- to 2300- nm wavelength range with variable incidence angles. The light and direct solar transmittance are 0.69 and 0.62, while the light and direct solar reflectance are 0.25 and 0.19, respectively. The sample is also characterized by a high general colour rendering index (Ra = 96), allowing indoor visual comfort. Gonio-photometric and directional spectral transmittance measurements show negligible visual distortion and colour variation at different observation angles. The light transmittance of the prototype is lower than that of glazing units present on the market, but about 10% higher than an equivalent unit with granular aerogel. This performance is promising for applications where view through a window is required. However, the size of the samples currently fabricated with the innovative process is limited to 14 × 14 cm and they are characterized by some optical defects that must be removed if the process is to be used for commercial product.

The building sector is one of the biggest consumers of energy in the world and it is pushing the scientific community to find various alternative solutions to solve the problem of thermal insulation of buildings. Therefore, the selection of appropriate building materials is a major challenge for improving the thermal comfort and energy performance of buildings. In this scenario, the interest of plaster-based composites as insulating materials increases, in particular for new applications, as insulators for the building envelope, and this deserves to be studied. In this investigation, new plaster-based composites with cork were produced and tested at lab scale, in order to obtain cheap solutions with improved thermo-physical and acoustic performance. The results show that it is possible to improve the thermal, mechanical, and acoustic performance of construction biomaterials by using plaster as a binder and cork as a natural reinforcement: thermal conductivity was equal to 0.097 W/m.K, the compressive strength to about 2.30 MPa, and the transmission loss to about 40 dB. Keywords: Plaster-Gypsum; Cork; Thermal, Mechanical and Acoustic Properties.

This paper concerns the development of an automatic tool, based on Fuzzy Logic, which is able to identify the proper solutions for the energy retrofitting of existing buildings. Regarding winter heating, opaque and glazing surfaces are considered in order to reduce building heat dispersions. Starting from energy diagnosis, it is possible to formulate retrofitting proposals and to evaluate the effectiveness of the intervention considering several aspects (energy savings, costs, intervention typology). The innovation of this work is represented by the application of a fuzzy logic expert system to obtain an indication about the proper interventions for building energy retrofitting, providing as inputs only few parameters, with a strong reduction in time and effort with respect to the software tools and methodologies currently applied by experts. The novelty of the paper is the easy handling properties of the developed tool, which requires only a few data about the buildings: not many such methods were developed in the last years. The energy requirements for winter heating before and after particular interventions were evaluated for a consistent set of buildings in order to produce the required knowledge base for the tool’s development. The identified appropriate inputs and outputs, their domains of discretization, the membership functions associated to each fuzzy set, and the linguistic rules were deduced on the basis of the knowledge determined in this was. Therefore, the system was successfully validated with reference to further buildings characterized by different design and architecture features, showing a good agreement with the intervention opportunities evaluated.

Livestock production as a contributing factor of global warming has become a critical aspect of policy development among scientists, institutions, governments, and societies. Improving the animal farms performance in the several countries is a key strategy to meet the demand for animal protein, reducing greenhouse gas emissions, and improving resource use efficiency. In this context, this chapter presents a global overview of beef production systems, their diversity, the way they can contribute to major global environmental issues and the evaluation of specific points for intervention. The characteristics of the beef production systems all over the world are analyzed, together with the goal and scope, the types of analysis (methods for the evaluation of the carbon footprint), the functional units generally implemented for the analyses, the allocation methods, and the uncertainties of the studies. This detailed overview allows a critical analysis of the selected studies, which are discussed in the last section of the chapter. It was found that it is important to improve the understanding of biological processes involved in the emissions of methane and nitrous oxide processes, in order to obtain more valid and reliable carbon footprint results.

In the recent past, great attention has been posed on the assessment of the energy performance and of the operating and maintenance costs of the building stock. Currently, new approaches of analysis are considered by the scientific community, which put the occupant's well–being at the centre of the evaluation process. In this context, the IEQ assessment acquires an ever increasing importance, especially if the combined effects of multiple environmental factors are considered. With this purpose, to date, different weighting schemes can be found in the literature, obtained through subjective investigations and mathematical methods. In this paper, the weighting schemes proposed in the literature in the period 2002–2018 were examined, considering the survey methodologies used. The more relevant studies found in the literature were compared and the related weighting schemes were discussed, based on the intended use of the buildings. In particular, 122,000 questionnaires in 18 different countries all over the world were examined and the most relevant environmental factors were selected: Thermal Environment (TH), Air Quality (AQ), Acoustics (AC), and Lighting (LT). Three different average weighting schemes were obtained for each of the following uses: offices, schools, dwellings; a final additional weighting scheme was obtained considering the average values of the normalized weights for all the building uses, a possible solution for buildings with an unspecified or not unique intended use. Moreover, an original weighting scheme was obtained and proposed on the basis of the results of three different subjective surveys, involving about 1400 participants, carried out in some university classrooms at the School of Engineering of the University of Pisa: it was compared with the one obtained by the literature for school buildings. It was observed an overestimation of the importance of TH (0.42 instead of 0.33) and an underestimation of AC (0.19 instead of 0.26), whereas AQ and LT are in accordance (0.17 instead of 0.19 and 0.22, respectively). The results of the present study can be useful to those who intend to deal with holistic approaches to building design, for which accurate assessments of occupants’ well-being are taken into consideration as well as aspects related to energy performance and building management costs.

A comprehensive review of aerogel glazing systems is provided, focusing on the main properties of interest in building applications. Both granular and monolithic forms are taken into account, even if only the former is available on the market. Reviewed studies regard the material itself and of the assembled glazing systems are analysed. After a short description of the fabrication process, thermal and optical properties are presented, in order to provide a set of useful data on the most important parameters affecting energy and lighting performance of buildings. Not-energy related aspects, as quality of lighting and acoustic properties are also investigated, being relevant for the successful building integration. Numerical analyses and field studies show the potential of the technology to achieve relevant energy savings with respect to conventional glazing systems, especially in cold dominated climates. Long term performance studies confirm the reliability of the technology, with minor functionality issues to be solved. Costs of aerogel are still considerably higher when compared to conventional glazing units, however the fully developed technology may become competitive with the performance required in a zero energy building perspective.

The excellent thermal insulation properties of aerogel glazing systems make them an interesting building solution, especially in cold climates. When aerogel glazing systems provide less solar heat gain factor, they could be useful in warm and hot regions (such as Tokyo, Rome and so on) because buildings in such areas are often designed to minimize cooling energy demands. If a sort of opaque powder is mixed with aerogel granules, able to stick to each granule and to cover the aerogel surface discontinuously, the mixture can thus reduce solar transmittance, contributing to daylight usage with less glare risks and cooling energy demand reduction, without shade or blinds, keeping as high thermal performance as aerogel. This innovation is examined in the present paper, by presenting the following solution: a double glazing unit with a mixture of silica granular aerogel and hollow silica powder in the gap (AGS), in order to reduce the solar factor. The solution is tested through in-field experimental campaigns and numerical analyses, making available a set of data not found in literature, where mixtures of aerogel and powder were never studied. The air temperatures in the test Room with AGS, especially the peak values, are lower than the ones in the reference one with installed a standard glazing system (SGS). The same behaviour is observed in several experimental campaigns in different seasons: in mid-season 1 the highest differences are of about 6–7 °C, whereas in summer they reach 12–16 °C. Significant differences in terms of illuminance are also observed: the calculated Useful Daylight Illuminance (UDI) shows AGS values 57% higher than SGS, highlighting the aerogel ability to diffuse light and to reduce glare. Experimental data were used for energy analyses of a reference building in Tokyo. AGS outperforms a low-e glazing in terms of heating energy demand: the reduction varies in the 22% (North) − 62% (South) range. The lighting energy demand is quite similar: electricity demand increases in the 3–6% range. Finally, the internal shade on the reference glazing has a significant impact on the estimated energy demand, both for cooling and heating.

In order to reduce the heat loss from envelopes and to ensure energy saving in building refurbishment, polystyrene balls are added to Moroccan natural gypsum plaster. A complete characterization of the mechanical, thermal, and acoustic properties of the samples is carried out, taking into account different contents and diameters of the polystyrene balls. Increasing balls size, flexural strength peak value occurred with a lower polystyrene percentage. Thermal properties were measured by means of Small Hot Box apparatus. The values of conductivity were 0.191 and 0.116 W/mK for 10% and 30% addition of the smallest polystyrene balls, respectively. The acoustic properties were measured by means of a Kundt’s Tube, in terms of absorption coefficient and sound insulation. The absorption coefficients were slightly higher than the ones of standard plasters. As concerning insulation properties, a worse performance was expected, due to the lower density of the samples with the balls, according to the Mass Low. Anyway the transmission loss values were up to 45 dB, with a reduction of only 2–3 dB with respect to the samples without balls, showing a good performance for the proposed composites. Finally, dynamic energy simulations for a case study showed that polystyrene plaster with smaller balls applied on the wall surfaces of a residential building involved benefits both for heating and cooling energy demand. A small thickness (3 cm) of insulating material could be a suitable solution in order to enhance the thermal and acoustic performance and to reduce environmental impact of the construction systems.

Climate change and global warming issues are becoming more and more important nowadays: the atmospheric concentration of carbon dioxide has been significantly increasing since the twentieth century, mainly due to energy use and anthropogenic activities [...]

The work was developed in the ReScaLe FiAer project framework, funded by the Fondazione Cassa di Risparmio di Perugia. It is focused on the identification and collection of multiple high quality wood waste from a local window manufacturer. Three types of wood were available, from different tree species (pine, oak, and mahogany) and sizes (pieces of wood, mixed coarse chips, and mixed fine chips). Preliminary analyses were performed in order to evaluate the properties of the raw material. For each type of wood, eco-sustainable panels (300x300 mm2) were assembled by gluing. Multiple tests were carried out in order to identify the optimal mixtures and to ensure a good mechanical resistance with the minimum adhesive use. Panels were assembled by using vinyl glue, easily available and cheap, and flour glue, with a lower environmental impact and safe for people’s health. The thermal conductivity of the panels was measured by means of the Small Hot Box experimental apparatus: it varies in the 0.071-0.084 W/mK range, at an average temperature of 10°C, depending on the tree species and regardless of the type of adhesive used. Furthermore, 100-mm diameter cylindrical samples with two different thicknesses for each type of wood and glue were fabricated, in order to investigate their acoustic behaviour in an impedance tube. The use of flour glue improves the sound absorption and insulation performance of the samples.

Nowadays, the belief that lighting can influence comfort, productivity and people's health is well established. In educational rooms the absence of adequate levels of indoor comfort can greatly influence the learning ability of students. The evaluation of lighting indoor quality is often limited to test and check the illuminance levels of the main tasks. However, the lighting quality and the achievement of adequate levels of visual comfort strongly depend on other factors that cannot be overlooked in a detailed analysis. The authors propose an original lighting quality assessment method for the evaluation of lighting in educational rooms, aimed at analysing all the main aspects and at defining a ranking of the critical issues, in order to consider improvements. The method based on the selection of lighting criteria, sub-criteria, and related indicators. Since an analytic hierarchy process was applied to assign a weight to each criterion that has a different impact on the lighting quality. The proposed method was applied at the scale of the single classroom and of a group consisting of six classrooms, considering the buildings of the School of Engineering at University of Pisa as case study. Finally, with the aim of verifying the correspondence between results of the proposed method and actual users' perception, a subjective survey was carried out in the same investigated classrooms. A total of 420 questionnaires were filled, and the results revealed the correspondence between the proposed method and the subjective surveys, proving the validity of the method.

This study investigates the possibility to reuse finished leather scraps, produced by the leather goods industry during the cutting phase, for the preparation of innovative panels for thermal-noise building insulation. Experimental panels were prepared by chipping the leather cuttings, using polyvinylacetate binder, and pressing the paste in a mold through a mechanical press. Boards were tested for thermal and acoustic performance, thermal stability, hygrothermal, wettability and ignitability properties. Acoustic measurements by means of a Kundt’s tube, and thermal characterization by means of a small hot–box system were performed. The measured thermal conductivity was 0.104 W/(mK) and 0.108 W/(mK) for the 45 °C and 50 °C set-up hot temperatures, respectively. Concerning the acoustic performance, two panels with thickness of 18-mm and 28-mm were produced: they were characterized by a noise reduction coefficient of 0.46 and 0.20 and transmission loss values in the range of 25–33 dB and 25–42 dB, respectively. Results revealed that the leather cutting waste panels were characterized by interesting thermal and acoustic performance, which are of the same order of magnitude of other residual-based insulation panels. The other analyzed properties confirmed the potential application in building insulation.

Biomass is a fundamental renewable resource to develop sustainable energy conversion systems with low environmental impact. The design of biomass pyrolysis, gasification, and combustion facilities requires a particular attention at kinetic aspects. A coffee production residue such as coffee silver skin, which is the main product of the coffee roasting industry, is very suitable for thermochemical conversion, being already dry and containing compounds like the ochratoxin which does not allow its use in the production of biochemicals. In this work, thermal degradation tests of coffee silver skin are made under inert conditions at various heating rates (5, 7, 10, 15 °C/min) and a proper kinetic model was considered in order to quantify the activation energy (Eα). The variation of Eα with the conversion rate (α) was higher than 30%, showing that the process is kinetically complex and the kinetics cannot be described by a single-step model, according to the International Confederation on Thermal Analysis and Calorimetry. For this reason, a multi-step model and an analytical approach were used. This involves the deconvolution of the individual peaks of each pseudo-component from the overall differential kinetic curves, followed by the application of a model free-isoconversional method to the separated decomposition steps. The determination of the reaction mechanism f(α) of each sub-component (pseudo-cellulose P-CL, pseudo-hemicellulose P-HC, and pseudo-lignin P-LG) was performed by using both the Master-Plots method and the Energy Compensation Effect. The pre-exponential factor, the enthalpy and the Gibbs free energy were also evaluated in order to investigate the pyrolysis characteristics. A second order model mechanism was obtained for P-CL and P-HC, whereas no clear mechanism was found for P-LG when α > 0.5.

Indoor comfort, energy demand, carbon emissions and the cost of maintaining a building vary according to the structure of the building and the behaviour of its occupants. The main goal of this research is to analyse the bioclimatic potential of different Malagasy climatic zones. In addition, this study analyses and compares energy consumption and carbon emissions in six building categories commonly found in Sub Sahara African cities designed to be placed in thirteen cities unequally distributed in the six climatic regions in Madagascar. To reach this objective, hourly weather data for the last thirty years were analysed for two seasons. At the same time, the adaptive comfort model defined by the ASHRAE 55 served as a reference for the evaluation of different passive design potentials. The results showed that in the sub-Saharan or hot zone, the range of comfort varies according to with the geographical position and that the number of hours of thermal comfort and acceptability is in the majority of the cases outside the range recommended in the international standards (CIBSE, ASHRAE and ISO). Finally, it was concluded that Madagascar Island, such as other countries, should build their own standard due to the average demand for cooling energy increases every year up to 3.4% in the coastal towns and more than 80% of carbon emissions can be reduced in hospitals in Madagascar, as well as in Sub-Saharan Africa, by increasing the maintenance cost between 7% and 10% of the total life cycle cost of a building. In Madagascar Island, the building Life cycle cost ranges from 12% to 14% for the construction cost, 0–1% for the renovation cost, 36%–73% for the energy cost, 2%–3% for the maintenance cost on the whole LCC.

The mean age of air (MAA) is one of the most useful parameters in evaluating indoor air quality in natural ventilated buildings. Its evaluation is generally based on the CO2 monitoring within the environment, however, other methods can be found in the literature, but they have not always led to satisfactory results. In this context, the present paper is focused on two main topics: the effect of the windows airtightness and of the environmental conditions on MAA and the application of artificial neural network (ANN) for the CO2 prediction within the room. Two case studies (case study 1 located in Terni and case study 2 located in Perugia) were investigated, which differ in geometric dimensions (useful area, volume, window area) and in airtightness of windows. The indoor and outdoor environmental conditions (air temperature, pressure, relative humidity, air velocity, and indoor CO2 concentration) were monitored in 33 experimental campaigns, in four room configurations: open door-open window (OD-OW), closed door-open window (CD-OW), open door-closed window (OD-CW), closed door-closed window (CD-CW). Tracer decay methodology, according to ISO 16000-8:2007 standard, was compiled during all the experimental campaigns. A feedforward ANN, able to simulate the indoor CO2 concentration within the rooms, was then implemented, the monitored environmental conditions (air temperature, pressure, relative humidity, and air velocity), the geometric dimensions (useful area, volume, window area), and the airtightness of windows were provided as input data, while the CO2 concentration was used as target. In particular, data of 19 experimental campaigns were provided for the training process of the network, while 14 were only used for testing the reliability of ANN. The CO2 concentration predicted by ANN was then used for the MAA calculation in the four room configurations. Experimental results show that MAA of case study 2 is always higher, in all the examined configurations, due to the higher airtightness characteristics of the window and to the higher volume of the room. When the difference between indoor and outdoor temperature increases, the MAA increases too, in almost all the investigated configurations. Finally, the CO2 concentration predicted by ANN was compared with experimental data, results show a good accuracy of the network both in CO2 prediction and in the MAA calculation. The predicted CO2 concentration at the beginning of experimental campaigns (time step 0) always differs less than 2% from experimental data, while a mean percentage difference of &minus, 18.8% was found considering the maximum CO2 concentration. The MAA calculated using the predicted CO2 of ANN was greater than the one obtained from experimental data, with a difference in the 0.5&ndash, 1.3 min range, depending on the configuration. According to the results, the developed ANN can be considered an alternative and valuable tool for a preliminary evaluation of MAA.

In order to reduce the carbon emissions resulting from buildings construction, some non-conventional materials are emerging, especially the ones of natural origin. In this scenario new building components have been developed as thermal insulating panels such as the ones made of wood, straw, and cork. In the present paper a multi-sheet wall was investigated by analyzing the thermal properties of each layer by means of a new experimental apparatus named Small Hot-Box. The wall is composed from the outside towards the inside by a ‘cocciopesto’ mortar, a thick layer of straw, a wooden planking, an air interspace of about 5 cm, and a final raw earth plaster, for a total thickness of about 50 cm. Results showed thermal conductivities in accordance to Literature values both for the wood (0.089 W/mK) and for the straw (0.065 W/mK). For the ‘cocciopesto’ and the earth-based plasters no many Literature data are available: the thermal conductivities are equal to 0.92 and 0.98 W/mK respectively. The total thermal transmittance of the wall was estimated by combining the results and considering the real scale thickness of each layer; it is about 0.15 W/m2K.

Students spend a lot of time at school, highlighting the great importance of providing comfortable conditions in educational buildings. Indoor environmental conditions are also related to student productivity and well-being, but Literature reviews mainly examine the effects of single parameters on human comfort, lacking in the evaluation of comfort combining different aspects, such as thermal, acoustic, and visual ones. The aim of the paper is to propose an index for the evaluation of the environmental comfort tacking into account thermal, acoustic, and lighting conditions. Seven university classrooms were investigated; measurements of environmental factors were performed including thermal, acoustic, and lighting parameters. Subjective evaluations were also carried out through survey questionnaires purposely elaborated. Three single indexes were proposed basing on the strongest correlation between questionnaire's answer and experimental results: a Predicted Mean Vote Index for the thermo-hygrometric conditions, a Sound Index for the acoustic comfort, and a Visual Index for the lighting conditions. All the indexes are dimensionless and normalized in a 0–1 range: values next to 1 indicate good comfort conditions and values next to 0 indicate bad comfort conditions. On the basis of different weights given for the three aspects, a final combined comfort index was calculated for each classroom and compared with questionnaires results, in order to assess the methodology.

Ventilated walls were adopted in the past in order to protect buildings from moisture and weathering. Today their main use is for energy purposes. In this paper, a new kind of ventilated wall made of traditional and local materials was studied, with the support of a local brick producer Company. A first prototype of ventilated wall was built between two test chambers at the Laboratory of the Department of Engineering – University of Perugia, and the heat transfer and the velocity profile developed within the air gap were investigated in controlled condition, by considering both unventilated and ventilated configurations obtained opening and closing some ventilation holes. The laboratory experimental campaigns were carried out in steady state, in order to study the air motion field from a fluid-dynamic point of view. The ventilation into the air gap was also investigated by means of CFD simulations; different turbulent models and one radiation heat transfer model were tested and validated with the collected data during the laboratory experimental campaign, in order to check the best solution able to correctly simulate the velocity profile in the masonry wall. The validated CFD model was therefore used for the optimization of the ventilation openings, by studying the velocity profile into the air gap. The best solution was then chosen and a new prototype of the ventilated wall was built in a new school gym; in order to investigate the thermal behavior of the developed wall, an intensive experimental campaign is still in progress.

In building applications, recycled waste materials are becoming promising acoustic absorbers and thermal insulating solutions in order to reduce the environmental impact. The aim of the research is to evaluate the thermal, acoustic, and environmental performance of recycled waste panels consisting of rice husk (RH) produced by gluing and pressing the raw material. Its acoustic and thermal performance were compared with the ones of six panels composed by other recycled materials (cork scraps, end-life tires, coffee chaff, waste paper, textile fiber mats, wool fiber scraps), assembled with similar techniques. Thermal resistance of RH is equal to 0.59 m2K/W, in the same order of magnitude of many traditional systems. Sound absorption coefficients were measured by means of the impedance tube. All the panels present acoustic absorption comparable with traditional ones (peak values 0.87–0.99). RH peak value is 0.87, while the maximum values are obtained for cork and wool fiber scraps (1 and 0.97 respectively). Life cycle analysis, performed in compliance with ISO 14040 showed the best environmental performance for the production of 1 m2 of RH and coffee chaff panels. Taking in account their acoustic and thermal behaviour, the wool fiber scraps presents a very good performance.

8th International Conference on Sustainability in Energy and Buildings, SEB 2016 The influence of granules size in silica aerogels is experimentally investigated in terms of thermal and acoustic performance characteristics. The transmission loss (TL) is measured at normal incidence in a traditional impedance tube, whereas the thermal conductivity (?) is evaluated using a Hot Plate apparatus, setting up an appropriate methodology, due to the nature of the sample. The results reveal that the small granules (granules size in the 0.01-1.2 mm range), which have the highest density, have the best performance both in terms of thermal and acoustic properties. Depending on the granules size, ? varies in 19-22 mW/mK range at 10°C, whereas a TL equal to 13 dB at about 6400 Hz for 20 mm thickness is obtained for small granules. © 2017 The Authors.

Glycerol is a co-product compound of biodiesel production with an interesting heating value. In this work pyrolysis kinetic parameters for a pellet made with a mass fraction of 90% sawdust and a mass fraction of 10% glycerol are derived through thermogravimetric analysis. A new parallel reaction scheme with four components (cellulose, hemicellulose, lignin and glycerol) is adopted and the kinetic triplet for each component is derived using a model fitting approach applied to this particular kind of pellet. The isoconversional method Kissinger-Akahira-Sunose is employed both to provide initial values for model fitting simulations and to check final results. Results show that activation energies and pre-exponential factors are respectively: 149.7 kJ mol−1 and 1.98*1011 s−1 for hemicellulose, 230.1 kJ mol−1 and 1.84*1017 s−1 for cellulose, 154.3 kJ mol−1 and 5.14*109 s−1 for lignin, 74.5 kJ mol−1 and 2.17*105 s−1 for glycerol with a first reaction order for all components, except for lignin (n = 2.6). Through evolved gas analysis it was demonstrated that the thermal degradation of glycerol contained in the pellet can increase hydrogen content in pyrolysis gases.

Beef cattle production is a widespread activity in Italy in the agricultural field and determines an important impact on environment and resources consumption. Carbon footprint evaluation is thus necessary to evaluate the contributions of the different stages and the possible improvements of the production chain. In this study, two typical Italian beef production systems, a conventional and an organic one are investigated in order to evaluate the greenhouse gas emissions from "cradle to gate farm" by a Life Cycle Assessment (LCA) approach; the carbon footprint (CF) per 1kg of live weight meat is calculated. The contributions from feed production, enteric fermentation, and manure management are taken into account, in order to compare the life cycle of the two productions; also the carbon balance in soil is evaluated, in order to verify the impact in a life cycle perspective. The results of CF calculation of the two farms show that organic system (24.62kgCO2eq/kg live weight) produce more GHG emissions than the conventional one (18.21kgCO2eq/kg live weight) and that the enteric fermentation is the more heavy contribution, with a range of 50-54% of the global CF value. Improvements of the production chain could be realized by accurate feeding strategies, in order to obtain reduction of methane emissions from enteric digestion of cattles.

Building retrofitting plays a key-role in energy saving and a growing interest is focused on insulating materials that allow a reduction in heat loss from envelopes with low thickness, by a process of reducing heating and cooling demand. In this context, a complete characterization of the physical properties of Moroccan natural gypsum materials was carried out. Basic information on the mineralogical, microstructure, thermal, mechanical, and acoustic characteristics of the rocks sampled from two Moroccan regions is provided. It was found that mineralogy, porosity, and water content are the main factors governing the development of the structure and the strength of the samples. The measured values of the porosity were 8.94%, the water content varied between 2.5&ndash, 3.0% for the two studied typologies, coming from Agadir and Safi, respectively. Gypsum powder was used for fabricating samples, which were investigated in terms of thermal and acoustic performance. Thermal properties were measured by means of a hot disk apparatus and values of conductivity of 0.18 W/mK and 0.13 W/mK were obtained for Agadir and Safi Gypsum, respectively. The acoustic performance was evaluated in terms of absorption coefficient and sound insulation, measured by means of a Kundt&rsquo, s Tube (ISO 10534-2). The absorption coefficients were slightly higher than the ones of conventional plasters with similar thickness. A good sound insulation performance was confirmed, especially for Safi Gypsum, with a transmission loss-value up to about 50 dB at high frequency.

The paper deals with the experimental characterization of double glazing units with granular aerogel in cavity at laboratory and pilot scale. In the laboratory investigation, three granule sizes and three aerogel layer thicknesses (10–35 mm) were considered. Light transmittance is in the 0.41–0.75 range (the highest values for the highest granule size and the minimum thickness). The U-value is 1.5 W/m2 K with 10 mm aerogel, whereas it decreases to 0.5 W/m2 K when considering 35 mm of aerogel, regardless of the granules size. After a systematic characterization, aerogel with large granules, the most common on the market, was chosen for an investigation at pilot scale. A window composed of two 6 mm clear float glasses and 15 mm aerogel in gap was tested in an experimental field with two boxes, in comparison with a conventional window. Aerogel sample allowed a reduction in the peak value of the indoor temperature of about 8–9 °C during sunny days, while similar values were achieved in the two test boxes during the night.

Sound absorption materials structure is generally based on porous synthetic media (rock wool, glass wool, polyurethane, polyester, ect.): they have expensive production processes, important energy consumptions, and high environmental impact. Recycled materials are becoming an interesting alternative, due to their good acoustic behavior, similar to traditional porous materials; they also allow low impact production costs, thanks to the use of wastes derived from other production cycles. This work focuses on the evaluation of the acoustic absorption properties of new panels made of recycled paper and other scrap materials, as wool and nonwoven polyester fabric: different samples were produced and tested by means of impedance tube, according to ISO 10534-2. In order to present the environmental benefits, Life Cycle Assessment was carried out in terms of primary embodied energy and greenhouse gas emissions, considering a “cradle-to-gate” approach. Furthermore, the behavior of innovative absorption materials was investigated in order to improve the acoustic performance of a lecture room, by means of an acoustic simulation software. A comparison with traditional materials was also carried out for both acoustic and environmental aspects. In the simulation model, calibrated by an in-situ experimental campaign of the main acoustic quality indexes (Reverberation Time, Clarity and Definition Indexes, Speech Transmission Index), different acoustic correction solutions were implemented: both the new recycled and traditional panels were applied as wall and ceiling absorbers. The analysis of the acoustic absorption trends, in 100 - 5000 Hz frequencies range, shows that the new materials are suitable as acoustic correction systems, especially the panel composed by waste paper and wool fibers. The LCA analysis results show that, considering the same acoustic performance, the recycled panels allow to reduce the environmental effects and the global production costs.

The energy efficiency of buildings can be evaluated by using the methodology provided by European regulations; however, this method required a lot of information which is generally not available for the existing buildings. In this paper an alternative method for the energy efficiency investigation of buildings is proposed and tested by means of Artificial Neural Networks (ANNs); an existing building built in 1990 and located in Perugia was chosen as case study and it was investigated by adopting both the mentioned approaches. An experimental campaign was also carried out in order to implement and validate the 3D model developed in TRNSYS. Results showed that the indoor air temperature trend simulated with ANN is closer to the measured data than the one simulated with TRNSYS, with lower mean error and MSE values. The energy consumption simulated with ANN is slightly higher than the one returned by using TRNSYS code of about 20 kWh/m 2 year (difference lower than 7%). In agreement with the results, the proposed method can be considered as an alternative tool that can be used for the thermal-energy investigation of existing buildings, with important money and time saving.