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The 1st International Conference on Buildings, Energy, Systems, and Technology (BEST 2016), was held in Belgrade, Serbia, on November 2-4,2016. This conference was an opportunity to bring together experts with different skills around the theme of building performance. It covered different aspects (technology, energy, environment, and economy), different scales (from the urban to the building level, including the built environment up to the single technical building systems), and different phases of the building process (from urban planning to building design, up to construction and management). This Special issue contains extended versions of some selected papers presented at BEST 2016, which went through a blind peer review of international experts. The present Editorial introduces the topics of the BEST 2016 and the contents of this Special issue. The focus of the Editorial is the theme of energy efficiency improvement in buildings; it provides an overview of state-of-the-art and of the legislation framework, and a discussion on research perspectives and trends. [ABSTRACT FROM AUTHOR]

The refurbishment of the existing building stocks represents a great potential for energy savings. To make the refurbishment effective, proper modeling of the current energy performance is needed. In most European countries, few and low quality data on the energy performance and on the refurbishment of building stocks are revealed, which increases the risk of not getting representative results. The article presents a new methodology for an effective bottom-up energy modeling, aimed at evaluating the current energy performance of housing stocks. The model is set up according to the IEE-EPISCOPE Project (Energy Performance Indicator Tracking Schemes for the Continuous Optimisation of Refurbishment Processes in European Housing Stocks, 2013-2016), which developed a framework of reliable data and clearly stated model assumptions, as to overcome the lack of data while guaranteeing transparency. The model, applied to an Italian region, is based on statistical data and uses the building typology approach. The energy performance is calculated by means of a quasi-steady state method. A correlation between the estimated and the real energy consumption is obtained. The model allows disaggregating the residential building stock in subsets to identify the main potential for energy savings in specific contexts. Improvements of the current data availability are strongly advisable to keep the model updated. [ABSTRACT FROM AUTHOR]

The article illustrates the Italian pilot action in the IEE-EPISCOPE project, focussing on the analysis of energy refurbishment trends of the Piedmont region residential building stock. The methodology follows three steps: (1) definition of a knowledge-base on the current state of the building stock, (2) investigation of refurbishment scenarios considering energy efficiency measures and retrofit rates, and (3) comparison of the achievable CO 2 reductions with the climate protection targets in short and middle term. The results are addressed to local authorities to enable them to set up corrective actions to achieve the targets. Three realistic scenarios are investigated. The first one considers the annual current refurbishment trend and the most common energy efficiency measures. The second scenario applies the measures resulting from a cost-optimal analysis. The third scenario considers the mean annual refurbished floor area necessary to meet the climate protection targets. The results of the scenario analyses emphasise the need of implementing major refurbishments, rather than fixing stricter requirements. The building stock energy performance is assessed through the building typology approach defined in the IEE-TABULA project. It allows the models of building stock energy refurbishment to be presented in an effective way, easily understandable and manageable by non-energy experts. [ABSTRACT FROM AUTHOR]

As reported in the scientific literature and mentioned in building energy performance legislation, the thermal inertia of the opaque building envelope can have a significant positive impact on the reduction of summer indoor overheating, of space cooling peak load and of electricity consumption. At the early stages of the envelope design, there is a need to use simplified as well as effective parameters to correctly characterize the thermal performance of the opaque envelope under dynamic conditions. In this work, a new methodology to describe the dynamic thermal behavior of opaque components is proposed. The approach is based on the harmonic parameters specified in ISO 13786 but it also takes into account realistic boundary conditions for different orientations and solar absorptance values. New equivalent thermal parameters are determined by means of dynamic simulations. The use of these parameters to assess the conduction heat flow rate by means of a simplified model is validated through a comparison with the results of a dynamic simulation. The method presented in the article represents an improvement with respect to the parameters usually applied at the early design stage to thermally characterize the opaque envelope of the building under dynamic conditions. In fact, it allows simplified but reliable performance parameters referring to actual boundary conditions to be obtained. The application potential of the proposed methodology lies in the drawing-up of catalogues and technical standards that supply the values of the new equivalent thermal parameters for different technical solutions. [ABSTRACT FROM AUTHOR]

Abstract: This article presents the results of a research aimed at obtaining detailed knowledge on the thermal characteristics of the building for the summer performance, particularly focusing on thermal insulation level. A new methodology for the analysis of the parameters having the most effect on space cooling energy performance of a building is presented. The proposed methodology involves analysing the different contributions to the internal air convective heat balance and their interrelations with different boundary conditions. It is applied, by means of a multi-step dynamic numerical simulation, to a parametric analysis of two case studies, a residential and an office building. The contribution of the energy transmission through the building envelope to the building energy performance for cooling is compared with the contribution of the energy not transmitted through the envelope. The influence of the single parameters related to the envelope, and in particular the effect of the thermal insulation level, are investigated through the application of a sensitivity analysis. The methodology could be used in different applications: in the energy design of new buildings or in an energy audit of existing buildings, because of its potentiality to identify critical situations and to quantify the effects of improving solutions. [Copyright &y& Elsevier]

Abstract: Together with the evolution of buildings and systems, energy assessment models have become more and more detailed, requiring a precise evaluation of the building loads and gains. For an accurate analysis of solar heat gains, technical standards introduce an external shading reduction coefficient of the incident solar radiation, called shading factor. Its value is provided for simple geometries, which are usually not suitable to properly describe a real environment. In addition, the relations adopted to evaluate the shading factor are based on simplified hypotheses, which cause non-negligible errors when compared to more complex algorithms. The objective of this study is the development of a calculation procedure of the shading factor under complex boundary conditions. The algorithms have been implemented in a software tool written in Matlab language. It can provide for the value of the shading factor on a generically oriented and tilted surface. After setting the site and the time for the simulation, generic-shaped windows can be modelled. The external environment, which can be imported from DXF files, can include a horizon profile, generic-shaped obstructions and vegetation. The calculation can be performed for every sky condition: clear, average or generic. In addition, the simulation can be run to obtain instantaneous, daily average or monthly average shading factor values. [Copyright &y& Elsevier]

Abstract: Increasing interest is currently being addressed to multi-energy systems in buildings. These systems integrate different energy sources, at least one of which is renewable, in order to cover the thermal and electrical loads of a building. Since the design and operation of such systems are very complicated for many reasons (e.g. the intermittent nature of the renewable sources, the highly interlinked system layouts), it is of the foremost importance to provide tools to help select the best system configuration and energy sources mix. A modelling approach to multi-energy systems in buildings, based on the energy hub concept is presented in this work. This approach allows the coupling between the energy demand and the energy supply in a building to be modelled in a synthetic way. The model was customised to be used at the concept stage of the building design, either as a system simulation tool or as a system selection tool. If the prices and the characteristics of the energy converters and of the energy-wares are known, it is possible, with a certain set of constraints, to determine the configuration that minimises the initial investment costs, the use of non-renewable sources or the life-cycle costs. This approach makes it possible to avoid the simulation and ranking of a set of different system configurations, and also permits the study of the behaviour of such systems in an open configuration and not as individual systems. An application of the methodology to a case study is provided. [Copyright &y& Elsevier]

One of the main tasks of the European Energy Performance of Buildings Directive 2002/91/EC (EPBD) pertains to energy building certification. For this purpose, recent European standards have defined a methodology for the assessment of the energy use of buildings through the calculation of energy ratings. The accuracy of the energy rating depends both on the detail level of the model and on the confidence of the input data. In this work, the quasi-steady simplified monthly method, presented in the ISO 13790 : 2008 standard, has been applied to a dwelling in Turin, Italy, in order to calculate its energy rating. A widespread list of 129 input data was identified and grouped into three sets: climatic data, envelope data, and building use data. Probability density functions were assigned after a detailed bibliographic research. The Monte Carlo Latin hypercube sampling technique has been used to assess the building energy needs confidence interval and the energy performance class uncertainty. A sensitivity analysis based on the Morris method, has also been performed for the different building heat balance terms, in order to identify the most important parameter set that takes into account for the uncertainty in the model output. The main results demonstrate that the asset energy rating is only slightly affected by data uncertainties; moreover, the analysis highlights the importance of associating an operational energy rating to the asset rating in order to show the influence of user behavior on building energy performance. On the other hand, the results show that less than 10 input data, among the considered 129 ones, have a significant influence on the energy rating uncertainties. [ABSTRACT FROM AUTHOR]

Abstract: The objective of this work is to contribute to the recent standardisation activity, finalized to apply the Energy Performance of Buildings Directive (EPBD). Through the energy assessment of some residential buildings in Turin (Italy), the work investigates the application of the calculation methods that have been specified in the recent European standard for the so-called “standard energy rating”. A comparison of the “calculated energy rating” with the “measured energy rating” is used to investigate the effect of user behaviour and weather conditions. Moreover, in order to draft the energy certificate and make an appropriate classification, the last part of the work investigates the way to find energy reference values of the building stock, through the study of the correlation between the input and the output data of an energy rating and the comparison of the analysed buildings. [Copyright &y& Elsevier]

Abstract: This paper presents a comparison between measured and calculated acoustical parameters in eight high school classrooms. The mid frequency unoccupied and occupied reverberation times and the 1kHz sound propagation (SP) of the reverberant and total speech levels in occupied classrooms were compared with analytical and numerical predictions. The ODEON 6.5 code and the Sabine formula gave the most accurate results for reverberation time in the empty classrooms with overall relative differences of 8.1% and 9.7%, respectively. With students present, the Eyring and Sabine formulas and Hodgson’s empirical model resulted to be the most accurate with relative differences of 11.1%, 13.2% and 13.6%, respectively. The reverberant speech levels decrease with increasing distance from the source at rates varying from −1.21 to −2.62dB/distance doubling, and the Hodgson model fits the slope values quite well. The best predictions of the SP of the reverberant and total speech levels are shown, in order of accuracy, for the ODEON code, the Barron and Lee theory and the classical diffuse field theory. Lower rms errors were found when the measured total acoustic absorptions were used. The lowest rms error of 1.4dB for the SP of the total speech level were found for both the ODEON code and the Barron and Lee theory. [Copyright &y& Elsevier]

Abstract: A field survey was carried out in order to collect, elaborate and analyse data concerning the actual energy consumption for space heating of a sample of about 140 buildings (120 high schools) in the Province of Torino (Italy). The buildings were equipped with heat meters. For each building the primary energy consumption (i.e. the fuel consumption multiplied by its net heat value), the metered supplied thermal energy, the daily and seasonal operating periods and the climatic data of the site were monitored. The energy consumption data, both annual and monthly, were normalised and statistically analysed in order to compare different buildings and different heating seasons. The study aimed at evaluating a “specific energy performance indicator related to space heating” for each building. This indicator may be used to establish benchmark values in heat energy service contracts, to predict heat energy consumption or to verify the increasing/decreasing of the actual consumptions in future heating seasons with respect to the benchmark value. Moreover, this is very useful to find out those buildings not complying energy requirements and, as a consequence, requiring a deeper energy diagnosis. The study is part of a research project between Politecnico di Torino and Provincia di Torino, stimulated by the Directive 2002/91/EC on building energy performance, focused on evaluating the energy performance of existing buildings. [Copyright &y& Elsevier]

Abstract: The objective of this work is to implement a simplified calculation procedure for building net energy need, based on a quasi-steady state model and on a monthly data set. In particular, it is intended to supply a formulation of the dynamic parameters and to adapt them to Italian climatic, typological, constructive and user data. The method was validated by determining the numerical correlations of the gain/loss utilization factor, through a comparison with a detailed building energy simulation software (EnergyPlus). The simulation was run on some test rooms defined by CEN (European Committee for Standardization) and on some real buildings that are representative of the Italian building stock, assuming weather data from different Italian locations (Torino, Roma, Palermo). The work shows that the accuracy of results is greatly affected by nonlinearities in the determination of the heat transfer and that the dynamic parameters are sensitive to some building features which are not taken into account in the CEN correlations. [Copyright &y& Elsevier]

An introduction is presented in which the editor discusses various reports published within the issue which include the integrated performance of different glazing systems, the performance of sustainable materials, and the effect of grout thermal conductivity.

Calibration of the existing building simulation model is key to correctly evaluating the energy savings that are achievable through retrofit. However, calibration is a non-standard phase where different approaches can possibly lead to different models. In this study, an existing residential building is simulated in parallel by four research groups with different dynamic simulation tools. Manual/automatic methodologies and basic/detailed measurement data sets are used. The calibration is followed by a validation on two evaluation periods. Monitoring data concerning the windows opening by the occupants are used to analyze the calibration outcomes. It is found that for a good calibration of a model of a well-insulated building, the absence of data regarding the users' behavior is more critical than uncertainty on the envelope properties. The automatic approach is more effective in managing the model complexity and reaching a better performing calibration, as the RMSE relative to indoor temperature reaches 0.3 °C compared to 0.4–0.5 °C. Yet, a calibrated model's performance is often poor outside the calibration period (RMSE increases up to 10.8 times), and thus, the validation is crucial to discriminate among multiple solutions and to refine them, by improving the users' behavior modeling. [ABSTRACT FROM AUTHOR]

Abstract: Along with the entry into force of the new European Directive 2010/31/EU on the Energy Performance of Buildings (EPBD recast), each Member State has the responsibility of supporting activities for the construction of nearly zero energy buildings with a very high energy performance. In order to achieve the new EU directive targets, designers, in addition to having to use innovative building components, also have to pay more attention to the construction details which mostly affect building envelope heat losses. It is therefore necessary not only to properly design structural nodes, in order to minimize such energy losses, but also to identify accurate numerical methods in order to appreciate the benefits of a proper design. A sensitivity analysis based on an extensive study of the linear thermal transmittance value of many types of thermal bridge, based on the methodology specified in EN ISO 10211, has been carried out in the presented work. After having defined the input design variables and considering a range of variation for each of them for the linear thermal transmittance evaluation, a non-linear regression model has been specifically developed for each analyzed thermal bridge, considering the output values of a numerical code as data set. In order to perform the sensitivity analysis a significant and representative number of cases have been generated, using a sampling technique. The ANOVA–FAST method has been performed, on the basis of the obtained results, in order to assess the contribution of each input design variable to the deviation of the linear thermal transmittance for each kind of thermal bridge. [Copyright &y& Elsevier]

Abstract: The article presents a new approach in which the Analysis Of Variance (ANOVA) is used to identify the design variables that have the most impact on the variation of the building energy performance for a typical office building and to allocate the contribution of each variable to this variation. Moreover, the study addresses an important issue concerning the identification and the setting of a set of simple and concise variables that can be used during the conceptual design stage of office buildings. The analysis shows that the suggested approach could be useful for architects to evaluate the degree to which each design variable contributes to the variability of the building energy performance. Besides, the results may be helpful to support policymakers during the elaboration of energy codes by providing adequate information for the selection and handling of the parameters that control the variability of the energy needs. [Copyright &y& Elsevier]

The compliance with the indoor environmental quality (IEQ) requirements should be considered when designing retrofit actions for the refurbishment of existing buildings. The research is aimed to reduce the imbalance between the visual and thermal domains through the improvement of different design parameters in compliance with the nearly zero-energy building (nZEB) requirements. The article proposes a novel approach based on the integrated lighting, thermal, and energy dynamic simulation, to evaluate the overall building performance according to energy saving, cost effectiveness, and IEQ multi-criteria. Different energy efficiency actions, in terms of insulation materials, glazing solutions, and control strategies of the solar shading devices, have been applied to an existing office building-type. The analysis shows the possibility to design the refurbishment of an existing building into a nZEB while ensuring visual and thermal comfort. However, the not negligible costs lead to an incompliance with the cost-effectiveness requirements. [ABSTRACT FROM AUTHOR]

The EU Member States are being involved to develop long-term strategies and to promote investments aimed at improving the energy efficiency of the building stock, at increasing the use of Renewable Energy Sources (RES) and at growing the number of Nearly Zero-Energy Buildings (NZEBs). The aim of this article is to investigate energy and economic implications related to the exploitation of RES in the transformation of an Italian social housing building-type into a NZEB. The research is based on a detailed energy audit procedure that includes cost-optimal assessment and compliance check with the legal requirements. A parametric analysis was performed to find out the technical building system configurations that verify the minimum share of RES established by the Italian regulations, and at the same time to assess global cost and payback period. The intersection between legal compliancy and cost-effectiveness narrows the field of applicable RES technologies that are limited to electric heat pump for heating and cooling coupled with PV system, and low size solar collectors coupled with low temperature generator for domestic hot water. Improvements in the energy policy are necessary to guarantee the best trade-off between RES exploitation, energy efficiency and costs, as to preserve market equilibrium. • The economic implications of the minimum RES share set by regulations are assessed. • The analysis is performed on a social housing building transformed into NZEB. • Cost-optimal technical building systems using RES are identified. • Cost-optimal energy efficiency measures do not comply with legal EP requirements. • The heat pump coupled with the photovoltaic system is a cost-effective solution. [ABSTRACT FROM AUTHOR]

Purpose: The evaluation of the association between different exposure to pesticides and different types of comet images among a group of 26 recruited subject. Material and methods: We have recruited 26 subjects (farmers and not farmers). They were submitted to a blood drawing of 10 mL and a questionnaire was administered to investigate personal habits and work history. By means of the comet assay it was assessed the oxidative DNA damage of peripheral lymphocytes by pesticides in the exposed and non-exposed workers. Result: The data measured by means of the comet were log transformed and the associations (odds ratios – ORs) with the single pesticides were calculated. The regression analysis shows a significant dose effects relationships between the Intensity Score of pesticides exposures tail moment (TM) and other measured parameters. Insecticides TM OR = 17.00 [1.47 – 196.41]. This relationship is independent from the smoking habits. Conclusions: TM values higher than the 75° percentile were significantly associated with the exposure to particular insecticides such as chlorpyriphos, deltamethrin and with other pesticides (near the statistical significance). [ABSTRACT FROM AUTHOR]

Background: Occupational exposure is known to play a role in the aetiology of lymphomas. The aim of the present work was to explore the occupational risk of the major B-cell lymphoma subtypes using a case-control study design. Methods: From 2009 to 2014, we recruited 158 lymphoma cases and 76 controls in the provinces of Bari and Taranto (Apulia, Southern Italy). A retrospective assessment of occupational exposure based on complete work histories and the Carcinogen Exposure (CAREX) job-exposure matrix was performed. Results: After adjusting for major confounding factors, farmers showed an increased risk of diffuse large B-cell lymphoma (DLBCL) [odds ratio (OR) =10.9 (2.3-51.6)] and multiple myeloma (MM) [OR = 16.5 (1.4-195.7)]; exposure to the fungicide Captafol was significantly associated with risk of non-Hodgkin lymphoma (NHL) [OR = 2.6 (1.1-8.2)], particularly with the risk of DLBCL [OR = 5.3 (1.6-17.3)]. Conclusions: Agricultural activity seems to be a risk factor for developing lymphoma subtypes, particularly DLBCL, in the provinces of Bari and Taranto (Apulia Region, Southern Italy). Exposure to the pesticides Captafol, Paraquat and Radon might be implicated. [ABSTRACT FROM AUTHOR]

The recently issued EN ISO 52016-1 technical standard provides a new simplified dynamic method for the building energy performance assessment. Since an extensive validation of the EN ISO 52016-1 hourly method is still missing, the present work investigates the effect of the main modelling assumptions—related to the heat balance on the outdoor and the indoor envelope surfaces—on the building thermal behaviour. The model validation was carried out by assessing the accuracy variation consequent to the application of the EN ISO 52016-1 modelling assumptions to a detailed dynamic calculation tool (EnergyPlus). To guarantee a general validity of the outcomes, two buildings, two levels of thermal insulation, and two Italian climatic zones were considered, for a total of eight case studies. To explore different applications of the standard method, the analysis was performed both under a free-floating condition—to evaluate the accuracy of the model in predicting the indoor operative temperatures—and to assess the annual energy needs for space heating and cooling. Results show that the assumptions related to the definition of the external convective and the shortwave (solar) radiation heat transfer lead to non-negligible inaccuracies in the EN ISO 52016-1 hourly model. [ABSTRACT FROM AUTHOR]

(1) Background: The association of radon-222 with lung cancer is well studied. The aim of the study was to validate a model of indoor radon measurements, to apply radon software to estimate lung cancer cases that are attributable to radon and to study the relationship between radon and earthquakes. (2) Methods: Different data detectors were used to obtain radon measurements in different places. Continuous data collection and predictions of indoor radon concentrations were carried out. Software was used to assess radon-attributable lung cancer cases, and data related to earthquake magnitudes were downloaded from Italian Vulcanology Institute. (3) Results: As expected, the highest radon concentrations were observed on the ground floor (232 ± 232 Bq/m3), with higher values measured during winter than in other seasons. The comparison of the detectors showed the overlapping of the two detectors-measured data sets. The cases of lung cancer that were attributable to radon in Locorotondo were studied (3.66/10,000). From the multivariate analysis of the relationship between high radon concentrations and high earthquake magnitude values, they show statistically significant ORs of just over 1. (4) Conclusions: Although the measured values are, on average, within the reference level, prevention measures must be implemented, as the measured radon values allow us to estimate an expected value of 3.66 cases of lung cancer per 10,000 people in the resident population. [ABSTRACT FROM AUTHOR]

The research investigates the validity of the simple hourly method, as introduced by the EN ISO 52016-1 standard, for the assessment of the building energy demand for heating and cooling, by comparing it with a detailed dynamic model (EnergyPlus). A new methodology is provided to identify and quantify the causes of deviations between the models. It consists in the split of the contributions of the air heat balance (AHB) equation by dynamic driving force, and in the adoption of consistency options of the modeling parameters related to specific physical phenomena. A case study approach is adopted in the article to achieve the research objective. The results show that the deviations in the heating and cooling loads between the two calculation methods can be mainly ascribed to the use of different surface heat transfer coefficients, and to a different modeling of the extra thermal radiation to the sky. Providing a methodology to validate the calculation method, this work is intended to contribute to the enhancement of the use of simple dynamic models and to the improvement of the standardization activity. [ABSTRACT FROM AUTHOR]

Heat and moisture (HM) transfer simulations of building envelopes and whole building energy simulations require adequate weather files. The common approach is to use weather data of reference years constructed from meteorological records. The weather record affects the capability of representing the real weather of the resulting reference years. In this paper the problem of the influence of the length of the records on the representativeness of the reference years is addressed and its effects are evaluated also for the applicative case of the moisture accumulation risk analysis with the Glaser Method and with DELPHIN 6, confirming that records shorter than 10 years could lead to less representative reference years. On the other hand, it is shown that reference years obtained from longer periods are not representative of the most recent years, which present higher dry-bulb air temperatures due to a short-term climate change effect observed in all the considered weather records. An alternative representative year (Moisture Representative Year) to be used in building energy simulations with a strong dependence on moisture is presented. [ABSTRACT FROM AUTHOR]

After publication of our article [1] we have been notified us that one of the author names have been incorrectly spelled. [ABSTRACT FROM AUTHOR]

Directive 2010/31/EU promotes the refurbishment of existing buildings to change them into nearly zero-energy buildings (nZEBs). Within this framework, it is of crucial importance to guarantee the best trade-off between energy performance and indoor environmental quality (IEQ). The implications of a global refurbishment scenario on thermal and visual comfort are assessed in this paper pertaining to an existing office building. The retrofit actions applied to achieve the nZEB target consist of a combination of envelope and technical building systems refurbishment measures, involving both HVAC and lighting. Energy and comfort calculations were carried out through dynamic simulation using Energy Plus and DIVA, for the thermal and visual performance assessments, respectively. The results point out that energy retrofit actions on the building envelope would lead to significant improvements in the thermal performance, regarding both energy savings (−37% of the annual primary energy for heating) and thermal comfort. However, a daylighting reduction would occur with a consequent higher electricity demand for lighting (36%). The research presents a detailed approach applicable to further analyses aimed at optimizing the energy efficiency measures in order to reduce the imbalance between visual and thermal comfort and to ensure the best performance in both domains. [ABSTRACT FROM AUTHOR]