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Ecuador is a country with several climate zones. However, their behaviour is similar throughout the year, with no peaks of extreme temperatures in the various seasons. This paper is a first approach to study the adaptive comfort behaviour in several areas and populations of the country. Considering the ASHRAE 55-2020 model, energy simulation programmes are applied not just to the current climate scenario but also to the climate change scenarios of 2050 and 2100. The results of locations are analysed and compared to determine their performance. Thanks to their climate characteristics, adaptive comfort models could be applied as a passive strategy, using natural ventilation for building indoor comfort improvement, particularly social dwellings. According to previous studies, some prototypes have not considered the climate determinants in each region. Given the geographic situation of the study areas, the adaptive comfort model could be applied in all cases. Percentages of application of natural ventilation and heating and cooling degree hours have similar behaviours according to the climatic region, with a variation greater than 30% among them. [ABSTRACT FROM AUTHOR]

In this paper, the authors first clarify the definition of building microclimate in free-running buildings and the relationship with summer thermal comfort. Next, field measurements were conducted to investigate the microclimate in a Chinese traditional vernacular house. Subsequently, the results of measurements were compared with a dynamic thermal and a CFD simulation in order to determine the building microclimate and thermal comfort of the present vernacular house over the period of an entire summer. The field measurements show the present Chinese vernacular house has its own independent building microclimate in summer, which is in accordance with the main character of microclimate in terms of different distributions of solar gain, air temperature and wind velocity in different spaces. The simulation results of the vernacular house could be matched well with the field measurements. According to the simulations, at night, a comfortable temperature could be obtained throughout most of the summer period whereas in the daytime the operative temperature was higher than the comfortable temperature for one-third of the summer period. Wind velocity in the semi-outdoor and outdoor spaces however, improves the thermal comfort significantly. The thermal comfort environment can thus not only change in time but also in space. This example of the vernacular building shows that it is possible to create comfortable conditions for the inhabitants when not only the indoor climate is taken into account but the whole building microclimate as defined in this paper. This paper also shows that the simulations can predict the building microclimate. [ABSTRACT FROM AUTHOR]

Ecuador is a country with several climate zones. However, their behaviour is similar throughout the year, with no peaks of extreme temperatures in the various seasons. This paper is a first approach to study the adaptive comfort behaviour in several areas and populations of the country. Considering the ASHRAE 55-2020 model, energy simulation programmes are applied not just to the current climate scenario but also to the climate change scenarios of 2050 and 2100. The results of locations are analysed and compared to determine their performance. Thanks to their climate characteristics, adaptive comfort models could be applied as a passive strategy, using natural ventilation for building indoor comfort improvement, particularly social dwellings. According to previous studies, some prototypes have not considered the climate determinants in each region. Given the geographic situation of the study areas, the adaptive comfort model could be applied in all cases. Percentages of application of natural ventilation and heating and cooling degree hours have similar behaviours according to the climatic region, with a variation greater than 30% among them.

Recent climate change projections estimate that the average summertime temperature in the southern part of Great Britain may increase by up to 5.4°C by the end of the century. The general consensus is that projected increases in tem-perature will render British dwellings vulnerable to summer overheating and by the middle of this century it may become difficult to maintain a comfortable indoor environment, if adaptation measures are not well integrated in the design and operation of new dwellings, which are likely to remain in use beyond the 2050s. The challenge is to reduce overheat-ing risks by integrating building and user adaptation measures, to avoid energy intensive mechanical cooling. Developing guidelines and updating building regulations for adaptation, therefore, requires an understanding of the baseline scenario; i.e. the performance of existing buildings in future climates. This paper aims to investigate the performance of new-build multi-occupancy British dwellings for human thermal com-fort in the present-day and projected future climates in four regional cities: Birmingham, Edinburgh, London and Manchester. Evaluations are carried out by a series of dynamic thermal simulations using widely adopted threshold tem-perature for overheating, as well as adaptive thermal comfort standards. This study thus offers a unique perspective on regional variations of performance and provides a clearer snapshot because of the use of more appropriate adaptive comfort standards in the evaluations. Finally, the paper sheds light on possible personal and building adaptation mea-sures to alleviate overheating risks. [ABSTRACT FROM AUTHOR]

In a changing climate there is increasing concern about the risk of overheating in UK buildings, particularly those with a low-carbon footprint which cannot rely on mechanical cooling. This gives rise to concern among building professionals about how overheating risk can best be assessed. Current Chartered Institution of Building Services Engineers (CIBSE) guidance uses a simple definition of overheating as the exceedance of 28°C for more than 1% of occupied hours, based on simulations using weather files from a 'design summer year' (DSY). There is increasing evidence that this criterion is both insensitive and open to abuse. This paper uses field surveys of thermal (dis)comfort and the adaptive thinking behind the British and European Standard BS EN15251 to propose a new approach. It takes account of the effect of indoor and outdoor climate on the dissatisfaction of building occupants. An alternative definition of overheating in buildings is proposed, along with an approach to predicting the magnitude and/or frequency of occurrence of overheating in buildings. Dans un climat en evolution, il existe une preoccupation croissante a l'egard du risque de surchauffe dans les immeubles du Royaume-Uni, en particulier ceux qui ont une empreinte carbone faible et ne peuvent pas compter sur un refroidissement mecanique. Cela amene les professionnels du batiment a se preoccuper de la maniere dont le risque de surchauffe peut etre le mieux evalue. Les informations actuellement fournies a titre indicatif par le CIBSE (Chartered Institution of Building Services Engineers) utilisent une definition simple de la surchauffe comme etant des temperatures depassant 28°C pendant plus de 1% des heures d'occupation, sur la base de simulations utilisant les fichiers meteorologiques de l'indice DSY (« Design Summer Year ») correspondant a une annee a ete chaud moyenne. Il est de plus en plus manifeste que ce critere n'a pas la sensibilite necessaire et incite aux abus. Cet article utilise des enquetes de terrain portant sur le confort ou l'inconfort thermique et les idees d'adaptation qui sous-tendent la norme britannique et europeenne BS EN15251 afin de proposer une approche nouvelle. Il prend en compte l'effet du climat interieur et exterieur sur l'inconfort des occupants de l'immeuble. Une autre definition de la surchauffe dans les immeubles est proposee, ainsi qu'une approche permettant de prevoir l'ampleur et/ou la frequence de l'apparition de cette surchauffe dans les immeubles. Mots cles: confort thermique adaptatif, confort, annee a ete chaud (DSY), inconfort, surchauffe, normes [ABSTRACT FROM AUTHOR]

Seasonal variation of thermal comfort demands directly affects the energy needs for heating or cooling purpose. In previous studies, the differences of neutral temperatures between summer and winter were revealed, but the studies on the difference of human thermal adaption in transitional seasons are insufficient. To clarify this, this paper presents a year-long survey which was carried out in 505 residential buildings in six cities located in the Hot Summer and Cold Winter (HSCW) zone of China involving 11,524 subjects. Results show a significant difference of adaptive responses in different seasons, and a lag of behavioral responses behind climate change in transitional seasons is observed. Occupants not only adjust clothing insulation according to air temperature in different seasons, but also actively control indoor air movement, including closing/opening windows and using fans. The seasonal, monthly and daily neutral temperatures are studied, implying that occupants’ thermal experience has significant effect on their thermal comfort by behavioral, physiological and psychological paths. According to the comparative study, the running mean air temperature method and aPMV model are recommended in free-running space. The findings provide scientific evidence to the concept that dynamic thermal comfort temperature range should be considered in evaluation of indoor thermal environment. [ABSTRACT FROM AUTHOR]

Previous adaptive thermal comfort research mainly emphasized the correlations between outdoor climate and thermal adaptation. In this paper, we explore the influence of indoor thermal experience on occupants' thermal adaptation, especially with regard to physiological adaptation. We also investigate whether people with distinct cold indoor exposures have different levels of physiological adaptation to cold environment. A comparative experiment, including both physiological measurements and subjective questionnaires, was conducted in China where winter indoor climates in the northern region (with pervasive district heating) are much warmer than the southern region (without district heating). Two subject groups were recruited, namely: (a) N–N group - subjects who had lived in the northern China with district heating all their life, and (b) S–N group - subjects who grew up in the southern region without district heating but recently moved to the north. The results indicate that S–N subjects who had lived their entire lives in cold wintertime indoor climates had slither physiological response and felt less uncomfortable in mild cold exposures than N–N subjects who lived in neutral-to-warm wintertime indoor climates. The findings suggest that indoor thermal exposures can also influence occupants' thermal adaptation, which can reserve as a reference to the future adaptive thermal comfort model. [ABSTRACT FROM AUTHOR]

India is witnessing unprecedented growth trends in building construction, particularly office spaces. Indian offices are designed to operate at 22.5 ± 1 °C all year round to meet the stringent “Class A” specifications outlined by international standards in the absence of an India-specific comfort standard. This paper proposes an India Model for Adaptive Comfort – IMAC – based on the field surveys administered in 16 buildings in three seasons and five cities, representative of five Indian climate zones. A total of 6330 responses were gathered from naturally ventilated, mixed mode and air-conditioned office buildings using instantaneous thermal comfort surveys. Occupants in naturally ventilated Indian offices were found to be more adaptive than the prevailing ASHRAE and EN models would suggest. According to the IMAC model, neutral temperature in naturally ventilated buildings varies from 19.6 to 28.5 °C for 30-day outdoor running mean air temperatures ranging from 12.5 to 31 °C. This is the first instance where a study proposes a single adaptive model for mixed mode buildings asserting its validity for both naturally ventilated and air-conditioned modes of operation in the building, with neutral temperature varying from 21.5 to 28.7 °C for 13–38.5 °C range of outdoor temperatures. For air-conditioned buildings, Fanger's static PMV model was found to consistently over-predict the sensation on the warmer side of the 7-point sensation scale. [ABSTRACT FROM AUTHOR]

Abstract: The building sector has a significant share in a county's total greenhouse gas emissions, and as a reaction to the Kyoto commitment most countries are constantly adjusting building energy requirements in order to reduce greenhouse gas emissions and mitigate the climate change. While it is easier to set standards for the building fabric and for technical systems, the impact of occupants on comfort and energy performance in buildings has proven to be important, but is a lot harder to account for. This paper therefore aims to investigate the magnitude of influence of occupants in relation to climate and architectural design on thermal comfort and CO2 emissions in offices in different climate zones of the world. The aim is to identify typical patterns and key parameters for optimisation. For this purpose, a parametric study for a typical cellular office room has been conducted using the simulation software EnergyPlus. Two different occupant scenarios are each compared with three different architectural design variations and modelled in the context of three different locations for the IPCC climate change scenario A2 for 2030. The evaluation of the results is focused on two different modes of operation. For natural ventilation adaptive thermal comfort according to ASHRAE Standard 55 has been evaluated, and for mixed mode operation final energy consumption and resulting CO2 emissions. The results indicate a first approach to estimate comfort levels based on climatic data, architectural design priorities and occupancy. Additionally, warmer climates seem to have larger optimisation potential for comfort and energy performance in offices compared to colder climates. [Copyright &y& Elsevier]

Abstract: This paper investigates the impact of a climate change scenario on comfort and energy performance in offices, in relation to the influence of building design and occupants. It focuses on a typical cellular office room in the context of Athens, Greece, as input for a parametric study using the building simulation software EnergyPlus. Three different building design variations are combined with two different occupant scenarios and a standard weather data set as well as the IPCC climate change scenario A2 for 2020, 2050 and 2080. Results are investigated from two different perspectives: For naturally ventilated buildings the evaluation is related to adaptive thermal comfort according to ASHRAE Standard 55 and EN 15251. And for mixed mode context the evaluation is focused on the resulting impact on final energy consumption, greenhouse gas emissions, peak heating and cooling loads and the percentage of working time when the building is free-running. The results indicate a significant impact of the climate change scenarios on adaptive thermal comfort, and they indicate differences in evaluation between ASHRAE Standard 55 and EN 15251. The comparison of climate change, building design and occupant scenarios indicates that building design is the key to thermal comfort optimisation, whereas the major mitigation potential regarding energy consumption and greenhouse gas emissions is related to occupant behaviour. [Copyright &y& Elsevier]

Abstract: The application of Trombe walls in temperate climates is problematic due to undesired heat gains and overheating phenomena in summer. A proper shading and ventilation of this system can reduce such drawbacks, but the impact of these strategies on the wall’s thermal parameters is yet not widely investigated in quantitative terms. This paper presents an experimental study on the thermal behavior of Trombe walls in summer under Mediterranean climate conditions. The aim of the study is to determine experimentally the thermal parameters of a Trombe wall in summer conditions through the changing of shading, ventilation and operational conditions. In order to do that a series of experimental campaigns were carried out on a case study. A detailed simultaneous monitoring of two Trombe walls made it possible to compare the thermal behavior by varying the screening, ventilation and internal gains conditions. Furthermore, monitoring of indoor thermal comfort conditions and energy simulation using a model in dynamic state were carried out. The results showed that shading, ventilation and occupancy conditions affect significantly the thermal parameters of Trombe wall in summer: screening with roller shutters determines a decrease in internal surface temperature of the wall of 1.4°C and a decrease in daily heat gains of about 0.5MJ/m2; the combined use of overhangs, roller shutters and cross ventilation for the Trombe wall can assure a satisfactory thermal comfort level in summer and a reduction of the cooling energy needs respectively of −72.9% and −63.0% for a dwelling with low or highly insulated building envelope in comparison with the case of an unvented Trombe wall without solar protections. [Copyright &y& Elsevier]

Temperatures in Mediterranean cities are rising due to the effects of climate change, with a consequent increase in the heat waves frequency. Recent research has shown the tempering potential of semi-outdoor spaces such as courtyards, which are semi-enclosed spaces that are widely used by the users of buildings in Mediterranean cities. International standards addressing thermal comfort parameters provide technical guidelines for indoor spaces only. Expanding this concept, this paper focuses on the potential to extend and interpret the existing calculation models for indoor thermal comfort, EN 16798 and ASHRAE 55, to determine thermal comfort, monitoring two different courtyards in Cordoba, Spain, during both typical summer and heat wave periods. The results show that during the typical summer, the monitored courtyards can reach temperatures up to 8.4 °C cooler than outside. Subsequently can be considered to be in thermal comfort on average for 88% of the time according to EN 16798, and 75% according to ASHRAE 55, which drop to 71% and 52% respectively during heat wave (HW) periods, in spite of increasing thermal gap (TG) up to 13.9 °C. The results are also compared with the PET indicator used for evaluation of outdoor thermal comfort, which provides comparable figures: 81% summer and 73% HW. Implications of implementing passive shading strategies to increase comfort in these transition spaces are also evaluated. The research highlights the thermal potential and usefulness of courtyards in warm climates, so they can ultimately be included in the building analysis as a potentially comfortable and habitable space. • Courtyard was included in the building analysis as a comfortable and habitable space. • Comfort adaptive assessment according to EN 16798, ASHRAE 55 and PET were confronted. • Courtyard tempering achieves a TG up to 8.4 °C in summer and 13.9 °C in a heatwave. • In warm locations, courtyards can be under comfort more than 75% of the day. • Shadow quantification proves to be a major strategy regarding extreme temperatures. [ABSTRACT FROM AUTHOR]

Abstract: Standards governing thermal comfort evaluation are on a constant cycle of revision and public review. One of the main topics being discussed in the latest round was the introduction of an adaptive thermal comfort model, which now forms an optional part of ASHRAE Standard 55. Also on a national level, adaptive thermal comfort guidelines come into being, such as in the Netherlands. This paper discusses two implementations of the adaptive comfort model in terms of usability and energy use for moderate maritime climate zones by means of literature study, a case study comprising temperature measurements, and building performance simulation. It is concluded that for moderate climate zones the adaptive model is only applicable during summer months, and can reduce energy for naturally conditioned buildings. However, the adaptive thermal comfort model has very limited application potential for such climates. Additionally we suggest a temperature parameter with a gradual course to replace the mean monthly outdoor air temperature to avoid step changes in optimum comfort temperatures. [Copyright &y& Elsevier]

• Building Bio-Climatic Charts are proposed for different climate change scenarios. • Time-varying significance of nine design parameters in this century are provided. • Effectiveness of airtightness will increase up to 329% by the end of this century. • Cooling potentials of natural ventilation will significantly decrease up to 69%. • A holistic passive design can reduce the building annual cooling load by 56.7%. The application of passive design strategies is crucial at the early architectural design stage for building energy use minimization. However, the time-varying effectiveness of passive design strategies in responding to future climate change in hot and humid climates are rather limited in the literature. This paper aims to examine the dynamic effectiveness of passive design strategies for residential buildings in Hong Kong under the context of future climate change. Using the newly developed hourly weather data and adaptive comfort standard model, the dynamic effectiveness of viable passive design strategies for residential buildings are evaluated over time in the 21st century by plotting Givoni building bio-climatic charts (BBCC) and simulation-based sensitivity analyses in a validated EnergyPlus model. Results show that solar protection strategies are still the highly sensitive strategies for building energy performance and the effectiveness of external windows' airtightness is expected to increase up to 329% by the end of this century, whereas the cooling potential of ventilation utilization will significantly decrease over time. When the different combination of sensitive passive design parameters is implemented onto the baseline residential building model for different climate scenarios, the annual and peak cooling load can be reduced up to 56.7% and 64.5%, respectively. [ABSTRACT FROM AUTHOR]

Providing thermal comfort in schools has a significant impact on students' performance and health. Climate change may result in an increased risk of overheating. A clear understanding and definition of overheating in schools is needed. Overheating can occur for various reasons. In order to deal with the problem realistically, it is necessary to have the correct design benchmarks. The UK government has recently published new overheating guidelines for schools. A comparison is made between the existing and new overheating guidelines. This is based on an analysis of recorded temperature data from 140 classrooms in 18 naturally ventilated primary schools in London, UK, which is then compared with records of occupants' thermal comfort responses to indoor temperature. It was found that the old guidelines were too lenient, thereby allowing some overheating to occur. The new guideline is more stringent, but needs further development to reflect occupants' perceptions more accurately. Le fait d'assurer le confort thermique dans les écoles a un impact significatif sur les performances et la santé des élèves. Le changement climatique peut entraîner un risque accru de surchauffe. Il est nécessaire d'avoir une compréhension et une définition claires des excès de chaleur dans les écoles. Les surchauffes peuvent se produire pour différentes raisons. Afin de pouvoir traiter ce problème de manière réaliste, il est nécessaire de disposer des référentiels de conception corrects. Le gouvernement britannique a publié récemment de nouvelles directives contre les excès de chaleur destinées aux écoles. Il est procédé à une comparaison entre les directives existantes et nouvelles contre les excès de chaleur. Celle-ci est basée sur une analyse des données de température enregistrées dans 140 salles de classe de 18 écoles primaires à ventilation naturelle de Londres, au Royaume-Uni, qui a ensuite été comparée aux dossiers des réactions à la température intérieure éprouvées par les occupants en termes de confort thermique. Il a été constaté que les anciennes directives étaient trop laxistes, permettant ainsi que se produisent des surchauffes. La nouvelle directive est plus rigoureuse, mais a besoin d'être améliorée de manière à refléter avec plus de précision les perceptions des occupants. Mots clés:confort thermique adaptatif, référentiels, surchauffe, directive contre les excès de chaleur, salles de classe, référentiel thermique [ABSTRACT FROM AUTHOR]