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Passive design strategies enhance indoor thermal comfort and reduce energy consumption in buildings located in hot climates. Thus, exploring the various zones of a house's yard can yield valuable insights for devising a plan that achieves high energy and lighting efficiency. This study examines the climate-responsive design strategies of 20 traditional courtyard buildings in Birjand's hot and dry climate. These courtyard houses informed modelling a new hypothetical house in DesignBuilder. Two main orientations (45° = NE–SW, and 315° = NW–SE) were used for comparing their impact on indoor air temperature, solar gain and daylight factor across various courtyard zones. The findings indicate that during winter, the interiors of courtyard houses maintain a temperature higher than the exterior, while in summer, they remain cooler than outside conditions. Concerning the influence of orientation on indoor climates, the NE–SW orientation yielded the greatest solar gains for windows in the northern and western zones. Conversely, in the NW–SE orientation, the most substantial solar gains were recorded for windows in the northern and eastern zones. Additionally, the study noted a marginal variation in the daylight factor across different zones of the courtyard houses when comparing the two orientations. [ABSTRACT FROM AUTHOR]

Thermal comfort in schools affects children's wellbeing and educational outcomes. Global warming and frequent heatwaves have worsened the overheating issue in schools, especially in Western European countries, like the UK. While previous studies have mainly focused on residential and commercial buildings, school-related research often emphasised indoor thermal conditions, neglecting the broader influence of microclimates on the overall thermal conditions. Therefore, this research explores the thermal conditions in schools, during the summer of 2023, with a specific focus on the impact of greenery and materials. Urban Greening Factor (UGF) and its relationship with indoor and outdoor air temperatures were explored for the first time. Field studies were conducted in four primary schools in Coventry, UK, measuring indoor air temperatures and micrometeorological parameters. Tree shade demonstrated a substantial cooling effect, reducing air temperature and mean radiant temperature by up to 6.4 °C and 22.9 °C, respectively. Considerable difference between measured air temperatures in sunlight and official meteorological records highlights the need for microclimatic studies in schools. Thermal imagery identified high surface temperatures on artificial grass (67 °C) and asphalt (55 °C). Urban Greening Factor showed a strong correlation with classroom temperatures but failed to account for spatial greenery distribution and subsequently outdoor thermal conditions. The study concludes that optimising tree shade and replacing dark and artificial materials, are necessary for effective heat mitigation, offering valuable insights for policymakers and urban planners to create thermally comfortable and sustainable school environments. • Urban Greening Factor is not correlated with outdoor thermal conditions. • Artificial grass surface temperature is 30 °C higher than natural grass. • The school in the most deprived area has the most asphalt and artificial grass. [ABSTRACT FROM AUTHOR]

• The rural heat island effect of centralized rural residences was identified. • The courtyard with a south wing performs better in mitigating heat stress. • The effectiveness of localized mitigation measures was assessed. • Fabric shade measure can reduce extreme heat stress duration by 2 h. • PV modules can lower t mrt by 13 °C and 23 %−28 % daily energy demand. China has implemented a Centralized Rural Policy since 2004 to enhance energy efficiency. However, this has led to the potential creation of a Rural Heat Island (RHI) effect, which could diminish outdoor thermal comfort and increase building energy consumption during hot summers. While most studies on heat island effect focus on spatiotemporal variations and heat mitigation measures, there is limited research on rural areas, particularly the special layout of rural residences. Additionally, most studies only consider the outdoor environment, overlooking indoor thermal comfort and building energy consumption. Therefore, in order to investigate the RHI effect and assess the efficacy of localized heat mitigation measures, this study analyzed 22 types of courtyard layout patterns in a typical centralized village in northern China through detailed field measurements and performance simulations. The results show an obvious heat island effect in the rural centralized residences, where residential zones recorded average temperatures of 1.6 °C higher than those of rural boundaries. Courtyards featuring a south wing significantly alleviated outdoor thermal stress, reducing the discomfort time of extreme Physiological Equivalent Temperature (PET) by 1.5 h compared to those courtyards with a wall. Among the four localized heat mitigation measures examined, the featured black fabric shade performs best for its effectiveness in mitigating outdoor thermal stress, capable of reducing the courtyard's maximum Mean Radiant Temperature (T mrt) by 21.5 °C and decreasing the duration of extreme PET by 2 h. Photovoltaic modules installed on the roof not only generate energy but also alleviate outdoor thermal stress, reducing the maximum T mrt by 12.9 °C and lowering 23 % to 28 % daily energy demand, making them highly suitable for deployment in rural areas with high rates of energy poverty. The simulated results indicate that these localized heat mitigation measures mutually reinforce each other in reducing the RHI effect. The combination of four heat mitigation measures can reduce PET by up to 20 % and EUI by up to 44 % compared to the original courtyard. Incorporating these localized strategies into planning practice enables rural planners and policymakers to develop effective interventions against the RHI effect. [ABSTRACT FROM AUTHOR]

Thermal comfort in cities is an influential factor for citizens' wellbeing and life quality. Urban microclimate studies have gained popularity following increasing urbanization trends and global climate change in recent years. Urban fabric and morphology in traditional cities represent a unique pattern both spatially and climatically. However, few studies have investigated traditional cities' urban thermal comfort conditions. Therefore, this study aimed to assess the thermal comfort in different subspaces of Algiers Casbah's historic urban fabric, which falls in the hot Mediterranean climate (Csa). This research evaluated the human thermal sensation by applying the physiological equivalent temperature (PET) index. The methodology used was a mixed approach, including field measurements, calculations, and a survey questionnaire. The results indicate the presence of a high-stress level during the measurement periods, and notable differences between the subspaces in January (ΔPETMax.Jan = 3.7 °C) and August (ΔPETMax.Aug = 2.2 °C). The highest discomfort was recorded in spaces with collapsed buildings, especially during the hot hours of the day. The findings also highlight a strong impact of the sky view factor on the mean radiant temperature (Tmrt) and the physiological equivalent temperature (PET). The study discusses recommendations and ways to improve the design of outdoor spaces and relieve heat stress in the streets of traditional cities. Finally, this work helps urban managers and heritage conservators in urban rehabilitation policies concerning outdoor microclimate improvement. [ABSTRACT FROM AUTHOR]

Impacts of the laminar airflow ventilation system design factors on contaminant removal and thermal comfort condition in an operating room have been investigated by means of Lagrangian-based particle transport using the non-Boussinesq modeling of the buoyancy effects. An operating room including staffs and a patient with realistic human geometries and two surgery lights are included in simulations. The laminar airflow system is placed on the ceiling with a surrounding fixed-height partial wall and the air barrier supply grills. Effects of density change in mixed convection flow regime are included by the non-Boussinesq modeling of the exact air density variation. The predicted mean vote, the age of air, the colony-forming units per cubic meter, the average temperature, the average velocity, the relative humidity, the density distribution, and the positions of particles are calculated to assess the indoor air ventilation quality. A total of 27 simulation cases have been considered to determine the impact of three main design factors including the laminar airflow system area, the supply air, and the air barrier velocities on the performance of the system. It is concluded that for the curtain velocity of 2 m/s, the thermal comfort reduces with increasing the laminar airflow velocity, but for the third staff, the results show that for small laminar airflow areas, the speed of the inlet port should be reduced and for the larger sizes, the inverse of this trend is recommended. Moreover, for all cases the humidity varies within the range of 55%–56%, which agrees well with the suggested standard humidity range between 50% and 60%. It is concluded that the cases of the laminar airflow velocity equal to 0.3 and 0.5 at the curtain velocity of 1 m/s are generally more appropriate than other cases due to less accommodation of particles near the entire body of the patient. [ABSTRACT FROM AUTHOR]

Highlights • The impact of land cover on microclimate and indoor thermal comfort was studied. • Maximum measured UHI in Manchester was 2.3 °C at 4:00. • Maximum cooling impact of the campus park was during the hottest hours of the day. • 17% more trees in the campus improved indoor thermal comfort by up to 20.8%. Abstract Higher air temperatures in large cities like Manchester, UK, reduce human thermal comfort. In this paper, the impact of land cover on microclimate, and consequently on indoor thermal comfort is studied. Through different stages, field measurements and computer modelling were carried out for a heat wave episode in summer 2017 in Manchester: First, the urban heat island (UHI) was measured between the city centre of Manchester and the campus of the University of Salford (between May to October 2017). Maximum detected UHI was 2.3 °C at 4:00, during the hottest day of the year. Parallel measurements within the university campus showed that the park was 0.9 °C cooler than the paved areas (maximum cooling effect was 3.6 °C at 14:45). Finally, the impact of the current land cover of the campus, and a greener land cover (as a renaturing scenario) with more planted trees on indoor thermal comfort of a house within the campus were studied. It was found that by adding 17% more trees to the campus, indoor thermal comfort was improved by 20.8% during the hottest day of 2017 in Manchester. These showed that renaturing cities could be a solution for future warmer climates. [ABSTRACT FROM AUTHOR]

The present study intended to evaluate thermal comfort conditions in microclimates of the urban historical areas of Isfahan, Iran during a heatwave. The thermal comfort conditions of different historical sites were compared during the daylight hours to determine the best time to visit each historical site. Using the results of this study, tourists can select the best timeframe with appropriate thermal conditions to visit the historical sites of Isfahan. Along with performing field measurements in the intended historical sites, a questionnaire was used to determine the thermal comfort range of tourists. ENVI-met is used in order to properly simulate the outdoor thermal environment of the historical touristic areas in Isfahan during the hottest as well as the most touristic month of the year. The results of questionnaire and simulations are compared with each other. It was shown that three historical sites with higher thermal stress experience an unpleasant thermal condition. The results of questionnaire show that the comfort range of tourists is within 23.06–29.73 °C PET. The thermal conditions of Si-o-Se Pol, Hasht Behesht and Naqsh-e-Jahan are within the thermal comfort range at 19,20 and 21 p.m. respectively. During the daytime, thermal comfort conditions varied from 4.9 °C PET at 8 a.m. to 8.1 °C PET at 3 p.m. Early morning hours were the most comfortable time to visit the historical sites of Menar-e-Jonban, Masjed-e-Jame and Vank Cathedral in Isfahan. During the peak hours of heat, the priority of thermal comfort goes to Masjed-e-Jame, Menar-e-Jonban and Si-o-Se Pol, respectively. [ABSTRACT FROM AUTHOR]

The growing interest in thermal comfort of outdoor environments yields in different analysis on courtyards as a common space between urban and architectural scales. However, there is a limited knowledge regarding the microclimatic behavior of such spaces. Using ENVI-met simulations, this paper aims to numerically discuss the thermal performance of different configurations of traditionally designed courtyards in Shiraz, Iran, which experiences hot summers and cold winters. The geometrical effects such as orientation and H/W (height to width ratio) of courtyards are considered as potential parameters to improve the microclimatic conditions. In this paper, PMV and UTCI are used as thermal comfort indices. The obtained results indicate mean radiant temperature and wind speed as the most effective parameters for thermal comfort of courtyards. In addition, the aforementioned geometrical parameters might not be able to solely create a desirable condition, but they could significantly improve the thermal comfort of courtyards during summer and winter. To achieve a desirable thermal comfort level, the results suggest using configurations of a high H/W rate and southward orientation in order to obtain better shading during summer as well as allowing the solar radiation in while regulating the wind speed in winter. [ABSTRACT FROM AUTHOR]

This paper discusses the effects of urban design and meteorological parameters on thermal comfort for pedestrians at street level. A comparison of different urban modifications allows an objective assessment of the effectiveness of climate adaptation measures. Because, these results are based on different measurement and modelling methods, they are given in various comfort indicators and studied in a specific urban context, climate and weather condition. This study presents the relative effects of design measures based on identical input parameters and one simulation method using the high resolution three-dimensional model ENVI-met and the thermal comfort index physiological equivalent temperature (PET). [ABSTRACT FROM AUTHOR]

Abstract: With increased global concerns on climate change, the need for innovative spaces which can provide thermal comfort and energy efficiency is also increasing. This paper analyses the effects of transitional spaces on energy performance and indoor thermal comfort of low-rise dwellings in the Netherlands, at present and projected in 2050. For this analysis the four climate scenarios for 2050 from the Royal Dutch Meteorological Institute (KNMI) were used. Including a courtyard within a Dutch terraced dwelling on the one hand showed an increase in annual heating energy demand but on the other hand a decrease in the number of summer discomfort hours. An atrium integrated into a Dutch terraced dwelling reduced the heating demand but increased the number of discomfort hours in summer. Analysing the monthly energy performance, comfort hours and the climate scenarios indicated that using an open courtyard May through October and an atrium, i.e. a covered courtyard, in the rest of the year establishes an optimum balance between energy use and summer comfort for the severest climate scenario. [Copyright &y& Elsevier]

Courtyard vegetation, high albedo surfaces, and courtyard ponds were investigated as potential heat mitigation strategies using field measurements and simulations in a university campus environment. The investigation was performed during a summer period in the temperate climate of Portland, Oregon, USA. In a comparison of seven locations on the campus, the maximum park cooling island effect recorded was 5.8 °C between the heavily treed campus park and a nearby parking lot with asphalt pavement. Simulations of courtyards with vegetation and a water pond showed 1.6 °C and 1.1 °C air temperature reduction, respectively. Changing the albedo of the pavement in a bare courtyard from 0.37 (black) to 0.91 (white) led to 2.9 °C increase of mean radiant temperature and 1.3 °C decrease of air temperature. [ABSTRACT FROM AUTHOR]

Highlights: [•] Single, linear and courtyard urban block layouts are simulated in the Netherlands. [•] Annual heating and lighting energy, and summer thermal comfort are studied. [•] The results demonstrate the importance of the surface-to-volume ratio. [•] The 3-storey courtyard layout uses 22% less energy compared to the one zone layout. [•] The 3-storey courtyard layout has 9% less discomfort hours than the one zone layout. [ABSTRACT FROM AUTHOR]

Abstract: Thermal comfort has been discussed since 1930s. There have been two main approaches to thermal comfort: the steady-state model and the adaptive model. The adaptive model is mainly based on the theory of the human body's adapting to its outdoor and indoor climate. In this paper, besides the steady-state model, three adaptive thermal comfort standards are comprehensively reviewed: the American ASHRAE 55-2010 standard, the European EN15251 standard, and the Dutch ATG guideline. Through a case study from the Netherlands, these standards are compared. The main differences discussed between the standards are the equations for upper and lower limits, reference temperatures, acceptable temperature ranges and databases. [Copyright &y& Elsevier]

• This paper studied thermal comfort within different urban canyons in a hot climate. • The role of urban geometry and shadings on pedestrian thermal comfort is investigated. • The outdoor thermal comfort range in Ahvaz is obtained within 19.6–30.9 °C PET. • PET reduction caused by shadings is more observed in EW canyons and wide canyons. • Shadings do not significantly affect the street sidewalk air temperature. This study investigated the role of urban geometry and urban shading in improving the pedestrians' thermal comfort in hot climate of Ahvaz, Iran. Six urban canyons are selected in Ahvaz. To determine the outdoor thermal comfort range, micrometeorological measurements and questionnaire survey were conducted in July 2018. ENVI-met is used to investigate the role of urban geometry and urban shadings. To evaluate the outdoor thermal comfort, physiologically equivalent temperature (PET) is calculated using RayMan. Using the results of the field studies, the outdoor thermal comfort range in Ahvaz is obtained within 19.6 °C to 30.9 °C PET. Simulation results show that the closer the canyon orientation is to the north-south direction, the lower the air temperature (T a) and mean radiant temperature (MRT) are. Also, by reducing the canyon aspect ratio, PET increases as well. Urban shadings decreased MRT and PET up to 34 °C and 17.6 °C, respectively. In contrast, shadings did not affect the air temperature, significantly. PET reduction caused by shadings is more notable in east-west canyons, as well as in wider canyons. MRT and PET in all cases are highly correlated to SVF. The observations showed no strong correlation between T a , relative humidity, and wind speed, with SVF in all canyons. [ABSTRACT FROM AUTHOR]

• High albedo materials were implemented on facades with different orientations. • Façade insolation, ground surface temperature, and surface energy balance were reported. • EW canyon receives 6 h of direct sun more than the NS canyon. • East and west cool facades led to the maximum net radiation reductions. • North and south facades had negligible contributions in reducing PET. Deploying solar reflective materials on urban surfaces is known as an effective heat mitigation strategy. Several studies have shown their cooling impacts; however, most of them have focused on rooftops rather than facades. The novelty of this paper is related to exploring the impact of each façade orientation on the corresponding microclimate and energy balance. High albedo materials were implemented on facades with different orientations to explore the potential of each façade. Computer simulations were employed to calculate the insolation of different façades, ground surface temperature, and surface energy balances. The simulations are done for the longest day of the year (21st of June) to have the maximum solar radiation on all facades. The results showed that east-west canyons receive 6 h more direct sun than north-south canyons. This proved that eastern and western facades have the most impact on the microclimate. Cooling east and west facades led to the maximum net radiation reductions for the ground surface. Furthermore, north and south facades had negligible contributions to pedestrian thermal comfort. By understanding the role of each façade, designers and policy makers could deploy cooling materials more effectively on building surfaces. [ABSTRACT FROM AUTHOR]

Thermal comfort is one of the main factors affecting pedestrian health, and improving thermal comfort enhances walkability. In this paper, the impact of various strategies on thermal-comfort improvement for pedestrians is thoroughly evaluated and compared. Review studies cover both fieldwork and simulation results. These strategies consist of shading (trees, buildings), the orientation and geometry of urban forms, vegetation, solar-reflective materials, and water bodies, which were investigated as the most effective ways to improve outdoor thermal comfort. Results showed that the most important climatic factors affecting outdoor thermal comfort are mean radiant temperature, wind speed, and wind direction in a microclimate. The best heat-mitigation strategy for improving thermal comfort was found to be vegetation and specifically trees because of their shading effect. The effect of height-to-width (H/W) ratio in canyons is another important factor. By increasing H/W ratio, the thermal-comfort level also increases. Deploying highly reflective materials in urban canyons is not recommended, as several studies showed that they could reflect solar radiation onto pedestrians. Results also showed that, in order to achieve a satisfactory level of thermal comfort, physiological and psychological factors should be considered together. [ABSTRACT FROM AUTHOR]

Courtyards have been traditionally used as a passive design strategy in desert climates. However, few studies have quantified the thermal performance of this building archetype. This paper explored the indoor and outdoor thermal conditions of a typical courtyard house in Iran. The study was performed in two phases. The first phase showed the effect of the position of the zones located in four sides of the courtyard on their indoor energy use and indoor thermal comfort. The results showed that the east and west sides of the courtyard require the highest cooling demand due to the solar radiation in summer time. Furthermore, maximum discomfort hours occurred in the east zone. In the second phase, hourly air temperature inside and outside of the courtyard were compared during the longest day of the year (21st of June). The results showed that inside of the courtyard was 1.2 °C cooler than the outside on average. Moreover, it was observed that the temperature fluctuations outside of the courtyard were higher than the inside. To sum up, the results showed that courtyards can provide a cooler microclimate in summer time. [ABSTRACT FROM AUTHOR]

The aim of this study was to understand the effect of urban street greenery type and arrangements on thermal comfort and heat stress in summer. Field measurements and computer simulations were carried out on East-West (E-W) and North-South (N-S) oriented streets in Isfahan, Iran. Through the field measurements in July 2014, 17 different streets were studied, followed by 15 perturbation scenarios (urban design alternatives) simulated by ENVI-met. The study showed that there is a significant and positive relationship between the Sky View Factor (SVF) and the Physiological Equivalent Temperature (PET) values. Comparison of the meteorological parameters within different street orientations showed that the effect of the SVF on the E-W streets was more significant than in N-S streets. Furthermore, greenery arrangement and building heights showed different impacts on the outdoor thermal comfort streets with different orientations. • The effect of different street greenery arrangements on thermal comfort was studied. • A significant positive relationship between SVF and PET was observed. • SVF of more than 0.6 leads to higher heat stress. • The effect of the SVF on the microclimate of E-W streets was more N-S. [ABSTRACT FROM AUTHOR]