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In cities with high density, heat is often trapped between buildings which increases the frequency and intensity of heat events. Researchers have focused on developing strategies to mitigate the negative impacts of heat in cities. Adopting green infrastructure and cooling pavements are some of the many ways to promote thermal comfort against heat. The purpose of this study is to improve microclimate conditions and thermal comfort levels in high-density living conditions in Seoul, South Korea.

This study compares six design alternatives of an apartment complex with different paving and planting systems. It also examines the thermal outcome of the alternatives under normal and extreme heat conditions to suggest strategies to secure acceptable thermal comfort levels for the inhabitants. Each alternative is analyzed using ENVI-met, a software program that simulates microclimate conditions and thermal comfort features based on relationships among buildings, vegetation and pavements.

The results indicate that grass paving was more effective than stone paving in lowering air temperature and improving thermal comfort at the near-surface level. Coniferous trees were found to be more effective than broadleaf trees in reducing temperature. Thermal comfort levels were most improved when coniferous trees were planted in paired settings.

Landscape elements show promise for the improvement of thermal conditions because it is much easier to redesign landscape elements, such as paving or planting, than to change fixed urban elements like buildings and roads. The results identified the potential of landscape design for improving microclimate and thermal comfort in urban residential complexes.

The results contribute to the literature by examining the effect of tree species and layout on thermal comfort levels, which has been rarely investigated in previous studies.

Maintaining a comfortable physical environment in the workplace is claimed to be vital as it will create a “healthier” building with optimum environmental conditions, which enable employees to be healthier and have a lower absenteeism rate, and hence be more productive. Thus, the purpose of this paper is to deal with the importance of physical environment comfort in the office workplace. Evaluation was made of the office workers’ performance that is mainly affected by levels of comfort in the office.

Three selected case studies were evaluated based on aspects of employees’ comfort, perceived health and absenteeism rate, by considering the elements of physical comfort that consist of room temperature, relative humidity and luminance level. The selected case studies were the Department of Development and Estate Maintenance of three research universities in Malaysia. Field studies were carried out using hygrometers and lux meters in measuring the said elements as well as post-occupancy evaluation, which involved 30 respondents for each case (total 90 respondents), to determine their perception of comfort and its effect on their health and absenteeism rate. Data collected were analysed using Statistical Package for the Social Sciences.

The results suggest that employees did not find luminance level uncomfortable, when compared with room temperature, thus proving that employees are more sensitive to room temperature comfort. Furthermore, when the room temperature comfort was low, significant correlations were found with health-related issues such as feeling “stuffy”, being easily tired and having difficulty concentrating.

This paper investigates the relationship between employee performance and a comfortable workplace environment. It could be concluded that an uncomfortable environment in an office workplace leads to health-related issues as well as increasing the absenteeism rate. High levels of employee absenteeism lead to decreased employee productivity, therefore affecting their work performance.

The study investigates the relationship between hospital environmental factors and the well-being of geriatric in-patients. It aims to identify the impact of architectural design on comfort, safety, privacy and stress levels experienced by elderly patients during their hospital stays.

Employing a mixed-methods approach, the research assesses the experiences of 100 geriatric in-patients across various hospital types through surveys, observational checklists and state anxiety measurements. The methodology involves examining architectural features, patient perceptions and correlations among environmental variables and patient experiences. Statistical analyses, including correlations and chi-square tests, were employed to discern associations between environmental variables and patient experiences.

The research identified key architectural features significantly impacting geriatric patients' experiences. Factors such as sturdy beds, furniture quantity, lighting conditions, proximity to facilities and ward occupancy levels were found to influence spatial, sensory and social comfort. Notably, proximity to facilities and control over the immediate environment were crucial for self-control and safety perceptions. Privacy, highly valued by patients, correlated with the presence of curtains and ward occupancy. Moreover, patient stress levels exhibited correlations with autonomy, privacy and ward occupancy.

This research offers significant insights into the criticality of specific architectural elements in enhancing comfort and reducing stress for geriatric in-patients. These findings hold substantial value for healthcare facility design, emphasizing the need to prioritize certain design aspects to promote the well-being of elderly patients during hospitalization.

As suggested in many previous studies, good thermal comfort and indoor air quality (IAQ) played a significant role in ensuring human comfort, health and productivity in buildings. Hence, this study aims to evaluate the thermal comfort and IAQ conditions of open-plan office areas within a green-certified campus building through a post occupancy evaluation.

Using the field measurement method, environmental dataloggers were positioned at three office areas during office hours to measure the levels of thermal comfort parameters, CO2 concentrations and the supply air rates. At the same time, questionnaires were distributed to the available office staff to obtain their perception of the indoor environment. The findings were then compared with the recommended environmental comfort ranges and used to calculate the thermal comfort indices.

Results show that the physical parameters were generally within acceptable ranges of a local guideline. The neutral temperature based on the actual mean vote at these areas was 23.9°C, which is slightly lower than the predicted thermal neutrality of 25.2°C. From the surveyed findings, about 81% of the occupants found their thermal environment comfortable with high adaptation rates. A preference for cooler environments was found among the workers. Meanwhile, the air quality was perceived to be clean by a majority of the respondents, and the mean ventilation rate per person was identified to be sufficient.

This study focussed on the thermal environment and air quality at selected office spaces only. More work should be carried out in other regularly occupied workplaces and study areas of the green educational building to allow a more thorough analysis of the indoor air conditions.

This paper highlights on the thermal comfort and air quality conditions of the air-conditioned office spaces in a green-certified campus building and is intended to assist the building services engineers in effective air conditioning control. The findings reported are useful for thermal comfort, IAQ and subsequently energy efficiency improvements in such building type where adjustments on the air temperature set-point can be considered according to the actual requirements. This study will be extended to other green campus spaces for a more exhaustive analysis of the indoor environment.

There is limited information pertaining to the environmental comfort levels in offices of green campus in the tropics. This study is, therefore, one of the earliest attempts to directly explore the thermal comfort and IAQ conditions in such workplace using both on-site physical measurement and questionnaire survey.

The purpose of this paper is to analyse the thermal environment of two engineering testing centres cooled via different means using computational fluid dynamics (CFD), focussing on the indoor temperature and air movement. This computational technique has been used in the analysis of thermal environment in buildings where the profiles of thermal comfort parameters, such as air temperature and velocity, are studied.

A pilot survey was conducted at two engineering testing centres – a passively cooled workshop and an air-conditioned laboratory. Electronic sensors were used in addition to building design documentation to collect the required information for the CFD model–based prediction of air temperature and velocity distribution patterns for the laboratory and workshop. In the models, both laboratory and workshop were presumed to be fully occupied. The predictions were then compared to empirical data that were obtained from field measurements. Operative temperature and predicted mean vote (PMV)–predicted percentage dissatisfied (PPD) indices were calculated in each case in order to predict thermal comfort levels.

The simulated results indicated that the mean air temperatures of 21.5°C and 32.4°C in the laboratory and workshop, respectively, were in excess of the recommended thermal comfort ranges specified in MS1525, a local energy efficiency guideline for non-residential buildings. However, air velocities above 0.3 m/s were predicted in the two testing facilities, which would be acceptable to most occupants. Based on the calculated PMV derived from the CFD predictions, the thermal sensation of users of the air-conditioned laboratory was predicted as −1.7 where a “slightly cool” thermal experience would prevail, but machinery operators in the workshop would find their thermal environment too warm with an overall sensation score of 2.4. A comparison of the simulated and empirical results showed that the air temperatures were in good agreement with a percentage of difference below 2%. However, the level of correlation was not replicated for the air velocity results, owing to uncertainties in the selected boundary conditions, which was due to limitations in the measuring instrumentation used.

Due to the varying designs, the simulated results of this study are only applicable to laboratory and workshop facilities located in the tropics.

The results of this study will enable building services and air-conditioning engineers, especially those who are in charge of the air-conditioning and mechanical ventilation (ACMV) system design and maintenance to have a better understanding of the thermal environment and comfort conditions in the testing facilities, leading to a more effective technical and managerial planning for an optimised thermal comfort management. The method of this work can be extended to the development of CFD models for other testing facilities in educational institutions.

The findings of this work are particularly useful for both industry and academia as the indoor environment of real engineering testing facilities were simulated and analysed. Students and staff in the higher educational institutions would benefit from the improved thermal comfort conditions in these facilities.

For the time being, CFD studies have been carried out to evaluate thermal comfort conditions in various building spaces. However, the information of thermal comfort in the engineering testing centres, of particular those in the hot–humid region are scantily available. The outcomes of this simulation work showed the usefulness of CFD in assisting the management of such facilities not only in the design of efficient ACMV systems but also in enhancing indoor thermal comfort.

University students spend a considerable amount of time in dorm rooms, where their environmental condition affects residents' health, well-being, sleep quality and the associated performance. Accordingly, this study aims to run an initial assessment of the environmental quality of two dormitory buildings in Tehran, using field studies and computational simulation, and then provide feasible optimized improvement strategies. The possible correlation between architectural elements and the environmental quality and the impact of proposed solutions on the annual energy use of these spaces are also discussed.

Field studies and computational simulation.

Results indicate that applied strategies, including shadings, reflectors, thermal and acoustic insulations, inlet vents and ceiling fans, can boost different aspects of the thermal condition, ventilation, acoustics and visual comfort by 21.77, 55.96, 20.69 and 50.37%, respectively. Accordingly, an acceptable comfort level can simply be achieved at a low cost by installing or replacing a few construction elements in dorm rooms. Nevertheless, a systematic architectural design can offer healthy spaces. For instance, south-facing rooms with large windows provide a higher level of thermal comfort and daylight quality.

This study shows that an acceptable level of IEQ can be achieved in dorm rooms by applying simple retrofit strategies. Moreover, energy consumption of dormitories can be significantly reduced using these solutions. However, the efficiency of the strategies in comparison to their economic aspects should be discussed, and results need to be further validated in real conditions. It is also recommended that a more extensive range of dormitory room typologies be studied in future studies. The results of this study are limited to the study context and so they can only be applied in case studies with similar use and climatic condition.

While many studies have explored the environmental quality of dormitories in different climatic conditions, no significant work has been found in Iran, Tehran investigating feasible optimized improvement strategies responding to all IEQ aspects of acoustics, thermal comfort, air and visual quality. Accordingly, this study makes an initial assessment of IEQ factors in a typical dormitory complex, and then develops practical retrofit strategies to bring the environmental condition of these spaces close to the suggested standards.

This study aims to examine the awareness of the inhabitants regarding energy consumption in relation to comfort in Tlemcen and analyze the paths of influence and the effects of individual objective and subjective characteristic factors. This determines the factors' level of perception of the importance of energy retrofitting.

As part of an exploratory empirical study, this paper further discusses accompanied survey data from a sample of 208 properties, through a triangulation of in-depth qualitative studies and quantitative studies developed and analyzed by SPSS software (the Statistical Package for the Social Sciences).

Analysis of the results of the survey shows that the respondents have a level of awareness on comfort linked to energy savings but they lack guidance and recourse to specialists. The conclusion is that resident awareness is crucial and beneficial and that the key socio-demographic characteristics to determine the perception factors are related to age, occupation, household size and time lived in the house.

By exploring some of the key insights from the survey, this research improves residents' perception of the importance of energy retrofitting in the residential sector, highlighting the importance of priorities. This influences public attitudes and contributes to raising awareness in order to provide useful results for developing, in future studies, motivational strategies for these inhabitants. The present research is expected to add value to existing studies academically and methodologically and provide policy guidance to policy makers and other energy efficiency (EE) practitioners in the Maghreb region and beyond.

The Purpose of this paper is to identify statistical relationships between visual environment and occupant productivity. Visual environment is one of the most important indoor environmental quality (IEQ) parameters, and it directly impacts occupant productivity in offices. The literature outlines the significance of the impact. Still, there is a lack of investigation, statistical analysis and inter-relationships between the independent variables (IEQ factors), especially in the hot and arid climate.

This study presents a research study investigating the effects and shows statistical relationships between IEQ on occupant comfort and productivity. The study was conducted in the Middle East, and data was collected for 12 months. It used the response surface analysis to perform analysis.

This study outlined seven unique relationships highlighting the recommended range, inter-dependencies. Results include that illumination has maximum effect on visual comfort and temperature, daylight having direct influence and relative humidity, wall type next to the seat and kind of workspace also impact visual comfort and productivity. These findings would help to improve occupant comfort and productivity in office buildings. It is recommended to include results and recommendations on design guidelines for office buildings.

This study presents the unique effects of non-visual IEQ parameters on visual comfort and productivity. This investigation also provides a unique method to develop the statistical relationship between various indoor environmental factors and productivity in different contexts and buildings.

Traditional central courtyards have been advocated for being thermally efficient for hot-climate regions. However, exploring previous literature shows that it is not clear to what extent courtyards are truly thermally comfortable. This study determines the level of thermal comfort in residential courtyards in hot-climate regions, taking Baghdad as a case study.

This study develops a novel Courtyard Thermal Usability Index (CTUI) to quantify the ability of courtyards to provide thermal comfort to occupants. CTUI is the fraction of useable thermally comfortable hours in courtyards of the total occupation hours during a specific period. To operationalise CTUI, the research employs the Envi-met 4.2 simulation tool to determine the annual thermal conditions of 360 courtyards. An adaptive thermal comfort model developed by Al-Hafith in 2020 for Iraq is used to judge simulated thermal conditions and determine CTUI.

CTUI enables determining the level of thermal comfort courtyards offer to occupants by showing the ratio of the thermally comfortable period versus the occupation period. Results show that, in Iraq, annually, courtyards offer up to 38% comfortable hours out of the total potential occupation hours. The rest of the time the courtyard will not be comfortable, mostly due to overheating. When designing courtyards, the most effective geometric property impacting courtyards' thermal conditions is width/height. The most important microclimatic factor impacting occupants' thermal sensation is mean radiant temperature (MRT). This study can be used to inform designing thermally efficient courtyards for hot-climate regions.

This study presents the first assessment of the thermal efficiency of courtyards in hot-climate regions depending on an assessment of their ability to provide thermal comfort to occupants. The study presents a novel index that can be used to quantify the ability of courtyards to provide a thermally comfortable environment to occupants.

From the 2000s onward, construction practices of urban residential buildings in China have shown a material transformation from clay brick to aerated concrete block. Moreover, the consumption of insulating materials for buildings has been increasing due to the new requirements in building energy-saving standards. This transformation and the increased consumption of insulating materials might have a vital impact on a building’s thermal comfort and its associated energy flows. Therefore, the purpose of this paper is to investigate the indoor thermal performance of urban residential buildings built with different materials and further discuss the correlations between indoor thermal comfort and the associated energy input.

This study investigated four residential buildings selected from four residential communities located in the cold climate zone of China. The Integrated Environment Solutions program was used to evaluate the thermal comfort levels and to quantify the operational energy consumption of the case study buildings. Additionally, the University of Bath’s Inventory of Carbon and Energy database was used to estimate the embodied energy consumption and CO₂ emissions.

The study found that materials transition and increasing consumption did not necessarily improve indoor thermal comfort. However, the materials transition has significantly decreased the embodied energy consumption of urban residential buildings. Furthermore, the increased utilization of insulating materials has also decreased the heating and cooling energy consumption. Therefore, overall, the environmental impacts of urban residential buildings have been reduced significantly.

In the future, residential buildings completed in the 1990s will need regular maintenance, such as adding insulation. Residential buildings completed based on the latest energy-saving requirements should optimize their ventilation design, for example, by increasing the ventilation rate and by reducing solar heat gains in the summer.

This paper investigates the effects of the materials change on thermal comfort levels and the environmental impacts of urban residential buildings in the cold climate zone of China, as these have not been the focus of many previous studies.