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1 – 10 of over 1000Salman Shooshtarian and Ian Ridley
Assessment of outdoor thermal perception in urban spaces is of particular importance due to its financial, social and ecological consequences. Thermal perception includes…
Abstract
Purpose
Assessment of outdoor thermal perception in urban spaces is of particular importance due to its financial, social and ecological consequences. Thermal perception includes four elements: thermal sensation votes (TSV), thermal preference (Tpref), overall thermal comfort (Tc) and thermal acceptability (Taccept). Thermal acceptability can offer a benchmark that specifies the acceptable thermal range (ATR), which is useful for urban planners, designers, and bio-meteorologists. ATR, however, can be defined either using direct or indirect measures. The purpose of this paper is to investigate the validity of the indirect measures of ATR, which are most commonly used in outdoor thermal comfort assessments.
Design/methodology/approach
This study was conducted in the context of Melbourne, which has an oceanic temperate climate (Cfb). Three sites forming RMIT University City Campus (RUCC) were selected as the case studies, which were located in the heart of Melbourne Central Business District. A field survey was conducted in RUCC during three seasons, from November 2014 (Spring) to May 2015 (Autumn), which consisted of concurrent field measurements and questionnaire surveys from 9:00 a.m. to 5:00 p.m.
Findings
In total, 1,059 valid questionnaires were collected from the three sites of RUCC. The results of comparative analysis between the different measures of ATR determination showed that the various elements of thermal perceptions expressed the users’ thermal judgements in different ways. Therefore, it was found that the instruction recommended by the thermal comfort standards on the definition of ATR failed to provide an appropriate estimation of ATR for outdoor built environments. The ATR, defined using TSV, therefore, was revised by the direct measure of thermal acceptability. The resulting range showed broader limits in acceptable thermal conditions in RUCC outdoor spaces users. Lastly, the results suggest that in the absence of directly measured acceptability of thermal conditions in field surveys, overall comfort is the most appropriate indirect measure to use.
Originality/value
Some indoor thermal comfort studies have used the alternatives for defining ATR. However, as the applicability of these four methods is yet to be fully explored in outdoor conditions with large weather variations, it is valuable to conduct a comparative analysis among these methods. This study also intended to understand the dynamics of comfort range under non-steady and non-uniform outdoor conditions. The resultant outcome has provided information on the relationship between different measures of thermal perceptions. Ultimately, this research aimed to explore the extent to which the indirect measures of acceptability are considered as a reliable source of information compared to the direct measure.
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Wafa Ghaffour, Mohammed Nabil Ouissi and Marc André Velay Dabat
The preservation of historic urban centres prevents anarchic development of the city and ensures a harmonious evolution of the urban form. It also improves the quality of…
Abstract
Purpose
The preservation of historic urban centres prevents anarchic development of the city and ensures a harmonious evolution of the urban form. It also improves the quality of life in the context of climate and environmental change. Morphological and geometric indicators of the urban fabric are key parameters in the formation of external microclimates. They provide a positive effect on the thermal comfort of pedestrians. The objective of this work is to study the impact of the site morphology on the external microclimate and to understand the relationship between the subjective perception and the objective quantification of the thermal environment. The result of this study has allowed us to propose solutions for the creation of a microclimate favourable to the appropriation of outdoor spaces. The authors finally propose guidelines for the design and rehabilitation of the historic site based on the establishment of links between the site's configuration, microclimatic conditions and users' perceptions.
Design/methodology/approach
Part of this study included the analysis of the microclimate of the historic “Bab El Hadid” district of the City of Tlemcen, by developing a questionnaire survey and a numerical simulation validated by measurements of the microclimate the authors made on site. To complete this task, the authors applied the Envi-met 4.1 model during the coldest month of the winter and the hottest month of the summer. Urban parameters are represented at different measurement points characterised by a variability of the sky view factor (SVF).
Findings
The results presented in terms of average expected the predicted mean vote (PMV) voting, solar access and air temperature. They show that thermal conditions are directly related to the SVF, the height/width ratio (H/L) of streets as well as the orientation of urban canyons. The points located in the streets facing North–South, present an acceptable performance. Streets shaded by trees with a canyon aspect ratio of between 1.18 and 1.70 reduce heat stress in outdoor spaces. The PMV models discussed provide information on the most appropriate locations for pedestrians. The authors have proposed urban orientations that could limit unfavourable conditions in outdoor spaces. They are useful for architects and urban planners in the design and rehabilitation of historic centres.
Originality/value
In Tlemcen, the microclimate is not taken into account in the design and rehabilitation of urban fabrics. For this specific purpose, the authors want to stress in the research the importance of safeguarding urban heritage through the renewal of the old city and the bioclimatic rehabilitation of its urban spaces.
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Nur Dalilah Dahlan, Amirhosein Ghaffarianhoseini and Norhaslina Hassan
Recent studies have found that the high demand for air-conditioning usage in tropical countries has affected the thermal adaptability of building occupants to hot weather…
Abstract
Purpose
Recent studies have found that the high demand for air-conditioning usage in tropical countries has affected the thermal adaptability of building occupants to hot weather, and increased building energy consumption. This pilot study aims to investigate the effects of transient thermal environment changes on participants' sensory and physiological responses.
Design/methodology/approach
The change of thermal perceptions, skin temperatures and core temperatures when exposed to transient thermal environments (cool-warm-cool) from 10 college-aged female participants during a simulated daily commute by foot to class in a tropical university campus were investigated. Subjective measurements were collected in real-time every 5 min.
Findings
The main finding suggests that participants were acclimatised to cool air-conditioned indoor environments, despite exhibiting significant mean skin temperature differences (p < 0.05). In addition, exposure to uniform air conditioning from 17 to 18°C for 20 min was thermally unacceptable and reduced concentration during given tasks.
Research limitations/implications
The study focused on thermal comfort conditions in a uniform air-conditioned lecture hall, and the findings may not be applicable for residential and other private building spaces. The distinct temperature difference between indoor and outdoor in the tropical built environment resulted in high dependence on air-conditioning usage. The building occupants' well-being and energy conservation implications of the findings are discussed.
Practical implications
This study provides the platform for discussion on the dynamics of occupants' comfort level and adopting a more variable thermal environment in tropical spatial transient thermal environments among architects and building management system managers. The findings from this study may contribute to the Malaysian Standards for Energy Efficiency and Use of Renewable Energy for Non-Residential Buildings (MS1525).
Originality/value
A knowledge gap in adaptive thermal comfort due to exposure from transient conditions in tropical university campus for energy efficiency revision has been investigated.
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The paper aims to determine the thermal comfort perception of schoolchildren from a warm and humid environment. There is a concern about the effect of high temperature on…
Abstract
Purpose
The paper aims to determine the thermal comfort perception of schoolchildren from a warm and humid environment. There is a concern about the effect of high temperature on the health and academic performance of schoolchildren.
Design/methodology/approach
Objective and subjective methodological approaches were adopted to collect data during the fieldwork in the selected primary schools. ASHRAE adaptive comfort model was adopted to analyze the data.
Findings
The paper provided empirical results about the comfort requirements of schoolchildren from the warm and humid environment. During the occupied school time, the studied schoolchildren were found to tolerate temperatures higher than the upper limit temperature recommended by ASHRAE Standard 55. The paper recommends that the studied children may not need any active ventilator to be thermally comfortable during the occupied school hours
Originality/value
The paper found the range of temperatures that schoolchildren from the warm and humid environment can adapt to. The information may be useful to architects, engineers and facility managers
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Meshack O. Efeoma and Ola Uduku
The purpose of this paper is to adduce the most appropriate thermal comfort assessment method for determining human thermal comfort and energy efficient temperature…
Abstract
Purpose
The purpose of this paper is to adduce the most appropriate thermal comfort assessment method for determining human thermal comfort and energy efficient temperature control in office buildings in tropical West Africa.
Design/methodology/approach
This paper examines the Adaptive Thermal Comfort Standard, from its research evolution to its contemporary use as an environmental design assessment Standard. It compares the adaptive component of ASHRAE Standard 55 and the European CEN/EN 15251. It begins by reviewing relevant literature and then produces a comparative analysis of the two standards, before suggesting the most appropriate Adaptive Thermal Comfort Standard for use in assessing conditions in tropical climate conditions. The suggested Standard was then used to analyse data collected from the author's pilot research into thermal conditions, in five office buildings situated in the city of Enugu, South Eastern Nigeria.
Findings
The paper provides insight as to why the ASHRAE adaptive model is more suitable for thermal comfort assessment of office buildings in the tropical West African climate. This was demonstrated by using the ASHRAE Thermal Comfort Standard to assess comfort conditions from pilot research study data collected on Nigerian office buildings by the author.
Originality/value
The paper compares the adaptive component of ASHRAE Standard 55 with CEN/EN 15251, and their different benefits for use in tropical climates. It suggested the need for further research studies and application of the ASHRAE Adaptive Thermal Comfort Standard in the tropical West African climate.
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The heating, ventilation and air conditioning systems are responsible for a significant proportion of the energy consumption of the built environment, on which the…
Abstract
Purpose
The heating, ventilation and air conditioning systems are responsible for a significant proportion of the energy consumption of the built environment, on which the occupant's pursuit of thermal comfort has a substantial impact. Regarding this concern, current software can assess and visualize the conditions. However; integration of existing technologies and real-time information could enhance the potential of the solution proposals. Therefore, the purpose of this research is to explore new possibilities of how to upgrade building information modeling (BIM) technology to be interactive; by using existing BIM data during the occupation phase. Moreover, the research discusses the potential of enhancing energy efficiency and comfort maximization together by using the existing BIM database and real-time information concomitantly.
Design/methodology/approach
The platform is developed by designing and testing via prototyping method thanks to Internet of things technologies. The algorithm of the prototype uses real-time indoor thermal information and real-time weather information together with user's body temperature. Moreover, the platform processes the thermal values with specific material information from the existing BIM file. The final prototype is tested by a case study model.
Findings
The outcome of the study, “Symbiotic Data Platform” is an occupant-operated tool, that has a hardware, software and unique Revit-Dynamo definition that implies to all BIM files.
Originality/value
The paper explains the development of “Symbiotic Data Platform”, which presents an interactive phase for BIM, as creating a possibility to use the existing BIM database and real-time values during the occupation phase, which is operated by the occupants of the building; without requiring any prior knowledge upon any of the BIM software or IoT technology.
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This paper aims to investigate the thermal comfort practices in four non-domestic buildings and explores how the organisational context affects the actions and practices…
Abstract
Purpose
This paper aims to investigate the thermal comfort practices in four non-domestic buildings and explores how the organisational context affects the actions and practices of occupants and facilities managers.
Design/methodology/approach
The study applied qualitative methods and post-occupancy evaluation methodologies to investigate the thermal practices in four case studies. A combination of qualitative and quantitative methodologies was deployed, namely, semi-structured interviews, questionnaires, observation and monitoring studies of building performance.
Findings
The concept “distributed agency” was applied to analyse the thermal comfort practices in non-domestic buildings. This concept helped to illustrate everyday actions by occupants and facilities managers in relation to the organisational context. Occupants’ actions and building management practices could be affected by the organisation norms and context leading to problems and dissatisfaction with indoor thermal conditions.
Research limitations/implications
This study is based on a small number of case studies and it is exploratory. Extensive monitoring data were not available. However, the research identified the thermal conditions and occupants’ satisfaction levels as background where actions to achieve thermal comfort and facilities manager’s practices took place.
Practical implications
The study suggests the need to examine in greater depth how the organisational goals and individual goals could be linked to support specific building performance targets.
Social implications
The paper advocates for the application of multidisciplinary approaches to study the occupant dimension of building performance. It suggests the need to develop a nuanced understanding of how occupants pursue comfort as active agents who interact with the built environment.
Originality/value
The study has applied social practice theory to consider the influence of the organisation on thermal comfort practices in non-domestic buildings; considering the perspectives of building occupants and facilities managements within the organisational context.
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Intan Nadirah Mohd Yusof, Mohd Rozi Ahmad, Nur Ain Yusof, Mohamad Faizul Yahya, Ibiwani Alisa Hussain, Raja Mohammed Firhad Raja Azidin and Ahmad Munir Che Muhamed
The purpose of this paper is to investigate the perceived thermal comfort experienced by active Muslim women (AMW) wearing hijabs determined by their experience of comfort…
Abstract
Purpose
The purpose of this paper is to investigate the perceived thermal comfort experienced by active Muslim women (AMW) wearing hijabs determined by their experience of comfort sensation while doing sports activities or regular exercises. This study also examines whether the casual hijabs which are widely used among AMW are able to supply the appropriate comfort for active purposes.
Design/methodology/approach
This study used the quantitative method using survey questionnaires to collect 100 primary data obtained from AMW respondents who are university students located around the Klang Valley region in Malaysia.
Findings
Based on the overall results, this study suggests that the common hijabs that are used for casual applications do not offer sufficient comfort to Muslim women while performing sports activities or regular exercises.
Research limitations/implications
The outcome of this study will help to gain a better understanding on hijab preferences and comfort experienced from the viewpoint of regular hijab users. The information will assist industries to consider the selection of the right materials when developing sportswear hijabs to provide better comfort for more AMW in the near future. The method used in this study is useful to gain information on consumer’s profile and value-added details about the discomfort aspects of hijab which are scarce in the existing literature on thermal comfort.
Originality/value
This study was conducted to explore the type of hijabs commonly worn by AMW while performing sports activities and to obtain their views on the perceived thermal comfort.
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Christian Koranteng, Barbara Simons and Charles Essel
The ever-increasing demand and consumption of energy and the effects of global warming with its long-term comrade, climate change, is obvious today than ever before. In…
Abstract
Purpose
The ever-increasing demand and consumption of energy and the effects of global warming with its long-term comrade, climate change, is obvious today than ever before. In today’s world, naturally-ventilated buildings hardly provide the satisfaction that occupants need and wish for. It’s on this backdrop that the study aims to investigate how responsive buildings on the Kwame Nkrumah University of Science and Technology, Kumasi, Ghana campus are to its warm humid climate and assess students thermal comfort levels.
Design/methodology/approach
Quantitative approach was adopted for the study. Empirical investigation was carried out using the survey approach. In total, 14 buildings (offices, classrooms and halls of residences) were assessed using the Mahoney Tables. Again, subjective thermal perceptions of occupants in the halls of residences was sought. A total of 214 valid questionnaires were used for the analysis.
Findings
Adaptive principles like the Mahoney Tables are not followed in recent years. Even where these principles have been followed, indoor spaces were still found to be uncomfortable. In total, 58 per cent of the occupants in all the three halls of residence voted in the comfort band: an indication unacceptable sensations. Warm sensation votes (44 per cent) was more than cool sensation votes (29 per cent). In warm sensation, 39 per cent of the subjects preferred cooler environment. The occupants felt that opening windows and the use of fans could keep them comfortable. Moreover, 48 per cent of the subjects voted that their fans and windows were effective.
Originality/value
The papers contribution to the body of knowledge is the provision of empirical evidence in the field of adaptive designs and thermal comfort. There is a strong indication from the results that human activities in terms of blatant disregard for laid down design principles coupled with the worsening situation of global warming is making interior spaces ever uncomfortable.
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The aims of this paper is to investigate the overall satisfaction of occupants of green and conventional residential buildings and their perception of indoor environment…
Abstract
Purpose
The aims of this paper is to investigate the overall satisfaction of occupants of green and conventional residential buildings and their perception of indoor environment quality (IEQ) and to study factors that may cause occupants’ dissatisfaction.
Design/methodology/approach
Data were collected through a survey sent to occupants of comparable green and conventional multi-family buildings. The difference in responses between occupants of green and conventional buildings was analysed using Mann–Whitney (rank sum) test. The ordered logistic models were applied to the data to test whether the overall satisfaction changes depending on the level of acceptance of indoor environment quality and whether the building environmental profile and the apartment tenure affect occupant satisfaction.
Findings
The results show that both categories of occupants are very satisfied with their apartments and that there is no statistically significant difference between the stated overall satisfaction of occupants living in green and conventional buildings, although a difference was found in the acceptance level for thermal and sound quality. The research highlights the importance of occupant feedback, user-friendly technical installations and the ability to control indoor environment. This knowledge is important for designers, engineers and developers alike in enabling them to improve dwelling quality and minimize post-occupancy problems.
Research limitations/implications
It was not possible to include physical measurements of IEQ parameters; the analysis is based only on occupants’ responses, which may carry a certain subjectivity.
Originality/value
The paper contributes to the understanding of IEQ from occupant perspective and to knowledge on green building performance.
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