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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.

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.

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.

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.

Buildings have a considerable impact on the environment being responsible for a substantial proportion of global energy consumption, thus contributing significantly to the anthropogenic CO2 emissions, which evidence suggests is the main cause of climate change. Mitigation and adaptation measures are required to tackle the challenges of climate change. Adaptive measures – structural and behavioural strategies – are the focus of this paper. Structural strategies include flexible and adaptive structural systems; while behavioural strategies cover the spatial, personal, and psychological control measures which may influence the design and operations of buildings. The study explores the adaptive thermal comfort of occupants and examines the design strategies for adapting buildings to climate change in the tropical context, with a view to determine the effectiveness of these strategies as observed in the case study. The study was conducted during the rainy and dry seasons in Abeokuta, Ogun State, Nigeria, located in a warm humid climate zone.

The Institute of Venture Design student hostel was used as case-study to conduct the survey on a sample of 40 respondents by means of structured questionnaire. The respondents' thermal sensation and access to thermal controls were determined, and their thermal sensation and thermal adaptability in both seasons comparatively analyzed. Indoor environmental parameters including air temperature, mean radiant temperature, relative humidity and air velocity were also measured. The data were analyzed using relevant descriptive and inferential statistics. The study discussed the effectiveness of design strategies available for building adaptation in an era of climate change within the warm humid environment, concluding on the need for greater synergy between the techno-structural and socio-behavioural dimensions of building adaptation.

Occupants dwelling in hot climatic regions of India for a longer term are tolerable to high temperature levels than predicted by American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) standards. The purpose of this study is to evaluate the thermal sensations (TS) and neutral temperature of the occupants in naturally ventilated (NV) and air-conditioned (AC) classrooms of two technical institutions located in the same premises in the suburbs of Madurai. The main focus of this study is to understand the occupants’ behaviour in response to the thermal conditions of the educational buildings particularly in the warm and humid climatic zone of Madurai.

This research collected data through field studies. The data included 383 survey questionnaires from NV classrooms and 285 from AC classrooms, as well as on-site measurements of interior and exterior weather conditions. The TS results show that the students preferred well-designed NV classrooms than AC classrooms. A new adaptive comfort equation derived from this study can be applied to NV classrooms in warm and humid climates where mean outdoor temperature exceeds 40°C.

The neutral temperature derived for NV classrooms in Madurai ranged from 29°C to 34°C. Thus, the occupants in the NV classrooms of the higher learning educational institutions in the warm and humid climatic region of Madurai can adapt well to higher indoor temperature levels than predicted by ASHRAE comfort levels with minimum adjustments.

The study was limited to only occupants in two premier higher learning technical educational institutions located in Madurai region within 5–10 km within the city limits to understand the implications of microclimate with respect to the urban context. Thus, further research is required to examine the tendency under local conditions in other regions beyond those applied to this study.

The findings of this study showed that occupants in higher learning educational intuitions in Madurai prefer NV classrooms than AC classrooms. Therefore, with rising demands of energy use for mechanical ventilation and the associated high cost for running AC buildings, architects should prioritize the design of energy efficient buildings through the optimal use of passive design strategies for ventilation and thermal comfort. This study gives a base data for architects to understand the adaptive limitations of occupants and design NV buildings that can promote natural ventilation and provide better thermal environments that can help increase the productivity of students.

This paper was an attempt to develop the adaptive comfort model for NV classrooms in Madurai regions. There has been no attempt to identify the adaptive comfort levels of occupants in higher learning technical educational institutions located in warm and humid climatic region of India.

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.

This paper sets out to highlight several aspects of a project, aimed at developing an advanced thermal comfort guideline, based on the adaptive thermal comfort theory.

The paper introduces the new Dutch adaptive guideline for thermal comfort. The initial method exceeding hours (TO) is discussed, as well as the more recent method of weighted temperature exceeding hours (GTO). An evaluation of the practical and theoretical shortcomings of the TO and GTO methods is discussed, as well as the rationale behind the adaptive ATG guideline. Furthermore, the results are presented of computer simulations in which the predictions of the different methods are compared. Productivity effects of the new guideline are also discussed, as well as the implications for cooling system sizing and energy efficiency.

The adaptive temperature limits (ATG) guidelines appears to be a more reliable method for the assessment of thermal comfort, in particular for passive, free‐running buildings, compared with the PMV‐based method of weighted temperature exceeding hours (GTO). Furthermore, the ATG method allows for a wider temperature range for Alpha type buildings and gives more opportunity for the development of sustainable, naturally ventilated buildings and limiting cooling energy.

Although the new ATG method shows promising results, more research is needed. The exact distinction between Alpha and Beta is still subject to further research, as well as the question whether a certain amount of exceeding hours of the ATG limits should be accepted.

The ATG method is being used in The Netherlands for the assessment of thermal comfort in the design stage as well as in the assessment of the performance of buildings in use.

This paper discusses the first application of the adaptive thermal comfort theory in a practical guideline.

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 temperature 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 overheating 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 comfort 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 temperature 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 measures to alleviate overheating risks.

In vernacular buildings, many climatic and passive solutions have been used to create indoor thermal comfort. Seasonal occupant movement is an example of a traditional response to increasing thermal comfort. This article investigates the influence of these user behaviours on thermal comfort in courtyard houses.

Parametric models of three different scenarios of courtyard houses are simulated. The courtyard houses are located in Shiraz, Iran, and share the same orientation and construction materials. To enhance the accuracy of the study, the indoor adaptive thermal comfort (ATC) analysis is performed with three different window-to-wall ratios (WWR) of 25, 50 and 75%. The ACT analysis is performed on an hourly basis for summer and winter scenarios.

The results demonstrate that the indoor ATC is 8.3% higher in winter than in the summer in the seasonal zones. During the summer, the amount of ATC is relatively sustained in all zones. Unlike common beliefs, seasonal movement can enhance the ATC, especially during winter, specifically in the northern part of the courtyard. In northern zones, the seasonal movement of occupants improves the indoor ATC from 10.1 to 23.7%, and in southern zones, the improvement is from 2.2 to 4.8%.

This research presents a new numerical investigation into occupants' seasonal movements in courtyard houses during summer and winter. It provides a precise pattern to show how much this seasonal movement can affect the habitant's ATC.

The purpose of this paper is to explore the role of locally-produced architectural design solutions for the provision of thermal comfort in the vernacular settlements of Mardin, Turkey.

With an aim of extracting clues of climate responsive design, the paper develops a socio-technical assessment methodology and presents a comparative inquiry between the vernacular and contemporary built environments of Mardin.

Findings display that the capacity of vernacular architecture in providing a more climate responsive living environment than contemporary one is in fact correlated with the design of living spaces in harmony with the local climatic conditions as well as how inhabitants traditionally use and behave in designed space.

The paper argues for a need for (re)conceptualization of thermal comfort within and through the production of housing, as well as by taking into account the ways in which end-users interact, adapt and sustain end-users' everyday life in accordance with the local climatic characteristics.

A major challenge faced by West Africa is to find comfortable housing as a result of climate change and population growth. The climatic adaptation of buildings and their indoor environment become an essential condition for maintaining the health and productivity of the occupants. This paper proposes a model to assess the thermal comfort of naturally ventilated buildings in hot and dry climates in Burkina Faso.

The proposed method is an adaptive model which relies on a combination of parameters such as the operative temperature, the new effective temperature and the basic parameters of thermal comfort. It consists in proposing the zones of thermal comfort on the diagram of the humid air for each climatic region.

A decision-making tool is set up for evaluating the comfort of buildings to better consider the bio-climatic concept through a long-term comfort index. This comfort index is defined and is used to assess the degree of thermal discomfort for various types of housing. Two natural ventilation pilot buildings located in Ouagadougou were considered. The results show that the pilot building whose wall are is made of Earth blocks achieves 26.4% of thermal comfort while the building made of hollow cement block achieves 25.8% of thermal comfort.

The decision-making tool proposed in the present study allow building stakeholders to better and easily design, assess and improve the thermal environment of buildings.

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.

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.

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

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