Evaluating assumptions of scales for subjective assessment of thermal environments – Do laypersons perceive them the way, we researchers believe?

People's subjective response to any thermal environment is commonly investigated by using rating scales describing the degree of thermal sensation, comfort, and acceptability. Subsequent analyses of results collected in this way rely on the assumption that specific distances between verbal anchors placed on the scale exist and that relationships between verbal anchors from different dimensions that are assessed (e.g. thermal sensation and comfort) do not change. Another inherent assumption is that such scales are independent of the context in which they are used (climate zone, season, etc.). Despite their use worldwide, there is indication that contextual differences influence the way the scales are perceived and therefore question the reliability of the scales’ interpretation. To address this issue, a large international collaborative questionnaire study was conducted in 26 countries, using 21 different languages, which led to a dataset of 8225 questionnaires. Results, analysed by means of robust statistical techniques, revealed that only a subset of the responses are in accordance with the mentioned assumptions. Significant differences appeared between groups of participants in their perception of the scales, both in relation to distances of the anchors and relationships between scales. It was also found that respondents’ interpretations of scales changed with contextual factors, such as climate, season, and language. These findings highlight the need to carefully consider context-dependent factors in interpreting and reporting results from thermal comfort studies or post-occupancy evaluations, as well as to revisit the use of rating scales and the analysis methods used in thermal comfort studies to improve their reliability

The Scales Project, a cross-national dataset on the interpretation of thermal perception scales

Thermal discomfort is one of the main triggers for occupants' interactions with components of the built environment such as adjustments of thermostats and/or opening windows and strongly related to the energy use in buildings. Understanding causes for thermal (dis-)comfort is crucial for design and operation of any type of building. The assessment of human thermal perception through rating scales, for example in post-occupancy studies, has been applied for several decades; however, long-existing assumptions related to these rating scales had been questioned by several researchers. The aim of this study was to gain deeper knowledge on contextual influences on the interpretation of thermal perception scales and their verbal anchors by survey participants. A questionnaire was designed and consequently applied in 21 language versions. These surveys were conducted in 57 cities in 30 countries resulting in a dataset containing responses from 8225 participants. The database offers potential for further analysis in the areas of building design and operation, psycho-physical relationships between human perception and the built environment, and linguistic analyses

The Scales Project, a cross-national dataset on the interpretation of thermal perception scales

Thermal discomfort is one of the main triggers for occupants’ interactions with components of the built environment such as adjustments of thermostats and/or opening windows and strongly related to the energy use in buildings. Understanding causes for thermal (dis-)comfort is crucial for design and operation of any type of building. The assessment of human thermal perception through rating scales, for example in post-occupancy studies, has been applied for several decades; however, long-existing assumptions related to these rating scales had been questioned by several researchers. The aim of this study was to gain deeper knowledge on contextual influences on the interpretation of thermal perception scales and their verbal anchors by survey participants. A questionnaire was designed and consequently applied in 21 language versions. These surveys were conducted in 57 cities in 30 countries resulting in a dataset containing responses from 8225 participants. The database offers potential for further analysis in the areas of building design and operation, psycho-physical relationships between human perception and the built environment, and linguistic analyses

Evaluation of Indoor Thermal Comfort Conditions of Residential Traditional and Modern Buildings in a Warm-Humid Climate

Achieving optimal levels of indoor thermal comfort in a warm, humid climate continues to pose a challenge to building occupants in such climatic regions. Buildings are either being retrofitted or designed differently to cater to thermal comfort. As a result, a variety of tactics have been deployed to guarantee optimal thermal comfort for occupants. Some scholars have highlighted the salient contributions of various types of construction materials toward the delivery of different housing types which perform differently under a diverse range of climatic conditions. A plethora of studies suggesting better indoor thermal comfort performance of traditional buildings as compared to contemporary dwellings due to various reasons have been observed. However, limited studies have sought to investigate this suggestion within warm, humid climatic regions. As such, this study engages in an evaluation of indoor thermal comfort qualities of traditional and modern buildings during the dry season with the goal of developing design guidelines for a thermally pleasant environment in a town, Okigwe, which is situated in a warm, humid climatic region in Southeastern Nigeria. Data were collected utilizing a field measurement technique. Throughout the survey period, variables of the indoor environment such as relative humidity and air temperature were recorded concurrently in nine selected buildings, two traditional and seven modern buildings. The fluctuations and differences in relative humidity and air temperature between the two building types were investigated using Z-test statistical techniques. The study’s results revealed that the contemporary structures’ indoor air temperature (29.4 °C) was 0.6 °C higher than traditional buildings’ indoor air temperature (28.8 °C). Therefore, the study recommends that architects and planners should make concerted efforts to integrate methods of passive design into the provision of a comfortable indoor thermal environment rather than relying solely on active design strategies, which whilst lacking in traditional buildings, nonetheless did not prevent such buildings from recording lower air temperature readings compared to modern buildings

Evaluation of Indoor Thermal Comfort Conditions of Residential Traditional and Modern Buildings in a Warm-Humid Climate

Achieving optimal levels of indoor thermal comfort in a warm, humid climate continues to pose a challenge to building occupants in such climatic regions. Buildings are either being retrofitted or designed differently to cater to thermal comfort. As a result, a variety of tactics have been deployed to guarantee optimal thermal comfort for occupants. Some scholars have highlighted the salient contributions of various types of construction materials toward the delivery of different housing types which perform differently under a diverse range of climatic conditions. A plethora of studies suggesting better indoor thermal comfort performance of traditional buildings as compared to contemporary dwellings due to various reasons have been observed. However, limited studies have sought to investigate this suggestion within warm, humid climatic regions. As such, this study engages in an evaluation of indoor thermal comfort qualities of traditional and modern buildings during the dry season with the goal of developing design guidelines for a thermally pleasant environment in a town, Okigwe, which is situated in a warm, humid climatic region in Southeastern Nigeria. Data were collected utilizing a field measurement technique. Throughout the survey period, variables of the indoor environment such as relative humidity and air temperature were recorded concurrently in nine selected buildings, two traditional and seven modern buildings. The fluctuations and differences in relative humidity and air temperature between the two building types were investigated using Z-test statistical techniques. The study’s results revealed that the contemporary structures’ indoor air temperature (29.4 °C) was 0.6 °C higher than traditional buildings’ indoor air temperature (28.8 °C). Therefore, the study recommends that architects and planners should make concerted efforts to integrate methods of passive design into the provision of a comfortable indoor thermal environment rather than relying solely on active design strategies, which whilst lacking in traditional buildings, nonetheless did not prevent such buildings from recording lower air temperature readings compared to modern buildings

Evaluating assumptions of scales for subjective assessment of thermal environments – Do laypersons perceive them the way, we researchers believe?

People's subjective response to any thermal environment is commonly investigated by using rating scales describing the degree of thermal sensation, comfort, and acceptability. Subsequent analyses of results collected in this way rely on the assumption that specific distances between verbal anchors placed on the scale exist and that relationships between verbal anchors from different dimensions that are assessed (e.g. thermal sensation and comfort) do not change. Another inherent assumption is that such scales are independent of the context in which they are used (climate zone, season, etc.). Despite their use worldwide, there is indication that contextual differences influence the way the scales are perceived and therefore question the reliability of the scales’ interpretation. To address this issue, a large international collaborative questionnaire study was conducted in 26 countries, using 21 different languages, which led to a dataset of 8225 questionnaires. Results, analysed by means of robust statistical techniques, revealed that only a subset of the responses are in accordance with the mentioned assumptions. Significant differences appeared between groups of participants in their perception of the scales, both in relation to distances of the anchors and relationships between scales. It was also found that respondents’ interpretations of scales changed with contextual factors, such as climate, season, and language. These findings highlight the need to carefully consider context-dependent factors in interpreting and reporting results from thermal comfort studies or post-occupancy evaluations, as well as to revisit the use of rating scales and the analysis methods used in thermal comfort studies to improve their reliability