Comfort paradigms and practices
Heather Chappells & Elizabeth Shove
January 2004
‘Future Comforts’ is a one-year project funded by the UK Economic and Social Research Council’s Environment and Human Behaviour Programme. The project, which started in April 2003, consists of 3 stages: a selective review of interdisciplinary thermal comfort research; interviews with those involved in the specification and construction of indoor environments in the UK; and a workshop to present the results of our interviews and to identify critical themes for future research. As well as providing an overview of the project and a summary of key findings to date, this paper highlights issues for discussion at the workshop.
Background
Vast quantities of energy are required to heat or cool buildings to provide what are now regarded as acceptable standards of thermal comfort. Paradoxically, likely responses to global warming, such as greater reliance air-conditioning, threaten to increase energy demand and emissions of CO2 and exacerbate rather than mitigate the effects of climate change.
It is in this context that the Future Comforts project examines changing conventions and technologies of indoor environmental management. What implications do today’s heating and cooling regimes have for cultural convergence and global environmental change? By interrogating taken-for-granted assumptions about what comfort is we hope to engender wide-ranging debate about ways of developing indoor environments that do not exacerbate existing problems or contribute to as yet unappreciated risks. As a starting point we consider how meanings and expectations of comfort have changed and with what consequences for the indoor environment.
Meanings of comfort
‘Comfort’ can be understood as a physical condition, a feeling of contentment or a sense of well-being. In acknowledging these different interpretations, we start from the proposition that comfort is a social and technical construction, the meaning of which has changed over time. In the course of the last century, different theories of what constitutes a ‘good’ or ‘comfortable’ thermal environment have fallen in and out of favour. In the early 1900s “fresh air” campaigners in the United States argued that pupils should study outdoors, this being essential for the development of healthy bodies and minds. The designers of today’s air-conditioned offices conclude that productivity and comfort can best be achieved by keeping outdoor elements (including fresh air) at bay. These contrasting ideas give a flavour of the historical malleability of the concept of comfort and of how different interpretations influence strategies of thermal regulation.
Cultural differences are also important. People living in different social and climatic environments have, for instance, reported being comfortable at temperatures ranging from 6 to 31OC. Having acknowledged cultural and historical diversity in meanings and expectations of comfort, we have tried to show how and why different ideas about thermal comfort have evolved and how these frame more and less sustainable design strategies.
Perspectives & paradigms
Questions of thermal comfort have been addressed by building scientists, urban planners, social scientists, historians and anthropologists but to date there has been little attempt to bring these lines of enquiry together or analyse the different perspectives on offer.
One aspect of our work has been to review a selection of relevant literature including: physiological analyses of comfort; studies of thermal perception from the building and engineering sciences; anthropological and historical work on changing concepts of comfort; studies of social and cultural variation in heating and cooling practices; and research into the socio-technical construction of comfort. From this review we have identified different families of ideas about comfort – as shown in Figure (1).
Figure (1) Comfort paradigms
|
THEORY OF COMFORT |
DEFINING COMFORT |
DETERMINING COMFORT |
ACHIEVING COMFORT |
|
|
PHYSIOLOGICAL |
Biological heat balance |
Definable universal condition |
Laboratory experiments |
Provide comfortable conditions efficiently |
|
ADAPTIVE |
Physiological/Behavioural adaptation |
Definable condition |
Field studies |
Provide adaptive opportunities |
|
SOCIAL CONVENTION |
Social/cultural experience |
Matter of cultural/historical convention |
Ethnographic enquiries |
Facilitate diversity |
The first column lists three broad ‘paradigms’ of comfort – physiological, adaptive and social convention. The next two columns record differences in theories and meanings of comfort across these paradigms. The final two columns consider the implications of these ways of thinking for the methods of enquiry through which comfort is assessed, and for how comfortable conditions might be achieved more sustainably. As this summary suggests, proponents of contrasting philosophies and paradigms favour significantly different ways forward.
Physiological approaches take comfort to be a definable condition determined by the relation between external conditions and the responses of the human body. Laboratory experiments involving human subjects have been important in isolating relevant parameters and pinning down conditions (of temperature, humidity, metabolic rate etc.) under which people report being comfortable. Having determined the constituents of comfort in this way, it is then possible to specify optimal conditions with respect to biologically determined thermal requirements.
Proponents of what we term an adaptive approach also take comfort to be a definable condition, however they conclude that people’s expectations of thermal environments, and their ability to react to changing conditions, are important determinants of experience. Field studies have served to expand and extend the range of physiological and behavioural factors believed to influence human comfort. Consistent with this approach, the provision and achievement of comfort is believed to depend on the availability of options for personal adjustment and/or environmental modification.
Those who argue that, within certain biological limits, definitions of comfort are ultimately matters of ‘social convention’ highlight the extent of historical and cultural variability. From this perspective, the meaning and achievement of comfort depends on the social and political context in which it is defined and constructed and in which expectations are reproduced. Such expectations are, in turn, influenced by heating or cooling regimes and by the practices and ways of life associated with them.
How do these paradigms relate to the provision of thermal comfort? To address this question we interviewed a number of people involved in the design, construction and specification of indoor environments in the UK – including architects, services engineers, building regulators, air-conditioning manufacturers, property developers and policy-makers.
Comfort-making in practice
Our interviews with contemporary ‘comfort-makers’ were designed to find out how and why certain ideas about comfort have become embodied in indoor environments and how these frame user practices and patterns of energy use. Our enquiries addressed issues of:
Changing meanings and expectations
The architects and engineers with whom we spoke viewed ‘comfort’ as much more than a physically defined condition, often acknowledging a huge variety of cultural and behavioural interpretations. At the same time, they routinely organised their work around those few aspects of ‘comfort’ that could be quantified and so measured and monitored. In this they were often ‘led’ by clients who translated the generic notion of ‘comfort’ into a precisely specified set of indoor environmental conditions. In noticing an increasing trend in the quantification and monitoring of building performance, several respondents were concerned that clients might reach for yet more exacting specifications, beyond those which could be met with any degree of reliability and beyond the margins of what it was reasonable to expect. As they explained, such developments foster the development of increasingly standardised indoor environments and increasingly ‘demanding’ standards.
For these and other reasons, respondents suggested that user expectations of comfort and indoor environments had changed dramatically over the last few decades. Most notably, people now expect air-conditioning in cars and offices, hotels and shopping malls. Homes were identified as a notable ‘blip’ in this pattern, but the rise of domestic air-conditioning was seen as an inevitable trend. For policy makers and regulators this represented a real dilemma: should they promote the uptake of more energy efficient air-conditioning systems or would this legitimise their use and further exacerbate environmental problems?
Standards and regulations
Our interviews revealed the ambiguous role of standards and regulations in promoting and stabilising particular meanings of comfort. Building regulations (part L) and guidelines such as those produced by CIBSE or the British Council of Offices influence but do not determine the definition and provision of comfort.
In some cases building design was represented as rather prescriptive process. Operating within the confines of current regulations and standards, designers sought to provide whatever type of indoor environment the client desired. As one building engineer explained the goal was to provide a solution that clearly met the clients needs. Given the current commercial and regulatory environment, there were no ‘brownie points’ for environmental innovation, or for initiating debate about what comfort really means.
In other situations, architects and engineers sought to stretch the ‘rules’, working with clients to redefine the margins of acceptability and promote innovative designs above and beyond ‘normal’ standards and specifications.
The scope for innovation was, itself, structured – most obviously by a number of turning points beyond which designers were literally locked into one or another course of action. Critically, the decision to have (or not to have) air-conditioning sets the scene not only for much of the rest of the design, but also for the way in which ‘comfort’ is subsequently conceptualised, measured and monitored. This move also influences users expectations and aspirations. As this example makes clear, such decisions change the criteria and the frame of reference for all that follows and so have a self-fulfilling momentum of their own.
Diversity of interpretation and expectation
Our conversations with comfort-makers showed that contemporary expectations of comfort vary widely depending on the type of environment in question. Different conditions and experiences count as comfortable in schools, hospitals, cars, trains and homes. The importance attached to ventilation and air quality, and the apparent significance of these and other variables is not the same across all building types. For example, people are expected to be, and often are, better able to adapt to changing external conditions when they are at home. Office developers work with different models and concepts of comfort partly because they have to contend with, and design for, a very different (less flexible) social situation. It is, of course, important to acknowledge the relation between the social and the technical. It is partly because people expect office environments to be standardised that they are so and it is partly because of this that design options are limited.
Other social and cultural distinctions were important in terms of users’ expectations and with respect to professional understandings of what counted as a ‘normal’ specification. For example, several respondents explained that air-conditioning is regarded as such an essential part of a ‘normal’ US office that it would now be impossible to do without it – whatever the weather outside. These and other commentators suggested that decisions about indoor environments were strongly shaped by issues of status and symbolism, air-conditioning generally being associated with quality and prestige.
Overall, it is clear is that historically and culturally variable expectations of what different environments should be like inform the sorts of conditions that are produced and reproduced in practice.
Comfort and climate change
Respondents were asked to comment on what they saw to be key issues and trends for the future. They were also asked about how they might revise current practice in response to concerns about global warming and long-term climate change. Although many of those with whom we spoke saw no ‘need’ for domestic air-conditioning they suggested that changing consumer expectations might drive the industry in this direction. Some were of the view that strong regulation – ‘a big stick’ or even a ban on domestic units – would be required if there was to be any chance of halting this trend. Not surprisingly, air-conditioning manufacturers favoured less prescriptive policy, for example suggesting that targets for CO2 reduction might be achieved through any number of routes – including the promotion of energy efficient air-conditioning units or those run on renewable energy. A few of those we interviewed went much further, arguing for a re-evaluation of entire ways of life – for example, advocating the introduction of the siesta on especially hot days.
More pragmatically, standards-making bodies and government regulators were concerned to revise guidelines to better suit the needs of those designing (or wanting to design) naturally ventilated buildings. As one engineer explained, this was not a case of ‘throwing Fanger out of the window’, but of modifying methods of calculation to reflect changing expectations and concerns over climate change. The widespread adoption of more ‘adaptive’ standards was, however, thought to depend upon the thermal comfort research community’s ability to develop methods capable of delivering consistent and reliable results. This was seen as critical if clients were to be convinced that passively cooled buildings could deliver comfort. The irony is that although recognising the need to set standards that permit (if not encourage) the use of natural ventilation, the standard setting process continues to ‘demand’ levels of precision of a kind associated with and perhaps only deliverable through mechanical control. Meanwhile, regulators and policy-makers remain concerned that efforts to incorporate environmental design criteria will be overtaken by events, swamped by changing and increasingly demanding consumer expectations.
Future Comforts: implications and issues
Our interviews show that there is persistent diversity in how design professionals, clients and users measure, define and interpret comfort. This variation occurs within a loosely defined ‘envelope’ of normality – as we have shown, what counts as normal in the UK today is not ‘normal’ either in the USA now, nor would it have been ‘normal’ in the UK even a decade or two ago.
It is nonetheless important to appreciate that different ‘actors’ within the design system have greater and lesser degrees of flexibility in how they specify and achieve comfort, and in what impact their ‘definitions’ have on others.
In relation to the typology developed above, there is a good deal of slippage between comfort paradigms. In practice, comfort-makers continually adjust strategies and expectations so as to ‘fit’ the conventions associated with particular environments, types of clients or users.
This leads us to conclude that ‘comfortable’ indoor environments are a product of the specific context in which they defined, evaluated and achieved. Much therefore depends upon the range of actors involved, their relative influence one with respect to another, and the comfort-related paradigms (and associated vocabularies and methods of measurement) on which they draw. The design process is also important. As mentioned above, early decisions foreclose subsequent options, thereby locking people and buildings into certain comfort regimes or trajectories – a feature that is particularly important given the longevity of the built environment. In summary, our findings suggest that the future of the indoor environment depends on different actors’ success (and failure) in promoting and stabilising specific meanings and expectations of comfort.
Building on this work, the Future Comforts workshop provides an opportunity to reflect on the following questions: