Introducing the qualitative performance gap: stories about a sustainable building

ABSTRACT

In the design and operations industries, the performance gap is a common discrepancy found between predicted building energy performance and actual energy performance. The performance gap is considered to have negative impacts for the brand of ‘green’ buildings, designers and operators. A socially based analogue is proposed here: the qualitative performance gap, defined as the perceived gap between what inhabitants expect and their actual experience of the building environment. This concept is explored at a regenerative Living Lab: the Centre for Interactive Research on Sustainability (CIRS) in Vancouver, Canada. ‘Official’ and ‘lived’ stories about the building were interpreted from sources of building information and interviews. Expectations about and forgiveness of building performance were gained from pre- and post-occupancy evaluations and interviews. The solution to the qualitative performance gap is not to eliminate it, but, in line with the concept of interactive adaptivity, to use the gap to generate new stories and new consequences for human wellbeing. The qualitative performance gap is thus conceived as positively generative, of new stories of place and identity. This work recommends crafting an ‘official story’ of social aspirations, and a communication feedback loop amongst designers, operators and building inhabitants, transparently sharing successes and failures.     

Assessing the environmental performance of buildings: trends,lessons and tensions

ABSTRACT

Since the 1970s, intense discussions have occurred within the research and practitioner communities on how to assess and influence the environmental performance of buildings. Many different methods, criteria and tools were developed to raise awareness, enable goal formulation, support design and decision-making processes, and evaluate a building’s environmental performance. This development can be retraced through the example of the works of Raymond J. Cole, who made an important contribution to this scientific debate. The integration of environmental performance into a sustainability assessment, the ongoing development of life cycle assessment (LCA) methods, and clients’, financiers’ and assessors’ different demands for environmental performance assessment, raise additional questions and highlight the conflicting goals. Six topics are examined in relation to current developments: the further development of the classic ‘three pillars’ sustainability model; the suitability of assessment criteria and indicators; the handling of technological progress; the discounting of environmental impacts; the environmental assessment of existing buildings; and the further development of legal requirements. ‘Time’ is a key factor relating to LCA, weighing current versus future emissions, ecological value and recycling potential of existing buildings or ‘options’ for different ways to use the building in future. Recommended actions are provided for key stakeholders.     

Evaluation of environmental design strategies for university buildings

ABSTRACT

This paper examines the performance of environmental strategies in seven recently constructed or refurbished university buildings in the UK. These buildings contain a range of administrative spaces, classrooms, libraries and studios, reflecting their often complex, multi-use, heterogeneous nature. The key features of each environmental strategy are described (including passive, mixed-mode or active systems), in the context of the occupants and spaces they serve and the level of interaction that they afford. Energy performance and occupant thermal comfort (assessed by user surveys) are analysed and compared with studies of other non-domestic buildings, which have typically focused on more predictable single administrative uses (e.g. government offices), and unusually effective operation scenarios (e.g. continuous monitoring by expert building managers). The paper concludes by examining two of the case studies that reflect an increasingly common model of ‘flexible’ environmental design in more detail, identifying key features of the strategies for each building that have had a significant impact on their performance. The design assumptions leading to these features will be explored, and key lessons identified, contributing towards the development of a more robust evidential basis for choosing appropriate environmental strategies for university and other non-domestic buildings in the UK.     

Socio-technical case study method in building performance evaluation

ABSTRACT

Raymond J. Cole’s body of work, spanning sustainable design, system complexity and human agency, has encouraged researchers to reconceptualize the notions of comfort and building performance. However, methods for predicting energy use and assessing environmental performance have remained predominantly within a reductionist approach common to physics and engineering. The recognition that building performance is characterized by interactive adaptivity and co-evolution of the physical with the social has not been matched by the generation of new methods. Although social practice theories that articulate the socio-technical nature of the built environment have been increasingly appropriated to understand occupants’ role in performance, the challenge of studying buildings as complex socio-technical systems remains. This methodological paper discusses the application of the case study method (CSM) to the study of 10 retrofit projects selected from the Retrofit for the Future (RfF) Programme in UK between 2011 and 2012. Guided by Greene’s framework for methodological discourse, the epistemic regime is articulated under four headings: philosophical assumptions, investigative logics, guidelines for practice and contribution to system perspective. The discussion of these domains highlights the fecundity of CSM in providing a more nuanced understanding of the interaction between social and technical systems in performance.     

Housing performance evaluation: challenges for international knowledge exchange

ABSTRACT

Developing effective building performance evaluation and feedback processes is a vital part of global efforts to reduce building energy use and gain insight into the actual performance of buildings and technologies. Although attempts have been made to introduce internationally agreed models for these processes, it is clear that various countries are producing different approaches according to their cultural, institutional and policy differences. Knowledge exchange is potentially a key means of developing a shared understanding of values, meanings and practices in relation to building performance evaluation. This paper identifies cultural and institutional barriers in the European Union for international building performance communities of practice utilizing knowledge exchange, from an experiential ‘real-world’ perspective. The preparation of a 30-month research project to help develop building performance evaluation in Poland and an associated bilateral symposium is closely evaluated through an action research case study in terms of the stakeholders, the national contexts in which they operated and the key challenges they faced. Recommendations are then made in terms of the support needed to develop more responsive research programmes in relation to developing international knowledge exchange, and the capacity-building elements required for these international communities of practice.     

Development and visualization of time-based building energy performance metrics

ABSTRACT

In the face of climate change, and as building codes and standards evolve to promote increased building energy efficiency and reduced carbon footprints, it is also important to ensure that buildings, especially housing, can withstand prolonged power outages during extended periods of both extreme cold and hot weather to provide habitable shelter passively. This paper examines an approach for visualizing the impact of robust passive measures in multi-unit residential buildings by examining the ‘weakest links in the chain’ – the suites most susceptible to underperforming – in three climatic zones: Toronto and Vancouver, Canada; and Adana, Turkey. Two time-based and thermal comfort-related metrics are explored: thermal autonomy, a measure of what fraction of the time a building can deliver comfort without supplemental active systems; and passive survivability (also termed thermal resilience), a measure of the length of time a building remains habitable following the onset of a prolonged power outage during a period of extended extreme weather. A visualization of the results of parametric building energy simulations helps guide the selection of passive architectural parameters at the early stages of design to promote enhanced environmental performance and resilience.     

Unintended consequences: institutional artefacts,closure mechanisms and the performance gap

ABSTRACT

Renewable technologies often feature in policies to improve the energy efficiency of buildings. Designers introduce predicted energy values for specific technologies, but are surprised when the technologies fail to perform as expected. Three building projects are used to explore the effect of construction processes on the energy performance of building-integrated photovoltaic (BIPV) technology. In two cases BIPV failed to deliver expected energy generation, while in the third, dramatic changes in project processes and technical specifications were needed to achieve the specified output. A social construction of technology (SCOT) analysis documents how the energy generation of BIPV disappeared from view at certain points as actors focused on building features. A contribution is made to the theoretical development of SCOT by responding to two issues: privileging of cognitive closure mechanisms and the neglect of institutional analysis. The concept of inflection mechanisms is introduced as a second type of closure mechanism. More specifically, the role of institutional artefacts (e.g. planning requirements and schedules) in the construction process is found to contribute to the performance gap. To reduce the ‘performance gap’, practitioners need to focus on the distribution of design responsibility, sequencing of work and the location of expertise.     

Shifting from net-zero to net-positive energy buildings

Numerous building projects have been presented as having ‘net-zero’ energy performance. Such claims use a variety of different approaches: on- and off-site renewable energy technologies, purchasing green energy credits, etc. Efforts have subsequently been directed at formulating clear definitions of ‘net-zero’ that provide some degree of clarity and theoretical framing. The emerging notion of ‘net-positive energy’ buildings raises new theoretical and practical issues and introduces several new design considerations and possibilities. Net-positive energy is explored though viewing the role of a building for adding value to its context and systems in which it is part. Rather than considering only the generation of more exported energy versus its importation to individual buildings or the grid, the emphasis shifts to the maximization of energy performance in a system-based approach. Net-positive energy approaches open a host of new technical, behavioural, policy, and regulatory issues and opportunities not currently evident with net-zero energy buildings. These challenge the primacy of ‘individual’ buildings as the most effective unit to make significant energy gains and the current prevalent expectation that each and every new building should be required to attain net-zero performance. More generally, it highlights the importance of extending the systems limits of energy analysis.     

Defining the environmental performance of neighbourhoods in high-density cities

ABSTRACT

The regenerative design framework aims to ‘engage a broader range of possibilities by moving beyond the immediate building and site boundaries’. It implies that the environmental performance of buildings requires a revised definition so that it considers not only the building itself, but also its contribution beyond its own boundary, i.e. neighbourhoods. In high-density cities, outdoor spaces are culturally considered as the extension of one’s living spaces. The environmental performance of neighbourhoods is particularly important to the health and wellbeing of urban inhabitants. This paper aims to define the environmental performance of neighbourhoods in high-density urban context based on the experience acquired in previous studies in Hong Kong over the last 15 years. These studies cover a wide range of environmental issues including urban climate, outdoor thermal comfort, and daylighting design in high-density cities. Subsequent development of the assessment tools for environmental performance of neighbourhoods in Hong Kong is also presented. The framework of stakeholder engagement, as an integral part of the neighbourhood assessment tool, is discussed. This paper highlights the distinctive features of the environmental performance of neighbourhoods in high-density urban context and how it influences the professional practices in Hong Kong.     

Applying Social Return on Investment (SROI) to the built environment

The effective measurement and dissemination of the impact of design on building users requires an evaluative shift away from measuring building performance towards measuring the outcomes experienced by people. This agenda shares considerable overlap with the emerging concept of ‘social value’ and it is proposed that social impact valuation methods could fill the post-occupancy quantification gap. A review of the social impact sector identifies Social Return on Investment (SROI) as the most developed method with a robust framework for implementation. SROI generates monetized results, anticipated to enhance transferability compared with typical post-occupancy evaluation summaries and facilitate the dissemination and usefulness of findings within the design and construction industry. An in-depth account is presented of a study that trials the six stage SROI method in three non-clinical healthcare buildings; interviews, focus groups, user surveys and financial valuation techniques are used. The SROI results are summarized and the discussion provides a critical reflection on the application of SROI to the built environment: the technical challenges faced, the modifications made as a result, and the lessons learnt from this process. The conclusion offers practical recommendations for future applications of SROI to the built environment.     

Conceptual approaches to wellbeing in buildings: a scoping review

ABSTRACT

Several industry-led initiatives in various countries demonstrate a new interest in wellbeing and buildings. This paper adopts a scoping review method aiming to establish the most prevalent and insightful definitions and dimensions of wellbeing in buildings applied in the recent published literature. The paper adopts a two-step method for identifying and categorizing the conceptual approaches to wellbeing encountered in the current literature. First, an overview is presented of the term ‘wellbeing’ and its development over time. Second, the broad wellbeing categories identified are further refined and complemented via a deductive approach, drawing the final set of conceptual themes informed by the papers reviewed in this study. Nine themes were identified, two of which deductively emerged from the papers included in this study: environmental satisfaction/comfort and cognitive performance/productivity. The findings emphasize the heterogeneity of conceptual approaches to research concerning ‘wellbeing in buildings’, an ambiguity between wellbeing outcomes or determinants, and the need for greater clarity on the relative contributions of different wellbeing dimensions to overall individual or population wellbeing. Based on these findings, future work could be carried out to provide guidance on how to evaluate claims of evidence-based building design which foster individual or population wellbeing.     

Policy implications for the performance gap of low-carbon building technologies

ABSTRACT

It is widely recognized that the actual impact of low-carbon technologies is often lower than predicted by models alone, a phenomenon which has been coined the ‘performance gap’. Despite this awareness, in many instances estimates of both energy savings and renewable energy generation in domestic buildings continue to rely on engineering models and building energy simulations rather than approaches that are based on measured parameters. Much of the existing literature on the performance gap focuses on energy efficiency and is concerned with the quantification of the scale of the performance gap. This paper adds to this body of evidence by drawing retrospectively on a range of grey literature evaluations of low-carbon technologies (including energy-efficiency measures, renewable heat and renewable electricity) in the UK household sector. The focus is on not only the quantification of the performance gap but also the qualitative factors often overlooked, such as installation issues or installer/user behaviour. Recommended policy changes include the development of evaluation standards, the experimentation with pay-for-performance programmes, ensuring that installation standards for low-carbon technologies are being enforced, and taking reasonable steps to ensuring that end users can use any new technology effectively.     

Inhabiting Time

In recent architecture, design has prioritised an engagement with time through its creation of temporary and highly flexible structures. There has, however, been less focus on how the design of buildings might impact the experience of time of the people who inhabit them. Here the distinguished author and emeritus professor Juhani Pallasmaa , who is renowned for his writings on the phenomenology of architecture, provides a reminder of the importance of what it means to ‘dwell in time’.     

Fast network multi-objective design algorithm combined with an a posteriori procedure for reliability evaluation under various operational scenarios

This paper presents a methodology for the optimal design of water supply networks. It features a multi-objective optimisation (aimed at minimising costs and maximising resilience) and a subsequent ‘retrospective’ evaluation of network reliability under various operational scenarios. The multi-objective optimisation is based on an algorithm specifically developed for the design of real networks which feature a very high number of nodes and pipes. The ‘retrospective’ evaluation of network reliability is assessed considering resilience contrasted with several other indexes adopted to describe the operational performance of the network under critical scenarios such as segment isolation or hydrant activation, and different water demand conditions. In the applications two case studies, made up of a simple benchmark network and a real network respectively, are considered for the multi-objective optimisation; the ‘retrospective’ evaluation of reliability is performed only on the real network. The latter example clearly highlights that the procedure proposed allows reliability and performance to be offset against cost, consenting informed choice of the optimal network configuration.     

Challenging the assumptions for thermal sensation scales

Scales are widely used to assess the personal experience of thermal conditions in built environments. Most commonly, thermal sensation is assessed, mainly to determine whether a particular thermal condition is comfortable for individuals. A seven-point thermal sensation scale has been used extensively, which is suitable for describing a one-dimensional relationship between physical parameters of indoor environments and subjective thermal sensation. However, human thermal comfort is not merely a physiological but also a psychological phenomenon. Thus, it should be investigated how scales for its assessment could benefit from a multidimensional conceptualization. The common assumptions related to the usage of thermal sensation scales are challenged, empirically supported by two analyses. These analyses show that the relationship between temperature and subjective thermal sensation is non-linear and depends on the type of scale used. Moreover, the results signify that most people do not perceive the categories of the thermal sensation scale as equidistant and that the range of sensations regarded as ‘comfortable’ varies largely. Therefore, challenges known from experimental psychology (describing the complex relationships between physical parameters, subjective perceptions and measurement-related issues) need to be addressed by the field of thermal comfort and new approaches developed.     

A socio-technical approach to post-occupancy evaluation: interactive adaptability in domestic retrofit

Understanding the process of domestic retrofit is important for learning and innovation. This is particularly the case for low carbon retrofits such as those undertaken under the UK's Retrofit for the Future (RftF) programme, with its aim to achieve an overall 80% carbon reduction by 2050. Current post-occupancy evaluation (POE) research has both theoretical and methodological limitations with implications for technical and behavioural research in the built environment. Drawing on relevant ideas and concepts from social practice theory and science and technology studies, principally prefiguration (constraints/enablement), black-boxing, heating and cooling practices, this paper demonstrates how the relationship between buildings and people could be reconceptualized as mutually constitutive and co-evolving through a process of ‘interactive adaptation’. The concept of ‘interactive adaptation’ is explored through a novel approach to integrating physical and social data collected from a sample of dwellings selected from the RftF programme. Analysis yields insights into the influences and pathways of interactive adaptation resulting from retrofit technology and practices. The implications of these insights for policy-makers, the research community and practitioners are discussed: end-use energy demand policy needs to be informed by a socio-technical approach.     

Development of an adaptive window-opening algorithm to predict the thermal comfort,energy use and overheating in buildings

This investigation of the window-opening data from extensive field surveys in UK office buildings demonstrates: (1) how people control the indoor environment by opening windows; (2) the cooling potential of opening windows; and (3) the use of an ‘adaptive algorithm’ for predicting window-opening behaviour for thermal simulation in ESP-r. It was found that when the window was open the mean indoor and outdoor temperatures were higher than when closed, but it was shown that nonetheless there was a useful cooling effect from opening a window. The adaptive algorithm for window-opening behaviour was then used in thermal simulation studies for some typical office designs. The thermal simulation results were in general agreement with the findings of the field surveys. The adaptive algorithm is shown to provide insights not available using non adaptive simulation methods and can assist in achieving more comfortable, lower energy buildings while avoiding overheating.     

From long-term homelessness to stable housing: investigating ‘liminality’

Abstract

This paper uses the term ‘liminality’ to refer to the experience of feeling like an outsider when people are transitioning from one housing status (long-term homelessness) to another (housed). Three dimensions of liminality are identified: ‘material’, ‘relational’ and ‘psychological’. The material dimension covers how people feel about their housing and whether they find it difficult to make the transition from homeless to housed. The relational dimension focuses on whether people are able to rebuild relations with family and friends. The psychological dimension includes how people deal with the stigma of homelessness. The paper demonstrates that most people can overcome the material dimension of liminality if they are given appropriate support, but they find it more difficult to overcome the relational and psychological dimensions of liminality. We conclude that moving on from long-term homelessness is not straightforward and we point to the policy implications of these findings.     

Non‐destructive investigation

So‐called ‘dynamic'or ‘counterflow'insulation systems have already been installed in buildings in France and Sweden for which significant improvements over ‘classic’ insulation methods have been reported. Here, the authors describe a French study, including full‐scale laboratory tests, into the actual efficiency of a ‘permeodynamic’ version. A theoretical model has been developed from which to derive thermal efficiency values, and is compared with the test results. The limits of such dynamic systems, and their most feasible applications, are then discussed. The main conclusion is that conventional insulation techniques remain competitive for houses, but permeodynamic systems offer greater possibilities for industrial buildings.     

Indigenous relational understandings of the house-as-home: embodied co-becoming with Jerrinja Country

Abstract

The paper considers what housing studies can learn from Indigenous understandings of the house-as-home. Explored through Indigenous ontologies and epistemologies of the house-as-home, the objective of the paper is to offer nuanced understandings of the social and material work of the house itself in the making and unmaking of home. We draw on an Indigenous/non-Indigenous collaborative research, led by Jerrinja elders. The research design included veranda yarning sessions and Indigenous talking circles. Three dimensions emerged strongly from Jerrinja people’s understandings of the making and unmaking of house-as-home: home as an objective capacity, an aesthetic sensibility, and an affective experience of Country. These dimensions are discussed through a relational framework that combines Panelli’s discussion of ‘Country-as-home’, Prout’s idea of ‘kinship-as-home’ and Bissell’s thinking around materiality in achieving comfort. The paper concludes by reflecting on the importance of including Indigenous knowledge if housing studies as a field is to go beyond a Western cultural politics of the house-as-home.