Building performance evaluation is the process of systematically comparing the actual performance of buildings, places and systems to explicitly documented criteria for their expected performance. It is based on the post-occupancy evaluation (POE) process model (see Figure 1.4) developed by Preiser, Rabinowitz, and White (1988). A comprehensive review of POEs at various environmental scales can be found elsewhere (Preiser, 1999; Federal Facilities Council, 2001).

ost-occupancy evaluation (POE), viewed as a sub-process of BPE, can be defined as the act of evaluating buildings in a systematic and rigorous manner after they have been built and occupied for some time. The history of POE started with one-off case study evaluations in the late 1960s, and progressed to system-wide and cross-sectional evaluation efforts in the 1970s and 1980s. Early POEs focused on the residential environment and the design of housing for disenfranchised groups, especially as a result of rapid home construction after the Second World War. Many urban renewal projects in North America, and new town construction in Western Europe, created large quantities of housing without thorough knowledge of the needs, expectations, behaviour or lifestyles of the people they were being built for. The kinds of social and architectural problems that subsequently arose led to an interest in systematic assessment of the physical environments in terms of how people were using them (Vischer, 2001). The approach was later seen as a mechanism for collecting useful information for the building industry on the impact of design and construction decisions over the long term. POEs have since targeted hospitals, prisons, and other public buildings, as well as offices and commercial buildings. Several types of evaluations are made during the planning, programming, design, construction, and occupancy phases of building delivery. They are often technical evaluations related to questions about materials, engineering or construction of a facility. Examples of these evaluations include structural tests, reviews of load-bearing elements, soil testing, and mechanical systems performance checks, as well as post-construction evaluation (physical inspection) prior to building occupancy. POE research differs from these and technical evaluations in several ways; it addresses the needs, activities, and goals of the people and organizations using a facility, including maintenance, building operations, and design-related questions. Measures used in POEs include indices related to organizational and occupant performance, worker satisfaction and productivity, as well as the measures of building performance referred to above, e.g. acoustic and lighting levels, adequacy of space, spatial relationships, etc. POE is a useful tool in BPE that has been applied in a variety of situations. In some cases, results are published and widely disseminated; in others, they are uniquely available to the architect, to the client, or to the stakeholder who commissioned the study. The findings from POE studies, while primarily focusing on the experiences of building users, are often relevant to a broad range of building design and management decisions. Many of the building problems identified after occupancy have been found to be systemic: information the engineer did not have about building use; changes that were made after occupancy that the architect did not design for; or facilities staff’s failure to understand how to operate building systems. The BPE framework was developed in order to broaden the basis for POE feedback to include a wider range of stakeholders and decision-makers who influence buildings. This has enabled POEs to be relevant earlier in the design process and applied throughout the building delivery and life cycle. The goal of BPE is to improve the quality of decisions made at every phase of the building life cycle, i.e. from strategic planning to programming, design and construction, all the way to facility management and adaptive reuse. Rather than waiting for the building to be occupied before evaluating building quality, early intervention helps avoid common mistakes caused by insufficient information and inadequate communication among building professionals at different stages. While POE focused primarily on users’ experience of the performance of buildings, the most recent step in the evolution of POE towards building performance evaluation is one that emphasizes a holistic, process-oriented approach toward evaluation. This means that
Introduction and Overview8
not only facilities, but also the forces that shape them (organizational, political, economic, social, etc.) are taken into account. An example of such process-oriented evaluations is the Activation Process Model and Guide for Hospitals of the Veterans Administration (Preiser, 1997). Process-oriented evaluations are the genesis of BPE and its theoretical framework. Many stakeholders, in addition to designers and engineers, participate in the creation and use of buildings, including investors, owners, operators, maintenance staff, and, perhaps most importantly, the end users, i.e. the actual persons who occupy and use the building. The term ‘evaluation’ contains the word ‘value’, therefore occupant evaluations must state explicitly whose values are invoked when judging building performance. An evalu-ation must also state whose values predominate in the context within which a building’s performance is measured. A meaningful evaluation focuses on the values behind the goals and objectives of all stakeholders in the BPE process, in addition to those who carry out the evaluation. Finally, it should be noted that there are differences between the quantitative and qualitative aspects of building performance and their respective performance measures, i.e. data that are collected on-site and from building occupants in order to carry out an evaluation. Many aspects of building performance are in fact quantifiable, such as lighting, acoustics, temperature and humidity, durability of materials, amount and distribution of square footage, and so on. Qualitative aspects of building performance pertain to the ambiance of a space, i.e. the appeal to the sensory modes of touching, hearing, smelling, kinesthetic and visual perception, including colour. The qualitative aspects of building performance, such as aesthetic beauty (i.e. the meaning of buildings and places to people) or visual compatibility with a building’s surroundings, can in fact be the subject of consensus among the public. From a planning standpoint, this is evidenced in the process called design review (see Chapter 5), which has resulted in standards for review and guidelines (Scheer and Preiser, 1994). Research consistently shows that the experts and the public disagree on aesthetics and meaning, and that while expert decisions do not lead public taste, public opinions have been shown to be stable over time (Nasar, 1999).