This section briefly discusses the general process of evaluation in theory. The most widely used evaluation method is a traditional “pre then post” test, where participants are asked a series of questions both at the beginning (pre-test) and then again at the programme’s completion (post-test). This evaluation method measures changes in the development of a demountable building design. Normally, terms such as pre-occupancy evaluation and post-occupancy evaluation are used by
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researchers or consultants when they are evaluating residential building projects. Both pre-occupancy and post-occupancy evaluation can be conducted through questionnaires, in-depth semi-structured or face-to face interviews, and computer software techniques to examine users’ perspectives on building performances in terms of function and energy cost consumption. The focus here is on post-occupancy evaluation because the functional performance of a demountable building is best revealed during this process after it opens to the public.
Pre-Occupancy Evaluation
Pre-occupancy evaluation can be understood as an assessment process carried out at the early stages of the design of demountable buildings. At this stage, designers often use software and models to estimate the project costs and construction time. Many projects can be delayed for various reasons, such as costs, the availability of materials, construction machinery or the weather. In some circumstances, conducting a pre-occupancy evaluation is essential for the clients to obtain permission for construction on site. For example, one of the research case studies, the Kreod project, was evaluated by the designer before the construction started on site in order to obtain permission from Greenwich Council. In its Design and Access Statement, the designer introduces and analyses the project from eleven perspectives: site location, social context, planning policy context, design, use, scale, layout, landscaping, appearance, access statement (accessibility, implementation, building approach and access, public circulation) and public toilets. Specifically, it claims that “no trees are to be felled in order to facilitate the proposed development”.15 Special consideration was given towards the accessibility of the structure:
It is the intent of the design for the Kreod to facilitate an inclusive, accessible environment for all users of the pavilion. Where appropriate we have designed the scheme in accordance with Part M of the Approved Documents of the Building Regulations and BS 8300: 2009. This will not only provide an environment that addresses the needs of those with disabilities but also provide benefits to others (e.g. older people, families with small children) by the improved accessibility. Disabled users will not be treated in any manner less favourably than those who are able bodied for a reason due to their disability.16
15 Chunqing Li, "Design & Access Statement,"
http://onlineplanning.greenwich.gov.uk/acolnet/documents/51488_4.pdf (assessed 11 November 2011).
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Pre-occupancy evaluation is also important in aiding the management of project schedules and to ensure deadlines can be met.
Monitoring
Once a decision is made to build, monitoring is essential. The Guidelines for the Evaluation of Post Disaster Programmes state that monitoring can be understood as a continuous process throughout the project cycle that assists managers in assessing early signs of positive impacts or potential problems in the project. Evaluation, although it is closely linked with monitoring, is more structured, and is carried out at specific intervals during the project cycle. Monitoring is usually based on judgement, whereas evaluation is more selective and determines specific criteria such as relevance, success and performance of the project.17
As such, monitoring is the systematic and continuous collecting and analysing of information about the progress of a project or programme over time. It is useful for identifying strengths and weaknesses in a project or programme and for providing those responsible for the work with sufficient information to make correct and timely decisions to improve quality. Information about the work, the impact it is having and the external environment needs to be collected and analysed on a continued basis. The results can then be fed directly back into the planning process and any necessary changes can be made. Monitoring ensures that the work stays on course, by checking that activities are implemented, measuring progress towards objectives, identifying problems as they come up, identifying strengths and adapting to changing circumstances. Monitoring is the key to good planning, and the more effective the process, the easier it is to carry out the subsequent post-occupancy evaluation.
Post-Occupancy Evaluation
Preiser et al. define post-occupancy evaluation (POE) as:
The process of evaluating buildings in a systematic and rigorous manner after they have been built and occupied for some time. POEs focus on building occupants and their needs, and thus they provide insights into the consequences of past design decisions and the
17 The United Nations Centre for Human Settlements (UNCHS) Habitat and Unit, Guidelines for the
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resulting building performance. This knowledge forms a sound basis for creating better buildings in the future.18
POE can determine whether a project has achieved the original design intentions and expectations, and assesses the comprehensive effects after the project is put into operation. In addition, POE enables decision-makers to grasp the effects of project investment to improve the investment objectives and evaluation system. POE methods can help analyse human responses to existing buildings, and these methods assess the behaviour of people in settings such as schools, offices and exhibitions. Its purpose is to find correlations between a building and the behaviour of its inhabitants for the purpose of improving current situations or for developing knowledge that can guide the design of similar facilities.
One of the better known of such studies is William Whyte’s video documentary of small urban places in New York City (1980), which led to the formulation of municipal design ordinances intended to improve the urban landscape. The 55- minute film is the result of a three-year research programme entitled The Street Life Project. The research group studied a cross-section of spaces, which included sixteen plazas, three small parks and a number of small spaces. The team used cameras and clocks marked the points in time to enable evaluation of the film.19 Whyte states that evaluation is the critical point in the whole filming process, and that the essential thing to do is to “interrogate the film”,20 which means asking questions when running through it. Whyte suggests that running the film back and forth at a fast speed is a creative method of evaluation, because previously unnoticed things can be identified in this way.21
Shiem-Shin Then argues that POE can be used to deal broadly with the relationship between a building and its users from social and cultural perspective.22 He also shows that POE has been accepted and supported by “tools and techniques that attempt to bridge the divide between the design, construction and building-in-use phases of the building life cycle, both in terms of communication during project brief
18 Wolfgang F. E. Preiser, Harvey Z. Rabinowitz, and Edward T. White, Post-occupancy Evaluation
(New York: Van Nostrand Reinhold, 1988), 3.
19 William Hollingsworth Whyte, The Social Life of Small Urban Spaces (Washington, D.C.:
Conservation Foundation, 1980), 16.
20 Ibid., 109. 21 Ibid.
22 Danny Shiem-Shin Then "Post-occupancy Evaluation" In John Kelly et al., Best Value in
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formulation and construction period, as well as feedback from the occupiers of the building in use”.23
There are few existing evaluation methods that directly address the functional performance of demountable buildings during the design process itself. This is because relatively little is understood about how people react socially, psychologically and cognitively to their physical environment. Analysing human responses is complicated by the influence of cultural factors, which are themselves the result of education, social habits and beliefs. People of different cultural backgrounds may have varying opinions about the same building, and, therefore, it can be argued that evaluating the impact of buildings based on visitors’ responses is one of the most difficult aspects of functional performance evaluation. As Kalay concludes: “it requires an understanding of human perceptive and cognitive processes and the ability to interpret and evaluate them within complex socio- demographic and cultural contexts”.24