Value for money in building design: Modelling the cost-quality relationships

Value can be defined as quality in relation to cost. The relationship between these two dimensions, in the context of a building's design, has to be properly understood if building owners (clients) are to be confident of achieving value for money in the outcome. This thesis proposes a cost-quality modelling technique that evaluates the cost and quality dimensions of early design options, enabling the relationship between them to be explored. The research has revealed problems associated with current practice in terms of early cost advice and the modelling techniques used for providing that advice. Inadequate consideration of the quality dimension was highlighted as a significant cause, due to its perceived elusiveness and complexity. The findings of the research, however, suggest that quality is amenable to a systematic treatment with respect to its representation and measurement. Results of a survey revealed that quality parameters, which are meaningful and necessary for early design generation and evaluation, are not as diverse as first believed. The results also revealed that quality can be examined and expressed in terms of its key contributing parameters. These findings, amongst others, have provided the basis for the development of a framework for quality benchmarks. A cost-quality modelling technique is proposed, based on the integration of the framework for quality benchmarks, a multi-criteria decision-making technique, and graphical and statistical methods. The proposed modelling technique has been applied to example building projects in order to test its sufficiency. Results show that the technique is able to guide the client and design team towards an improved solution in terms of cost and quality.