A Constant-theoretical Sampling and Comparison Approach to Optimise Colour Thinking in the Interior-design Process

The relationship between man-made interior designed spaces and the critical element of colour in these spaces is the concern throughout this study. It is the designer who thinks, re-thinks, decides, then applies the colours onto the interior environment; thus is the key to improve the colour outcomes in interiors. It is important to understand how designers deal with colour. Sensing a gap in applying colour for interior design, four routes of data collection were designed: literature review, case studies, interviews, and observations. While collecting data, the need for good analysis was needed; and thus CTSC (Constant Theoretical Sampling and Comparison) method was designed and applied. CTSC meets GTM in some rules, but differs in some others. CTSC clarifies the data collection routes/methods used in this study and proposes new terms and criteria for design process researchers. Many concepts and themes emerged from analysing each route individually; emerged concepts in CTSC are the results of analysing each study (for example: the refined results of the interviews are called the interviews’ emerged concepts). When linking all the emerged concepts of the four study routes together using the proposed CTSC big linking, the findings of the research were defined, and a justified theory was formed in the area of colour-in-interior design. The case studies analysed three interiors in the UK, whereas the interview study was the major in-depth followed route in this thesis, traveling to seven countries and interviewing twenty-five interior designers. The designed observational study included seven interior design projects. Building contacts with more than thirty designers and design practices facilitated more opportunities for the research to emerge in up-to-date concepts and themes, which allowed to result in theory, and gave the research more chances to design future plans. The insights of this thesis can assist future researchers who are interested in both areas: design process, by proposing data collection and analysis useful CTSC method, and the area of colour in interior design, by proposing the CTSC colour in interior design theory, which included crucial findings such as: colour comes first in design processes, and that designers will always like to keep their colour choices open to inspirations.