Abstract:
Research has shown that colour stimuli could trigger certain fixed emotional and behavioural responses within human beings. Consequently, transcending its typical aesthetic value, colours have a greater potential to be integrated into design in a way that can stimulate required emotions and behaviour in the built environment to enable optimum human performance. This attribute is identified in the present study as an important aspect of the ‘functional value of colour’. Literature on theory of colour explains the relationship between colour and human’s thermal perception (TP), distinguishing warm colours (red, orange, yellow), cools colours (blue, green, purple) and neutral colours (white, grey, black). This study emphasises that every human activity demands a unique thermal condition or environment for its optimum performance. In consequence, it was hypothesised that colours could be potentially used to manipulate human thermal environment as demanded by the activity intended in any built space. Hitherto, the scientific investigations done on the nature and potential of this association are scarce. The present research attempts to provide evidence for TP related to a few selected colours, while identifying certain associated functions for aforementioned colours. A group of normal sighted, healthy volunteer undergraduates (n=72) of the same age (20-23) were shown computer generated slides of a typical room in seven different colours as specified in RGB colour model, projected on to a wall ; red( 255,0,0), orange (255,165,0), yellow (255,255,0), blue (0,0,255), green ( 0,128,0), purple (128,0,128), white (255,255,255) within a controlled studio environment. While maintaining a constant ambient temperature (26oC), the participants were exposed to each slide for two minutes. They rated their thermal perception (warmness/coolness) of each room on a 5-point likert scale and selected activities they would prefer to perform, in each room out of a list of activities provided to them, imagining that they were actually experiencing each coloured room shown in the slides. Findings of this study provide testimony for colours’ ability to alter human’s thermal perception. Explicitly, TP of red, orange and yellow colour slides were rated as warm and blue, green, purple slides were rated as cool while white slide was found to have an average TP. Red was found to trigger the highest TP and blue, the lowest TP. The following relationship between TP of the seven colours tested was arrived at; TP Red > TP Orange > TP Yellow > TP White > TP Purple > TP Green > TP Blue. Supporting the hypotheses, the participants preferred to perform active functions in the rooms which they rated to have a high TP and vice versa. For instance, red room was preferred for exercising and sports, while orange was selected for sports, dining and exercising. Yellow was imagined as suitable to support discussions, dining and sports. The colours identified to have a low TP were significantly preferred for calm activities. Blue and purple respectively were decidedly preferred for sleeping and secondly for relaxing. Green room was dominantly preferred for relaxing. White which was rated to have an average TP was chosen for calm and neutral activities, mainly drawing, reading and meditation.