Today, the building sector is one of the greatest energy consumers of the world. Therefore, it is important that designers think about strategies to save energy at the different stages of the building process, including during its life. Considering that a great deal of energy will be spent in artificial lighting, an improvement in the performance in front of light of the architecture itself could lead to a better vision of the spaces, which depends on the quantity and quality of light available and on the architectural characteristics as well. One of the most influential aspects is the colour of the space. Here, a case study is presented in which three coloured spaces were assessed by observers under different lighting conditions. Luminance and illuminance measurements were taken to compare these values with the votes given. The results query the correlation between measured values and luminosity of three-dimensional spaces. As a consequence, the choice of a particular colour may increase the sensation of light in a space and, therefore, a reduction of energy use in artificial lighting is possible. In addition, architectural design can take advantage of colour to improve the visual quality of indoor spaces. (C) 2014 Elsevier B.V. All rights reserved.