An increase in the design of buildings with glass and metal to achieve architectural aesthetics and outdoor views is beginning to receive more attention, claimed by some as a second revolution in glass architecture. The benefits of daylight through the transparent envelopes are unquestionable. When sunlight is introduced into a space, its role in general illumination is what is of interest in this study. Results show that sunlight received in the interior of a building after refurbishment can serve a useful purpose as an additional source of natural illumination. (C) 2003 Elsevier B.V. All rights reserved.