IDOM's high performance office building lighting audit: a case study

Sammanfattning: People in industrialized countries spend most of their time indoors. In this respect, a pleasant indoor environment is therefore very important, and daylight plays a fundamental role in this matter. A good lighting design in offices has proved to improve the worker’s wellbeing and increase their productivity. It has become an important part of the early stages of the building design. Simultaneously, lighting audit methodologies and techniques have evolved in the past few years. This master’s thesis presents a study of daylighting and lighting conditions at the IDOM headquarters located in Madrid, Spain. Several tools such as field measurements with a luxmeter and colorimeter, a questionnaire and daylight simulations with Honeybee were performed. A step-by-step documentation was developed to create a workflow that could be used for future lighting evaluations. Overall, the audit shows that most workers were satisfied with the lighting conditions in the office. User on level one reported similar scores to those on level four. In contrast, users close to the core were less satisfied with the lighting conditions, the uniformity of light distribution and views while users with workspaces close to the window experienced over lighting due to the high daylight illumination. Other correlations linked the uniformity and light satisfaction, and glare from fixtures with low uniformity, which might be an indicator of too directional electrical light sources and a low-lit background. Daylight simulations were conducted for three representative spaces on the fourth floor (open office, cell office and meeting room). The results of these simulations and the subjective assessment indicate similar outcomes. It was also observed that shading devices affect the annual daylight simulations to a great extent. However, it is difficult to measure the extent of the impact since the shades are controlled by the users. Lastly, the study conducted shows that a good daylight design improves the overall energy performance and reduces the consumption of electric lighting by almost fifty percent when daylight is considered.