External shading devices have been utilized very extensively in the buildings of tropics to control the amount of daylight and direct sun light flowing into interior spaces. It is now widely accepted that architects should encompass the environmental task of reducing fossil fuel energy consumption in response to climate change. Day light is a blessing of nature. Effective daylight reduces the need of artificial light at day time and thus reduces the overhead cost of energy. Proper luminous environment confirms sufficient daylight which is very good for both physical and mental health. But too much or unguided daylight cause glare and light pollution. For the purpose of examiningthe day lighting design in a residential building in the tropics likeBangladesh, this paper discussesthe effects of different types of fixed external shading devices on daylight flow intobuildings. The investigation was carried out by the use of ECOTECT for day lightingsimulations. A building having south facing openings has been fundamentally chosen as case study. The luminous level of different points in the study room has been collected as field survey. After studying the existing day light condition, daylight simulations have been conducted using several types of shading devices based on the study area. More importance has been given on useful daylight illumination for visual tasks to study the effects of different types of shading devices.

Shading Device, Luminous Level, Daylight Illumination, Simulation, Dhaka