Daylight performance of courtyard wall design at low-cost flat in the tropics

Courtyard in a low-cost flat in the tropics provides daylight but it is usually protected with a corridor to control the solar radiation. Surrounded by a shaded corridor, daylight level of the adjacent dwelling rooms around the courtyard are reduced. Modification of courtyard wall by integrating a sloped light shelf is proposed to improve the daylight level on dwelling room and control excessive light penetration at the corridor. Experiment with simulation as a tool was used as a research method. Illuminance value, Daylight Factor and uniformity ratio of the base case, a courtyard wall design in a typical low-cost flat in Surabaya (latitude 7�15�55��S) using louver and case, a proposed courtyard wall design using sloped light shelf were compared, simultaneously with daylighting standards. The results demonstrated that courtyard wall modification reduced excessive average illuminance on the corridor in the range of 41% to 57.1% and improved average illuminance in dwelling room in the range of 0.9% to 19.2%. The proposed courtyard wall also increased illuminance uniformity ratio in both corridor and dwelling room. In order to improve daylight quantity and quality, a courtyard wall with sloped light shelf can be applied on a low-cost flat in the tropics