A Field Study of Thermal and Visual Performance of Self-Shading Energy Commission Diamond Building, Putrajaya, Malaysia

Objectives: This study investigates daylighting condition and cooling effects of a self-shading Energy Commission Diamond building in Putrajaya, Malaysia, using field measurements. Methods/Statistical Analysis: The field data were collected using a HD35ED series data logger measuring instrument with a HD35AP base unit. Findings: The results from the field measurement indicate that illuminance in the building resulting from daylighting alone are above 200 Lux. The average daylight factor is 2.7% which is within the acceptable range of indoor illuminance. From the calculations of OTTV, it is clearly shown that there is reductions of heat transfer into the Diamond building due to it incline wall facade that provide self-shading on the building. The average amount of sensible heat energy within the building is 45.8 KJ/Kg, with the west wing and the south wing indoor office spaces having a difference of about 1.5 KJ/Kg in their enthalpy. On an average, there is a total reduction of 30.6 KJ per unit volume of heat gain into the Diamond building based on the enthalpy change. Considering occupants comfort and wellbeing in the building, the daylighting requirements and heat gain in the building are acceptable. Applications/Improvement: This result is an indication that self-shading in buildings provides efficient daylighting and cooling which in turn reduces the building energy consumption.