Thermal Performance of Bared and Recessed Façade Window Shading Typology in a Hot and Humid Climate

Occupants' thermal discomfort in buildings of hot and humid climatic region cannot be overemphasized due to the challenge posed by global warming and climate change. Architects are identified as stakeholders that can greatly contribute to the mitigation of thermal discomfort through building design. Therefore, two facades typology i.e., recessed facade window shading and bared facade typology were measured and confirmed that each has different thermal performances as they possess various shading capabilities. This paper examined the capability of the two typologies with different settings with the view to determining their ability of shading buildings against the effect of solar insolation. The method adopted in this study, is an experimental field measurement using U-series Data-loggers to record the radiant temperature, relative humidity, indoor air temperature and ambient temperature of both buildings within the office occupancy period; between 7: 00 am to 7: 00 pm of 11th to 13th January 2016 being the coolest period in Malaysia weather. The data was analysed through statistical tool to deduce various interpretations. The results showed that the rate of solar transmission into the interior of bared facade is 84.2%, representing 331.58 W, the recessed facade recorded only 12.8% representing 48.72 W. Furthermore, recessed facade reduced indoor air temperature by 5 degrees C, while bared facade reduction is less by 1.9 degrees C compared to ambient temperature. The temperature reduction difference revealed the advantage of heat reduction by recessed facade over the bared facade typology. The authors recommendation that further research focus on measuring the two typologies within the same building, orientation and window wall ratio (WWR) not considered in this research.