It is suggested that ceramic roof tiles would

It is suggested that ceramic roof tiles would provide better performance in the nebivolol hcl of heat transmitted into a house. Miller et al. (2007) concluded that the heat, which enters from the ceramic tiles of the roof surface into the ceiling, decreases up to 60% or less than asphalt shingles. As ceramic roof tiles became wet during nighttime and dry during daytime, it would help in minimizing the heat transfer from the roof surface into the attic area. The reduction of heat transfer is due to the ability of the material to bounce back the radiated heat to the atmosphere. Although the Chinese had already practiced the use of ceramic as a roofing material for centuries, this choice is not well understood because of modernization and vast development (Miller et al., 2007). The passive design of a modern terrace house is not very suitable for a hot and humid climate such as that in Malaysia (Davis et al., 1997). For a house with a modern low-income design, the indoor temperature is as high as 31°C; while the outdoor temperature is around 30°C with air speeds as low as 0.1m/s (Tinker et al., 2004). The recorded indoor temperature is higher than the temperature of a human׳s thermal comfort. Although the house has many openings, such as windows and doors, it still cannot achieve thermal comfort because the upper part of the house is not properly designed. Similar research is conducted on the same design for a modern low-cost house in two different locations. Ibrahim et al. (2014a) showed that lack of natural ventilation design increases the indoor temperature. Aziah (1994) concluded that the traditional Malay house design records a lower indoor temperature compared with the modern terrace house design. Furthermore, the traditional Malay house design is the best example of good natural ventilation, since it mostly depends on the natural cooling system through the flow of air via windows, doors, roofs, and others (Lim, 1987). However, the application of the traditional Malay concept house has become unpopular due to the modernization of the house design and the limitation of timber supplied for the building material, such as wood and Nipa palm leaf (Nypa fruticans). Fig. 2 shows the openings in a traditional Malay house that could help ease the movement and remove heat. Nowadays, the Malaysian modern roofing system is designed with less ventilation or unvented attics to save costs for construction, fire resistance, rain protection, and increase in security. The modern concrete house built in Malaysia would experience high temperature rises during daytime and would slowly cool down during nighttime (Abdul Rahman et al., 2009). Wolfert and Hinrichs (1974) showed that the roof sheathing temperature of an unvented attics condition and ceiling temperature might reach up to 71°C and 66°C respectively, while the outdoor temperature is only around 32°C. However, a well-designed ventilated roof can improve the overheated condition at the attics, particularly at a moderate height and a wide area of the building (Ciampi et al., 2005). The most affected element because of poor passive design is the energy demand for the mechanical operation. When the condition of the indoor temperature is higher than the comfort level, a large amount of energy is needed to generate mechanical ventilation to achieve the level of comfort (Tinker et al., 2004). However, the condition could become worse because of poor ventilation and air circulation design. The openings in Malaysian houses are located mostly at the front and back parts of the houses, especially in intermediate terrace house design.
Recommendations to improve the current practice on passive design This study proposed the recommendations to improve the current passive design. It is targeted to reduce or maintain the indoor temperature within the comfort temperature range. The recommendations in this study focused on: