Ventilation Potential: Examining the Effects of Growing Densification in the Tropics

The density of Dhaka is increasing exponentially, and with it the demand for residential accommodation. Rapid densification is increasing hard surfaces and changing the urban texture, thereby escalating heat absorption. This intensifies dependency on valuable conventional energy resources, for thermal comfort. Research shows that regional climatic data differs markedly from localised microclimatic effects within the built environment. In built-up residential areas of the city there is the lack of natural wind flow, one of the most important ingredients for comfort during the warm monsoons. Electricity is growing costlier day by day and its supply is erratic, while load shedding to balance the supply and demand, is very common. This paper presents the findings of an ongoing research, to investigate the effects of growing densification in the city on the potential for natural ventilation. The work is based on the premise that the effect of variation in density will be reflected in the comparative differences in qualities of the thermal environment (indicated by the temperature and wind speed measurements) in the different residential areas of Dhaka. Higher temperatures in the denser parts of the city may be attributed to larger daytime absorptions and slower night-time cooling, and lack of breeze to distribute the unevenness. In conclusion some passive measures are suggested to rectify the negative aspects of the environment