Mitigating Thermal/Solar Heat Gains on Pavements and Its Influence on the Environment

Abstract

With the vast quantity of natural vegetation being replaced by heat absorption materials due to urbanization, incident solar radiation is seen to be one of the most prominent heat sources. This increases the storage of sensible heat on these materials which accumulates heat impinged on the surrounding surfaces and is entrapped within the urban canyon. A large percent of the urban fabric is seen to be covered by pavements. It is therefore likely that the outdoor thermal environment is most influenced by the surface temperature of pavements increase the overall air temperature as well as the surface temperatures of the wall – hence temperature transfers to the interior, contributing to the operational indoor temperatures. This paper presents a review on paved surfaces aimed at studying the process of thermal heat gains of pavement materials with respect to their surface temperature under continual exposure to solar radiation. An experiment was carried out on three pavement materials to determine its surface temperature during the whole period of the day. Findings show excessive heat on paved surfaces especially during the day. Cool pavements (Porous/ high solar reflectance) however were significantly lower in surface temperature than the conventional impermeable pavements for all paved materials sampled because of its high reflectance and porous nature. This review analysis shows that an improvement on the thermal properties of outdoor spaces can be expected if the solar reflectance of paved surfaces is increased by retrofitting and the porosity be a key feature on the surface of pavements.

Keywords: Pavements, Heat gain, Surface Temperature, Solar Radiation.