The use of ceramic filled white elastomeric acrylic coatings to reduce the thermal load of buildings with low slope roofs

Resumo

Commercial and industrial buildings such as shopping centers, supermarkets, airports and sheds are in general some of the construction types characterized as having large roof surfaces compared to external wall surfaces. When climatized artificially, these buildings become great consumers of electrical energy. In order to reduce this energy consumption, insulation materials such as polyurethane and fiberglass wool are added to it. This is the mass insulation approach. Notwithstanding the effectiveness of such procedure, cost and environmental issues has been considered as limited factors to his widespread utilization. In this paper, it is analyzed the effect of the application of a selective ceramic filled white elastomeric acrylic coating with very high solar reflectance and thermal emittance for thermal radiation (5 to 30 μm) on the surface temperature of the roof and heat flux that crosses a mass insulated roof of a artificially climatized building. The study was carried out from a mathematical model that took into account the following parameters: time varying solar radiation and outside air temperature and additionally the properties of the construction materials of the roof. The results obtained demonstrate the good performance of selective coatings concerning the temperature of the roof and the heat flux reduction.