Análise da eficiência de uma tinta emulsionável com adição de fragmentos de alumínio na regulação térmica de edificações por meio da refletância da radiação solar

Abstract

This study presents a comparative analysis between a standard white exterior paint, known for reflecting part of the solar radiation in the infrared spectrum, and the same paint formulation enhanced with aluminum fragments. The aim is to assess whether the addition of this metallic component increases reflectance, thereby improving thermal comfort in buildings while utilizing an abundant and low-cost material. The research was carried out using a masonry prototype with an area of 3.62 m², built in the city of Paulo Afonso, Bahia, located in Brazil’s northeastern semi-arid region, which is characterized by high temperatures even during the winter. The external walls were painted with both formulations, and temperatures of the indoor and outdoor environments, as well as internal and external surfaces, were recorded at 07:00, 12:00, and 17:00 over two days for each paint type. The average values were compared to evaluate thermal variations. Results showed that the aluminum-enriched paint performed better in reducing internal surface temperature, with a difference of up to 5.05°C compared to the external temperature on walls exposed to direct sunlight.