Analysis of fungal growth on different coatings applied to lightweight systems

Abstract

Walls are essential for buildings because they delimitate surroundings while influencing durability. Regarding the development of buildings, lightweight systems have emerged, which usually have internal closures of gypsum boards with several coating options. The south region of Brazil has subtropical climate, which promotes the development of fungi, which harm human health in buildings. Therefore, a test was performed according to ASTM D3273-12, for the periods of 4 and 10 weeks, to assess the resistance to growth of fungi on gypsum boards with coatings of acrylic paint, epoxy paint, smooth speckle, textured speckle and waterproofing polymer. Results showed more severe deterioration of the samples coated with acrylic paint, and at 10 weeks the worst case reached a grade below 4 according to the classification of the standard and provided the development of the Aspergillusand Aureobasidiumfungi, whereas the epoxy paint sample favored the growth of genera Penicilliumand Aspergillus. The tests also showed significant differences in mold damage for the periods of 4 weeks (recommended by the standard) and 10 weeks (timespan of this study).