Planejamento da vida útil na construção civil: uma metodologia para a aplicação da Norma de Desempenho (NBR 15575) em sistemas de revestimentos de pintura

Abstract

ABSTRACT This paper is a theoretical study about the service-life planning in buildings and civil engineering applied to facade paint coating systems, as well as an experimental research applied to samples in distinct substrates and painted with four different colors. In this study were considered the different climatic characteristics of the metropolitan region of Belo Horizonte, Minas Gerais. It aims to present the complexity of a service-life prediction methodology and to verify the presented system behavior during a given period. The service life planning is one of the strategies used in some countries to obtain an increased performance within the construction industry, which has been studied since the 90s. In Brazil, this methodology has reached only a minor extent, although there is an attempt to insert it as a prerequisite in the Standard Performance (ABNT NBR 15575). Due to the need of a more meticulous study about the service life planning, this paper proposed researching the European method and checking the existing processes. Subsequently, we sought to apply a methodology for the service life prediction to eight samples that were painted with four different colors - with organic and inorganic pigment - and exposed to natural weathering. Following the exposure period of the samples, were analyzed properties that reflect the aesthetic function (gloss loss and color change) and the durability of the system (abrasion resistance - or washability - and adhesion) as well as a possible absorbance variation of the paint coating during the test, all directly reflecting on the building thermal performance. At the end of this paper, we intend to show the complexity of a service life planning and to present a method of performance assessment in a paint coating system aiming to meet Performance Standard ABNT NBR 15575 on this subject-matter.