Methodology for service life prediction of window frames

Window frames are an important element of buildings, with an enormous impact on the thermal performance and interior comfort conditions of buildings. Knowledge regarding the service life of window frames is extremely relevant, aiding the adoption of adequate solutions in the design and maintenance stages. This study proposes a methodology for the service life prediction of window frames, based on the visual inspection of 182 case studies, in-use conditions, in which the degradation phenomena and various characteristics of window frames are surveyed. This information is converted into degradation curves, which express the evolution of the degradation of window frames over time, allowing their service life to be estimated, as well as the influence of their characteristics on their durability. For aluminum and wooden frameworks, estimated service lives of 37.6 and 27.3 years are obtained. These results reveal that the window exposure conditions and the users’ behaviors have a substantial impact on the degradation of window frames.