Analysis of the behaviour of timber construction solutions to interstitial condensation in areas of high relative humidity: Valdivia, Chile

Abstract

High relative humidity in the environment leads to moisture condensation inside the walls of buildings, affecting the durability of materials. Chilean regulations are analyzed, which do not incorporate the study of the behaviour of construction solutions within the same geographical area, even when they are close to large bodies of water. This study seeks to analyze the behaviour of construction solutions for walls of houses in Valdivia, whose primary material is timber, close to bodies of water that can generate interstitial condensation. Outdoor temperature and relative humidity data were recorded in seven locations during August, analyzing the behaviour of four construction solutions under these outdoor conditions. The initial performance of a conventional and a proposed vapour barrier against indoor relative humidity changes are compared. The results show that the construction solutions generate interstitial condensation, the indoor relative humidity as a determinant factor; when implementing a conventional vapour barrier, the phenomenon was drastically reduced. In addition, Kraft paper is proposed as an alternative material with less environmental impact and capable of complying with vapor diffusion resistance limit parameters with acceptable performance. © 2023 by The authors.