Durability of light wood frame constructive system: study of interstitial condensation

Abstract The Light Wood Frame (LWF) construction system has been increasingly researched and applied in Brazilian buildings, driven by the recent publication (mid-2023) of the Brazilian standard "Light Wood Frame Buildings" and by its potential for industrialization and reduced environmental impact. This reduction is mainly due to the system's ability to capture biogenic carbon through the timber used in its frames. However, a critical consideration for implementing this system in Brazilian buildings is ensuring compliance with durability requirements, particularly in addressing the risk of high humidity levels within walls or between floors, which can result from interstitial condensation. This article aims to analyze the occurrence of interstitial condensation in the walls of buildings constructed with the LWF system in the Brazilian Bioclimatic Zone 1M. To achieve this, a bibliographic review was conducted, the characteristics of the wall construction components were gathered, and computer simulations were performed using EnergyPlus and WUFI Pro 6.5 software. For the configuration studied, no interstitial condensation was detected in the internal bracing layer of the wall, suggesting a good natural drainage capacity of the construction system in the evaluated bioclimatic zone.