Development of a post-occupancy assessment method system to evaluate the durability of external cladding of prefabricated timber panels

Abstract

The global environmental crisis has increased interest in sustainability within the construction sector. Timber construction is a viable option, but concerns about its short- and long-term durability still need to be addressed. This article presents a developed Assessment Method System for evaluating the durability of external cladding of prefabricated timber panels. First, an Assessment Form was created to map and catalogue the panels' state of conservation based on on-site observations. The form includes an evaluation worksheet that lists and classifies the frequency and intensity of six defects: 1) Rotted Parts; 2) Detachments; 3) presence of Wood Knots; 4) Cracks and/or Broken Parts; 5) Wood planks; and 6) Sill Failure. On-site observations were conducted in case studies to complete the Assessment Form and document the condition of the specific building's timber panels. The collected data were then tabulated and used as a basis for the panel's durability diagnosis. Comparative studies were then carried out between five case studies to validate the Assessment Method System. As a result, the work highlights aspects, such as material, design, and execution, of the durability of timber wall panels built in specific conditions. In that sense, the Assessment Method was a fundamental tool to stress how these aspects were carried out. In addition, this can enhance the scientific basis of timber architecture and aid architects and researchers in making informed decisions regarding optimising future timber projects.