Hygrothermal Characteristics of Cold Roof Cavities in New Zealand

The New Zealand Building Code contains minimum durability requirements for components. For roof structures the requirement is 50 years if component structural or 15 it not. Metal claddings are very common in Zealand, and spaces typically not deliberately ventilated. Recently, a number of roofs failing to meet their requirement, lack deliberate ventilation contributory factor some cases. In this paper, we consider failures analyse them using hygrothermal simulation software WUFI® 2D (version 4.1). Using National Research Council Canada’s Guideline on Design Durability Envelopes, evaluate what extent guideline can be used such more complex models. Experimental data from residential dwelling where excessive moisture issues were discovered shortly after occupancy presented. A novel remedial solution daytime-only cavity was trialled, benchmark two-dimensional numerical space 2D. larger set 71 dwellings presented together with relevant climatic conditions. study works towards evidence-based building code changes an example document complicated envelope assemblies.