The author's firm was engaged by an insurance company to perform an investigation of the cause and extent of reported damage to wood bowstring roof trusses at a large one-story commercial building in the northeastern United States. Prior to the recent report of damage, extensive repairs had already been installed on the trusses as part of a previous repair campaign reported to date back over twenty years. The current building owner had little knowledge of these repairs and, as such, no information on the repairs or the cause and extent of the damage that motivated the installation of repairs was available for the investigation. The claim of damage that the author's firm was tasked with investigating was limited to damage that occurred subsequent to the previous damage that was addressed by the existing repairs. More specifically, the insurance company needed to know whether any additional damage to the building's roof structure had occurred due to the weight of accumulated ice and snow over the most recent winter season. The subject investigation included site visits to observe the reported damage, identification of wood species and estimation of wood structural grades, a review of available weather data, and limited structural analyses. Using this approach, observed damage to the wood trusses was grouped into two different types, and the cause of each type of damage was assessed to determine whether the damage was caused by the weight of accumulated ice and snow during the time period in question.
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