An Update on Problems Associated with Metal-Plate-Connected

Our practice in forensic engineering includes wood structures. Over time, we have received many calls about buildings with metal-plate-connected wood-roof trusses (trusses). Trusses are used extensively, both within the housing industry and in commercial buildings, and their engineering is fine tuned and precise. At the Second Forensic Congress in 2000, and based upon experiences designing and investigating the use of engineered wood trusses, I presented a view of the problems I saw. Many of those problems grew out of the difference between how trusses actually work and how the builders using them understood them. Other problems seemed to grow directly out of the nature of the design and construction industry and in the way trusses and their design fit into the existing contracting process. This paper provides an update on the use of manufactured trusses, changes in legislation and codes that affect their design and use, and problems that remain.