Truss Failure And Repair
Question:
I am a professional engineer looking for information concerning the failure of metal plate connected wood trusses and methods of repair. I am looking for this information with regard to developing recommendations for the repair of truss systems in the floor structures of two-story multi-family dwellings. I see frequent failure of truss systems of this type in both in bending and due to catastrophic failure at the gussets.
Answer:
Most truss repairs that are generated during the construction phase involve lumber scabs over broken webs and chords or plywood/OSB gussets over damaged plates or joints. These are generated following the design principles outlined in The American Wood Council’s National Design Specification for Wood Construction (NDS).
One option may be to contact the truss manufacturer and have their engineering support supply the repair details for you.
What is of more concern, though, are these frequent catastrophic failures that you describe. What is causing this? Are the trusses being overloaded? Often, trusses are overloaded with stacks of construction materials (drywall, plywood, etc.) shortly after installation and they can be permanently damaged even though they were designed and manufactured correctly.