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Trusses are a structural design element constructed out of steel or wood member to support vertical and lateral loads.


  • Truss specifications must be kept on site.
  • Truss specifications must be stamped and signed by an engineer.
  • The truss configuration meets the design drawings.
  • Ensure that the roofing material(s) have not changed from the original design.
  • Truss bearings as noted on truss specifications.
  • The lumber grade marks and sizes match the design
    specifications and drawings.
  • Required hangers installed per specifications.
  • The connection plate sizes, gauges and locations are per specifications.
  • The truss bracing has been completed as noted and shown on the truss engineer’s plans.
  • Ganged trusses nailed off per manufacturer’s specifications.
  • Fasteners and hardware for pressure preservative and fire-retardant-treated wood shall be of hot-dipped galvanized steel, stainless steel, silicon bronze or copper. 

A design professional is responsible for the design of all the truss connections to the structure and verifying that all interactions are adequately addressed and that the design conforms to the adopted codes.

  • Truss analysis and design drawings must be stamped by a Washington State licensed engineer.
  • Shop drawings must have a review stamp by the engineer of record or architect of record stating trusses are compatible with the design of the building.
  • Truss specifications may be submitted as a deferred submittal item, please see our Deferred Submittals Tip Sheet for more information.


  • IBC 2015 – International Building Code
  • ASTM D 5055 – Standard Specification for Establishing and Monitoring Structural Capacities of Prefabricated Wood I-Joists
  • SJI – Steel Joist Institute Standards & Specifications
  • ANSI/TPI-1 – National Design Standard For Metal Plate Connected Wood Truss Construction


Sample Truss Design


Sample Truss Placement Diagram

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