Important Clarification on Special Inspections of Trusses
For anyone using UpCodes or the printed version of the 2018 IBC, it is important to pay close attention to the errata when it comes to Section 1705.5.2 Metal-Plate-Connected Wood Trusses Spanning 60 Feet or Greater.
In a February 2018 article, we pointed out that in April 2016, proposal S138-16 was introduced by a representative of the National Council of Structural Engineers’ Association (NCSEA) during the 2018 IBC code development process in Louisville, Kentucky. The proposal sought to amend Chapter 17 of the 2015 IBC and add language requiring special inspections of roof trusses over 60 inches high as follows:
Special inspections of wood trusses with overall heights of 60 inches (1524 mm) or greater shall be performed to verify that the installation of the permanent individual truss member restraint/bracing has been installed in accordance with the approved truss submittal package. For wood trusses with a clear span of 60 feet (18 288 mm) or greater, the special inspector shall verify during construction that the temporary installation restraint/bracing is installed in accordance with the approved truss submittal package.
That proposal was ultimately withdrawn by NCSEA in favor of working with SBCA to draft a better solution to their concerns regarding permanent web member lateral restraint and diagonal bracing. Unfortunately, the withdrawal of the proposal is not reflected in the printed editions of the codes, but rather was fixed through a subsequent errata. This errata is not necessarily picked up by UpCodes either, so it’s important to play close attention to the correct wording of Section 1705.5.2:
Where a truss clear span is 60 feet (18288 mm) or greater, the special inspector shall verify that the temporary installation restraint/bracing and the permanent individual truss member restraint/bracing are installed in accordance with the approved truss submittal package.
Fortunately, SBCA and NCSEA have developed a joint proposal for the 2021 IBC that brings better clarity within the IBC on this issue.