Rationale

The 2022 version of TMS 402/602 (Building Code Requirements and Specification for Masonry Structures) contains a significant overhaul of requirements for veneers, including adhered veneers. These overhauls include development of both a prescriptive design path and an engineered design path. The revisions proposed here update and coordinate the requirements of this standard to align with the prescriptive design requirements for adhered veneer in TMS 402. Units manufactured to comply with the requirements of this standard may still be used when applying the engineered design option of TMS 402, however, doing so may trigger additional testing or design checks as covered in the proposed new notes. For the prescriptive approach, the limitations on unit sizes are different than previous versions of TMS 402. The maximum face dimension requirement (36 inches) has been removed, and instead only includes a maximum area requirement (5 square feet). When units exceed 2.5 square feet, an ‘approved installation method’ must be used. Finally, the requirements for weight per square foot were change from 15 lb/ft2 to 30 lb/ft2 for prescriptive design. This ballot item proposes modifications to align C1670 with the prescriptive design requirements in TMS 402-22. Additional notes are being proposed to aid the user in navigating the differences between the prescriptive and engineered design options of TMS 402.