Why doesn’t UltraSTEEL™ meet ASTM C-645?
• The performance of products produced with the UltraSTEEL™ technologies are so superior that it performs equally with industry standard ASTM and SSMA limiting height charts. The reduction in material thickness from 0.0179″ to 0.015″ for 25-gauge equivalent studs is less than the minimum decimal required to generically comply with ASTM C-645. However, this is not an issue since ASTM C-645 anticipated developing technology such as UltraSTEEL™ and clearly provides an alternative mechanism for compliance in section 5.0, which reads: • 5.0 Dimensions and Permissible Variations 5.1 Studs and rigid furring channels shall have a configuration and steel thickness such that the system in which they are used will carry the design transverse loads without exceeding either the allowable stress of the steel or the allowable design deflection. Main beams and cross furring of grid suspension systems shall be limited to a deflection of L/240. The manufacturer shall supply sufficient data for calculati
