R603.2 Structural Framing
Load-bearing cold-formed steel framing shall have a metallic coating complying with ASTM A1003 and one of the following:
- A minimum of G 60 in accordance with ASTM A653.
- A minimum of AZ 50 in accordance with ASTM A792.
Load-bearing cold-formed steel wall framing members shall comply with Figure R603.2.3(1) and with the dimensional and thickness requirements specified in Table R603.2.3. Additionally, C-shaped sections shall have a minimum flange width of 15/8 inches (41 mm) and a maximum flange width of 2 inches (51 mm). The minimum lip size for C-shaped sections shall be 1/2 inch (12.7 mm). Track sections shall comply with Figure R603.2.3(2) and shall have a minimum flange width of 11/4 inches (32 mm). Minimum Grade 33 ksi steel shall be used wherever 33 mil and 43 mil thicknesses are specified. Minimum Grade 50 ksi steel shall be used wherever 54 and 68 mil thicknesses are specified.
LOAD-BEARING COLD-FORMED STEEL STUD SIZES AND THICKNESSES
|MEMBER DESIGNATIONa||WEB DEPTH (inches)||MINIMUM BASE STEEL THICKNESS mil (inches)|
|350S162-t||3.5||33 (0.0329), 43 (0.0428), 54 (0.0538)|
|550S162-t||5.5||33 (0.0329), 43 (0.0428), 54 (0.0538), 68 (0.0677)|
For SI: 1 inch = 25.4 mm; 1 mil = 0.0254 mm.
- The member designation is defined by the first number representing the member depth in hundredths of an inch, "S" representing a stud or joist member, the second number representing the flange width in hundredths of an inch, and the letter "t" shall be a number representing the minimum base metal thickness in mils.
Load-bearing cold-formed steel framing members shall have a legible label, stencil, stamp or embossment with the following information as a minimum:
- Manufacturer's identification.
- Minimum base steel thickness in inches (mm).
- Minimum coating designation.
- Minimum yield strength, in kips per square inch (ksi) (MPa).
Web holes in wall studs and other structural members shall comply with all of the following conditions:
- Holes shall conform to Figure R603.2.6.1.
- Holes shall be permitted only along the centerline of the web of the framing member.
- Holes shall have a center-to-center spacing of not less than 24 inches (610 mm).
- Holes shall have a web hole width not greater than 0.5 times the member depth, or 11/2 inches (38 mm).
- Holes shall have a web hole length not exceeding 41/2 inches (114 mm).
- Holes shall have a minimum distance between the edge of the bearing surface and the edge of the web hole of not less than 10 inches (254 mm).
Framing members with web holes not conforming to the above requirements shall be reinforced in accordance with Section R603.2.6.2, patched in accordance with Section R603.2.6.3 or designed in accordance with accepted engineering practice.
Web holes in wall studs and other structural members not conforming to the requirements in Section R603.2.6.1 shall be permitted to be patched in accordance with either of the following methods:
- 1.1. The depth of the hole, measured across the web, exceeds 70 percent of the flat width of the web.
- 1.2. The length of the hole measured along the web exceeds 10 inches (254 mm) or the depth of the web, whichever is greater.
- Web holes not exceeding the dimensional requirements in Section R603.2.6.3, Item 1, shall be patched with a solid steel plate, stud section or track section in accordance with Figure R603.2.6.3. The steel patch shall, as a minimum, be the same thickness as the receiving member and shall extend not less than1 inch (25 mm) beyond all edges of the hole. The steel patch shall be fastened to the web of the receiving member with No. 8 screws spaced not more than 1 inch (25 mm) center-to-center along the edges of the patch with a minimum edge distance of 1/2 inch (12.7 mm).