Standard Width of a Stud in a House

Standards

• The thousands of local and state building authorities in the United States could have a thousand standards for the measurements of studs in a house. But all base their information on the International Residential Code, a comprehensive set of construction regulations maintained by the nonprofit International Code Council. When founded in 1994, the council streamlined then-existing codes and resolved any conflicts.

Bearing Walls

• The stud sizes for all types of wood wall framing include 2-by-4, 3-by-4, 2-by-5, and 2-by-6, all specified in inches. Bearing walls, also called load-bearing walls, are those that support the weight of the house -- for example, by holding up the ceiling or the floor. These are the strongest walls of the house, and their removal can cause the structures to collapse. Stud capabilities vary by the type of load-bearing wall and the maximum spacing of the stud. For example, all the sizes are allowed for laterally unsupported 10-foot high studs at 24 inches when supporting a roof-ceiling assembly. When supporting one floor, and a roof-ceiling assembly, a 2-by-4 can be spaced at 16 inches for 10-foot high studs. All other widths of the same height require 24-inch spacing.

Nonbearing Walls

• Nonbearing walls are those that do not support structures of the house, such as those used to partition a space into several rooms. They can be removed and repositioned as necessary without the collapse of the house. As with bearing walls, stud sizes affect laterally unsupported stud height and maximum spacing. A 2-by-3 maxes out at 10 feet spaced at 16 inches. A 2-by-4 and 3-by-4 are at 14 feet at 24 inches. A 2-by-5 is at 16 feet at 24 inches and a 2-by-6 is at 20 feet with 24 inches.

Steel

• The widest part of a steel stud is called the web, while the depth is indicated by two flanges with a lip. Their measurements for load-bearing walls vary according to the member designation, which is a series of numbers used to identify stud measurements. For example, designation 350S162-t shows a web depth of 3.5 inches, the letter “S” for stud, a minimum flange width of 1.625 inches, and the letter “t,” which represents thickness. Designation 550S162-t refers to a stud with the same measurements, except for the web depth, which runs 5.5 inches will. In both cases, the maximum flange with is 2 inches, and the minimum lip size is 0.5 inches.