What is the thickness of standard stud walls?

The thickness of standard stud walls is typically 4 inches. This dimension is based on the use of 2x4 lumber for the studs, which are commonly used in residential construction. Although the nominal size of the lumber is 2x4 inches, the actual dimensions after drying and planing are roughly 1.5 inches by 3.5 inches. When two of these studs are placed side by side, the total thickness adds up to 3.5 inches, but when considering the drywall or sheathing added on both sides, it brings the total thickness of the wall to about 4 inches.

In constructing walls, this standard thickness helps provide structural integrity while also maintaining space efficiency in interior design. It's also important to note that while different wall assemblies can use various materials and thicknesses for specific applications, the standard stud wall thickness predominantly stays at 4 inches in most residential situations.