Wall Framing Calculator

Wall Framing Basics A standard wall frame consists of vertical studs, a bottom plate (sole plate), a top plate (typically doubled), and headers above any openings (doors, windows). Studs are typically 2x4 for interior walls and 2x6 for exterior walls.

Stud Spacing Standard spacing is 16 inches on center (OC), measured from the center of one stud to the center of the next. This spacing aligns with standard 4-foot-wide sheet goods (drywall, plywood, OSB). 24-inch OC spacing is allowed for some non-load-bearing walls and saves material. Load-bearing walls typically require 16-inch OC.

Stud Count Formula Number of studs = ceiling(wall length in inches / spacing) + 1, the +1 being the stud at the far end. Round the division up: a wall that does not divide evenly still needs that end stud, and rounding down leaves you one short at the last bay.

Then add the framing around corners and openings:

• 3 studs per corner, which is the standard three-stud corner that gives drywall something to land on inside and out. Some crews use a two-stud California corner with backing clips instead, which saves lumber and leaves room for insulation.
• 2 king studs + 2 jack studs per opening, door or window.
• 1 cripple stud per 16 inches of opening width above the header, plus the same again below the sill on a window. A 3-foot door needs 3 cripples above it; a 3-foot window needs 3 above and 3 below.

The stud spacing calculator uses the same three-stud corner and the same four studs per opening, so the two pages agree on any wall.

Plates Bottom plate: 1 board the length of the wall. Top plate: 2 boards (double top plate) the length of the wall. Top plate joints must be staggered by at least 4 feet between the two layers. Total plate length = wall length x 3.

Headers Door and window openings need headers, horizontal beams that transfer the load above the opening to the jack studs on each side. Header size depends on the span: up to 4 ft = double 2x6, up to 6 ft = double 2x8, up to 8 ft = double 2x10, up to 10 ft = double 2x12.

Those sizes are for a load-bearing wall carrying a roof. A header in a partition wall is only holding up drywall and can be a single flat 2x4, which is worth knowing before you buy four 2x12s for a closet doorway.