Wood stud wall

Bearing studs at a spacing under axial load and out-of-plane wind, to NDS 2024 3.6 to 3.10 and 15.4 with ASCE 7-22 combinations, in ASD or LRFD. One stud is designed for its tributary width (the stud spacing); the studs are pinned at the plates.

Inputs of the stud wall #

• Studs: species, grade and size (2x4 to 4x8 dimension lumber), plies per stud, spacing, height and the repetitive member factor Cr (three or more studs at 24 in or less with sheathing, NDS 4.3.9).
• Bracing: Ke (1.0 for studs pinned at the plates), the weak-axis bracing (sheathing fastened to the studs, blocking at a spacing, or none) and whether both stud edges are braced for bending (sheathing or finish on both faces, CL = 1.0). These are your judgment; the usual values are prefilled.
• Loads: axial loads per foot of wall per load type with an eccentricity (its moment adds to the wind moment), and the wind pressure W on the wall (the ASCE 7-22 components and cladding pressure, strength level, acting in both directions).
• Opening: optional. The rough opening width, the head height (the height of the jack studs), the jack and king studs each side, how they are held about the weak axis, the header's size, plies, species and grade (for its bearing on the jacks and the room above the head), and concentrated loads on the header as a reaction at this jamb. One jamb is designed. The wall load over the opening goes through the header to the jacks; the king studs take the wall load of half a stud space beside them and the wind on half the opening and half a stud space, over the full height, and the jacks are not counted in bending, the usual conservative assumption. With the jacks not braced, built-up plies take NDS 15.3 (Kf = 0.6 nailed, 0.75 bolted on the weak axis, and not below the plies as single columns). Sheathing broken by the opening braces one face at most: braced or not is your judgment. The header member is not designed here: the checks list its span, line loads and reactions; copy them into the sawn lumber or glulam beam with the use Header.
• Plates: the species and grade of the plate under the stud and whether Cb applies (the stud bears at least 3 in from the plate end).
• Wind deflection: the wind load factor (IBC Table 1604.3 note f permits 0.42 of the components and cladding load) and the limit height / n (360 plaster or stucco, 240 other brittle finishes, 120 flexible finishes).

Auto-design (editor toolbar) varies the stud size, plies and spacing (12, 16, 19.2, 24 in.); grade when unlocked. Objectives: least wood per foot of wall; lowest cost index. Kept unless you select them: grade. Every other input is kept; see Auto-design.

Checks performed #

Drawings #

The drawing sheet (Drawing sheet / DXF buttons, and the report appendix) shows a representative length of wall: studs (and plies) at the designed spacing, the plate the studs bear on, the stud height, blocking rows when the weak axis is braced by blocking, and the wall loads by type along the top; and the stud section. Wall length, openings, headers, sheathing, the number of top plates and anchorage are not part of the calculation and are not drawn; the wind pressure and the bracing basis are in the sheet notes.

Limitations #

• One opening per calculation; the design of the header member, sills, cripples and their fastening, the sheathing and its fastening, and the in-plane shear of the wall are not covered (see the shear wall module for in-plane design). Force transfer around openings is a later extension.
• Checked against the NDS 2024 text (steps cite section and page): Tables 2.3.2, 2.3.3, 2.3.5, 2.3.6, 4.3.1, 4.3.8, N3; 3.3.3 (CL, RB ≤ 50, now checked when the compression edges are not braced), 3.7.1, 3.9.2, 3.10.2, 3.10.4, 4.3.9 (Cr) and 15.4 (Eq. 15.4-1 with Eq. 15.4-2). Corrected: the plate bearing Fc⊥' takes no λ in LRFD (Table 4.3.1).
• Reference values and the Table 4A / 4B size factors were read against the NDS 2024 Supplement (Chapter 4, 2024-07) on 2026-11-08 and agree. Stud grade wider than 6 in is reported as not feasible (Southern Pine Stud takes the Table 4B "No. 3 and Stud" values at every width).

Verification examples #

Verification status: 33 values compared in 7 examples (5 published, 2 hand calculations from the cited equations): 31 within tolerance, 2 recorded deviations. Code basis: the provisions it uses were read in the target edition.

NDS 2024 has no worked stud wall example. The module is verified against Aghayere & Vigil, Structural Wood Design 2nd ed., Example 5.9 (published values as tabulated in the free calcs.com validation page; its ASCE 7-16 snow load is entered as S / 0.7 and its plate bearing without Cb, as in the example) and hand calculations in closed form of the NDS 2024 equations (backend/tests/test_verify_stud_wall.py):