GuidelineRecommended
Shear wall aspect ratio: 3.5:1 maximum for wood structural panel shear walls
HUD RSDG §6.4Description
Wood structural panel (plywood / OSB) shear walls shall have an aspect ratio (height/length) not exceeding 3.5:1 for wind, 2:1 for seismic with limiting allowable unit shear. Taller-than-wide shear walls lose lateral capacity rapidly.
Why this exists
Aspect ratio governs the overturning moment + uplift the shear wall must resist. Excessive ratios concentrate uplift at end studs beyond practical hold-down capacity.
Measurements
| Property | Operator | Value | Unit | Note |
|---|---|---|---|---|
windAspect | max | 3.5 | ratio | Max height/length ratio for wind |
seismicAspect | max | 2 | ratio | Max height/length ratio for seismic |
Categories
Structure
Source
HUD (US Department of Housing and Urban Development)no manifest entry
Residential Structural Design Guide, Second Edition (2nd ed)
Section: Chapter 6, §6.4
Published 2000-01-01 · last verified 2026-05-10
Solver enforcement
Browsable only — the solver does not currently enforce this directive (no spec-level data to check against). This entry exists so the architect personas can cite it in conversation and the user can read what the rule says.
Related directives
- Continuous load path from roof to foundation · HUD RSDG §2.4
- Residential structural reliability targets 1-in-100 to 1-in-1000 annual probability of failure · HUD RSDG §2.5
- Residential floor live load: 40 psf minimum (30 psf sleeping rooms) · HUD RSDG §3.4
- Wind load design uses ASCE 7 basic wind speed for the locality · HUD RSDG §3.6
- Ground snow load for Virginia: 25 psf eastern, up to 40 psf western mountains · HUD RSDG §3.7
Last reviewed 2026-05-10.