In WUI zones, protect openings from wind-blown embers

Description

Homes in a Wildland-Urban Interface (WUI) area should be detailed to resist ember intrusion: vents fitted with 1/8-inch (or finer) noncombustible mesh, no exposed eave or soffit cavities, tempered or multi-pane glazing, no combustible siding within the first 6 inches above grade, and ember-resistant roof coverings (Class A) per ICC IWUIC + IRC R337.

Why this exists

Most home losses in wildfire are caused by wind-blown embers rather than direct flame contact — embers land in vents, attic spaces, gutters, and combustible siding gaps and start the home from inside. Ember-resistant detailing is the most effective WUI mitigation.

Categories

Source

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.

Plan symbols this applies to

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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