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CRC R327 — Marin Wildland-Urban Interface

Updated May 18, 2026
Ignition-resistant exterior construction mandatory in Marin WUI zones; Class A roof, non-combustible siding, ember-resistant vents.

CRC Chapter 7A / R327 governs construction in California State Responsibility Areas (SRA) and Marin Local Responsibility Areas (LRA-VHFHSZ). Most of Marin County is mapped as Very High Fire Hazard Severity Zone. Requirements: Class A roof assembly, non-combustible or ignition-resistant siding, dual-pane tempered glazing within 10 ft of grade, 1/8 inch mesh ember-resistant vents, fully enclosed eaves. Defensible space (PRC 4291) extends 100 ft.

TAGS
marinWUIwildfireChapter-7Adefensible-space
DETAILS
edition
2022
adopted by
["ca-marin","ca-marin-county"]
code system
CRC
confidence tier
primary
jurisdiction label
Marin County, CA
SOURCES
🔗https://codes.iccsafe.org/codes/california/CARC2022P1
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