CWUIC · California Wildland-Urban Interface Code
Local implementation, applicability & related regulations
This hub summarizes where the CWUIC applies, how local jurisdictions implement and amend it, and which California regulations it coordinates with.
Last reviewed: July 6, 2026
Overview
This area of the California Wildland‑Urban Interface Code (CWUIC) explains where the code applies and how local jurisdictions adopt, amend, and coordinate its provisions with other California regulations. The CWUIC’s purpose and broad scope are set out in §1.1.2 (Purpose) and §1.1.3 (Scope), which establish minimum construction and development requirements to reduce life‑and‑property loss from wildfire across State Responsibility Areas (SRA) and applicable Local Responsibility Areas (LRA) .
Local implementation centers on the code’s chapter structure and the adoption/amendment process: Chapters 3–6 cover designation of WUI areas (§302), area‑level requirements and applicability (see §401–§402), building construction rules (Chapter 5) and fire‑protection requirements (Chapter 6) that local agencies use to set or extend standards in their jurisdictions . Local amendments must follow prescribed findings and filing procedures (see §1.1.8) so changes are justified by climatic, topographic, or geological conditions and properly filed with state agencies .
The CWUIC is used alongside other California regulations: certain Title 14 and Title 19 provisions are reprinted for user convenience and the code cross‑references the California Fire Code (for example, water‑supply/fire‑flow provisions) and statutory defensible‑space requirements such as Public Resources Code 4291 referenced in §604.1 (maintenance of defensible space) . Enforcement is shared between the State Fire Marshal and local fire authorities as described in the administration sections of the code .
In this section
Code references
Grounded in the retrieved California Wildland-Urban Interface Code — click a citation to read the verbatim passage:
CWUIC § 1.1.2 High relevance — show source text
1.1.2 Purpose. The purpose of this code is to establish minimum requirements to reduce the likelihood of life and property loss due to a wildfire through the use of performance and prescriptive requirements for construction and development in all Fire Hazard Severity Zones in State Responsibility Areas (SRA), and Local Responsibility Areas (LRA) designated as a Very High Fire Hazard Severity Zone, and increase the ability of buildings located in any Fire Hazard Severity Zone within State Responsibility Areas (SRA), or Wildland-Urban Inter- face (WUI) Areas, to resist the intrusion of flames or burning embers projected by a vegetation fire and contributes to a systematic reduction in conflagration losses and reduce the likelihood of life and property loss due to a wildfire.
1.1.3 Scope. The provisions of this code shall apply to the construction, alteration, movement, enlargement, replacement, repair, equip- ment, use and occupancy, location, maintenance, removal, and demolition of every building or structure or any appurtenances connected or attached to such building structures throughout the State of California.
This code establishes regulations affecting or relating to buildings, structures, processes, premises, and a reasonable degree of life and property safeguards regarding: 1. The hazard of fire and explosion arising from the storage, handling, or use of structures, materials, or devices. 2. Conditions hazardous to life, property, or public welfare in the use or occupancy of buildings, structures, or premises. 3. Fire hazards in the buildings, structures, orp on-premises from use of, occupancy of, or operation. 4. Matters related to the construction, extension, repair, alteration, or removal of fire suppression or alarm systems. 5. Conditions affecting the safety of firefighters and emergency responders during emergency operations.
1.1.4 Appendices. Provisions contained in the appendices of this code shall not apply unless specifically adopted by a state agency or adopted by a local enforcing agency in compliance with Health and Safety Code, Section 18901 et. seq. for Building Standards Law, Health and Safety Code, Section 17950 for State Housing Law and Health and Safety Code, Section 13869.7 for Fire Protection Districts. See Section 1.1.8 of this code.
1.1.5 Referenced codes. The codes, standards, and publications adopted and set forth in this code, including other codes, standards, and publications referred to herein are, by title and date of publication, hereby adopted as standard reference documents of this code. When this code does not specifically cover any subject related to building design and construction, recognized architectural or engineer- ing practices shall be employed. The National Fire Codes, standards, and the Fire Protection Handbook of the National Fire Protection Association are permitted to be used as authoritative guides in determining recognized fire prevention engineering practices.
1.1.6 Nonbuilding standards, orders, and regulations. Requirements contained in the California Wildland-Urban Interface Code, or in any other referenced standard, code, or document, which are not building standards as defined in Health and Safety Code, Section 18909 shall not be construed as a building standard. The nonbuilding standards contained herein are applicable in the wildland inter- face areas and can be cited as a section of this code, or where the section is identified on the tagline by the source document, the provision can be cited under the source document.
1.1.7 Order of precedence and use.
CWUIC § 1-2 High relevance — show source text
CHAPTER TOPICS Col2 CHAPTER SUBJECT 1-2 Administration and Definitions 3-4 Wildland-Urban Interface Area Designation and Requirements 5 Building Construction Regulations 6 Fire Protection Requirements 7 Referenced Standards Appendices A-I Adoptable and Informational Appendices Chapter 1 Scope and Administration.
Chapter 1 establishes the limits of applicability of the code and describes how the code is to be applied and enforced. The provisions of Chapter 1 establish the authority and duties of the code official appointed by the authority having jurisdiction and also establish the rights and privileges of the design professional, contractor and property owner.
Chapter 2 Definitions.
Chapter 2 is the repository of the definitions of terms used in the body of the code. The user of the code should be familiar with and consult this chapter because the definitions are essential to the correct interpretation of the code and because the user may not be aware that a term is defined.
Chapter 3 Wildland-Urban Interface Areas.
Chapter 3 provides for the fundamental aspect of applying the code—the legal declaration and establishment of wildland-urban interface areas within the adopting jurisdiction, mapping of the area, periodic review and updates.
Chapter 4 Wildland-Urban Interface Area Requirements.
The requirements of Chapter 4 apply to all occupancies in the wildland-urban interface and pertain to all of the following:
Fire service access to the property that is to be protected, including fire apparatus access roads and off-road driveways.
Premises identification.
Key boxes to provide ready access to properties secured by gated roadways or other impediments to rapid fire service access.
Fire protection water supplies, including adequate water sources, pumper apparatus drafting sites, fire hydrant systems and system reliability.
Fire department access to equipment such as fire suppression equipment and fire hydrants.
Chapter 5 Special Building Construction Regulations.
The regulations in Chapter 5 establish minimum standards for the location, design and construction of buildings and structures based on construction within a Fire Hazard Severity Zone or a Wildland-Urban Interface (WUI) Area.
The construction provisions of Chapter 5 are intended to supplement the requirements of the California Building Code and Califor- nia Residential Code and address mitigation of the unique hazards posed to buildings by wildfire and to reduce the hazards of building fires spreading to wildland fuels. This is accomplished by requiring ignition-resistant construction materials.
Chapter 6 Fire Protection Requirements.
Chapter 6 contains additional requirements for development and construction in Local Responsibility Areas (LRA) designated as Very High Fire Hazard Severity Zones and areas designated by the State Fire Marshal as State Responsibility Areas (SRA). While many of these provisions are found in Title 14 and Title 19 of the California Code of Regulations, they are replicated here for the code user. The local jurisdiction has the authority to apply the same regulations to LRA when the regulations are adopted by local ordinance.
The requirements in this chapter reference the process for adoption of Very High Fire Hazard Severity Zones in the LRA; criteria for evaluating existing subdivisions that are at significant fire risk and are without an adequate secondary egress; and criteria for fire safety provisions required in the Safety Element of a city or county General Plan.
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CWUIC § 102.4 High relevance — show source text
Chapter 5 Special Building Construction Regulations.
The regulations in Chapter 5 establish minimum standards for the location, design and construction of buildings and structures based on construction within a Fire Hazard Severity Zone or a Wildland-Urban Interface (WUI) Area.
The construction provisions of Chapter 5 are intended to supplement the requirements of the California Building Code and Califor- nia Residential Code and address mitigation of the unique hazards posed to buildings by wildfire and to reduce the hazards of building fires spreading to wildland fuels. This is accomplished by requiring ignition-resistant construction materials.
Chapter 6 Fire Protection Requirements.
Chapter 6 contains additional requirements for development and construction in Local Responsibility Areas (LRA) designated as Very High Fire Hazard Severity Zones and areas designated by the State Fire Marshal as State Responsibility Areas (SRA). While many of these provisions are found in Title 14 and Title 19 of the California Code of Regulations, they are replicated here for the code user. The local jurisdiction has the authority to apply the same regulations to LRA when the regulations are adopted by local ordinance.
The requirements in this chapter reference the process for adoption of Very High Fire Hazard Severity Zones in the LRA; criteria for evaluating existing subdivisions that are at significant fire risk and are without an adequate secondary egress; and criteria for fire safety provisions required in the Safety Element of a city or county General Plan.
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The chapter includes mitigation strategies to reduce the hazards of fire originating within a structure spreading to wildland and fire originating in wildland spreading to structures.
Chapter 7 Referenced Standards.
Chapter 7 lists all of the product and installation standards and codes that are referenced throughout Chapters 1 through 6 and includes identification of the promulgators and the section numbers in which the standards and codes are referenced. As stated in Section 102.4, these standards and codes become an enforceable part of the code (to the prescribed extent of the reference) as if printed in the body of the code.
Appendix A General Requirements.
Appendix A, while not part of the code, can become part of the code when specifically included in the adopting ordinance. Its purpose is to provide fire-protection measures supplemental to those found in Chapter 6 to reduce the threat of wildfire in a wildland-urban interface area and improve the capability for controlling such fires. This appendix includes detailed requirements for vegetation control; the code official’s authority to close wildland-interface areas in times of high fire danger; control of fires, fireworks usage and other sources of ignition; storage of hazardous materials and combustibles; bans on the dumping of waste materials and ashes and coals in wildlandurban interface areas; protection of pumps and water supplies; and limits on temporary uses within the wildland-urban interface area.
Appendix B Vegetation Management Plan.
Appendix B, while not part of the code, can become part of the code when specifically included in the adopting ordinance. Its purpose is to provide criteria for submitting vegetation management plans, specifying their content and establishing a criterion for considering vegetation management as being a fuel modification.
Appendix C Community Wildland-Urban Interface (WUI) Fire Hazard Evaluation Framework.
CWUIC § 4-1 High relevance — show source text
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4 WILDLAND-URBAN INTERFACE AREA REQUIREMENTS
User notes:
About this chapter: Chapter 4 provides requirements that apply to all occupancies in the wildland-urban interface and pertain to all of the following:
Fire service access to the property that is to be protected, including fire apparatus access roads and off-road driveways.
Premises identification.
Key boxes to provide ready access to properties secured by gated roadways or other impediments to rapid fire service access.
Fire protection water supplies, including adequate water sources, pumper apparatus drafting sites, fire hydrant systems and system reliability.
Fire department access to equipment such as fire suppression equipment and fire hydrants.
SECTION 401—GENERAL
401.1 Scope. Wildland-urban interface areas shall be provided with emergency vehicle access and water supply in accordance with this chapter.
401.2 Objective. The objective of this chapter is to establish the minimum requirements for emergency vehicle access and water supply for buildings and structures located in the wildland-urban interface areas.
401.3 General safety precautions. General safety precautions shall be in accordance with this chapter. See also Appendix A.
SECTION 402—APPLICABILITY
402.1 Subdivisions. Subdivisions shall comply with Sections 402.1.1 and 402.1.2.
402.1.1 Access. New subdivisions, as determined by this jurisdiction, shall be provided with fire apparatus access roads in accordance with the California Fire Code; the California Code of Regulations, Title 14, Division 1.5, Chapter 7, Subchapter 2, Article 2; and access requirements in accordance with Section 403.
402.1.2 Water supply. New subdivisions as determined by this jurisdiction shall be provided with water supply in accordance with Section 507 of the California Fire Code; California Code of Regulations, Title 14, Division 1.5, Chapter 7, Subchapter 2, Article 4; and Section 404.
402.1.2.1 Parcel map approval. Water supply requirements shall apply in the tentative and parcel map process when new parcels are approved by the local jurisdiction.
402.2 Individual structures. Individual structures shall comply with Sections 402.2.1 and 402.2.2.
402.2.1 Access. Individual structures hereafter constructed or relocated into or within wildland-urban interface areas shall be provided with fire apparatus access in accordance with the California Fire Code; the California Code of Regulations, Title 14, Division 1.5, Chapter 7, Subchapter 2, Subsection 1273; and Section 403 .
402.2.2 Water supply. Individual structures hereafter constructed or relocated into or within wildland-urban interface areas shall be provided with a conforming water supply in accordance with the California Code of Regulations, Title 14, Division 1.5, Chapter 7, Subchapter 2, Article 4; California Fire Code Section 507; and Section 404.
CWUIC § 18941.5 High relevance — show source text
Local modifications shall comply with Health and Safety Code, Section 18941.5 for Building Standards Law, Health and Safety Code, Section 17958 for State Housing Law or Health and Safety Code, Section 13869.7 for Fire Protection Districts.
1.1.8.1 Findings and filings. 1. The city, county, or city and county shall make express findings for each amendment, addition, or deletion based upon climatic, topographical, or geological conditions. Exception: Hazardous building ordinances and programs mitigating unreinforced masonry buildings. 2. The city, county, or city and county shall file the amendments, additions, or deletions expressly marked and identified as to the applicable findings. Cities, counties, cities and counties, and fire departments shall file the amendments, additions, or deletions, and the findings with the California Building Standards Commission at 2525 Natomas Park Drive, Suite 130, Sacramento, CA 95833.
3. Findings prepared by fire protection districts shall be ratified by the local city, county, or city and county and filed with the California Department of Housing and Community Development, Division of Codes and Standards, P.O. Box 1407, Sacra- mento, CA 95812-1407 or 2020 West El Camino Avenue, Suite 250, Sacramento, CA 95833-1829.
1.1.8.2 Locally adopted energy standards—California Energy Code, Part 6. In addition to the provisions of Section 1.1.8.1 of this Part, the provisions of this section apply to cities, counties, and city and county amending adopted energy standards affecting build- ings and structures subject to the California Energy Code, Part 6.
Applicable provisions of Public Resources Code Section 25402.1 and applicable provisions of Chapter 10 of the California Adminis- trative Code, Part 1 apply to local amendment of energy standards adopted by the California Energy Commission.
1.1.9 Effective date of this code. Only those standards approved by the California Building Standards Commission that are effective at the time an application for a building permit is submitted shall apply to the plans and specifications for, and to the construction performed under that permit. For the effective dates of the provisions contained in this code, see the History Note page of this code.
1.1.10 Availability of codes. At least one complete copy each of Titles 8, 19, 20, 24, and 25 with all revisions shall be maintained in the office of the building official responsible for the administration and enforcement of this code. Each state department concerned, and each city, county, or city and county shall have an up-to-date copy of the code available for public inspection. See Health and Safety Code, Section 18942(e)(1) and (2).
1.1.11 Format. This part fundamentally adopts the California Wildland-Urban Interface Code by reference on a chapter-by-chapter basis. When a specific chapter of the California Wildland-Urban Interface Code is not printed in the code and is marked “Reserved,” such a chapter of the California Wildland-Urban Interface Code is not adopted as a portion of this code. When a specific chapter of the Califor- nia Wildland-Urban Interface Code is marked “Not adopted by the State of California,” but appears in the code, it may be available for adoption by local ordinance.
CWUIC § 1.11. High relevance — show source text
- The California Code of Regulations (CCR), Title 19, Division 1 provisions that are found in the California Wildland-Urban Interface Code are a reprint from the current CCR, Title 19, Division 1 text for the code user’s convenience only. The scope, applicability and appeals procedures of CCR, Title 19, Division I remain the same. The state agency does not adopt sections identified by the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.
The California Code of Regulations (CCR), Title 14, Division 1.5 provisions that are found in the California Wildland-Urban Interface Code are not listed in the Matrix Adoption Tables as they are not within the State Fire Marshal’s authority to adopt. These provisions are a reprint from the current CCR, Title 14, Division 1.5 text for the code user’s convenience only and are identified in the body of the code by square brackets containing references to applicable Title 14 sections.
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A GENERAL REQUIREMENTS
The provisions contained in this appendix are not mandatory unless specifically referenced in the adopting ordinance.
User notes:
About this appendix: Appendix A, while not part of the code, can become part of the code when specifically included in the adopting ordinance. Its purpose is to provide fire protection measures supplemental to those found in Chapter 6 to reduce the threat of wildfire in a wildland-urban interface area and improve the capability for controlling such fires. This appendix includes detailed requirements for vegetation control; the code official’s authority to close wildland-interface areas in times of high fire danger; control of fires, fireworks usage and other sources of ignition; storage of hazardous materials and combustibles; bans on the dumping of waste materials and ashes and coals in wildland-urban interface areas; protection of pumps and water supplies; and limits on temporary uses within the wildland-urban interface area.
SECTION A101—GENERAL
A101.1 Scope. The provisions of this appendix establish general requirements applicable to new and existing properties located within wildland-urban interface areas .
A101.2 Objective. The objective of this appendix is to provide necessary fire protection measures to reduce the threat of wildfire in a wildland-urban interface area and improve the capability of controlling such fires.
SECTION A102—VEGETATION CONTROL
A102.1 General. Vegetation control shall comply with Sections A102.2 through A102.4.
A102.2 Clearance of brush or vegetative growth from roadways. The code official is authorized to require areas within 10 feet (3048 mm) on each side of portions of fire apparatus access roads and driveways to be cleared of nonfire-smart vegetation growth.
Exception: Single specimens of trees, ornamental vegetative fuels or cultivated ground cover, such as green grass, ivy, succulents or similar plants used as ground cover, provided they do not form a means of readily transmitting fire.
CWUIC § 603.4.1 High relevance — show source text
603.4.1 Shrubs. All new plantings of shrubs shall comply with the following: 1. Shrubs shall not exceed 6 feet (1829 mm) in height. 2. Groupings of shrubs are limited to a maximum aggregate diameter of 10 feet (3048 mm). 3. Shrub groupings shall be separated from other groupings a minimum of 15 feet (4572 mm). 4. Shrub groupings shall be separated from structures a minimum of 30 feet (9144 mm). 5. Where shrubs are located below or within a tree’s drip line, the lowest tree branch shall be a minimum of three times the height of the understory shrubs or 10 feet (3048 mm), whichever is greater.
603.4.2 Trees. Trees shall be managed as follows within the 30-foot zone (9144 mm) of a structure: 1. New trees shall be planted and maintained so that the tree’s drip line at maturity is a minimum of 10 feet (3048 mm) from any combustible structure. 2. The horizontal distance between crowns of new trees and crowns of adjacent trees shall not be less than 10 feet (3048 mm). 3. Existing trees shall be trimmed to provide a minimum separation of 10 feet (3048 mm) away from chimney and stovepipe outlets per California Code of Regulations, Title 14, Section 1299.03.
603.4.2.1 Nonfire-smart vegetation. New trees not classified as fire-smart vegetation, such as conifers, palms, pepper trees and eucalyptus species, shall be permitted provided the tree is planted and maintained in accordance with one of the following: 1. The tree is planted so that the tree’s drip line at maturity is a minimum of 30 feet (9144 mm) from an applicable building. 2. The tree is planted so that the tree’s drip line at maturity is a minimum of 10 feet (3048 mm) from any combustible struc- ture, and is well pruned and maintained so as not to form a means of rapidly transmitting fire from other nearby vegetation to the structure or from the structure to nearby vegetation or to interrupt the advance of embers toward a
structure.
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FIRE PROTECTION REQUIREMENTS
SECTION 604—MAINTENANCE OF DEFENSIBLE SPACE
604.1 General. Hazardous vegetation and fuels shall be managed to reduce the severity of potential exterior wildfire exposure to build- ings and to reduce the risk of fire spreading to buildings as required by applicable laws and regulations.
Defensible space shall be managed around all buildings and structures in State Responsibility Areas (SRA) as required in Public Resources Code 4291.
604.2 Application. Buildings and structures located in the following areas shall maintain the required hazardous vegetation and fuel management: 1. All unincorporated lands designated as a State Responsibility Area (SRA). 2. Land designated as a Very High Fire Hazard Severity Zone by a city or local agency. 3. Land designated in a city or local agency ordinance as a wildland-urban interface (WUI) area.
CWUIC § 1-2 High relevance — show source text
Population growth and the expanding urban development into traditionally nonurban areas have increasingly brought humans into contact with wildfires. According to the National Fire Protection Agency (NFPA), every year, wildfires burn across the United States and a growing number of people are living where wildfires are a real risk. In 2018 more than 58,000 fires burned nearly 9 million acres across the US. More than 25,000 structures were destroyed, including 18,137 residences and 229 commercial structures. California accounted for the highest number of structures lost in one state due to the number of significant fires, including the Mendocino Complex, Carr, Camp and Woolsey fires.
The IWUIC is a model code that is intended to be adopted and used supplemental to the adopted building and fire codes of a jurisdiction. The unrestricted use of property in wildland-urban interface areas is a potential threat to life and property from fire and resulting erosion. The IWUIC has as its objective the establishment of minimum special regulations for the safeguarding of life and
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property from the intrusion of fire from wildland fire exposures and fire exposures from adjacent structures and to prevent structure fires from spreading to wildland fuels, even in the absence of fire department intervention.
Safeguards to prevent the occurrence of fires and to provide adequate fire protection facilities to control the spread of fire in wildland-urban interface areas are provided in a tiered manner commensurate with the relative level of hazard present.
ARRANGEMENT AND FORMAT OF THE 2025 CWUIC
The format of the CWUIC allows each chapter to be devoted to a particular subject. The following table shows how the CWUIC is divided. The chapter synopses detail the scope and intent of the provisions of the CWUIC.
CHAPTER TOPICS Col2 CHAPTER SUBJECT 1-2 Administration and Definitions 3-4 Wildland-Urban Interface Area Designation and Requirements 5 Building Construction Regulations 6 Fire Protection Requirements 7 Referenced Standards Appendices A-I Adoptable and Informational Appendices Chapter 1 Scope and Administration.
Chapter 1 establishes the limits of applicability of the code and describes how the code is to be applied and enforced. The provisions of Chapter 1 establish the authority and duties of the code official appointed by the authority having jurisdiction and also establish the rights and privileges of the design professional, contractor and property owner.
Chapter 2 Definitions.
Chapter 2 is the repository of the definitions of terms used in the body of the code. The user of the code should be familiar with and consult this chapter because the definitions are essential to the correct interpretation of the code and because the user may not be aware that a term is defined.
Chapter 3 Wildland-Urban Interface Areas.
Chapter 3 provides for the fundamental aspect of applying the code—the legal declaration and establishment of wildland-urban interface areas within the adopting jurisdiction, mapping of the area, periodic review and updates.
Chapter 4 Wildland-Urban Interface Area Requirements.
The requirements of Chapter 4 apply to all occupancies in the wildland-urban interface and pertain to all of the following:
Fire service access to the property that is to be protected, including fire apparatus access roads and off-road driveways.
Premises identification.
CWUIC § 13108.5 High relevance — show source text
As an integral part of fire safety stan-_ dards, the State Fire Marshal has the authority to adopt regulations for roof coverings and openings into the attic areas of buildings specified in Section 13108.5 of the Health and Safety Code. The regulations apply to the placement of mobile homes as defined by National Fire Protection Association standards. These regulations do not apply where an application for a build- ing permit was filed prior to January 1, 1991, or to parcel or tentative maps or other developments approved prior to January 1, 1991, if the final map for the tentative map is approved within the time prescribed by the local ordinance. The regulations shall include all of the following: (1) Road standards for fire equipment access. (2) Standards for signs identifying streets, roads, and buildings. (3) Minimum private water supply reserves for emergency fire use. (4) Fuel breaks and greenbelts. (b) The board shall, on and after July 1, 2021, periodically update regulations for fuel breaks and greenbelts near communities to provide greater fire safety for the perimeters to all residential, commercial, and industrial building construction within state responsibility areas and lands classified and designated as very high fire hazard severity zones, as defined in subdivision (i) of Section 51177 of the Government Code, after July 1, 2021. These regulations shall include measures to preserve undeveloped
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APPENDIX H—REFERENCED CALIFORNIA DOCUMENTS
ridgelines to reduce fire risk and improve fire protection. The board shall, by regulation, define “ridgeline” for purposes of this subdivision.
(c) These regulations do not supersede local regulations which equal or exceed minimum regulations adopted by the state. (d) The board may enter into contracts with technical experts to meet the requirements of this section.
4290.1.
(a) On or before July 1, 2022, the board shall develop criteria for and maintain a “Fire Risk Reduction Community” list of local agen- cies located in a state responsibility area or a very high fire hazard severity zone, identified pursuant to Section 51178 of the Government Code, that meet best practices for local fire planning. (b) The board shall consider all of the following when developing the criteria for the list required under subdivision (a): (1) Compliance with the board’s regulations, including minimum fire safety standards. (2) Participation in the National Fire Protection Association’s “Firewise USA” or the National Wildfire Coordinating Group’s “Fire Adapted Communities” programs. (3) Adoption of the board’s recommendations to improve the safety element pursuant to subdivision (b) of Section 65302.5 of the Government Code.
(4) Recently developed or updated community wildfire protection plans. (c) The board shall post the “Fire Risk Reduction Community” list on its internet website.
4290.5.
CWUIC § 1-3 High relevance — show source text
Appendix G Voluntary Home-Hardening Recommendations.
Appendix G is an informational appendix that provides discussion of some elements of the proposed self-defense mechanisms and their role in enhancing the protection of exposed structures in the wildland-urban interface. The items provided in this appendix provide owners with suggestions for increasing the survivability of their structure. These items are not mandatory but can be considered by owners to increase the safety of structures.
Appendix H Referenced California Documents.
Appendix H contains portions of California statutes and regulations located in other documents. They are reprinted in Appendix H to aid the user in understanding the requirements applicable to wildland-urban interface areas and to provide a background for the provi- sions. Much of the text in the CWUIC is based on the requirements found in these other documents.
Appendix I Board of Appeals.
Appendix I contains the provisions for appeal and the establishment of a board of appeals. The provisions include the application for an appeal, the makeup of the board of appeals and the conduct of the appeal process.
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CONTENTS
CHAPTER 1 ADMINISTRATION. . . . . . . . . . . . . . . . . . . . . . .1-3
DIVISION I CALIFORNIA ADMINISTRATION
1.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
1.11 Office of the State Fire Marshal . . . . . . . . . . . . . . . . . . . 1-4
1.12 Board of Forestry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10
DIVISION II SCOPE AND ADMINISTRATION . . . . . . . . . . . . . 1-15
PART 1—GENERAL PROVISIONS. . . . . . . . . . . . . . . . . . . . . . . . . . 1-15
101 Scope and General Requirements. . . . . . . . . . . . . . 1-15
102 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-16
PART 2—ADMINISTRATION AND ENFORCEMENT . . . . . . . . . . . 1-17
103 Code Compliance Agency . . . . . . . . . . . . . . . . . . . . . 1-17
104 Duties and Powers of the Code Official . . . . . . . . . 1-17
105 Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-19
106 Construction Documents . . . . . . . . . . . . . . . . . . . . . 1-20
107 Temporary Uses, Equipment and Systems . . . . . . 1-21
CWUIC § 504.3 High relevance — show source text
504.3 Protection of enclosed eaves. The exposed underside of enclosed roof eaves and soffits shall be protected on the exposed underside by one or more of the following:
1. Noncombustible materials.
2. Ignition-resistant building materials. 3. Materials approved for not less than 1-hour fire-resistance-rated construction on the exterior side, as tested in accordance with ASTM E119 or UL 263.
4. 2-inch (51 mm) nominal dimension lumber . 5. 1-inch (25 mm) nominal fire-retardant-treated lumber or [3] / 4 -inch (19.1 mm) nominal fire-retardant-treated plywood, identified for exterior use and complying with Section 2303.2 of the California Building Code . 6. Boxed-in roof eave soffit assemblies with an underside that meets the performance criteria in Section 504.7.2 when tested in accordance with the test procedures set forth in ASTM E2957. 7. Boxed-in roof eave soffit assemblies with an underside that meets the performance criteria in accordance with the test proce- dures set forth in SFM Standard 12-7A-3.
Facias are required and shall be ignition-resistant building materials , fire-retardant-treated wood labeled for exterior use and complying with Section 2303.2 of the California Building Code, materials approved for not less than 1-hour fire-resistance-rated construction or 2-inch (51 mm) nominal dimension lumber.
504.3.1 Protection of open eaves. The exposed roof deck on the underside of unenclosed roof eaves shall consist of one or more of the following:
1. Noncombustible material.
2. Ignition-resistant building material. 3. Fire-retardant-treated wood labeled for exterior use and complying with Section 2303.2 of the California Building Code. 4. Materials approved for not less than 1-hour fire-resistance-rated construction on the exterior side, as tested in accordance with ASTM E119 or UL 263.
5. 2-inch (51 mm) nominal dimension lumber. 6. One layer of [5] / 8 -inch (16 mm) Type X gypsum sheathing applied behind an exterior covering on the underside of the roof deck.
7. The exterior portion of a 1-hour fire-resistance-rated exterior assembly, as tested in accordance with ASTM E119 or UL 263, applied to the underside of the roof deck designed for exterior fire exposure, including assemblies using the gypsum panel and sheathing products listed in the Gypsum Association Fire Resistance Design Manual.
2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE 5-5
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
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SPECIAL BUILDING CONSTRUCTION REGULATIONS
Facias, if provided, shall be of fire-retardant-treated wood labeled for exterior use and complying with Section 2303.2 of the Cali- fornia Building Code, ignition-resistant building materials, materials approved for not less than 1-hour fire-resistance-rated construction or 2-inch (51 mm) nominal dimension lumber.
CWUIC § 1.09.1 High relevance — show source text
_ (4) Designed to permit penetration through the use of fire department forcible entry tools and equipment unless other approved arrangements have been made with the fire authority having jurisdiction. (f) California Code of Regulations, Title 19, Division 1 regulations shall also apply to vehicles, ships and boats, or other mobile structures when fixed in a specific location and used for any occupancy within the scope of this section.
Note: Unless otherwise specified, Title 19 applies to all building occupancies, and related features and equipment throughout the
state.
[California Code of Regulations, Title 19, Division 1, §1.09.1] Order of Precedence.
In the event of any differences between the California Code of Regulations, Title 19, Division 1 regulations and the standard reference documents or standard fire prevention practices, the text of California Code of Regulations, Title 19, Division 1 regulations shall govern. Where a specific provision varies from a general provision, the specific provision shall apply.
SECTION 1.12—BOARD OF FORESTRY
1.12.1 BoF—Board of Forestry. The specific scope of application of the agency responsible for enforcement, the enforcement agency, and the specific authority to promulgate and enforce provisions applicable to wildland-urban interface areas, unless otherwise stated.
[California Code of Regulations, Title 14, Division 1.5, §1270.00] Title.
Subchapter 2 shall be known as the “State Minimum Fire Safe Regulations,” and shall constitute the minimum Wildfire protection stan- dards of the California Board of Forestry and Fire Protection.
[California Code of Regulations, Title 14, Division 1.5, §1270.01] Definitions.
The following definitions are applicable to Subchapter 2. (a) Agriculture: Land used for agricultural purposes as defined in a Local Jurisdiction's zoning ordinances. (b) Board: California Board of Forestry and Fire Protection. (c) Building: Any Structure used or intended for supporting or sheltering any use or Occupancy, except those classified as Utility and Miscellaneous Group U. (d) CAL FIRE: California Department of Forestry and Fire Protection. (e) Dead-end Road: A Road that has only one point of vehicular ingress/egress, including cul-de-sacs and Roads that loop back on themselves.
1-10 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
ADMINISTRATION
(f) Defensible Space: The area within the perimeter of a parcel, Development, neighborhood or community where basic wildland fire protection practices and measures are implemented, providing the key point of defense from an approaching Wildfire or defense against encroaching Wildfires or escaping Structure fires. The perimeter as used in this regulation is the area encom- _passing the parcel or parcels proposed for construction and/or Development, excluding the physical Structure itself.
Frequently asked questions
Who adopts and enforces CWUIC provisions locally?
Local adoption is done by cities, counties, or special districts following the code’s amendment requirements (findings and filings under §1.1.8). Enforcement is performed by the State Fire Marshal in some state facilities and by local fire chiefs or fire protection districts in their jurisdictions, per the code’s administration and enforcement rules .
Where and to whom does the CWUIC apply?
The CWUIC applies to the construction, alteration, relocation, and demolition of buildings and related work statewide where the code is adopted; it specifically targets buildings and developments in State Responsibility Areas, LRAs designated as Very High Fire Hazard Severity Zones, and locally declared WUI areas (see §1.1.3 and the applicability rules in §402) .
How does the CWUIC interact with Title 14/19, the Fire Code, and PRC 4291?
The code reproduces relevant CCR Title 14 and Title 19 material for convenience and cross‑references the California Fire Code for items like fire‑flow and water supply. Statutory defensible‑space duties (PRC 4291) are incorporated by reference in the CWUIC’s maintenance provisions (e.g., §604.1) so jurisdictions and property owners must comply with both the code and applicable state statutes .
More in California Wildland-Urban Interface Code
- Administration and Definitions
- Board of Appeals, Administration & Enforcement (permits, code official duties, appeals process)
- Wildland‑Urban Interface Area Designation & Mapping
- Fire Service Access & Water Supply (fire apparatus roads, driveways, hydrants, draft sites, standby power)
- Wildland‑Urban Interface Area Requirements (access, water, premises identification, key boxes)
- Referenced Standards & Test Methods
- Special Building Construction Regulations (ignition‑resistant construction, roof/vent/assembly requirements)
- Appendices and Model Ordinances (vegetation plans, severity‑zone adoption, home‑hardening guidance)
- Fire Protection Requirements (fire protection plans, systems, safety element provisions)
- Referenced California Documents & Matrix (CCR/Title 14 & 19 cross‑references, statutory references)
- Vegetation Management & Defensible Space (vegetation plans, maintenance, fire‑smart characteristics)
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