CWUIC · California Wildland-Urban Interface Code

Mapping criteria, zone types & classification

This hub explains how the CWUIC maps and classifies Fire Hazard Severity Zones—what factors are used, who does the mapping, and the required review cycle.

Last reviewed: July 6, 2026

Overview

This part of the California Wildland‑Urban Interface Code (CWUIC) establishes how wildland‑urban interface (WUI) areas and Fire Hazard Severity Zones are identified, mapped and classified so jurisdictions can apply the right mitigation and construction rules. The State Fire Marshal is charged with classifying lands into Fire Hazard Severity Zones and assigning zones that “embrace relatively homogeneous lands” based on factors such as fuel loading, slope, fire weather and wind exposure (§302.1) .

Mapping and classification are the legal foundation for all WUI requirements: they determine where Chapters 4–6 (area requirements, construction and fire‑protection provisions) apply and guide local adoption and ordinances. Chapter 3 describes designation and mapping procedures and the linkage to state statutes (PRC and Government Code) used to define State Responsibility Areas (SRA) and Local Responsibility Areas (LRA) .

Designations are not static — the code requires periodic reevaluation and recommends a 5‑year review cycle (or sooner as needed) so boundaries and zone assignments reflect changing fuels, development and risk (§302.2) .

In this section

Code references

Grounded in the retrieved California Wildland-Urban Interface Code — click a citation to read the verbatim passage:

  • CWUIC § 302.2 High relevance — show source text

    Each fire hazard severity zone shall_ embrace relatively homogeneous lands, and the classification shall be based on fuel loading, slope, fire weather and other relevant factors including areas where winds have been identified by the Office of the State Fire Marshal as a major cause of wildfire spread and other areas designated by the enforcing agency to be at a significant risk from wildfires.

    302.2 Review of wildland-urban interface areas. The code official shall reevaluate and recommend modification to the wildlandurban interface areas in accordance with Section 302.1 on a 5-year basis or more frequently as deemed necessary by the legislative body. The State Fire Marshal shall periodically review the areas in the state identified as fire hazard severity zones and, as necessary, shall make recommendations relative to fire hazard severity zones. This review shall coincide with the review of state responsibility area lands every five years and, when possible, fall within the time frames for the county’s general plan update.

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    CALIFORNIA WILDLAND-URBAN INTERFACE CODE – MATRIX ADOPTION TABLE

    CHAPTER 4 – WILDLAND-URBAN INTERFACE AREA REQUIREMENTS

    (Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

    Adopting Agency BSC BSC-
    CG
    SFM Col5 HCD Col7 Col8 DSA Col10 OSHPD Col12 Col13 Col14 Col15 Col16 BSCC DPH AGR DWR CEC CA SL SLC
    Adopting Agency BSC BSC-
    CG
    T-24 T-19* 1 2 1/AC AC SS 1 1R 2 3 4 5 5 5 5 5 5 5 5 5
    Adopt Entire Chapter
    Adopt Entire Chapter as
    amended (amended sections
    listed below)
    X
    Adopt only those sections that
    are listed below
    [California Code of Regulations,
    Title 19, Division 1]
    Chapter / Section
    402
    402.1.1 X
    402.1.2 X
    402.1.2.1 X
    402.2.1 X
    402.2.2 X
    402.
  • CWUIC § 302.1 Medium relevance — show source text

    SECTION 302—WILDLAND-URBAN INTERFACE AREA DESIGNATIONS

    302.1 Mapping . The State Fire Marshal shall classify lands into Fire Hazard Severity Zones in accordance with California Public Resources Code, Sections 4201 through 4204 for State Responsibility Areas and in accordance with Government Code, Sections 51175 through 51189 for Local Responsibility Areas. The State Fire Marshal shall designate areas in the state as fire hazard severity zones and assign each zone based on the severity of fire hazard that is expected to prevail in those areas. Each fire hazard severity zone shall embrace relatively homogeneous lands, and the classification shall be based on fuel loading, slope, fire weather and other relevant factors including areas where winds have been identified by the Office of the State Fire Marshal as a major cause of wildfire spread and other areas designated by the enforcing agency to be at a significant risk from wildfires.

    302.2 Review of wildland-urban interface areas. The code official shall reevaluate and recommend modification to the wildlandurban interface areas in accordance with Section 302.1 on a 5-year basis or more frequently as deemed necessary by the legislative body. The State Fire Marshal shall periodically review the areas in the state identified as fire hazard severity zones and, as necessary, shall make recommendations relative to fire hazard severity zones. This review shall coincide with the review of state responsibility area lands every five years and, when possible, fall within the time frames for the county’s general plan update.

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    CALIFORNIA WILDLAND-URBAN INTERFACE CODE – MATRIX ADOPTION TABLE

    CHAPTER 4 – WILDLAND-URBAN INTERFACE AREA REQUIREMENTS

    (Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

  • CWUIC § 1.5 Medium relevance — show source text

    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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    3 WILDLAND-URBAN INTERFACE AREAS

    User notes:

    About this chapter: Chapter 3 provides for the fundamental aspect of applying the code—the legal declaration and establishment of wildlandurban interface areas within the adopting jurisdiction, mapping of the area, periodic review and updates.

    SECTION 301—GENERAL

    301.1 Scope. The provisions of this chapter provide methodology to establish and record wildland-urban interface areas in accor- dance with California Public Resources Code (PRC) and California Government Code (GC).

    301.2 Purpose . The purpose of this chapter is to classify lands in the state in accordance with the level of fire hazard present for the purpose of identifying measures that will retard the rate of spread and reduce the potential intensity of uncontrolled fires that threaten to destroy resources, life or property, and to require that those measures be taken.

    SECTION 302—WILDLAND-URBAN INTERFACE AREA DESIGNATIONS

    302.1 Mapping . The State Fire Marshal shall classify lands into Fire Hazard Severity Zones in accordance with California Public Resources Code, Sections 4201 through 4204 for State Responsibility Areas and in accordance with Government Code, Sections 51175 through 51189 for Local Responsibility Areas. The State Fire Marshal shall designate areas in the state as fire hazard severity zones and assign each zone based on the severity of fire hazard that is expected to prevail in those areas. Each fire hazard severity zone shall embrace relatively homogeneous lands, and the classification shall be based on fuel loading, slope, fire weather and other relevant factors including areas where winds have been identified by the Office of the State Fire Marshal as a major cause of wildfire spread and other areas designated by the enforcing agency to be at a significant risk from wildfires.

    302.2 Review of wildland-urban interface areas. The code official shall reevaluate and recommend modification to the wildlandurban interface areas in accordance with Section 302.1 on a 5-year basis or more frequently as deemed necessary by the legislative body. The State Fire Marshal shall periodically review the areas in the state identified as fire hazard severity zones and, as necessary, shall make recommendations relative to fire hazard severity zones. This review shall coincide with the review of state responsibility area lands every five years and, when possible, fall within the time frames for the county’s general plan update.

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  • CWUIC § 302.1 Medium relevance — show source text

    2|Purpose|Y|||||||51176|4201| |302|Wildland-Urban
    Interface Area
    Designations|Y||||||||| |302.1|Mapping|Y|||4904.2||||51178|4202
    4203(a)
    4204| |302.2|Review of wildland-
    urban interface areas|Y|||||||51181|4204| |Chapter 4|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements| |401|General|Y||||||||| |401.1|Scope|Y||||||||| |401.2|Objective|Y||||1273.00||||| |401.3|General safety
    precautions|Y||||||||| |402|Applicability|Y|||||||||

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    APPENDIX H—REFERENCED CALIFORNIA DOCUMENTS

    2025 CWUIC—continued Col2 Adopted
    Yes/No
    IWUIC
    Section
    CBC
    Section
    CFC
    Section
    Title 14,
    Division 1.5
    Section
    Title 19,
    Division 1
    Section
    Gov Code
    Section
    PRC
    Section
    HSC
    Section
    Section Title Title Title Title Title Title Title Title Title Title
    Chapter 4 Wildland-urban interface area requirements Wildland-urban interface area requirements Wildland-urban interface area requirements Wildland-urban interface area requirements Wildland-urban interface area requirements Wildland-urban interface area requirements Wildland-urban interface area requirements Wildland-urban interface area requirements Wildland-urban interface area requirements Wildland-urban interface area requirements
    402.1 Subdivisions Y
    402.1.1 Access Y 503
    402.1.2 Water supply Y 507
    402.1.2.1 Parcel map approval Y 1275.01
    402.2 Individual structures Y 503
    507
    402.2.1 Access Y 503
    402.2.2 Water supply Y 507
    402.3 Existing conditions N 505.1
    403 Access Y 1273
    403.1 General Y 1273.00
    403.1.1 Section 403 definitions Y 1270.01(f)
    403.1.2 Width Y 1273.01(a)
    1273.
  • CWUIC § 1-2 Medium 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:

    1. Fire service access to the property that is to be protected, including fire apparatus access roads and off-road driveways.

    2. Premises identification.

  • CWUIC § 101.3.1 Medium relevance — show source text

    This code shall supplement the jurisdiction’s building and fire codes, if such codes have been adopted, to provide for special regulations to mitigate the fire- and life-safety hazards of the wildland-urban interface areas.

    101.3.1 Application. New buildings located in any Fire Hazard Severity Zone or Wildland-Urban Interface (WUI) Fire Area designated by the enforcing agency constructed after the application date shall comply with the provisions of this code. This shall include all new buildings with residential, commercial, educational, institutional or similar occupancy type use, which shall be referred to in this code as “applicable buildings,” as well as new buildings and structures accessory to those applicable buildings.

    Exceptions: 1. Group U occupancy accessory buildings of any size located at least 50 feet (15 240 mm) from an applicable building on the same lot.

    2. Group U occupancy agricultural buildings, as defined in Section 202 of the California Building Code of any size located at least 50 feet (15 240 mm) from an applicable building. 3. Group C occupancy special buildings conforming to the limitations specified in Section 450.4.1 of the California Building Code. 4. New accessory buildings and miscellaneous structures specified in Section 504.11 shall comply only with the requirements of that section.

    5. Additions to and remodels of buildings originally constructed prior to July 1, 2008.

    101.3.1.1 Application date and where required. New buildings for which an application for a building permit is submitted on or after July 1, 2008, located in any Fire Hazard Severity Zone or Wildland-Urban Interface Area shall comply with this code, including all of the following areas:

    All unincorporated lands designated by the State Board of Forestry and Fire Protection as State Responsibility Area (SRA) including:

    Moderate Fire Hazard Severity Zones.

    High Fire Hazard Severity Zones.

    Very High Fire Hazard Severity Zones.

    Land designated as a Very High Fire Hazard Severity Zone by cities and other local agencies.

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    ADMINISTRATION

    Land designated as a wildland-urban interface area by cities and other local agencies.

    Exceptions: 1. New buildings located in any Fire Hazard Severity Zone within a State Responsibility Area, for which an application for a building permit is submitted on or after January 1, 2008, shall comply with this code. 2. New buildings located in any Fire Hazard Severity Zone within a State Responsibility Area or any wildland-urban interface area designated by cities and other local agencies for which an application for a building permit is submit- ted on or after December 1, 2005, but prior to July 1, 2008, shall only comply with the following sections of this chapter: 2.1. Section 507 – Replacement or Repair of Roof Coverings.

    2.2. Section 504.10 – Vents.

    [A] 101.4 Retroactivity. The provisions of the code shall apply to conditions arising after the adoption thereof, conditions not legally in existence at the adoption of this code and conditions that, in the opinion of the code official, constitute a distinct hazard to life or property.

    Exception: Provisions of this code that specifically apply to existing conditions are retroactive.

  • CWUIC § 1270.01 Medium relevance — show source text

    1|||||| ||Strategic
    ridgeline (T14)|Y||||1270.01(dd)||||| ||Structure|Y|202|||1270.01(ee)||||| ||Subdivision|Y||||||||| ||Tree crown|Y||||||||| ||Undeveloped
    ridgeline (T14)|Y||||1270.01(ii)||||| ||Unenclosed acces-
    sory structure|Y||||||||| ||Vertical curve (T14)|Y||||1270.01(k)||||| ||Wildfire|Y||702A|4902.1|||||| ||Wildfire exposure|Y||702A|4902.1|||||| ||Wildland|Y||||||||| ||Wildland-urban inter-
    face area|Y||702A|4902.1|||||| |Chapter 3|Wildland-urban interface areas|Wildland-urban interface areas|Wildland-urban interface areas|Wildland-urban interface areas|Wildland-urban interface areas|Wildland-urban interface areas|Wildland-urban interface areas|Wildland-urban interface areas|Wildland-urban interface areas|Wildland-urban interface areas| |301|General|Y||||||||| |301.1|Scope|Y||||||||4201| |301.2|Purpose|Y|||||||51176|4201| |302|Wildland-Urban
    Interface Area
    Designations|Y||||||||| |302.1|Mapping|Y|||4904.2||||51178|4202
    4203(a)
    4204| |302.2|Review of wildland-
    urban interface areas|Y|||||||51181|4204| |Chapter 4|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements| |401|General|Y||||||||| |401.1|Scope|Y||||||||| |401.2|Objective|Y||||1273.00||||| |401.3|General safety
    precautions|Y||||||||| |402|Applicability|Y|||||||||

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    APPENDIX H—REFERENCED CALIFORNIA DOCUMENTS

    |2025 CWUIC—continued|Col2|Adopted
    Yes/No|IWUIC
    Section|CBC
    Section|CFC
    Section|Title 14,
    Division 1.5
    Section|Title 19,

  • CWUIC § 102.4 Medium 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 § 1-2 Medium 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:

    1. Fire service access to the property that is to be protected, including fire apparatus access roads and off-road driveways.

    2. Premises identification.

    3. Key boxes to provide ready access to properties secured by gated roadways or other impediments to rapid fire service access.

    4. Fire protection water supplies, including adequate water sources, pumper apparatus drafting sites, fire hydrant systems and system reliability.

    5. 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 § 65850.6 Medium relevance — show source text

    _ (2) Nothing in this subsection shall be construed to alter the extent to which utility infrastructure, including but not limited to wire- less telecommunications facilities, as defined in Government Code Section 65850.6, subdivision (d)(2), or Storage Group S or Utility and Miscellaneous Group U Structures, may be constructed on Undeveloped Ridgelines. (3) Local Jurisdictions may approve Buildings on Strategic Ridgelines where Development activities such as mass grading will significantly alter the topography that results in the elimination of Ridgeline fire risks. (d) The Local Jurisdiction may implement further specific requirements to preserve Undeveloped Ridgelines.

    [CCR T14 §1276.02]

    609.2 Fuel breaks. When applications meet any of the following criteria, the local jurisdiction shall determine the need and location for fuel breaks in consultation with the fire authority: (1) The permitting or approval of three or more new parcels, excluding lot line adjustments as specified in Government Code Section 66412(d); or (2) An application for a change of zoning increasing zoning intensity or density; or (3) An application for a change in use permit increasing use intensity or density.

    [CCR T14 §1276.03(a)]

    609.2.1 Exposures. Fuel breaks required by the local jurisdiction, in consultation with the fire authority, shall be located, designed and maintained in a condition that reduces the potential of damaging radiant and convective heat or ember exposure to access routes, buildings or infrastructure within the development. [CCR T14 §1276.03(b)]

    609.2.2 Fire department access. Fuel breaks shall have, at a minimum, one point of entry for firefighters and any fire apparatus. The specific number of entry points and entry requirements shall be determined by the local jurisdiction, in consultation with the fire authority. [CCR T14 §1276.03(c)]

    609.2.3 Location of fuel breaks. Fuel breaks may be required at locations such as, but not limited to: (1) Directly adjacent to defensible space as defined by Title 14 CCR Section 1299.02 to reduce radiant and convective heat expo- sure and ember impacts, or support firefighting tactics. (2) Directly adjacent to roads to manage radiant and convective heat exposure and ember impacts, increase evacuation safety, or support firefighting tactics. (3) Directly adjacent to a hazardous land use to limit the spread of fire from such uses, reduce radiant and convective heat exposure, or support firefighting tactics. (4) Strategically located along ridgelines, in greenbelts, or in other locations to reduce radiant and convective heat exposure and ember impacts, or support community level firefighting tactics.

    [CCR T14 §1276.03(d)]

    609.2.4 Timing. Fuel breaks shall be completed prior to the commencement of any permitted construction. [CCR T14 §1276.03(e)]

    609.2.5 Construction. Fuel breaks shall be constructed using the most ecologically and site appropriate treatment option, such as, but not limited to, prescribed burning, manual treatment, mechanical treatment, prescribed herbivory, and targeted ground applica- tion of herbicides. [CCR T14 §1276.03(f)]

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  • CWUIC § 301.1 Medium relevance — show source text
    Adopting Agency BSC BSC-
    CG
    SFM Col5 HCD Col7 Col8 DSA Col10 OSHPD Col12 Col13 Col14 Col15 Col16 BSCC DPH AGR DWR CEC CA SL SLC
    Adopting Agency BSC BSC-
    CG
    T-24 T-19* 1 2 1/AC AC SS 1 1R 2 3 4 5 5 5 5 5 5 5 5 5
    Adopt Entire Chapter
    Adopt Entire Chapter as
    amended (amended sections
    listed below)
    X
    Adopt only those sections that
    are listed below
    [California Code of Regulations,
    Title 19, Division 1]
    Chapter / Section
    301.1 X
    301.2 X
    302.1 X
    302.2 X
    • 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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    3 WILDLAND-URBAN INTERFACE AREAS

    User notes:

    About this chapter: Chapter 3 provides for the fundamental aspect of applying the code—the legal declaration and establishment of wildlandurban interface areas within the adopting jurisdiction, mapping of the area, periodic review and updates.

    SECTION 301—GENERAL

  • CWUIC § 1.5 Medium relevance — show source text

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    APPENDIX H—REFERENCED CALIFORNIA DOCUMENTS

    2025 CWUIC—continued Col2 Adopted
    Yes/No
    IWUIC
    Section
    CBC
    Section
    CFC
    Section
    Title 14,
    Division 1.5
    Section
    Title 19,
    Division 1
    Section
    Gov Code
    Section
    PRC
    Section
    HSC
    Section
    Section Title Title Title Title Title Title Title Title Title Title
    Chapter 2 Definitions Definitions Definitions Definitions Definitions Definitions Definitions Definitions Definitions Definitions
    Multilayered glazed
    panels
    Y
    Noncombustible roof
    covering
    Y
    Outbuilding (T14) Y 1299.02(c)
    Peer review Y
    Rafter tail Y 702A
    Registered design
    professional
    Y
    Residential unit (T14) Y 1270.01(w)
    Ridgeline
    (topography) (T14)
    Y 1270.01(x)
    Road (T14) Y 1270.01(y)
    Roof assembly Y
    Roof covering Y
    Roof covering system Y
    Roof deck Y
    Roof eave Y 702A
    Roof eave soffit Y 702A
    Slope Y
    State Responsibility
    Area (SRA)
    Y 702A 4902.1
    Strategic
    ridgeline (T14)
    Y 1270.01(dd)
    Structure Y 202 1270.01(ee)
    Subdivision Y
    Tree crown Y
    Undeveloped
    ridgeline (T14)
    Y 1270.01(ii)
    Unenclosed acces-
    sory structure
    Y
    Vertical curve (T14) Y 1270.01(k)
    Wildfire Y 702A 4902.1
    Wildfire exposure Y 702A 4902.1
    Wildland Y
    Wildland-urban inter-
    face area
    Y 702A 4902.1
    Chapter 3 Wildland-urban interface areas Wildland-urban interface areas Wildland-urban interface areas Wildland-urban interface areas Wildland-urban interface areas Wildland-urban interface areas Wildland-urban interface areas Wildland-urban interface areas Wildland-urban interface areas Wildland-urban interface areas
    301 General Y
    301.1 Scope Y 4201
    301.

Frequently asked questions

Who is responsible for mapping and designating Fire Hazard Severity Zones?

The State Fire Marshal is responsible for classifying and designating Fire Hazard Severity Zones (with reference to PRC and Government Code for SRA/LRA), and enforcing agencies or local jurisdictions may also designate WUI areas for their authority .

What criteria are used to classify zones?

Zones are based on relatively homogeneous lands and use factors including fuel loading, slope, prevailing fire weather, and wind conditions that affect wildfire spread; local risk factors may also be considered (§302.1) .

How often must maps and designations be reviewed or updated?

The code calls for reevaluation and recommended modification of wildland‑urban interface areas on a 5‑year basis or more frequently if the legislative body or code official deems it necessary (§302.2) .

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