CWUIC · California Wildland-Urban Interface Code
Who designates Fire Hazard Severity Zones and WUI areas?
The State Fire Marshal is the primary authority that maps and assigns **Fire Hazard Severity Zones** under **§ 302.1** of the CWUIC, using factors like fuel loading, slope, fire weather and winds; local code officials must review and recommend updates to **WUI areas** on a **5‑year** cycle and local adopters may use CWUIC Appendix D guidance for LRA adoption.
Last reviewed: July 6, 2026
What the code requires
The State Fire Marshal is the primary authority who designates and maps Fire Hazard Severity Zones for the State Responsibility Area and assigns zone ratings; the designation must follow the California statutes referenced in the CWUIC. See § 302.1 for the mapping requirement and its basis (fuel loading, slope, fire weather, winds, and other relevant factors) and see the related statutory procedure in PRC § 4203 and § 4204 as reprinted in the CWUIC.
The State Fire Marshal classifies lands into Fire Hazard Severity Zones based on factors such as fuel loading, slope, fire weather, and winds; local code officials must review and recommend WUI area updates on a regular basis.
Requirements in detail
Who does what (plain list)
- State Fire Marshal — Designates Fire Hazard Severity Zones and assigns ratings for lands in the state (SRA and LRA-related mapping per PRC/Gov Code) as required by § 302.1.
- Code official / Enforcing agency — Reevaluate and recommend modification of Wildland-Urban Interface (WUI) areas in accordance with § 302.1 and on the schedule in § 302.2.
- Local legislative bodies / counties — Receive notice of proposed State Fire Marshal regulations (statutory process requires transmission and a local public hearing before adoption per PRC § 4203).
What the classification must be based on
- Fuel loading
- Slope
- Fire weather
- 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 areas designated by the enforcing agency as at significant risk. All are explicitly listed in § 302.1.
Key timing and process values (decision table)
| Decision dimension | Typical values / action | Why it matters | Code Reference |
|---|---|---|---|
| Designating authority (SRA) | State Fire Marshal | Centralized mapping and ratings for State Responsibility Areas | § 302.1 |
| Designating authority (LRA) | State Fire Marshal maps per Gov Code; local ordinances can adopt LRA zones (model guidance in Appendix D) | Local application and adoption options for Local Responsibility Areas | § 302.1; Appendix D (model ordinance) |
| Classification basis | Fuel loading, slope, fire weather, winds, other factors | Drives which mitigation and construction rules apply | § 302.1 |
| Review interval (local recommendations) | 5‑year basis (or more often if legislative body decides) | Keeps maps current with changing hazard conditions | § 302.2 |
| Regulatory notice for State designation | 45 days prior transmission to county board + local public hearing (statutory PRC requirement) | Ensures local input before State rule adoption | PRC § 4203 (reprinted in CWUIC) |
What counts as a WUI area
- The CWUIC uses the mapping methodology in § 302.1 to identify Wildland-Urban Interface (WUI) areas; those areas are the basis for applying the code’s WUI construction and fire-protection provisions. The code links the mapping and classification process to the statutory framework (PRC & Government Code) used by the State Fire Marshal.
Exceptions & special cases
- The CWUIC reproduces some Title 14/Title 19 statutory text and notes that certain CCR provisions are outside the State Fire Marshal’s adoption authority; consult the appendices and the referenced statutes for where local adoption or state agency authority differs (see Appendix H and Appendix D guidance).
- Local jurisdictions may adopt or adapt model ordinances (Appendix D) to designate Fire Hazard Severity Zones in Local Responsibility Areas (LRA); the CWUIC’s Appendix D is informational guidance, not itself mandatory.
- Where the State Fire Marshal has adopted zone maps for State Responsibility Areas (SRA), those maps control for state-administered lands; local changes to those designations must follow the statutory petition/revision procedures in PRC § 4204 as reprinted in the CWUIC.
Common mistakes
- Treating local maps as authoritative for SRA parcels — SRA classifications come from the State Fire Marshal under § 302.1; local ordinances cannot override SRA designations without using the statutory revision process.
- Assuming the State Fire Marshal does not need to provide notice — PRC § 4203 (reprinted in the CWUIC) requires transmission to the county board at least 45 days before adoption and a public hearing in that period.
- Forgetting the 5‑year review requirement — local code officials should reevaluate WUI area boundaries and recommend modifications every 5 years (or sooner if needed) as stated in § 302.2.
Worked example — who controls a parcel’s zone?
Scenario: A homeowner’s parcel sits in an unincorporated area near a mixed-vegetation ridge.
- Determine land responsibility:
- If the parcel is in a State Responsibility Area (SRA), the State Fire Marshal is responsible for classifying it into a Fire Hazard Severity Zone and assigning the rating — per § 302.1.
- If the parcel is in a Local Responsibility Area (LRA), the State Fire Marshal still provides mapping methodology and may map zones, but the local jurisdiction can use the CWUIC’s Appendix D model ordinance process to adopt or refine LRA zone designations.
- Data considered for the rating:
- The mapping must use fuel loading, slope, fire weather, and winds among other factors (the same factors enumerated in § 302.1). For example, a steep (≥30°) slope with heavy brush and prevailing strong winds would point toward a higher severity rating.
- Timeline and change process:
- If the State Fire Marshal proposes a new designation or a rating change, they must transmit the proposed regulation to the county board at least 45 days before adoption and hold a local public hearing in that period (PRC § 4203 as reprinted).
- Local review:
- The local code official should be reevaluating and recommending WUI adjustments on a 5‑year cycle per § 302.2.
Related provisions
- § 302.2 — Review schedule and responsibilities for reevaluating WUI areas (5‑year basis)
- PRC § 4203 (reprinted in CWUIC Appendix H) — State Fire Marshal’s regulatory procedure and 45‑day notice/hearing requirement
- PRC § 4204 (reprinted in CWUIC Appendix H) — Periodic review, revision and petition process for zone designations
- Appendix D — Model Ordinance for Fire Hazard Severity Zone Adoption (guidance for LRA adoptions)
Code references
Grounded in the retrieved California Wildland-Urban Interface Code — click a citation to read the verbatim passage:
CWUIC § 302.1 High 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 High 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 § 11340.6 High relevance — show source text
4203.
(a) The State Fire Marshal shall, by regulation, designate fire hazard severity zones and assign to each zone a rating reflecting the degree of severity of fire hazard that is expected to prevail in the zone. (b) No designation of a zone and assignment of a rating shall be adopted by the State Fire Marshal until the proposed regulation has been transmitted to the board of supervisors of the county in which the zone is located at least 45 days before the adoption of the proposed regulation and a public hearing has been held in that county during that 45-day period. 4204. The State Fire Marshal shall periodically review zones designated and rated pursuant to this article and, as necessary, shall revise zones or their ratings or repeal the designation of zones. Any revision of a zone or its rating or any repeal of a zone shall conform to the requirements of Section 4203. In addition, the revision or repeal of a zone may be petitioned pursuant to Sections 11340.6 and 11340.7 of the Government Code.
4290.
(a) The board shall adopt regulations implementing minimum fire safety standards related to defensible space that are applicable to state responsibility area lands under the authority of the department, and to lands classified and designated as very high fire hazard severity zones, as defined in subdivision (i) of Section 51177 of the Government Code. These regulations apply to the perimeters and access to all residential, commercial, and industrial building construction within state responsibility areas approved after January 1, 1991, and within 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. The board may not adopt building standards, as defined in Section 18909 of the Health and Safety Code, under the authority of this section. 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
CWUIC § 11340.6 High relevance — show source text
The_ guidance document shall include, but not be limited to, regionally appropriate vegetation management suggestions that preserve and restore native species that are fire resistant or drought tolerant, or both, minimize erosion, minimize the spread of flammable nonnative grasses and weeds, minimize water consumption, and permit trees and shrubs near homes for shade, aesthetics, and habitat; and suggestions to minimize or eliminate the risk of flammability of nonvegetative sources of combus- tion such as woodpiles, propane tanks, decks, and outdoor lawn furniture. (2) On or before January 1, 2023, the State Board of Forestry and Fire Protection, in consultation with the Office of the State Fire Marshal, shall update the guidance document to include suggestions for creating an ember-resistant zone within five feet of a structure based on regulations promulgated by the State Board of Forestry and Fire Protection, in consultation with the Office of the State Fire Marshal, to consider the elimination of materials in the ember-resistant zone that would likely be ignited by embers.
(d) For purposes of this section, a structure for the purpose of an ember-resistant zone shall include any attached deck. This section does not limit the authority of the State Board of Forestry and Fire Protection or the Office of the State Fire Marshal to require the removal of fuel or vegetation on top of or underneath a deck pursuant to this section.
SECTION H103—CALIFORNIA PUBLIC RESOURCES CODE
Sections 4201–4204; 4290–4291.
4201. The purpose of this article is to provide for the classification of lands within state responsibility areas in accordance with the severity of fire hazard present for the purpose of identifying measures to be taken to retard the rate of spreading and to reduce the potential intensity of uncontrolled fires that threaten to destroy resources, life, or property. 4202. The State Fire Marshal shall classify lands within state responsibility areas into fire hazard severity zones. Each zone shall embrace relatively homogeneous lands and shall be based on fuel loading, slope, fire weather, and other relevant factors pres- ent, including areas where winds have been identified by the department as a major cause of wildfire spread.
4203.
(a) The State Fire Marshal shall, by regulation, designate fire hazard severity zones and assign to each zone a rating reflecting the degree of severity of fire hazard that is expected to prevail in the zone. (b) No designation of a zone and assignment of a rating shall be adopted by the State Fire Marshal until the proposed regulation has been transmitted to the board of supervisors of the county in which the zone is located at least 45 days before the adoption of the proposed regulation and a public hearing has been held in that county during that 45-day period. 4204. The State Fire Marshal shall periodically review zones designated and rated pursuant to this article and, as necessary, shall revise zones or their ratings or repeal the designation of zones. Any revision of a zone or its rating or any repeal of a zone shall conform to the requirements of Section 4203. In addition, the revision or repeal of a zone may be petitioned pursuant to Sections 11340.6 and 11340.7 of the Government Code.
4290.
(a) The board shall adopt regulations implementing minimum fire safety standards related to defensible space that are applicable to state responsibility area lands under the authority of the department, and to lands classified and designated as very high _fire hazard severity zones, as defined in subdivision (i) of Section 51177 of the Government Code.
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 § 403.2 High relevance — show source text
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Access Applicability 402 Driveways 403.2 Fire apparatus access roads 403.3 Grade 403.7
Individual structures 402.2 Marking of roads 402.3, 403.4 Restricted 403.1
Subdivisions 402.1 Accessory Buildings and Miscellaneous Structures
Defined 202
Detached 504.11 Exempt from permit 105.3 Additions or Alterations 101.5
Address Markers 402.3 Agriculture 202 Alternative Materials or Methods 104.2.2
Appeals 112 Appendices 101.2.1 Applicable Building 202 Applicability 102 Approved 202 Approved Agency 104.2.2.6.1, 202 Authority of Code Official 104
Building 202 Building Official 202
Certificate of Completion 111 Certificate of occupancy 111.2 Revocation 111.4
Temporary occupancy 111.3
Code Official 202 Code Official, Authority 104 Community Wildland-Urban Interface (WUI) Fire Hazard Evaluation Framework Appendix C Compliance Alternatives 105 Construction Documents 106
Amended 106.10
Examination of 106.9 Information on plans and specifications 106.2 Phased 106.12
Previous approval 106.11 Retention of 106.8 Site plan 106.3 Vegetation management plans 106.4 Control of Storage Appendix A, A105 Critical Fire Weather 202
Dead-end Road 202 Defensible Space 403, 601.3 Vegetation Plan 603 Definitions 202 Designation of Wildland-Urban Interface Area 302.1
Director 202 Driveway 202 Dumping Appendix A, A106 Dwelling 202
Exterior Covering 202
INDEX
Fees 109 Findings of Fact Appendix E Fire Chief 202 Fire Danger Rating System Appendix D Fire Flow Calculation Area Application 404.5 Defined 202 Fire Hazard Severity Zones 1.1.2, 202, 302.1, 302.2, Appendix D, Appendix H Fire Protection Plans 602
Fire Weather 202
Fire-Resistance-Rated Construction 501.3 Fire-Resistive Vegetation Appendix F Fire-Retardant-Treated Lumber or
Wood 503.2, 504.5, 504.7, 504.11 Flame Spread Index 202 Flashing 504.2.1, 504.5.1 Fuel Break 202, 609 Fuel Models Appendix D Fuel Modification 202
Fuel Modification Distance 603.2
Fuel Mosaic 202 Fuel-Loading 202
General Requirements Appendix A Green Belt 202
Greenways 202
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 § 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:
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 § 2025 Medium relevance — show source text
A104 Ignition Source Control . . . . . . . . . . . . . . APPENDIX A-5
A105 Control of Storage . . . . . . . . . . . . . . . . . . . APPENDIX A-5
A106 Dumping . . . . . . . . . . . . . . . . . . . . . . . . . . . APPENDIX A-6
A107 Protection of Pumps and Water Storage Facilities. . . . . . . . . . . . . . . . . APPENDIX A-6
A108 Land Use Limitations . . . . . . . . . . . . . . . . APPENDIX A-6
A109 Referenced Standards . . . . . . . . . . . . . . . APPENDIX A-7
APPENDIX B VEGETATION MANAGEMENT
PLAN . . . . . . . . . . . . . . . . . . . . . . APPENDIX B-3
B101 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . APPENDIX B-3
APPENDIX C COMMUNITY WILDLAND-URBAN
INTERFACE (WUI) FIRE HAZARD
EVALUATION FRAMEWORK . . . . APPENDIX C-3
C101 Community WUI Hazard Evaluation Framework . . . . . . . . . . . . . . . . . . . . . . APPENDIX C-3
APPENDIX D MODEL ORDINANCE FOR FIRE HAZARD
SEVERITY ZONE ADOPTION . . . . APPENDIX D-3
D101 Model Ordinance for Designation of Fire Hazard Severity Zones in Local Responsibility Areas (LRA) . . . . . . . . . . . . . . . . . . . . . . . APPENDIX D-3
APPENDIX E RESERVED . . . . . . . . . . . . . . . . . . APPENDIX E-1
APPENDIX F CHARACTERISTICS OF FIRE-SMART
VEGETATION . . . . . . . . . . . . . . . . APPENDIX F-3
F101 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . APPENDIX F-3
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CONTENTS
APPENDIX G VOLUNTARY HOME-HARDENING
RECOMMENDATIONS . . . . . . . . . . APPENDIX G-3
G101 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . APPENDIX G-3
APPENDIX H REFERENCED CALIFORNIA
DOCUMENTS . . . . . . . . . . . . . . . .APPENDIX H-3
CWUIC § 102.4 Medium relevance — show source text
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.
Appendix C contains a preliminary Community WUI Fire Hazard Evaluation Framework as a suggested methodology to begin to support communities at risk in the identification of their unique hazards and to provide common metrics for comparisons between communities. This preliminary framework includes information on community size, population and fuels; on notification and evacuation; and on the community infrastructure and firefighting response potential. Aspects of this framework may already be included in various community- level documents, such as Community Wildfire Protection Plans or evacuation plans. Development of a standard framework will (1) consolidate relevant WUI fire hazard and planning information in one place, and (2) allow for cross-community comparisons.
The evaluation required to implement this framework will support prefire hazard assessment and during-fire response operations. An increased understanding of fire evacuation, fire structural response and fire defensive action relationships is needed to assess the over- all community WUI fire hazard. The quantification of these relationships will enable communities to optimize the community-level response to WUI fire hazards in a more integrated approach and result in increased life safety and reduced losses.
Appendix D Model Ordinance for Fire Hazard Severity Zone Adoption.
Appendix D is an informational appendix that is a sample ordinance designed as guidance for a city, county, city and county, or fire district to establish and designate fire hazard severity zones within their jurisdiction.
Appendix E Reserved.
Appendix F Characteristics of Fire-Smart Vegetation.
Appendix F is an informational appendix provided for the convenience of the code user. It is simply a compilation of the eight characteristics of fire-smart vegetation that can be used effectively within wildland-urban interface areas to reduce the likelihood of fire spread through vegetation.
**App
CWUIC § 1-3 Medium relevance — show source text
Appendix C contains a preliminary Community WUI Fire Hazard Evaluation Framework as a suggested methodology to begin to support communities at risk in the identification of their unique hazards and to provide common metrics for comparisons between communities. This preliminary framework includes information on community size, population and fuels; on notification and evacuation; and on the community infrastructure and firefighting response potential. Aspects of this framework may already be included in various community- level documents, such as Community Wildfire Protection Plans or evacuation plans. Development of a standard framework will (1) consolidate relevant WUI fire hazard and planning information in one place, and (2) allow for cross-community comparisons.
The evaluation required to implement this framework will support prefire hazard assessment and during-fire response operations. An increased understanding of fire evacuation, fire structural response and fire defensive action relationships is needed to assess the over- all community WUI fire hazard. The quantification of these relationships will enable communities to optimize the community-level response to WUI fire hazards in a more integrated approach and result in increased life safety and reduced losses.
Appendix D Model Ordinance for Fire Hazard Severity Zone Adoption.
Appendix D is an informational appendix that is a sample ordinance designed as guidance for a city, county, city and county, or fire district to establish and designate fire hazard severity zones within their jurisdiction.
Appendix E Reserved.
Appendix F Characteristics of Fire-Smart Vegetation.
Appendix F is an informational appendix provided for the convenience of the code user. It is simply a compilation of the eight characteristics of fire-smart vegetation that can be used effectively within wildland-urban interface areas to reduce the likelihood of fire spread through vegetation.
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.
xii 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
CONTENTS
CHAPTER 1 ADMINISTRATION. . . . . . . . . . . . . . . . . . . . . . .1-3
DIVISION I CALIFORNIA ADMINISTRATION
1.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
CWUIC § 101.1 Medium relevance — show source text
PART 1—GENERAL PROVISIONS
SECTION 101—SCOPE AND GENERAL REQUIREMENTS
[A] 101.1 Title. These regulations shall be known as the California Wildland-Urban Interface Code of [ NAME OF JURISDICTION ], hereinafter referred to as “this code.”
[A] 101.2 Scope. This code applies to building materials, systems and/or assemblies used in the exterior design and construction of new buildings located within a wildland-urban interface (WUI) area and contains minimum requirements to mitigate conditions that might cause a fire originating in a structure to ignite vegetation in the wildland-urban interface (WUI) area, and conversely, a wildfire burning in vegetative fuels to transmit fire to buildings and threaten to destroy life, overwhelm fire suppression capabilities or result in large property losses.
[A] 101.2.1 Appendices. Provisions in the appendices shall not apply unless specifically adopted.
[A] 101.3 Purpose. The purpose of this code is to establish minimum regulations for the safeguarding of life and for property protection. Regulations in this code are intended to mitigate the risk to life and structures from intrusion of fire from wildland fire exposures and fire exposures from adjacent structures and to mitigate structure fires from spreading to wildland fuels. The extent of this regulation is intended to be tiered commensurate with the relative level of hazard present.
The unrestricted use of property in wildland-urban interface areas is a potential threat to life and property from fire and resulting erosion. 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 shall be in accordance with this code.
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:
Frequently asked questions
Who ultimately decides if my property is in a Fire Hazard Severity Zone?
The State Fire Marshal designates Fire Hazard Severity Zones under § 302.1 (and the PRC rules reprinted in the CWUIC). Local jurisdictions can adopt local ordinances for LRA areas using the CWUIC guidance (Appendix D).
How often are zones and WUI areas reviewed?
Local code officials should reevaluate and recommend modifications on a 5‑year basis or sooner per § 302.2; the State Fire Marshal periodically reviews SRA zones per PRC § 4204 (reprinted).
If I disagree with a designation, can it be changed?
Yes — statutory procedures allow revisions or petitions (see PRC § 4204 reprinted in the CWUIC). For local LRA designations consult the model ordinance guidance in Appendix D for local processes.
What factors should I expect the mapper to consider?
Expect fuel loading, slope, fire weather, and winds, plus any other relevant local risk factors — these are the explicit bases in § 302.1.
Do state maps override local maps?
For parcels in State Responsibility Areas (SRA), State-designated maps by the State Fire Marshal control; local maps and ordinances apply to LRA per local adoption rules and the CWUIC guidance.
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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