CWUIC · California Wildland-Urban Interface Code
Where are definitions located and how do they affect interpretation?
For any CWUIC term, first check Chapter 2 (definitions). If the term isn’t defined there, the code tells you to use the meaning in the referenced California codes (per §201.3); a section’s express language overrides the chapter definitions (per §201.1).
Last reviewed: July 6, 2026
Definitions for the CWUIC live in Chapter 2; those definitions control how terms in the rest of the code are read, and if a term isn’t defined in the CWUIC you use the definition from the referenced California codes. (Short rule: look in Chapter 2 first; otherwise follow §201.3.)
What the code requires — 2-4 sentences
Unless a provision expressly says otherwise, words and terms used in the CWUIC take the meanings given in Chapter 2 of the code — i.e., the definitions chapter — for application and enforcement. This is stated in §201.1 (Scope). If a term is not defined in the CWUIC, the code directs the user to take the meaning assigned to that term in the California Building, Fire, Electrical, Mechanical or Plumbing Codes (and related California codes) per §201.3. Together these rules determine where you look first for a definition and where you go next if no local definition exists.
Requirements in detail
Where the definitions live (and what that means)
- Primary repository: Chapter 2 (Definitions) — the words and terms shown there are the default meanings for the entire CWUIC (see §201.1).
- If a term is not present in Chapter 2, the CWUIC tells you to consult the specified California codes (CBC, CFC, CEC, CMC, CPC, etc.) — see §201.3.
How word-form rules affect reading
- The code’s general interpretive conventions (gender, tense, number) are stated at the section level and apply when reading defined or undefined words; see §201.2 for interchangeability rules (present/future, gender, singular/plural).
Order of precedence (decision-relevant)
| Decision question | What to do / value | Code Reference |
|---|---|---|
| Where do I look first for a defined term? | Chapter 2 (Definitions) | §201.1 |
| If the term is not in CWUIC, what controls? | Use the meaning in the California Building Code, California Fire Code, California Electrical Code, California Mechanical Code or California Plumbing Code (as applicable) | §201.3 |
| If still not defined anywhere cited by the code? | Use the ordinarily accepted meaning (context applies) — see Section 201 (terms not defined) | §201.4 |
| Does word form (singular/plural, gender, tense) change meaning? | Apply interchangeability rules (present includes future, masculine includes feminine/neuter, singular includes plural and vice versa) | §201.2 |
Practical interpretation rules to apply
- Always check Chapter 2 definitions before assuming a common/dictionary meaning (§201.1).
- If Chapter 2 does not define the term, apply the cross-reference rule in §201.3 and read the term as defined in the listed California codes.
- If a specific section of the CWUIC “expressly states” a different meaning for a term, that express statement overrides the Chapter 2 meaning for that section (see the “unless otherwise expressly stated” language in §201.1).
Exceptions & special cases
- Express local definition in a specific section: where the code text “expressly states” a definition or special meaning for a term, that local meaning governs for that provision (per §201.1).
- Terms that appear in the CWUIC but are bracketed or reproduced from CCR Title 14 or Title 19 may carry the original Title 14/19 cross-references — treat those as indicated in the code text (matrix and editorial notes). See Chapter 2 notes and the adoption matrix for cross-references.
- If a term is defined differently in two California codes the CWUIC points you to (for example CBC vs CFC), use the definition from the code identified by §201.3 and the specific context (which code the provision cross-references). If ambiguity remains, pursue code official interpretation or appeal procedures (see §112 for appeals).
Common mistakes
- Assuming “plain English” instead of checking Chapter 2: many users miss a CWUIC definition that changes how a requirement applies. Always verify Chapter 2 first (§201.1).
- Ignoring cross-code definitions: if CWUIC lacks a definition, failing to consult the California codes named in §201.3 leads to incorrect interpretation.
- Overlooking interchangeability rules (gender/number/tense) in §201.2 when applying a definition across multiple clauses.
- Treating editorial notes or bracketed Title 14/19 text as nonbinding: bracketed or reprinted provisions are included for convenience but their source and applicability are shown in the code—check the matrix/adoption notes (see Chapter 2 and Appendix H).
Worked example — deciding which definition controls (step-by-step with numbers)
Scenario: You are reviewing plans that call a 12 ft × 16 ft (192 ft²) covered platform a “porch.” You must decide whether WUI construction rules for “structures” apply.
- Step 1 — Look in CWUIC Chapter 2 (Section 202). The code tells users that words and terms have the meanings shown in Chapter 2 unless otherwise stated (§201.1). Check §202 (Chapter 2 definitions) for “porch,” “structure,” or “accessory structure.”
- Step 2 — If Chapter 2 does not define “porch” or is ambiguous, follow §201.3: consult the California Building Code or California Fire Code definitions referenced by the CWUIC to see how those codes treat small attached/detached platforms. If the CBC defines “porch” as a type of structure or “unenclosed accessory structure,” that CBC meaning controls for CWUIC application.
- Step 3 — If neither CWUIC nor the referenced California codes define the term, apply the ordinarily accepted meaning consistent with context per the code’s general rules (Section 201 guidance on terms not defined). If the accepted meaning would classify the 192 ft² platform as an accessory structure, then WUI-building construction provisions that apply to accessory structures would be the next items to check.
If the local enforcing agency has an express, local definition for “porch” in a CWUIC section or local amendment, that local definition governs despite Steps 1–3 (remember the “unless otherwise expressly stated” language in §201.1).
Related provisions
- §201 — General rules for definitions and terms in Chapter 2.
- §201.1 — Scope: definitions in this chapter apply unless otherwise expressly stated.
- §201.2 — Interchangeability rules (tense, gender, number).
- §201.3 — Where terms not defined in CWUIC are to be taken from other California codes (CBC, CFC, CEC, CMC, CPC).
- §202 — The definitions chapter (primary location of defined terms).
- §112 — Means of appeals (if you need an official interpretation of a definition).
Code references
Grounded in the retrieved California Wildland-Urban Interface Code — click a citation to read the verbatim passage:
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 § 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 § 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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2 DEFINITIONS
User notes:
About this chapter: Codes, by their very nature, are technical documents. Every word, term and punctuation mark can add to or change the meaning of a technical requirement. It is necessary to maintain a consensus on the specific meaning of each term contained in the code. Chapter 2 performs this function by stating clearly what specific terms mean for the purpose of the code.
SECTION 201—GENERAL
201.1 Scope. Unless otherwise expressly stated, the following words and terms shall, for the purposes of this code, have the meanings shown in this chapter.
201.2 Interchangeability. Words stated in the present tense include the future; words stated in the masculine gender include the feminine and neuter; and the singular number includes the plural and the plural the singular.
201.3 Terms defined in other codes. Where terms are not defined in this code and are defined in the California Building Code, Cali- fornia Existing Building Code, California Fire Code, California Electrical Code, California Mechanical Code or California Plumbing Code, such terms shall have the meanings ascribed to them as in those codes.
201.4 Terms not defined. Where terms are not defined through the methods authorized by this section, such terms shall have their ordinarily accepted meanings such as the context implies.
SECTION 202—DEFINITIONS
ACCESSORY STRUCTURE. A building or structure used to shelter or support any material, equipment, chattel or occupancy other than a habitable building.
AGRICULTURE (applicable to CCR, Title 14 provisions only). Land used for agricultural purposes as defined in a Local Jurisdiction's zoning ordinances. [CCR Title 14 §1270.01(a)]
APPLICABLE BUILDING. A building that has residential, commercial, educational, institutional or similar occupancy type use.
[A] APPROVED. Acceptable to the code official.
[A] APPROVED AGENCY. An established and recognized organization that is regularly engaged in conducting tests, furnishing inspection services or furnishing product evaluation or certification where such organization has been approved by the code official.
[A] BUILDING. Any structure intended for supporting or sheltering any occupancy.
BUILDING (applicable to CCR, Title 14 provisions only). Any Structure used or intended for supporting or sheltering any use or Occupancy, except those classified as Utility and Miscellaneous Group U. [CCR Title 14 §1270.01(c)]
CWUIC § 1-21 Medium relevance — show source text
107 Temporary Uses, Equipment and Systems . . . . . . 1-21
108 Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-21
109 Inspection and Enforcement . . . . . . . . . . . . . . . . . . 1-22
110 Certificate of Completion . . . . . . . . . . . . . . . . . . . . . 1-24
111 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24
112 Means of Appeals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24
113 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25
CHAPTER 2 DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
201 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
CHAPTER 3 WILDLAND-URBAN INTERFACE AREAS . . . . 3-3
301 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-3
302 Wildland-Urban Interface Area Designations . . . . . .3-3
CHAPTER 4 WILDLAND-URBAN INTERFACE AREA
REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . 4-3
401 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3
402 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3
403 Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3
404 Water Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-7
CHAPTER 5 SPECIAL BUILDING CONSTRUCTION
REGULATIONS . . . . . . . . . . . . . . . . . . . . . . . . 5-3
501 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-3
CWUIC § 1-4 Medium relevance — show source text
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
108 Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-21
109 Inspection and Enforcement . . . . . . . . . . . . . . . . . . 1-22
110 Certificate of Completion . . . . . . . . . . . . . . . . . . . . . 1-24
111 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24
112 Means of Appeals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24
113 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25
CHAPTER 2 DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
201 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
CHAPTER 3 WILDLAND-URBAN INTERFACE AREAS . . . . 3-3
CWUIC § 201.1 Medium relevance — show source text
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| |201|General|Y||||||||| |201.1|Scope|Y||||||||| |201.2|Interchangeability|Y||||||||| |201.3|Terms defined in
other codes|Y||201.3||||||| |201.4|Terms not defined|Y||||||||| |202|Definitions|Y||||||||| ||Accessory structure|Y||||||||| ||Agriculture (T14)|Y||||1270.01(1)||||| ||Applicable building|Y||702A||||||| ||Approved|Y||||||||| ||Approved agency|Y||||||||| ||Building|Y||||1270.01(c)||||| ||Building (T14)|Y||||||||| ||Building official|Y||||||||| ||Certificate of
completion|Y||||||||| ||Code official|Y||||||||| ||Critical fire weather|Y||||||||| ||Dead-end road (T14)|Y||||1270.01(e)||||| ||Defensible space (T14)|Y||||||||| ||Driveway (T14)|Y||||||||| ||Dwelling|Y||702A||1270.01(i)||||| ||Exterior wall assembly|Y||702A||||||| ||Exterior wall covering|Y||702A||||||| ||Fire chief|Y||||||||| ||Fire code official|Y|||202|||||| ||Fire flow calculation
area|Y||||||||| ||Fire hazard severity
zones|Y||702A|4902.1|||2201||| ||Fire protection plan|Y||702A|4902.1|||||| ||Fire weather|Y||||||||| ||Fire-resistance-rated
construction|Y||||||||| ||Fire-smart vegetation|Y|||4902.1|1271.01||||| ||Flame spread index|Y||||||||| ||Fuel|Y||||||||4291(a)(1)(A)| ||Fuel break_(T14)|Y||||1270.01(n)||||| ||Fuel modification|Y||||||||| ||Fuel mosaic|Y||||||||| ||Fuel-loading|Y||||||||| ||Green belt(T14)|Y||||1270.01(o)||||| ||Greenways (T14)|Y||||1270.01(p)||||| ||Hammerhead/T (T14)|Y||||1270.01(q)||||| ||Hazardous land use
(T14)_|Y||||1270.01(r)||||| ||Hazardous materials|Y||||||||| ||Heavy timber
construction|Y||||||||| ||Ignition-resistant
building material|Y||||||||| ||Local responsibility
area (LRA)|Y||702A|4902.1|||||| ||Log wall construction|Y|||||||||2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE APPENDIX H-25
CWUIC § 104.6 Medium relevance — show source text
3|||X||||||||||||||||||||| |104.6|||X||||||||||||||||||||| |104.8|||X||||||||||||||||||||| |104.8.1|||X||||||||||||||||||||| |105.1|||X||||||||||||||||||||| |105.2|||X||||||||||||||||||||| |105.3|||X||||||||||||||||||||| |105.4|||X||||||||||||||||||||| |105.8|||X||||||||||||||||||||| |105.10|||X||||||||||||||||||||| |106.1 – 106.5|||X||||||||||||||||||||| |106.8|||X||||||||||||||||||||| |106.10|||X||||||||||||||||||||| |107|||X||||||||||||||||||||| |109.1 – 109.1.2.3|||X||||||||||||||||||||| |109.3.7.1|||X||||||||||||||||||||| |109.3.7.2|||X||||||||||||||||||||| |110 – 111|||X||||||||||||||||||||| |113|||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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1 ADMINISTRATION
DIVISION I
CALIFORNIA ADMINISTRATION
SECTION 1.1—GENERAL
1.1.1 Title. These regulations shall be known as the California Wildland-Urban Interface Code, may be cited as such, and will be referred to herein as “this code.” The California Wildland-Urban Interface Code is Part 7 of thirteen parts of the official compilation and publica- tion of the adoptions, amendment, and repeal of building regulations to the California Code of Regulations, Title 24, also referred to as the California Building Standards Code. This part incorporates by adoption of the 2024 International Wildland-Urban Interface Code of the International Code Council (ICC) with necessary California amendments.
_**1.1.2 Purpose.
CWUIC § 2-5 Medium relevance — show source text
WILDFIRE. An uncontrolled fire spreading through vegetative fuels that threatens to destroy life, property or resources as defined in Public Resources Code Sections 4103 and 4104.
WILDFIRE EXPOSURE. One or a combination of radiant heat, convective heat, direct flame contact and burning embers being projected by vegetation fire to a structure and its immediate environment.
WILDLAND. An area in which development is essentially nonexistent, except for roads, railroads, power lines and similar facilities.
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DEFINITIONS
WILDLAND-URBAN INTERFACE AREA. A geographical area identified by the state as a “Fire Hazard Severity Zone” in accordance with the Public Resources Code Sections 4201 through 4204 and Government Code Sections 51175 through 51189, and other areas designated by the enforcing agency to be at a significant risk from wildfires.
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CALIFORNIA WILDLAND-URBAN INTERFACE CODE – MATRIX ADOPTION TABLE
CHAPTER 3 – WILDLAND-URBAN INTERFACE AREAS
(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-
CGSFM Col5 HCD Col7 Col8 DSA Col10 OSHPD Col12 Col13 Col14 Col15 Col16 BSCC DPH AGR DWR CEC CA SL SLC Adopting Agency BSC BSC-
CGT-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 CWUIC § 1.11. Medium relevance — show source text
Wall Assembly_|||X||||||||||||||||||||| |Exterior Wall Covering|||X||||||||||||||||||||| |Fire Code Official|||X||||||||||||||||||||| |Fire Hazard Severity Zones|||X||||||||||||||||||||| |Fire Protection Plan|||X||||||||||||||||||||| |Fire-Smart Vegetation|||X||||||||||||||||||||| |Flame Spread Index|||X||||||||||||||||||||| |Fuel|||X||||||||||||||||||||| |Fuel Modification|||X||||||||||||||||||||| |Local Responsibility Area (LRA)|||X||||||||||||||||||||| |Rafter Tail|||X||||||||||||||||||||| |Roof Eave|||X||||||||||||||||||||| |Roof Eave Soffit|||X||||||||||||||||||||| |State Responsibility Area (SRA)|||X||||||||||||||||||||| |Structure|||X||||||||||||||||||||| |Wildfire|||X||||||||||||||||||||| |Wildfire Exposure|||X||||||||||||||||||||| |Wildland-Urban Interface Area|||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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2 DEFINITIONS
User notes:
About this chapter: Codes, by their very nature, are technical documents. Every word, term and punctuation mark can add to or change the meaning of a technical requirement. It is necessary to maintain a consensus on the specific meaning of each term contained in the code. Chapter 2 performs this function by stating clearly what specific terms mean for the purpose of the code.
SECTION 201—GENERAL
201.1 Scope. Unless otherwise expressly stated, the following words and terms shall, for the purposes of this code, have the meanings shown in this chapter.
201.2 Interchangeability. Words stated in the present tense include the future; words stated in the masculine gender include the feminine and neuter; and the singular number includes the plural and the plural the singular.
CWUIC § 112.1 Medium relevance — show source text
The code official shall notify the serving utility and, where possible, the owner or the owner’s authorized agent and the occupant of the building, structure or service system of the decision to disconnect prior to taking such action. If not notified prior to disconnection, the owner, the owner’s authorized agent or the occupant of the building, structure or service system shall be notified in writing as soon as practical thereafter.
SECTION 112—MEANS OF APPEALS
[A] 112.1 General. In order to hear and decide appeals of orders, decisions or determinations made by the code official relative to the application and interpretation of this code, there shall be and is hereby created a board of appeals. The board of appeals shall be appointed by the applicable governing authority and shall hold office at its pleasure. The board shall adopt rules of procedure for conducting its business and shall render all decisions and findings in writing to the appellant, with a duplicate copy to the code official.
[A] 112.2 Limitations on authority. An application for appeal shall be based on a claim that the true intent of this code or the rules legally adopted thereunder have been incorrectly interpreted, the provisions of this code do not fully apply or an equivalent or better form of construction is proposed. The board shall not have authority to waive requirements of this code.
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ADMINISTRATION
[A] 112.3 Qualifications. The board of appeals shall consist of members who are qualified by experience and training on matters pertaining to the provisions of this code and are not employees of the jurisdiction.
[A] 112.4 Administration. The code official shall take action without delay in accordance with the decision of the board.
SECTION 113—STOP WORK ORDER
[A] 113.1 Authority. Where the code official finds any work regulated by this code being performed in a manner contrary to the provisions of this code or in a dangerous or unsafe manner, the code official is authorized to issue a stop work order.
[A] 113.2 Issuance. The stop work order shall be in writing and shall be given to the owner of the property, the owner’s authorized agent or the person performing the work. Upon issuance of a stop work order, the cited work shall immediately cease. The stop work order shall state the reason for the order and the conditions under which the cited work is authorized to resume.
[A] 113.3 Emergencies. Where an emergency exists, the code official shall not be required to give a written notice prior to stopping the work.
[A] 113.4 Failure to comply. Any person who shall continue any work after having been served with a stop work order, except such work as that person is directed to perform to remove a violation or unsafe condition, shall be subject to fines established by the authority having jurisdiction.
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CALIFORNIA WILDLAND-URBAN INTERFACE CODE – MATRIX ADOPTION TABLE
CHAPTER 2 – DEFINITIONS
CWUIC § 501.3 Medium relevance — show source text
501.3, 504.3, 504.3.1, 504.5, 504.7, 504.7.1
E136— 2024a : Standard Test Method for Assessing Combustibility of Materials Using a Vertical Tube Furnace at 750 Degrees C
501.4.1
E1354— 2023 : Standard Test Method for Heat and Visible Smoke Release Rates for Materials and Products Using an Oxygen Consumption Calorimeter
503.2.4.3.2, 503.2.4.3.3
E2632—2020: Standard Test Method for Evaluating the Under-Deck Fire Test Response of Deck Materials
504.7.3.2, 504.7.3.3, 504.7.3.3.1, 504.7.3.4
E2652—2022: Standard Test Method for Assessing Combustibility of Materials Using a Tube Furnace with a Cone-shaped Airflow Stabilizer, at 750°C
501.4.1
E2707—2022: Standard Test Method for Determining Fire Penetration of Exterior Wall Assemblies Using a Direct Flame Impingement Exposure
504.5, 504.9, 504.9.3
E2726/E2726M—2012a(2017): Standard Test Method for Evaluating the Fire Test Response of Deck Structures to Burning Brands
504.7.3.2, 504.7.3.3, 504.7.3.3.2
E2768—11(2018): Standard Test Method for Extended Duration Surface Burning Characteristics of Building Materials (30 min Tunnel Test)
503.2.4
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REFERENCED STANDARDS
E2886/E2886M—20: Standard Test Method for Evaluating the Ability of Exterior Vents to Resist the Entry of Embers and Direct Flame Impingement
504.10.1
E2957—2017 : Standard Test Method for Resistance to Wildfire Penetration of Eaves, Soffits and Other Projections
504.3, 504.7, 504.7.1, 504.7.2
G155—2021: Standard Practice for Operating Xenon Arc Lamp Apparatus for Exposure of Materials
504.9.2
ICC International Code Council, Inc., 200 Massachusetts Avenue, NW, Suite 250, Washington, DC 20001
CBC—2025: California Building Code
CWUIC § 504.7.3.3 Medium relevance — show source text
504.7.3.3 Performance requirements for Section 504.7.3.2, Item 1. Materials shall be tested in accordance with both ASTM E2632 and ASTM E2726 and comply with the conditions of acceptance in Sections 504.7.3.3.1 and 504.7.3.3.2. The material shall also be tested in accordance with ASTM E84 or UL 723 and comply with the performance requirements of Section 503.2.4.
504.7.3.3.1 Conditions of acceptance for ASTM E2632. The ASTM E2632 test shall be conducted on a minimum of three test specimens and meet the conditions of acceptance in Items 1 through 3. If any one of the three tests does not meet the conditions of acceptance, three additional tests shall be performed. All three additional tests must meet the conditions of acceptance. 1. Peak heat release rate of less than or equal to 25 kW/ft2 (269 kW/m2).
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SPECIAL BUILDING CONSTRUCTION REGULATIONS
2. Absence of sustained flaming or glowing combustion of any kind at the conclusion of the 40-minute observation period. 3. Absence of falling particles that are still burning when reaching the burner or floor.
504.7.3.3.2 Conditions of acceptance for ASTM E2726. The ASTM E2726 test shall be conducted, using a “Class A” size roof test brand, on a minimum of three test specimens and meet the conditions of acceptance in Items 1 and 2. If any one of the three tests does not meet the conditions of acceptance, three additional tests shall be performed. All three additional tests must meet the conditions of acceptance. 1. Absence of sustained flaming or glowing combustion of any kind at the conclusion of the 40-minute observation period. 2. Absence of falling particles that are still burning when reaching the burner or floor.
504.7.3.4 Performance requirements for Section 504.7.3.2, Item 7. The ASTM E2632 test shall be conducted on a minimum of three test specimens and the peak heat release rate shall be less than or equal to 25 kW/ft [2] (269 kW/m [2] ). If any one of the three tests does not meet the conditions of acceptance, three additional tests shall be run. All the additional tests shall meet the condi- tion of acceptance. If any one of the three tests does not meet the condition of acceptance, three additional tests shall be performed. All three additional tests must show a peak heat release rate shall be 25 kW/ft2 (269 kW/m2) or less.
504.8 Exterior glazing. Exterior windows, window walls and glazed doors, windows within exterior doors, and skylights shall be constructed of any of the following: 1. Multilayered glazed panels with at least one pane of tempered glass complying with Section 2406 of the California Building Code.
2. Glass block.
Frequently asked questions
How do I know whether to use a CWUIC definition or a CBC definition?
Start with Chapter 2 of the CWUIC: if the term is defined there, that definition controls. If not, §201.3 directs you to use the definition in the listed California codes (CBC, CFC, etc.).
What if a CWUIC section gives a different meaning than Chapter 2?
If a section “expressly states” a different meaning, that express statement governs for that section (see §201.1). Always follow the specific text where it exists.
My plan reviewer and I disagree on a term’s meaning. What can we do?
Use the appeal process — the code provides for a board of appeals to decide interpretations of the code (see §112 for appeals procedures).
Are dictionary meanings ever used?
Yes — when a term is not defined in the CWUIC and not defined in the California codes cited by §201.3, the code directs you to use the ordinarily accepted meaning that context implies. See the guidance in Section 201.
Do gender, tense, or number changes matter for definitions?
The code’s interchangeability rules mean they usually do not change the intended coverage: present tense includes future, masculine includes feminine and neuter, singular includes plural and vice versa (§201.2).
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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