Ember Entry, Vents & Wildland‑Specific Test Methods

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

• CWUIC § 12-7 High relevance — show source text

  504.8

  12-7A-3: Horizontal Projection Underside. A fire resistance test standard consisting of a 300 kW intensity direct flame exposure for a 10-minute duration

  504.3, 504.7, 504.7.1

  12-7A-4: Decking. A two-part test consisting of a heat release rate (Part A) deck assembly combustion test with an under deck exposure of 80 kW intensity direct flame for a 3-minute duration, and a (Part B) sustained deck assembly combustion test consisting of a deck upper surface burning ember exposure with a 12 mph wind for 40 minutes using a 2.2 lb (1kg) burning “Class A” size 12" × 12" × 2.25" (300 mm × 300 mm × 57 mm) roof test brand

  504.7.3.2

  12-7A-4A: Decking Alternate Method A. A heat release rate deck assembly combustion test with an under deck exposure of 80 kW intensity direct flame for a 3-minute duration

  504.7.3.2

  State Fire Marshal’s Guidelines for Fire Hydrant Markings Along State Highways and Freeways, May 1988

  404.8

  UL UL LLC, 333 Pfingsten Road, Northbrook, IL 60062-2096

  9—2009: Fire Tests of Window Assemblies—with Revisions through March 2020

  504.8

  10B—2008: Fire Tests of Door Assemblies—with Revisions through May 2020

  504.9

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  REFERENCED STANDARDS

  10C—2016: Positive Pressure Fire Tests of Door Assemblies—with Revisions through May 2021

  504.9

  94—2023: Tests for Flammability of Plastic Materials for Parts in Devices and Appliances

  504.9.2

  263—2011: Fire Tests of Building Construction and Materials—with Revisions through March 2022

  501.3, 504.3, 504.3.1, 504.5, 504.7, 504.7.1

  723—2018: Test for Surface Burning Characteristics of Building Materials

  202, 501.4.1, 503.2.4, 504.7.3.2, 504.7.3.3

  790— 2022 : Standard Test Methods for Fire Tests of Roof Coverings

  504.2, 504.2.1.2, 504.11.6

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  CALIFORNIA WILDLAND-URBAN INTERFACE CODE – MATRIX ADOPTION TABLE

  APPENDIX A – GENERAL REQUIREMENTS

• CWUIC § 504.9.3 Medium relevance — show source text

  Gaps between doors and door openings_ shall be controlled by one or more of the following methods: 1. Weather-stripping products constructed of materials that which comply with both of the following: 1.1. The tensile strength of the material shall be tested in accordance with ASTM D638 before and after exposure to ASTM G155 for a period of 2,000 hours, and the maximum allowable difference in tensile strength values between exposed and nonexposed samples shall not exceed 10 percent. 1.2. When tested to UL 94, the materials shall have a flammability rating of V-2 or better. 2. Door overlaps onto jambs and headers. 3. Garage door jambs and headers covered with metal flashing.

  504.9.3 Conditions of acceptance for ASTM E2707. The ASTM E2707 test shall be conducted 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 do 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 flame penetration through the wall assembly at any time. 2. Absence of evidence of glowing combustion on the interior surface of the assembly at the end of the 70-minute test.

  504.10 Vents. Where provided, ventilation openings for enclosed attics, gable ends, ridge ends, under eaves and cornices, enclosed eave soffit spaces, enclosed rafter spaces formed where ceilings are applied directly to the underside of roof rafters, underfloor venti

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  SPECIAL BUILDING CONSTRUCTION REGULATIONS

  lation, foundations and crawl spaces, or any other opening intended to permit ventilation, either in a horizontal or vertical surface, shall be in accordance with Section 504.10.1 or Section 504.10.2 to resist building ignition from the intrusion of burning embers and flame through the ventilation openings.

  504.10.1 Performance requirements. Ventilation openings shall be fully covered with Wildfire Flame and Ember Resistant vents approved and listed by the California State Fire Marshal, or WUI vents, tested in accordance with ASTM E2886, to demonstrate compliance with all the following requirements:

  1. There shall be no flaming ignition of the cotton material during the Ember Intrusion Test.
  2. There shall be no flaming ignition during the Integrity Test portion of the Flame Intrusion Test.
  3. The maximum temperature of the unexposed side of the vent shall not exceed 662°F (350°C).

  504.10.2 Off ridge and ridge vents. Vents that are installed on a sloped roof, such as dormer vents, shall comply with all of the following: 1. Vents shall be covered with a mesh where the dimensions of the mesh therein shall be a minimum of [1] / 16 inch (1.6 mm) and shall not exceed [1] / 8 inch (3.2 mm) in diameter.

  2. The vent and mesh material shall be noncombustible.

  3. The vent and mesh material shall be corrosion resistant.

• CWUIC § 504.10.1 Medium relevance — show source text

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  SPECIAL BUILDING CONSTRUCTION REGULATIONS

  lation, foundations and crawl spaces, or any other opening intended to permit ventilation, either in a horizontal or vertical surface, shall be in accordance with Section 504.10.1 or Section 504.10.2 to resist building ignition from the intrusion of burning embers and flame through the ventilation openings.

  504.10.1 Performance requirements. Ventilation openings shall be fully covered with Wildfire Flame and Ember Resistant vents approved and listed by the California State Fire Marshal, or WUI vents, tested in accordance with ASTM E2886, to demonstrate compliance with all the following requirements:

  1. There shall be no flaming ignition of the cotton material during the Ember Intrusion Test.
  2. There shall be no flaming ignition during the Integrity Test portion of the Flame Intrusion Test.
  3. The maximum temperature of the unexposed side of the vent shall not exceed 662°F (350°C).

  504.10.2 Off ridge and ridge vents. Vents that are installed on a sloped roof, such as dormer vents, shall comply with all of the following: 1. Vents shall be covered with a mesh where the dimensions of the mesh therein shall be a minimum of [1] / 16 inch (1.6 mm) and shall not exceed [1] / 8 inch (3.2 mm) in diameter.

  2. The vent and mesh material shall be noncombustible.

  3. The vent and mesh material shall be corrosion resistant.

  504.10.3 Vent locations. Gable-end and dormer vents shall be located not less than 10 feet (3048 mm) from lot lines. Underfloor ventilation openings shall be located as close to grade as practical.

  504.11 Accessory buildings and miscellaneous structures. Accessory buildings and miscellaneous structures that have the potential to pose a significant exterior fire exposure hazard during wildfires shall be constructed to conform to the ignition-resistance require- ments of this section.

  504.11.1 Applicability . Sections 504.11.2 through 504.11.6 apply to buildings accessory to an applicable building on the same lot, and attached or detached miscellaneous structures that require a building permit, including but not limited to trellises, arbors, patio covers, gazebos and similar structures.

  Exceptions: 1. Decks shall comply with the requirements of Section 504.7.3. 2. Awnings and canopies shall comply with the requirements of Section 3105 of the California Building Code.

  504.11.2 Miscellaneous structures and accessory buildings within 3 feet. Miscellaneous structures that require a permit, and accessory buildings of any size, when separated from an applicable building on the same lot by a distance of less than 3 feet (914 mm), shall be constructed of noncombustible materials or ignition-resistant building materials as described in Section 503.2.4.

• CWUIC § 504.9 Medium relevance — show source text

  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

  1.1.7.3.1, 1.11.2.1.2, 1.11.3.4, 1.11.6 – 1.11.10, 101.3.1, 102.8, 105.1, 105.3, 106.3, 202, 404.10.3, 501.1, 501.3, 503.1, 503.2.2, 503.2.3, 504.2.1.2, 504.3, 504.3.1, 504.5, 504.5.2, 504.6, 504.7, 504.7.3.2, 504.8, 504.11, 504.11.1

  CEBC—2025: California Existing Building Code

  1.11.3.4, 102.8, 201.3

  CFC—2025: California Fire Code

  1.11.3.4, 1.11.9, 1.11.10, 102.8, 105.1, 201.3, 202, 402.1.1, 402.1.2, 402.2.1, 402.2.2, 403.2.4, 404.2, 404.4, 404.5, 404.10.3, 606.1, 606.2

  CRC—2025: California Residential Code

  1.1.7.3.1, 102.8

  NFPA National Fire Protection Association, 1 Batterymarch Park, Quincy, MA 02169-7471

• CWUIC § 2.1.3 Medium relevance — show source text

  2.1.3|Content|N||||||||| |104.2.1.4|Tests|N||||||||| |104.2.2|Alternative
  materials, design and
  methods|Y||1.11.2.4
  1.11.2.5||||||| |104.2.2.1|Approval authority|N||||||||| |104.2.2.2|Application and
  disposition|N||1.11.2.4
  1.11.2.5||||||| |104.2.2.3|Compliance with
  code intent|N||||||||| |104.2.2.4|Equivalency criteria|N||||||||| |104.2.2.5|Tests|N||||||||| |104.2.2.6|Reports|N||||||||| |104.2.2.6.1|Evaluation reports|N||||||||| |104.2.2.6.2|Other reports|N||||||||| |104.2.2.7|Peer review|N||||||||| |104.2.3|Modifications|N||||||||| |104.3|Applications and
  permits|Y||||||||| |104.4|Right of entry|N||||||||| |104.4.1|Warrant|N||||||||| |104.5|Identification|N||||||||| |104.6|Notices and orders|Y||||||||| |104.7|Official records|N||||||||| |104.7.1|Approvals|N||||||||| |104.7.2|Inspections|N||||||||| |104.7.3|Code alternatives
  and modifications|N||||||||| |104.7.4|Tests|N||||||||| |104.7.5|Fees|N||||||||| |104.8|Liability|Y||||||||| |104.8.1|Legal defense|Y||||||||| |104.9|Approved materials
  and equipment|N||||||||| |104.9.1|Material and
  equipment reuse|N||||||||| |104.10|Other agencies|N||||||||| |105|Permits|Y||||||||| |105.1|General|Y||||||||| |105.2|Permits required|Y||||||||| |105.3|Work exempt from
  permit|Y||||||||| |105.4|Permit application|Y||||||||| |105.4.1|Preliminary
  inspection|N||||||||| |105.4.2|Time limitation of
  application|N||||||||| |105.5|Permit approval|N||||||||| |105.6|Permit issuance|N||||||||| |105.6.1|Refusal to issue a
  permit|N||||||||| |105.7|Validity of permit|N||||||||| |105.8|Expiration|Y||105.5.1||||||| |105.9|Retention of permits|N|||||||||

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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 § 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 § 909.21.1.1 Medium relevance — show source text

  909.21.1.1 Use of ventilation systems. Ventilation systems, other than hoistway supply air systems, are permitted to be used to exhaust air from adjacent spaces on the fire floor, two floors immediately below and one floor immediately above the fire floor to the building’s exterior where necessary to maintain positive pressure relationships as required in Section 909.21.1 during operation of the elevator shaft pressurization system.

  909.21.2 Rational analysis. A rational analysis complying with Section 909.4 shall be submitted with the construction documents.

  909.21.3 Ducts for system. Any duct system that is part of the pressurization system shall be protected with the same fire-resistance rating as required for the elevator shaft enclosure.

  909.21.4 Fan system. The fan system provided for the pressurization system shall be as required by Sections 909.21.4.1 through 909.21.4.4.

  909.21.4.1 Fire resistance. Where located within the building, the fan system that provides the pressurization shall be protected with the same fire-resistance rating required for the elevator shaft enclosure.

  909.21.4.2 Smoke detection. The fan system shall be equipped with a smoke detector that will automatically shut down the fan system when smoke is detected within the system.

  909.21.4.3 Separate systems. A separate fan system shall be used for each elevator hoistway.

  909.21.4.4 Fan capacity. The supply fan shall be either adjustable with a capacity of not less than 1,000 cubic feet per minute (0.4719 m [3] /s) per door, or that specified by a registered design professional to meet the requirements of a designed pressurization system.

  909.21.5 Standby power. The pressurization system shall be provided with standby power in accordance with Section 2702.

  909.21.6 Activation of pressurization system. The elevator pressurization system shall be activated upon activation of the elevator lobby smoke detectors.

  909.21.7 Testing. Testing for performance shall be required in accordance with Section 909.18.8. System acceptance shall be in accordance with Section 909.19.

  909.21.8 Marking and identification. Detection and control systems shall be marked in accordance with Section 909.14.

  909.21.9 Control diagrams. Control diagrams shall be provided in accordance with Section 909.15.

  909.21.10 Control panel. A control panel complying with Section 909.16 shall be provided.

  909.21.11 System response time. Hoistway pressurization systems shall comply with the requirements for smoke control system response time in Section 909.17.

  SECTION 910—SMOKE AND HEAT REMOVAL

  [F] 910.1 General. Where required by this code, smoke and heat vents or mechanical smoke removal systems shall conform to the requirements of this section.

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  FIRE PROTECTION AND LIFE SAFETY SYSTEMS

  [F] 910.2 Where required. Smoke and heat vents or a mechanical smoke removal system shall be installed as required by Sections 910.2.1 and 910.2.2.

• CWUIC § 1299.02 Medium relevance — show source text

  _ (b) Fuel Breaks required by the Local Jurisdiction, in consultation with the Fire Authority, shall be located, designed, and main- tained 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. (c) Fuel Breaks shall have, at a minimum, one point of entry for fire fighters 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. (d) Fuel Breaks may be required at locations such as, but not limited to: (1) Directly adjacent to defensible space as defined by 14 CCR § 1299.02 to reduce radiant and convective heat exposure, ember impacts, or support fire suppression tactics; (2) Directly adjacent to Roads to manage radiant and convective heat exposure or ember impacts, increase evacuation safety, or support fire suppression 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 fire suppression tactics; (4) Strategically located along Ridgelines, in Greenbelts, or other locations to reduce radiant and convective heat exposure, ember impacts, or support community level fire suppression tactics. (e) Fuel Breaks shall be completed prior to the commencement of any permitted construction. (f) 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 application of herbicides.

  (g) Where a Local Jurisdiction requires Fuel Breaks, maintenance mechanisms shall be established to ensure the fire behavior objectives and thresholds are maintained over time. (h) The mechanisms required shall be binding upon the property for which the Fuel Break is established, shall ensure adequate maintenance levels, and may include written legal agreements; permanent fees, taxes, or assessments; assessments through a homeowners' association; or other funding mechanisms.

  1276.04 Greenbelts, greenways, open spaces and parks. (a) Where a Greenbelt, Greenway, open space, park, landscaped or natural area, or portions thereof, is intended to serve as a Fuel Break, the space or relevant portion thereof shall conform with the requirements in § 1276.03 (Fuel Breaks).

  1276.05 Disposal of flammable vegetation and fuels.

  The disposal, including burning or removal to a site approved by the Local Jurisdiction, in consultation with the Fire Authority, of flam- mable vegetation and fuels caused by site construction, Road, and Driveway construction shall be in accordance with all applicable laws and regulations.

  H104.2 Subchapter 3 Fire Hazard.

  Article 3. Fire Hazard Reduction Around Buildings and Structures

  1299.01 Purpose. The intent of this regulation is to provide guidance for implementation of Public Resources Code Section 4291 to improve safety for fire fighters defending a home as well as increase the survivability of a “Building or Structure” as defined, that exists in grass, brush, and forest covered lands within the designated State Responsibility Area (SRA) of California.

• CWUIC § 2.1 Medium relevance — show source text

  This appendix is for informational purposes and is not intended for adoption.

  User notes:

  About this appendix: Appendix G is an information 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.

  SECTION G101—GENERAL

  G101.1 Identification of the problem. The California Wildland-Urban Interface Code establishes a set of minimum standards to reduce the loss of property from wildfire. The purpose of these standards is to prevent wildfire spreading from vegetation to a building. Many homes were built in the wildland-urban interface areas prior to the implementation of provisions found in this code. As a result, many homes are lacking in their ability to survive an approaching wildfire. Many of the features discussed in this appendix are designed as low- cost features to retrofit existing homes. Additionally, recommendations are provided beyond the minimum code requirements for those homeowners who desire to increase the survivability of their home. This appendix chapter provides a discussion of some possible self- defense features to enhance survivability and harden the structure against an approaching wildfire.

  G101.2 Structural survivability. The home-hardening features listed in Section G101.2.1 were developed as a best practices guide to assist homeowners in increasing the ignition resistance of their homes from wildfires. Some of these items are based on upgrading to more stringent building materials when that building component is due for replacement as part of its normal maintenance or lifespan, such as the roof covering.

  G101.2.1 Home-hardening features. If homes are not already provided with the suggested protection, the following items should be considered in hardening a home against wildfire. 1. When it is time to replace your roof, replace it with roof assembly classified as Class A when tested in accordance with ASTM E108 or UL 790.

  2. Block any spaces at the eaves between your roof covering and sheathing with noncombustible materials (bird stops). 3. Install a noncombustible rain gutter and downspouts. Install rain gutter covers to prevent the accumulation of leaves and debris in the gutters. 4. Cover your chimney and stovepipe outlets with a noncombustible, corrosion-resistant metal mesh screen (spark arrestor), with [3] / 8 -inch (9.5 mm) to [1] / 2 -inch (12.7 mm) openings. 5. Install ember- and flame-resistant vents. Choose products that have been approved and labeled as OSFM Wildland-Urban Interface (WUI) Products. A temporary solution is to cover the vent openings with a noncombustible and corrosion-resistant mesh with [1] / 16 -inch (1.6 mm) to [1] / 8 -inch (3.2 mm) openings. 6. Caulk and plug gaps greater than [1] / 8 inch (3.2 mm) around exposed rafters and blocking to prevent ember intrusion into the attic or other enclosed spaces. 7. _Inspect exterior siding for dry rot, gaps, cracks and warping.

• CWUIC § 2.1 Medium relevance — show source text

  G101.2.1 Home-hardening features. If homes are not already provided with the suggested protection, the following items should be considered in hardening a home against wildfire. 1. When it is time to replace your roof, replace it with roof assembly classified as Class A when tested in accordance with ASTM E108 or UL 790.

  2. Block any spaces at the eaves between your roof covering and sheathing with noncombustible materials (bird stops). 3. Install a noncombustible rain gutter and downspouts. Install rain gutter covers to prevent the accumulation of leaves and debris in the gutters. 4. Cover your chimney and stovepipe outlets with a noncombustible, corrosion-resistant metal mesh screen (spark arrestor), with [3] / 8 -inch (9.5 mm) to [1] / 2 -inch (12.7 mm) openings. 5. Install ember- and flame-resistant vents. Choose products that have been approved and labeled as OSFM Wildland-Urban Interface (WUI) Products. A temporary solution is to cover the vent openings with a noncombustible and corrosion-resistant mesh with [1] / 16 -inch (1.6 mm) to [1] / 8 -inch (3.2 mm) openings. 6. Caulk and plug gaps greater than [1] / 8 inch (3.2 mm) around exposed rafters and blocking to prevent ember intrusion into the attic or other enclosed spaces. 7. Inspect exterior siding for dry rot, gaps, cracks and warping. Caulk or plug gaps greater than [1] / 8 inch (3.2 mm) in siding and replace any damaged boards, including those with dry rot. 8. Install weather stripping to fill gaps greater than [1] / 8 inch (3.2 mm) between garage doors and door frames to prevent ember intrusion. The weather stripping must be compliant with UL Standard 10C. 9. When it’s time to replace your windows, replace them with multipaned windows that have at least one pane of tempered glass. Choose products that have been approved and labeled as OSFM Wildland-Urban Interface (WUI) Products. 10. When it’s time to replace your siding or deck, use noncombustible, ignition-resistant, or other OSFM-approved Wildland- Urban Interface (WUI) Products. 11. Cover openings to operable skylights with noncombustible metal mesh screen with openings in the screen not to exceed [1] / 8 inch (3.2 mm). 12. Install a minimum 6-inch metal flashing, applied vertically on the exterior of the wall at the deck-to-wall intersection to protect the combustible siding material. 13. _Enclose openings beneath decks or cantilevered construction with one of the materials required in Section 504.5.

• 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|||||||||

  APPENDIX H-26 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE

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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.

• California Wildland-Urban Interface Code Medium relevance — show source text

  
  2
  3|120
  123
  126|444
  498
  540|216
  247
  281|142
  145
  147|582
  652
  705|277
  321
  366|165
  168
  171|739
  825
  893|348
  407
  463| |15|1
  2
  3|125
  128
  131|511
  558
  597|229
  260
  292|153
  156
  159|658
  718
  760|297
  339
  382|184
  187
  190|824
  900
  960|375
  432
  486| |20|1
  2
  3|123
  126
  129|584
  625
  661|239
  270
  301|150
  153
  156|752
  805
  851|312
  354
  396|180
  184
  187|943
  1011
  1067|397
  452
  505| |30|1
  2
  3|119
  122
  125|680
  715
  746|255
  287
  317|145
  149
  152|883
  928
  968|337
  378
  418|175
  179
  182|1115
  1171
  1220|432
  484
  535| |50|1
  2
  3|115
  118
  121|798
  827
  854|294
  326
  357|140
  143
  147|1049
  1085
  1118|392
  433
  474|168
  172
  176|1334
  1379
  1421|506
  558
  611| |100|1
  2
  3|109
  113
  116|907
  933
  956|334
  368
  399|134
  138
  141|1222
  1253
  1282|454
  497
  540|161
  165
  169|1589
  1626
  1661|596
  651
  705|

  Col1	COMMON VENT CAPACITY	Col3	Col4	Col5	Col6	Col7	Col8	Col9	Col10
  	MINIMUM INTERNAL AREA OF MASONRY CHIMNEY FLUE (square inches)	MINIMUM INTERNAL AREA OF MASONRY CHIMNEY FLUE (square inches)	MINIMUM INTERNAL AREA OF MASONRY CHIMNEY FLUE (square inches)	MINIMUM INTERNAL AREA OF MASONRY CHIMNEY FLUE (square inches)	MINIMUM INTERNAL AREA OF MASONRY CHIMNEY FLUE (square inches)	MINIMUM INTERNAL AREA OF MASONRY CHIMNEY FLUE (square inches)	MINIMUM INTERNAL AREA OF MASONRY CHIMNEY FLUE (square inches)	MINIMUM INTERNAL AREA OF MASONRY CHIMNEY FLUE (square inches)	MINIMUM INTERNAL AREA OF MASONRY CHIMNEY FLUE (square inches)
  	63	63	63	78	78	78	113	113	113
  	**COMBINED APPLIANCE INPUT RATING