CWUIC · California Wildland-Urban Interface Code

How must exterior doors and garage door perimeter gaps be controlled?

Homeowners must prevent embers from entering through doors: exterior doors must be made of specified materials or tested assemblies, garage door openers need battery backups, and garage door gaps at the bottom, sides and top must be kept to **1/8 inch (3.2 mm)** or controlled with tested weather‑stripping, overlaps, or metal flashing in accordance with **§ 504.9, § 504.9.1, § 504.9.2,** and **§ 504.9.3** of the CWUIC.

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Last reviewed: July 6, 2026

What the code requires — 2-4 sentences

Exterior doors must be built of materials or assemblies that resist ignition (for example noncombustible, solid‑core wood ≥ 1 3/4 in (44 mm), or doors with a 20‑minute fire‑protection rating) as allowed by § 504.9. Garage doors and their openers have two specific requirements: automatic openers must have a battery backup (see § 504.9.1) and garage door perimeter gaps must be limited so embers cannot pass through—gaps at bottom, sides and top must not exceed 1/8 inch (3.2 mm) unless controlled by approved methods listed in § 504.9.2. The standard used to judge exterior door claddings is ASTM E2707 with the acceptance conditions in § 504.9.3.

The single most important practical rule: prevent ember intrusion at doors—keep gaps at door perimeters to 1/8 inch (3.2 mm) or use tested/approved materials or overlaps to block embers. § 504.9.2

Requirements in detail

1) What counts as an acceptable exterior door (materials / assembly)

  • Acceptable constructions include noncombustible doors, solid‑core wood not less than 1 3/4 inches (44 mm) thick, or doors constructed to the detailed solid‑core dimensions listed in § 504.9. Doors may alternatively have a 20‑minute fire protection rating (NFPA 252, UL 10B or UL 10C) or have an exterior surface/cladding that meets the ASTM E2707 performance requirements in § 504.9.3. § 504.9

  • Key performance thresholds to watch for on manufacturer labels / listings: 20 minutes fire rating, or test data showing compliance with ASTM E2707 or SFM Standard 12‑7A‑1 as allowed in § 504.9. § 504.9

2) Garage door electrical requirement

  • Automatic garage door openers that serve a residential building must be equipped with a battery backup function. § 504.9.1

3) Garage door perimeter gaps — the 1/8" rule and allowable control methods

  • The basic dimensional limit: exterior garage door gaps at the bottom, sides and top must not exceed 1/8 inch (3.2 mm) unless controlled by one of the approved methods in § 504.9.2. § 504.9.2

  • Approved methods to control gaps (any one or combination):

    1. Use weather‑stripping products made of materials that meet both testing conditions listed in § 504.9.2(1):
      • Tensile strength tested per ASTM D638 before and after exposure to ASTM G155 for 2,000 hours, with maximum allowable difference ≤ 10% between exposed and non‑exposed samples.
      • Flammability rating of UL 94 V‑2 or better when tested to UL 94. § 504.9.2(1)
    2. Provide door overlaps onto jambs and headers (i.e., physical overlapping construction that blocks ember entry). § 504.9.2(2)
    3. Cover garage door jambs and headers with metal flashing to block embers. § 504.9.2(3)

4) ASTM E2707 test and acceptance conditions (for exterior claddings)

  • If a door's exterior surface or cladding is claimed compliant by ASTM E2707 testing, the test must be conducted on at least three specimens and meet the two acceptance conditions in § 504.9.3. If 1 of 3 fails, the manufacturer must run 3 additional tests and all three must pass. § 504.9.3

  • The two acceptance conditions are:

    1. No flame penetration through the assembly at any time during the test.
    2. No evidence of glowing combustion on the interior surface at the end of the 70‑minute test. § 504.9.3

Quick reference table — decision‑relevant dimensions, values and tests

Topic Value / Requirement Code Reference
Maximum allowable gap at door perimeter (bottom/sides/top) 1/8 inch (3.2 mm) § 504.9.2
Weather‑stripping tensile stability ASTM D638 before & after ASTM G155 (2,000 hrs); Δ tensile ≤ 10% § 504.9.2(1.1)
Weather‑stripping flammability UL 94 V‑2 or better § 504.9.2(1.2)
Garage door opener power requirement Battery backup required for residential vehicle doors § 504.9.1
Door fire protection rating option 20 minutes (NFPA 252, UL 10B or UL 10C) § 504.9
Exterior surface/cladding performance test ASTM E2707 (3 specimens; no flame penetration; no glowing after 70 min) § 504.9.3

Exceptions & special cases

  • The code permits multiple compliance paths for exterior doors (noncombustible, specific solid‑core wood construction, a 20‑minute rating, or claddings tested per ASTM E2707). Choose the path that fits the product and installation; the code does not require all paths simultaneously. § 504.9

  • Weather‑stripping that satisfies the ASTM/UL tests in § 504.9.2(1) is an approved method to meet the 1/8 inch requirement; you can also use overlaps or metal flashing instead. Mixed solutions are allowed (e.g., flashing plus a compressible gasket). § 504.9.2

  • If a manufacturer claims ASTM E2707 compliance, verify the test report follows the specimen count and acceptance criteria in § 504.9.3; a single tested specimen that passed is not sufficient by itself. § 504.9.3

Common mistakes

  • Assuming any caulk or generic weather‑stripping is acceptable. To meet § 504.9.2, weather‑stripping must meet the specific ASTM D638 / ASTM G155 exposure criteria and UL 94 V‑2 flammability rating.

  • Measuring only the bottom gap and ignoring side and top gaps. The limit applies to bottom, sides and tops of doors. § 504.9.2

  • Relying on a manufacturer's claim of “ember resistant” without seeing the ASTM E2707 test report that meets § 504.9.3 acceptance criteria (3 specimens and the two acceptance items). § 504.9.3

  • Forgetting the opener requirement: residential automatic garage door openers must include a battery backup per § 504.9.1. § 504.9.1

Worked example — attached single‑car garage door retrofit

Scenario: A homeowner has a sectional garage door with an existing bottom gap of 3/16 in (4.8 mm) and side gaps around 1/16 in (1.6 mm). The homeowner wants to meet CWUIC requirements without replacing the whole door.

Steps applying the code:

  1. The code limit for perimeter gaps is 1/8 in (3.2 mm) at bottom, sides and top (§ 504.9.2) — the bottom gap (3/16 in) exceeds the limit. § 504.9.2
  2. Options to comply:
    • Install a compliant weather‑strip that compresses and will result in gaps ≤ 1/8 in when door is closed. Confirm the product’s data: tensile test per ASTM D638 before/after ASTM G155 (2000 hrs) with Δ ≤ 10%, and UL 94 V‑2 rating. If product test reports show that, the retrofit complies under § 504.9.2(1). § 504.9.2(1.1–1.2)
    • Or add a bottom seal (listed for WUI use) plus metal flashing on jambs/headers so the resulting effective gap is ≤ 1/8 in or is blocked by flashing — acceptable per § 504.9.2(2–3). § 504.9.2(2–3)
  3. Also verify the garage door opener has a battery backup (if the door is automatic) to meet § 504.9.1. § 504.9.1

Result: The homeowner chooses a UL‑rated, ASTM‑qualified compressible bottom seal that compresses to less than 1/8 in and installs metal flashing at the sides. They keep records of the seal’s test data and installer notes—this satisfies § 504.9.2 without replacing the door. § 504.9.2

Related provisions

  • § 504.9 — Exterior doors (materials, fire rating, ASTM E2707 option).
  • § 504.9.1 — Garage door openers: battery backup requirement.
  • § 504.9.2 — Garage door perimeter gap limits and approved control methods.
  • § 504.9.3 — ASTM E2707 test conditions of acceptance (no flame penetration; no glowing combustion at 70 minutes).
  • See also: § 504.8 (exterior glazing requirements) and Appendix G home‑hardening recommendations on weather‑stripping and caulking (useful guidance for owners).

Code references

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

  • CWUIC § 504.9 High relevance — show source text

    504.9 Exterior doors. Exterior doors shall be constructed in accordance with any of the following:

    1. Noncombustible construction .

    2. Solid-core wood not less than 1 [3] / 4 inches thick (44 mm) . 3. The exterior door shall be constructed of solid core wood that complies with the following requirements: 3.1. Stiles and rails shall not be less than 1 3/8 inches (35 mm) thick. 3.2. Raised panels shall not be less than 11/4 inches (32 mm) thick, except for the exterior perimeter of the raised panel that shall be permitted to taper to a tongue not less than 3/8 inch (10 mm) thick. 4. Have a fire protection rating of not less than 20 minutes when tested according to NFPA 252, UL 10B or UL 10C . 5. The exterior surface or cladding meeting the performance requirements of Section 504.9.3 when tested in accordance with ASTM E2707.

    6. The exterior surface or cladding shall be tested to meet the performance requirements of SFM Standard 12-7A-1.

    Windows within doors and glazed doors shall be in accordance with Section 504.8.

    504.9.1 Garage doors. Automatic garage door openers for vehicle doors serving a residential building shall be equipped with a battery backup function.

    504.9.2 Garage door perimeter gap. Exterior garage doors shall resist the intrusion of embers by preventing gaps between doors and door openings, at the bottom, sides and tops of doors, from exceeding [1] / 8 inch (3.2 mm). 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

    5-8 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE

  • CWUIC § 504.9.3 High 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 § 3.2 High relevance — show source text

    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. Openings beneath decks which are four feet (1219 mm) or less above grade can be covered with a noncombustible and corrosion- resistant mesh with [1] / 16 -inch (1.6 mm) to [1] / 8 -inch (3.2 mm) openings. 14. Remove or replace combustible fences within 5 feet (1524 mm) of the structure. Detached fences that are located within 5 feet (1524 mm) of the structure should be replaced with noncombustible or ignition-resistant building materials.

    G101.3 Defensible space features. The maintenance and defensible space features listed in Section G101.3.1 were developed as a best practices guide to assist homeowners to increase the effectiveness of their defensible space and improve the effects of the home-harden- ing features to increase the survivability of their homes from wildfires.

    2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE APPENDIX G-3

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    APPENDIX G—VOLUNTARY HOME-HARDENING RECOMMENDATIONS

    G101.3.1 Maintenance and defensible space. The following maintenance and operational procedures assist to limit the impact on a home from an approaching wildfire. 1. Roofs—regularly clean your roof, including roof-to-wall intersections and skylights to remove accumulated fallen leaves, needles and other flammable materials; repair damaged or deteriorated sections of the roof or roof covering; remove all trees, branches, shrubs or other plants adjacent to or overhanging buildings. 2. Rain gutters—keep roof gutters free of combustible debris. 3. Decks—regularly clean your deck, including deck-to-wall intersections to avoid the accumulation of fallen leaves, needles and other flammable materials; ensure that all combustible materials are removed from underneath, on top of or within five feet (1524 mm) of a deck or balcony. _4.

  • CWUIC § 504.8 High relevance — show source text

    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.

    3. Glazing with a fire-protection rating of not less than 20 minutes when tested according to NFPA 257 or UL 9, and shall be exempt from the hose stream test. 4. Glazing meeting the performance requirements of SFM Standard 12-7A-2.

    504.8.1 Structural glass veneer. The wall assembly behind structural glass veneer shall comply with Section 504.5.

    504.8.2 Operable skylights. Operable skylights shall be protected by a noncombustible mesh screen and the dimensions of the openings in the screen shall not exceed [1] / 8 inch (3.2 mm).

    504.9 Exterior doors. Exterior doors shall be constructed in accordance with any of the following:

    1. Noncombustible construction .

    2. Solid-core wood not less than 1 [3] / 4 inches thick (44 mm) . 3. The exterior door shall be constructed of solid core wood that complies with the following requirements: 3.1. Stiles and rails shall not be less than 1 3/8 inches (35 mm) thick. 3.2. Raised panels shall not be less than 11/4 inches (32 mm) thick, except for the exterior perimeter of the raised panel that shall be permitted to taper to a tongue not less than 3/8 inch (10 mm) thick. 4. Have a fire protection rating of not less than 20 minutes when tested according to NFPA 252, UL 10B or UL 10C . 5. The exterior surface or cladding meeting the performance requirements of Section 504.9.3 when tested in accordance with ASTM E2707.

    6. The exterior surface or cladding shall be tested to meet the performance requirements of SFM Standard 12-7A-1.

    Windows within doors and glazed doors shall be in accordance with Section 504.8.

    504.9.1 Garage doors. Automatic garage door openers for vehicle doors serving a residential building shall be equipped with a battery backup function.

    504.9.2 Garage door perimeter gap. Exterior garage doors shall resist the intrusion of embers by preventing gaps between doors and door openings, at the bottom, sides and tops of doors, from exceeding [1] / 8 _inch (3.2 mm).

  • CWUIC § 3.2 High relevance — show source text

    _ 2. Rain gutters—keep roof gutters free of combustible debris. 3. Decks—regularly clean your deck, including deck-to-wall intersections to avoid the accumulation of fallen leaves, needles and other flammable materials; ensure that all combustible materials are removed from underneath, on top of or within five feet (1524 mm) of a deck or balcony. 4. Chimneys—ensure spark arrestor is in place; remove all branches within 10 feet of any chimney or stovepipe outlet. 5. Windows—remove or relocate all combustibles away from windows. Older windows that are single-pane or double-pane without tempering can be vulnerable to direct flame contact or radiant heat exposure; remove vegetation or other combus- tible materials that are within five feet of windows.

    6. Doors—inspect the door for dry rot, gaps, cracks and warping and caulk or plug gaps greater than [1] / 8 inch. Install weather stripping to fill gaps greater than [1] / 8 inch (3.2 mm) between garage doors and door frames to prevent ember intrusion; remove vegetation or other combustible materials that are within five feet (1524 mm) of doors. 7. Exterior walls—inspect exterior siding for dry rot, gaps, cracks and warping and caulk or plug gaps greater than [1] / 8 inch in siding and replace any damaged boards, including those with dry rot. 8. Firewood—exposed firewood is stored at least 30 feet (9144 mm) away from structures or completely covered in a fire-resis- tant material that will not allow embers to penetrate. Additionally, make sure you have 10 feet (3048 mm) of clearance around your wood piles. 9. Fences—remove or relocate all vegetation, combustibles and combustible debris adjacent to and underneath fences. 10. Replace wood mulch products within five feet (1524 mm) of all structures with noncombustible products such as dirt, stone, or gravel. 11. Remove all dead or dying grass, plants, shrubs, trees, branches, leaves, weeds, and pine needles within 30 feet (9144 mm) of all structures or to the property line. 12. Be sure to store combustible outdoor furnishings away from your home when not in use. 13. Remember to properly store retractable awnings and umbrellas when not in use so they do not collect leaves and embers.

    APPENDIX G-4 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE

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    CALIFORNIA WILDLAND-URBAN INTERFACE CODE – MATRIX ADOPTION TABLE

    APPENDIX H – REFERENCED CALIFORNIA DOCUMENTS

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

    (Not adopted by the State Fire Marshal)

  • CWUIC § 2.1 High 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 § 7.1 Medium relevance — show source text

    7.1|Underside of
    projections|Y||707A.9,
    707A.10||||||| |504.7.2|Conditions of accep-
    tance for ASTM E2957|Y||707A.11||||||| |504.7.3|Decks|Y||709A.1||||||| |504.7.3.1|Flashing|Y||709A.1.1||||||| |504.7.3.2|Decking surfaces|Y||709A.3||||||| |504.7.3.3|Performance require-
    ments for Section
    504.7.3.2, Item 1|Y||709A.4.2||||||| |504.7.3.3.1|Conditions of accep-
    tance for ASTM E2632|Y||709A.4.1||||||| |504.7.3.3.2|Conditions of accep-
    tance for ASTM E2726|Y||709A.4.2||||||| |504.7.3.4|Performance require-
    ments for Section
    504.7.3.2, Item 7|Y||709A.5||||||| |504.8|Exterior glazing|Y||708A.2.1||||||| |504.8.1|Structural glass
    veneer|Y||708A.2.2||||||| |504.8.2|Operable skylights|Y||708A.2.3||||||| |504.9|Exterior doors|Y||708A.3|||||||

    2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE APPENDIX H-29

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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 5 Special building construction regulations Special building construction regulations Special building construction regulations Special building construction regulations Special building construction regulations Special building construction regulations Special building construction regulations Special building construction regulations Special building construction regulations Special building construction regulations
    504.9.1 Garage doors Y
    504.9.2 Garage door
    perimeter gap    		 Y 708A.4
    504.9.3 Conditions of accep-
    tance for ASTM E2707    		 Y 707A.4.1
    504.10 Vents Y 706A.1
    504.10.
  • CWUIC § 2.79 Medium relevance — show source text

    I|2.79 ×TDA + 8.70|AHRI 1200| |Commercial ice-
    cream freezers|Remote (RC)|Semivertical Open
    (SVO)|Semivertical Open
    (SVO)|Semivertical Open
    (SVO)|SVO.RC.I|2.79 ×TDA + 8.70|2.79 ×TDA + 8.70| |Commercial ice-
    cream freezers|Remote (RC)|Horizontal Open
    (HZO)|Horizontal Open
    (HZO)|Horizontal Open
    (HZO)|HZO.RC.I|0.70 ×TDA + 8.74|0.70 ×TDA + 8.74| |Commercial ice-
    cream freezers|Remote (RC)|Vertical Closed
    Transparent (VCT)|Vertical Closed
    Transparent (VCT)|Vertical Closed
    Transparent (VCT)|VCT.RC.I|0.58 ×TDA + 3.05|0.58 ×TDA + 3.05| |Commercial ice-
    cream freezers|Remote (RC)|Horizontal Closed
    Transparent (HCT)|Horizontal Closed
    Transparent (HCT)|Horizontal Closed
    Transparent (HCT)|HCT.RC.I|0.40 ×TDA + 0.31|0.40 ×TDA + 0.31| |Commercial ice-
    cream freezers|Remote (RC)|Vertical Closed
    Solid (VCS)|Vertical Closed
    Solid (VCS)|Vertical Closed
    Solid (VCS)|VCS.RC.I|0.25 ×V + 0.63|0.25 ×V + 0.63| |Commercial ice-
    cream freezers|Remote (RC)|Horizontal Closed
    Solid (HCS)|Horizontal Closed
    Solid (HCS)|Horizontal Closed
    Solid (HCS)|HCS.RC.I|0.25 ×V + 0.63|0.25 ×V + 0.63| |Commercial ice-
    cream freezers|Remote (RC)|Service Over
    Counter (SOC)|Service Over
    Counter (SOC)|Service Over
    Counter (SOC)|SOC.RC.I|1.09 ×TDA + 0.26|1.09 ×TDA + 0.26| |Commercial ice-
    cream freezers|Self-contained
    (SC)|Vertical Open
    (VOP)|Vertical Open
    (VOP)|Vertical Open
    (VOP)|VOP.SC.I|5.40 ×TDA + 15.02|AHRI 1200| |Commercial ice-
    cream freezers|Self-contained
    (SC)|Semivertical Open
    (SVO)|Semivertical Open
    (SVO)|Semivertical Open
    (SVO)|SVO.SC.I|5.41 ×TDA + 14.63|5.41 ×TDA + 14.63| |Commercial ice-
    cream freezers|Self-contained
    (SC)|Horizontal Open
    (HZO)|Horizontal Open
    (HZO)|Horizontal Open
    (HZO)|HZO.SC.I|2.42 ×TDA + 9.00|2.42 ×TDA + 9.

  • CWUIC § 3.1 Medium relevance — show source text

    Detached fences that are located within 5_ feet (1524 mm) of the structure should be replaced with noncombustible or ignition-resistant building materials.

    G101.3 Defensible space features. The maintenance and defensible space features listed in Section G101.3.1 were developed as a best practices guide to assist homeowners to increase the effectiveness of their defensible space and improve the effects of the home-harden- ing features to increase the survivability of their homes from wildfires.

    2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE APPENDIX G-3

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    APPENDIX G—VOLUNTARY HOME-HARDENING RECOMMENDATIONS

    G101.3.1 Maintenance and defensible space. The following maintenance and operational procedures assist to limit the impact on a home from an approaching wildfire. 1. Roofs—regularly clean your roof, including roof-to-wall intersections and skylights to remove accumulated fallen leaves, needles and other flammable materials; repair damaged or deteriorated sections of the roof or roof covering; remove all trees, branches, shrubs or other plants adjacent to or overhanging buildings. 2. Rain gutters—keep roof gutters free of combustible debris. 3. Decks—regularly clean your deck, including deck-to-wall intersections to avoid the accumulation of fallen leaves, needles and other flammable materials; ensure that all combustible materials are removed from underneath, on top of or within five feet (1524 mm) of a deck or balcony. 4. Chimneys—ensure spark arrestor is in place; remove all branches within 10 feet of any chimney or stovepipe outlet. 5. Windows—remove or relocate all combustibles away from windows. Older windows that are single-pane or double-pane without tempering can be vulnerable to direct flame contact or radiant heat exposure; remove vegetation or other combus- tible materials that are within five feet of windows.

    6. Doors—inspect the door for dry rot, gaps, cracks and warping and caulk or plug gaps greater than [1] / 8 inch. Install weather stripping to fill gaps greater than [1] / 8 inch (3.2 mm) between garage doors and door frames to prevent ember intrusion; remove vegetation or other combustible materials that are within five feet (1524 mm) of doors. 7. Exterior walls—inspect exterior siding for dry rot, gaps, cracks and warping and caulk or plug gaps greater than [1] / 8 inch in siding and replace any damaged boards, including those with dry rot. 8. Firewood—exposed firewood is stored at least 30 feet (9144 mm) away from structures or completely covered in a fire-resis- _tant material that will not allow embers to penetrate.

  • CWUIC § 1.5 Medium relevance — show source text

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    APPENDIX H—REFERENCED CALIFORNIA DOCUMENTS

    2025 CWUIC—continued Col2 Adopted
    Yes/No    		 IWUIC
    Section    		 CBC
    Section    		 CFC
    Section    		 Title 14,
    Division 1.5
    Section    		 Title 19,
    Division 1
    Section    		 Gov Code
    Section    		 PRC
    Section    		 HSC
    Section
    Section Title Title Title Title Title Title Title Title Title Title
    Chapter 2 Definitions Definitions Definitions Definitions Definitions Definitions Definitions Definitions Definitions Definitions
    Multilayered glazed
    panels    		 Y
    Noncombustible roof
    covering    		 Y
    Outbuilding (T14) Y 1299.02(c)
    Peer review Y
    Rafter tail Y 702A
    Registered design
    professional    		 Y
    Residential unit (T14) Y 1270.01(w)
    Ridgeline
    (topography) (T14)    		 Y 1270.01(x)
    Road (T14) Y 1270.01(y)
    Roof assembly Y
    Roof covering Y
    Roof covering system Y
    Roof deck Y
    Roof eave Y 702A
    Roof eave soffit Y 702A
    Slope Y
    State Responsibility
    Area (SRA)    		 Y 702A 4902.1
    Strategic
    ridgeline (T14)    		 Y 1270.01(dd)
    Structure Y 202 1270.01(ee)
    Subdivision Y
    Tree crown Y
    Undeveloped
    ridgeline (T14)    		 Y 1270.01(ii)
    Unenclosed acces-
    sory structure    		 Y
    Vertical curve (T14) Y 1270.01(k)
    Wildfire Y 702A 4902.1
    Wildfire exposure Y 702A 4902.1
    Wildland Y
    Wildland-urban inter-
    face area    		 Y 702A 4902.1
    Chapter 3 Wildland-urban interface areas Wildland-urban interface areas Wildland-urban interface areas Wildland-urban interface areas Wildland-urban interface areas Wildland-urban interface areas Wildland-urban interface areas Wildland-urban interface areas Wildland-urban interface areas Wildland-urban interface areas
    301 General Y
    301.1 Scope Y 4201
    301.
  • CWUIC § 1010.3.3 Medium relevance — show source text

    [BE] 1010.3.3 Special-purpose horizontal sliding, accordion or folding doors. In other than Group H occupancies, specialpurpose horizontal sliding, accordion, or folding door assemblies permitted to be a component of a means of egress in accordance with Exception 6 to Section 1010.1.2 shall comply with all of the following criteria:

    1. The doors shall be power operated and shall be capable of being operated manually in the event of power failure.
    2. The doors shall be openable by a simple method without special knowledge or effort from the egress side or sides.
    3. The force required to operate the door shall not exceed 30 pounds (133 N) to set the door in motion and 15 pounds (67 N) to close the door or open it to the minimum required width.
    4. The door shall be openable with a force not to exceed 15 pounds (67 N) when a force of 250 pounds (1100 N) is applied perpendicular to the door adjacent to the operating device.
    5. The door assembly shall comply with the applicable fire protection rating and, where rated, shall be self-closing or automatic closing by smoke detection in accordance with Section 716.2.6.6 of the California Building Code, shall be installed in accordance with NFPA 80 and shall comply with Section 716 of the California Building Code .
    6. The door assembly shall have an integrated standby power supply.
    7. The door assembly power supply shall be electrically supervised.
    8. The door shall open to the minimum required width within 10 seconds after activation of the operating device.

    [BE] 1010.3.4 Security grilles. In Groups B, F, M and S, horizontal sliding or vertical security grilles are permitted at the main exit and shall be openable from the inside without the use of a key or special knowledge or effort during periods that the space is occupied. The grilles shall remain secured in the full-open position during the period of occupancy by the general public. Where two or more exits or access to exits are required, not more than one-half of the exits or exit access doorways shall be equipped with horizontal sliding or vertical security grilles.

    [BE] 1010.4 Gates. Gates serving the means of egress system shall comply with the requirements of this section. Gates used as a component in a means of egress shall conform to the applicable requirements for doors.

    [BE] 1010.4.1 Stadiums. Panic hardware is not required on gates surrounding stadiums where such gates are under constant immediate supervision while the public is present, and where safe dispersal areas based on 3 square feet (0.28 m [2] ) per occupant are located between the fence and enclosed space. Such required safe dispersal areas shall not be located less than 50 feet (15 240 mm) from the enclosed space. See Section 1028.5 for means of egress from safe dispersal areas.

    [BE] 1010.5 Turnstiles and similar devices. Turnstiles or similar devices that restrict travel to one direction shall not be placed so as to obstruct any required means of egress, except where permitted in accordance with Sections 1010.5.1, 1010.5.2 and 1010.5.3.

  • CWUIC § 1270.01 Medium relevance — show source text

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

    APPENDIX H-26 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    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,

Frequently asked questions

What is the single easiest retrofit to stop ember intrusion at a garage door?

Installing tested, compressible weather‑stripping that reduces the effective gap at the bottom and sides to ≤ 1/8 in (3.2 mm) — but be sure the product meets the ASTM/UL criteria in § 504.9.2(1).

Can I rely on a manufacturer’s marketing claim “ember resistant”?

Only if the manufacturer provides test documentation showing compliance with ASTM E2707 (and the acceptance criteria in § 504.9.3) or shows the weather‑stripping meets the ASTM/UL tests required in § 504.9.2(1).

Do all exterior doors have to be replaced to meet CWUIC?

No. The code provides multiple compliance paths: use of noncombustible doors, specific solid‑core wood dimensions, a 20‑minute fire rating, or doors whose exterior surface/cladding passes ASTM E2707. Choose the appropriate path; replacement is not always required. § 504.9

Is the gap limit only for the bottom of the garage door?

No. The 1/8 in (3.2 mm) limit applies to bottom, sides and tops of exterior garage doors and door openings unless controlled by approved methods in § 504.9.2.

If one of three ASTM E2707 specimens fails, is the product acceptable?

No. If any one of the initial three tests fails, the manufacturer must perform three additional tests and all three of those additional tests must meet the acceptance conditions in § 504.9.3.

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