CWUIC · California Wildland-Urban Interface Code

What test methods apply to decking (burning-brand and heat-release tests)?

Summary: Under the California Wildland‑Urban Interface Code, decking must either be of approved ignition‑resistant or noncombustible materials or pass specific fire tests: an under‑deck heat‑release test (ASTM E2632) with a peak HRR ≤ 25 kW/ft², a burning‑brand exposure test (ASTM E2726) with no sustained flaming or burning particles after 40 minutes, and surface‑burning tests (ASTM E84/UL723) — with special weathering retest rules for composites and plastic lumber.

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Last reviewed: July 6, 2026

What the code requires — 2-4 sentences

Deck walking surfaces (decks, porches, balconies, stairs) must meet specific fire-performance tests or be made of specified materials under § 504.7.3.2. Where the code requires performance testing, the decking material must be tested for under‑deck heat‑release (ASTM E2632), burning‑brand exposure (ASTM E2726), and also meet surface‑burning performance (ASTM E84 / UL 723) per § 504.7.3.3 and the ignition‑resistant material rules in § 503.2.4.

The single most important rule: if a decking product is being accepted by performance testing it must show (1) acceptable peak heat‑release in the under‑deck test and (2) no sustained flaming or burning, and no flaming particles in the burning‑brand test — and it must also meet the surface burning (E84/UL723) requirements in § 503.2.4.

Requirements in detail

Which tests are required (high level)

  • ASTM E2632 — Under‑deck heat‑release rate (HRR) deck assembly combustion test (Part A). Required by § 504.7.3.3 when Item 1 of § 504.7.3.2 is used.
  • ASTM E2726 — Deck burning‑brand (upper surface brand) sustained combustion test (Part B). Required by § 504.7.3.3.
  • ASTM E84 or UL 723 — Surface‑burning characteristics (flame spread) on front and back faces (extended 30‑minute exposure), per § 503.2.4 and required by § 504.7.3.3.

Bold, decision‑relevant numeric thresholds and test conditions:

Decision dimension Required value / test method Code Reference
Under‑deck burner output (E2632 / SFM 12‑7A‑4) 80 ± 4 kW direct flame for 3 minutes (then observe) § 504.7.3.3; SFM 12‑7A‑4 procedures
Effective net peak heat release ≤ 25 kW/ft² (269 kW/m²) (three replicates; if any fail, run three more) § 504.7.3.3.1
Burning‑brand wind velocity (E2726 / SFM 12‑7A‑4 Part B) 12 mph (≈5.4 m/s) airflow; Class A brand (12" × 12" × 2.25") for 40 minutes § 504.7.3.3.2; SFM 12‑7A‑4 Part B
Burning‑brand acceptance criteria No sustained flaming or glowing at end of 40‑min and no flaming particles that burn when falling to floor § 504.7.3.3.2 (and § 504.7.3.3.1 for E2632)
Surface burning (flame spread) ASTM E84 / UL 723 — extended test, front & back faces, flame spread index ≤ 25 for ignition‑resistant materials (see § 503.2.4.1) § 503.2.4 and § 503.2.4.1
Weathering evaluation — wood‑plastic composites ASTM E1354 @ 50 kW/m² (horizontal) → weather per ASTM D7032 → retest E1354; ≤ 10% increase in peak HRR allowed § 503.2.4.3.2
Weathering evaluation — plastic lumber ASTM E1354 @ 50 kW/m² (horizontal) → weather per ASTM D6662 → retest E1354; ≤ 10% increase in peak HRR allowed § 503.2.4.3.3

(See SFM Standard 12‑7A‑4 and 12‑7A‑4A for full test assembly, burner positioning, specimen size and reporting rules.)

Test replication, reporting and pass/fail logic

  • Minimum three replicates for ASTM E2632 and ASTM E2726; if any one of the three fails the acceptance criteria, the manufacturer/test lab must run three additional tests and all three additional tests must pass (i.e., passing is based on meeting the acceptance criteria across required replicates). § 504.7.3.3.1 / .3.2
  • For E2632 HRR reporting, SFM 12‑7A‑4 requires calculation of effective net peak HRR (subtracting the 80 kW burner during the initial 3‑minute exposure) and reporting HRR normalized to deck surface area. SFM test reporting rules apply.

Exceptions & special cases

  • If a decking product demonstrates compliance with ASTM E84 / UL 723 with a Class B flame‑spread index, the attached exterior wall material may be of any material that otherwise complies with the chapter (i.e., the code permits a wall‑material exception when decking meets E84 Class B) — see the exception to § 504.7.3.2.
  • Decking may alternatively comply by meeting SFM Standard 12‑7A‑4A (the Alternate Method A: heat‑release test) or SFM 12‑7A‑4 if accompanied by specified wall coverings that are noncombustible or ignition‑resistant — see Items 3, 6 and 7 of § 504.7.3.2 and the SFM standards.
  • Panel products (e.g., cladding with combustible core) are tested with a ripped or cut longitudinal gap of 1/8" (3.2 mm) unless they have a qualifying metal exterior covering per § 503.2.4 exception.

Common mistakes

  • Confusing units or thresholds — HRR acceptance is 25 kW/ft² (269 kW/m²), not kW/m² alone; be careful to use the code’s units and the required conversion when comparing lab reports. § 504.7.3.3.1
  • Using only ASTM E84 when the code requires both the E2632 (heat‑release) and E2726 (burning‑brand) tests for the § 504.7.3.2, Item 1 pathway. § 504.7.3.3
  • Forgetting the front‑and‑back extended E84 exposure mandated in § 503.2.4 (30‑minute total), or failing to test panel products with the required longitudinal rip. § 503.2.4
  • Applying the weathering acceptance incorrectly: wood‑plastic composites and plastic lumber require the E1354 → D7032/D6662 weathering → E1354 retest cycle with ≤ 10% increase threshold per § 503.2.4.3.2/.3.3.
  • Not labeling products or failing to use an approved testing agency. Section § 503.3.3 requires identification labels showing fire test results and approved‑agency reporting.

Worked example — concrete scenario

Manufacturer X submits a new wood‑plastic composite deck board:

  1. Lab runs ASTM E2632 (under‑deck HRR) on three specimens. Reported effective net peak HRRs are 22, 18, and 24 kW/ft² → all ≤ 25 kW/ft², so pass the E2632 HRR condition in § 504.7.3.3.1.
  2. Lab runs ASTM E2726 burning‑brand exposure (three replicates) per SFM 12‑7A‑4 Part B: no sustained flaming at 40 minutes and no flaming particles reached the floor → passes § 504.7.3.3.2.
  3. Lab runs ASTM E84 (extended 30‑minute front‑and‑back) and reports a flame spread index = 18 → meets § 503.2.4.1 (≤ 25).
  4. For weathering (as a wood‑plastic composite), the product undergoes ASTM E1354 at 50 kW/m², then ASTM D7032 weathering, then E1354 retest. Peak HRR increases from 120 kW/m² to 128 kW/m² (an increase of 6.7%) → within the ≤ 10% limit in § 503.2.4.3.2, so passes weathering requirement.

Conclusion: Manufacturer X can claim compliance with the performance pathway in § 504.7.3.2, Item 1, provided testing and labeling follow the code and SFM reporting rules.

Related provisions

  • § 504.7.3.2 — Decking surfaces: acceptable materials and how the testing pathways are used.
  • § 504.7.3.3 — Performance requirements and acceptance criteria for ASTM E2632 and ASTM E2726 (including HRR limit and burning‑brand criteria).
  • § 503.2.4 — Other ignition‑resistant building material: E84/UL723 extended testing and general flame‑spread/flame‑front rules.
  • § 503.2.4.3.2 — Weathering + retest procedure for wood‑plastic composite materials (E1354 → D7032 → E1354, ≤ 10% increase).
  • § 503.2.4.3.3 — Weathering + retest procedure for plastic lumber (E1354 → D6662 → E1354, ≤ 10% increase).

Code references

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 § 11.3.4 High relevance — show source text

    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

    252—2022: Standard on Fire Test of Door Assemblies

    504.9

    257—2022: Standard on Fire Test for Window and Glass Block Assemblies

    504.8

    CEC—2025: California Electrical Code

    201.3

    SFM State of California, Department of Forestry and Fire Protection, Office of the State Fire Marshal, P.O. Box 944246, Sacramento, CA 94246-2460

    12-7A-1: Exterior Wall Siding and Sheathing. A fire resistance test standard consisting of a 150 kW intensity direct flame exposure for a 10-minute duration

    504.5, 504.9

    12-7A-2: Exterior Windows. A fire resistance test standard consisting of a 150 kW intensity direct flame exposure for an 8-minute duration

    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

  • CWUIC § 504.7.3.3 High 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.

  • CWUIC § 504.7.3.2 High relevance — show source text

    504.7.3.2 Decking surfaces. The walking surface material of decks, porches, balconies and stairs shall be constructed with any of the following materials: 1. Material that complies with the performance requirements of Section 504.7.3.3 when tested in accordance with ASTM E2632 and ASTM E2726.

    2. Ignition-resistant building material that complies with the performance requirements of Section 503.2.4. 3. Material that complies with the performance requirements of both SFM Standard 12-7A-4 and Section 503.2.4. 4. Fire-retardant-treated wood labeled for exterior use and complying with Section 2303.2 of the California Building Code.

    5. Noncombustible material.

    6. Any material that complies with the performance requirements of SFM Standard 12-7A-4A and any attached exterior wall covering that is noncombustible or ignition-resistant building materials. Exception: Wall material shall be permitted to be of any material that otherwise complies with this chapter when the decking surface material complies with the performance requirements of ASTM E84 or UL 723 with a Class B flame spread index.

    7. Any material that complies with the performance requirements of Section 504.7.3.4 when tested in accordance with ASTM E2632 and any attached exterior wall covering that is noncombustible or ignition-resistant building materials. Exception: Wall material shall be permitted to be of any material that otherwise complies with this chapter when the decking surface material complies with the performance requirements of ASTM E84 or UL 723 with a Class B flame spread index.

    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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    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.

  • CWUIC § 1.8 High relevance — show source text

    403.1.8, 1273.10

    ASTM ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959

    D638—2022: Standard Test Method for Tensile Properties of Plastics

    504.9.1

    D2898—10(2017): Standard Practice for Accelerated Weathering of Fire-Retardant-Treated Wood for Fire Testing

    503.2.4.3.1

    D3909/D3909M— 2022 : Standard Specification for Asphalt Roll Roofing (Glass Felt) Surfaced With Mineral Granules

    504.2.1.1, 504.2.2

    D6662—22: Standard Specification for Polyolefin-Based Plastic Lumber Decking Boards

    503.2.4.3.3

    D7032—21: Standard Specification for Establishing Performance Ratings for Wood-Plastic Composite and Plastic Lumber Deck Boards, Stair Treads, Guards, and Handrails

    503.2.4.3.2

    E84— 2023d : Standard Test Method for Surface Burning Characteristics of Building Materials

    202, 501.4.1, 503.2.4, 504.7.3.2, 504.7.3.3

    E108—20a: Standard Test Methods for Fire Tests of Roof Coverings

    504.2, 504.2.1.2, 504.11.6, G101.2.1

    E119— 2022 : Standard Test Methods for Fire Tests of Building Construction and Materials

    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

  • CWUIC § 7.1. High relevance — show source text
    1. Procedure.

    7.1. Ignition. Ignite the burner, controlling for a constant 80 ± 4 kW output. 7.2. Flame exposure. Continue the exposure for a 3-minute period. Extinguish the burner.

    7.3. Continued combustion. Continue observation for an additional 40 minutes or until all combustion has ceased.

    1. Observations. Note physical changes of the deck boards during the test, including structural failure of any deck board, location of flaming and glowing ignition, and loss of material (i.e., flaming drops of particles falling from the deck). It is desirable to capture the entire test with a video recorder to allow review of the details of performance.

    12-7A-4.7.4 Report. The report shall include a description of the deck board material and the time of any degradation (effective net peak heat release rate, structural failure, flaming drops or particles falling from the deck) during the test.

    1. Calculated rate of heat release. The effective net peak heat release rate (HRR) shall be calculated as follows: 1.1. During the first 5 minutes of the test (the 3 minutes during which the ignition source burner is operating and the immediately following 2 minutes) the effective net peak HRR of the test assembly shall be reported as: effective net peak HRR = (peak heat release rate – 80 kW) / (deck surface area). 1.2. During the remaining test duration the effective net peak heat release rate of the test assembly shall be reported as: effective net peak HRR = (peak heat release rate) / (deck surface area).

    12-7A-4.7.5 Conditions of Acceptance. Should one of the three replicates fail to meet the Conditions of Acceptance, three additional tests may be run. All of the additional tests must meet the Conditions of Acceptance.

    1. Effective net peak heat release rate of less than or equal to 25 kW/ft [2] (269 kW/m [2] ).
    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.

    12-7A-4.8 PART B. Burning brand exposure.

    12-7A-4.8.1 Equipment.

    1. Wind tunnel. The wind tunnel shall have the capability of providing 12 mph (5.4 m/s) airflow over the deck assembly.
    2. Anemometer. Device for measuring airflow across the deck.
    3. Burner. Gas-fueled burner for brand ignition.

    12-7A-4.8.2 Test system preparation. See Figure 2. The ASTM E108 “A” brand roof test apparatus is to be used, with the following modifications:

    1. Deck support. The deck shall be supported horizontally with the center 60 inches (150 mm) from the front opening of the wind tunnel and the joists parallel to the airflow and resting on two transverse metal supports. The top surfaces of these supports, no more than 3 inches (75 mm) wide, are at the same height as the floor of the wind tunnel.
    2. Fragments. Burning fragments shall be free to fall to the floor of the room.

    12-7A-4.8.3 Conduct of tests.

    1. Number of tests. Conduct the test on three replicate assemblies.
    2. **Moisture content.
  • CWUIC § 4.4.2 High relevance — show source text

    All other measurement details shall be followed as specified in Sections 4.4.2, 4.4.3 and 4.4.4 of ASTM E108. Although ASTM E108 specifies calibration to be conducted with the 33-inch (840-mm) framework spacing used for the intermittent flame test set up, tests have shown that at the nominal 12 mph

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    MATERIALS AND CONSTRUCTION METHODS FOR EXTERIOR WILDFIRE EXPOSURE

    setting, there was not difference in measured velocity between the 33- and 60-inch (838 mm and 1524 mm) framework spacing. 3.2. Mount the test specimen at a zero horizontal incline positioned 60 inches (1.5 m) from the front opening of the wind tunnel.

    3.3. Ignite the “A” brands as specified in Section 9.4 of ASTM E108 as reprinted here:

    1. Each 12- x 12-inch (300 x 300 mm) face for 30 seconds.
    2. Each 2.25- x 12-inch (57 x 300 mm) edge for 45 seconds.
    3. Each 12- x 12-inch (300 x 300 mm) face again for 30 seconds. 3.4. Center the burning brand laterally on the deck with the front edge 2.5 inches (64 mm) from the entering air edge of the deck.

    3.5. Continue the exposure for a 40-minute period or until all combustion of the deck boards ceases. The test shall be terminated immediately if flaming combustion accelerates uncontrollably (runaway combustion) or structural failure of any deck board occurs. Heat Release Rate is not monitored because of the impracticability with the specified airflow. 4. Observations. Note physical changes of the deck boards during the test, including deformation from the horizontal plane, location of flaming and glowing combustion, and loss of material (i.e., flaming drops of particles falling from the deck). It is desirable to capture the entire test with a video recorder to allow review of the details of performance.

    12-7A-4.8.4 Report. The report shall include description of the deck board material, and the time of any degradation (accelerated combustion, board collapse, flaming drops or particles falling from the deck).

    12-7A-4.8.5 Conditions of Acceptance. Should one of the three replicates fail to meet the Conditions of Acceptance, three additional tests may be run. All of the 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.

    FIGURE 1 — DECK TEST ASSEMBLY (UNDER DECK-FLAME)

    FIGURE 2 — DECK TEST ASSEMBLY (BURNING-BRAND)

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    MATERIALS AND CONSTRUCTION METHODS FOR EXTERIOR WILDFIRE EXPOSURE

    DECKING ALTERNATE METHOD A

    SFM STANDARD 12-7A-4A

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

    12-7A-4.8.4 Report. The report shall include description of the deck board material, and the time of any degradation (accelerated combustion, board collapse, flaming drops or particles falling from the deck).

    12-7A-4.8.5 Conditions of Acceptance. Should one of the three replicates fail to meet the Conditions of Acceptance, three additional tests may be run. All of the 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.

    FIGURE 1 — DECK TEST ASSEMBLY (UNDER DECK-FLAME)

    FIGURE 2 — DECK TEST ASSEMBLY (BURNING-BRAND)

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    DECKING ALTERNATE METHOD A

    SFM STANDARD 12-7A-4A

    12-7A-4A.1 Application. The minimum design, construction and performance standards set forth herein for unloaded decks are those deemed necessary to establish conformance to the provisions of these regulations. Materials and assemblies that meet the performance criteria of this standard are acceptable for use as defined in the California Building Standards Code.

    12-7A-4A.2 Scope. This standard evaluates the performance of decks (or other horizontal ancillary structures in close proximity to primary structures) when exposed to direct flames and brands. The under-deck flame exposure test is intended to determine the heat release rate (HRR) and degradation modes of deck or other horizontal boards when exposed to a burner flame simulating combustibles beneath a deck. The burning brand exposure test is intended to determine the degradation modes of deck or other horizontal boards when exposed to a burning brand on the upper surface.

    12-7A-4A.3 Referenced document.

    1. ASTM E108. Standard Test Methods for Fire Tests of Roof Coverings.
    2. California Building Code, Chapter 7A.

    12-7A-4A.4 Definitions.

    1. Deck boards. Horizontal members that constitute the exposed surface of the ancillary structure.
    2. Heat release rate. The net rate of energy release as measured by oxygen depletion calorimetry.

    12-7A-4A.5 Test assembly.

    1. Size. The overall size of the test deck shall be nominally 24 x 24 inches (610 x 610 mm) unless width variation of deck boards requires an increase in overall deck width (i.e., the direction of joists) in order to meet the overall dimensions. The length of individual deck boards shall be 24 inches (610 mm).
    2. Joists. The deck is supported by two nominal 2 x 6 Douglas-fir joists running perpendicular to the deck boards, and constructed with a 16-inch (406 mm) center-to-center spacing. A comparable species that may be more commonly used for structural framing of decks in a given region can be substituted for Douglas-fir.
    3. Deck board spacing and fastening. Edge-to-edge spacing and method of attachment shall conform to the manufacturer’s installation recommendations.
  • CWUIC § 5.3. High relevance — show source text

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    MATERIALS AND CONSTRUCTION METHODS FOR EXTERIOR WILDFIRE EXPOSURE

    5.3. Continued combustion. If penetration does not occur, continue observation for an additional 30 minutes or until all combustion has ceased.

    Note: An infrared thermometer has been found to be useful to detect the increase of temperature on the back side of the eaves and as an aid to identify the areas of potential combustion. 6. Observations. Note the time, location and nature of flame penetration.

    12-7A-3.9 Report. The report shall include a description of the eaves material, details of the construction of the eaves, moisture content of the framing and wood-based soffit elements as applicable, and point of flame penetration. Provide details on the time and reasons for early termination of the test.

    12-7A-3.10 Conditions of Acceptance. Should one of the three replicates fail to meet the Conditions of Acceptance, three additional tests may be run. All of the additional tests must meet the Conditions of Acceptance.

    1. Absence of flame penetration of the eaves or horizontal projection assembly at any time.
    2. Absence of structural failure of the eaves or horizontal projection subassembly at any time.
    3. Absence of sustained combustion of any kind at the conclusion of the 40-minute test.

    FIGURE 1 — EAVES TEST ASSEMBLY

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    MATERIALS AND CONSTRUCTION METHODS FOR EXTERIOR WILDFIRE EXPOSURE

    DECKING

    SFM STANDARD 12-7A-4

    12-7A-4.1 Application. The minimum design, construction and performance standards set forth herein for unloaded decks are those deemed necessary to establish conformance to the provisions of these regulations. Materials and assemblies that meet the performance criteria of this standard are acceptable for use as defined in California Building Standards Code.

    12-7A-4.2 Scope. This standard evaluates the performance of decks (or other horizontal ancillary structures in close proximity to primary structures) when exposed to direct flames and brands. The under-deck flame exposure test is intended to determine the heat release rate (HRR) and degradation modes of deck or other horizontal boards when exposed to a burner flame simulating combustibles beneath a deck. The burning brand exposure test is intended to determine the degradation modes of deck or other horizontal boards when exposed to a burning brand on the upper surface.

    12-7A-4.3 Referenced document.

    1. ASTM D4444, Test Methods for Use and Calibration of Hand-Held Moisture Meters.

    2. ASTM E108, Test Methods for Fire Tests of Roof Coverings.

    3. California Building Code, Chapter 7A.

    4. UL 790, Standard Test Methods for Fire Tests of Roof Coverings.

    12-7A-4.4 Definitions.

    1. Deck boards. Horizontal members that constitute the exposed surface of the ancillary structure.
    2. Deck surface area. The test specimen area defined by the overall specimen length and width after assembly.
    3. Heat release rate. The net rate of energy release as measured by oxygen depletion calorimetry.

    **12-7A-4.5 Test assembly.

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

    12-7A-4.8 PART B. Burning brand exposure.

    12-7A-4.8.1 Equipment.

    1. Wind tunnel. The wind tunnel shall have the capability of providing 12 mph (5.4 m/s) airflow over the deck assembly.
    2. Anemometer. Device for measuring airflow across the deck.
    3. Burner. Gas-fueled burner for brand ignition.

    12-7A-4.8.2 Test system preparation. See Figure 2. The ASTM E108 “A” brand roof test apparatus is to be used, with the following modifications:

    1. Deck support. The deck shall be supported horizontally with the center 60 inches (150 mm) from the front opening of the wind tunnel and the joists parallel to the airflow and resting on two transverse metal supports. The top surfaces of these supports, no more than 3 inches (75 mm) wide, are at the same height as the floor of the wind tunnel.
    2. Fragments. Burning fragments shall be free to fall to the floor of the room.

    12-7A-4.8.3 Conduct of tests.

    1. Number of tests. Conduct the test on three replicate assemblies.
    2. Moisture content. Measure the moisture content of the wooden members of the assembly using a moisture meter (ASTM D4444).
    3. Procedure. Adhere to ASTM E108 “Standard Test Methods for Fire Tests of Roof Coverings” (burning brand test, “A” brand), with apparatus modified as described above in “Test system preparation” and the following procedure: 3.1. The air velocity shall be calibrated using the 60-inch (1.5 m) framework spacing, with a smooth noncombustible calibration deck at a 5-inch (127 mm) per 12-inch (305 mm) horizontal incline positioned 60 inches (1.5 m) from the front opening of the wind tunnel. All other measurement details shall be followed as specified in Sections 4.4.2, 4.4.3 and 4.4.4 of ASTM E108. Although ASTM E108 specifies calibration to be conducted with the 33-inch (840-mm) framework spacing used for the intermittent flame test set up, tests have shown that at the nominal 12 mph

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    MATERIALS AND CONSTRUCTION METHODS FOR EXTERIOR WILDFIRE EXPOSURE

    setting, there was not difference in measured velocity between the 33- and 60-inch (838 mm and 1524 mm) framework spacing. 3.2. Mount the test specimen at a zero horizontal incline positioned 60 inches (1.5 m) from the front opening of the wind tunnel.

    3.3. Ignite the “A” brands as specified in Section 9.4 of ASTM E108 as reprinted here:

    1. Each 12- x 12-inch (300 x 300 mm) face for 30 seconds.
    2. Each 2.25- x 12-inch (57 x 300 mm) edge for 45 seconds.
    3. Each 12- x 12-inch (300 x 300 mm) face again for 30 seconds. 3.4. Center the burning brand laterally on the deck with the front edge 2.5 inches (64 mm) from the entering air edge of the deck.
  • CWUIC § 1.2 High relevance — show source text
    1. Ledger board. A 4-foot-long (1.2 m) simulated 2 x 6 ledger board shall be constructed of layers of ceramic fiber board (or other noncombustible panel product) and attached to the wall at a height slightly below the overhang of the rear deck board of the test deck.

    12-7A-4.7.3 Conduct of tests.

    1. Airflow. The test shall be conducted under conditions of ambient airflow.

    2. Number of tests. Conduct the test on three replicate assemblies.

    3. Burner output verification. Without a deck in the apparatus, set the output of the burner to 80 ± 4 kW. Conduct a verification run of 3 minutes to ensure the heat release rate, and then turn off the burner.

    4. Measurement of heat release rate. HRR is measured during the tests with a properly calibrated oxygen depletion calorimeter. Since HRR is typically a post-test analysis, this criterion for Acceptance may be determined at the end of the test.

    5. Burner positioning. Center the burner directly under the middle deck board, midway between the joists. The distance from the top of the burner to the bottom of the deck boards shall be 27 inches (690 mm).

    6. Moisture content. Measure the moisture content of the wooden members of the assembly using a moisture meter (ASTM D4444).

    7. Procedure.

    7.1. Ignition. Ignite the burner, controlling for a constant 80 ± 4 kW output. 7.2. Flame exposure. Continue the exposure for a 3-minute period. Extinguish the burner.

    7.3. Continued combustion. Continue observation for an additional 40 minutes or until all combustion has ceased.

    1. Observations. Note physical changes of the deck boards during the test, including structural failure of any deck board, location of flaming and glowing ignition, and loss of material (i.e., flaming drops of particles falling from the deck). It is desirable to capture the entire test with a video recorder to allow review of the details of performance.

    12-7A-4.7.4 Report. The report shall include a description of the deck board material and the time of any degradation (effective net peak heat release rate, structural failure, flaming drops or particles falling from the deck) during the test.

    1. Calculated rate of heat release. The effective net peak heat release rate (HRR) shall be calculated as follows: 1.1. During the first 5 minutes of the test (the 3 minutes during which the ignition source burner is operating and the immediately following 2 minutes) the effective net peak HRR of the test assembly shall be reported as: effective net peak HRR = (peak heat release rate – 80 kW) / (deck surface area). 1.2. During the remaining test duration the effective net peak heat release rate of the test assembly shall be reported as: effective net peak HRR = (peak heat release rate) / (deck surface area).
  • CWUIC § 12-7 High relevance — show source text

    DECKING

    SFM STANDARD 12-7A-4

    12-7A-4.1 Application. The minimum design, construction and performance standards set forth herein for unloaded decks are those deemed necessary to establish conformance to the provisions of these regulations. Materials and assemblies that meet the performance criteria of this standard are acceptable for use as defined in California Building Standards Code.

    12-7A-4.2 Scope. This standard evaluates the performance of decks (or other horizontal ancillary structures in close proximity to primary structures) when exposed to direct flames and brands. The under-deck flame exposure test is intended to determine the heat release rate (HRR) and degradation modes of deck or other horizontal boards when exposed to a burner flame simulating combustibles beneath a deck. The burning brand exposure test is intended to determine the degradation modes of deck or other horizontal boards when exposed to a burning brand on the upper surface.

    12-7A-4.3 Referenced document.

    1. ASTM D4444, Test Methods for Use and Calibration of Hand-Held Moisture Meters.

    2. ASTM E108, Test Methods for Fire Tests of Roof Coverings.

    3. California Building Code, Chapter 7A.

    4. UL 790, Standard Test Methods for Fire Tests of Roof Coverings.

    12-7A-4.4 Definitions.

    1. Deck boards. Horizontal members that constitute the exposed surface of the ancillary structure.
    2. Deck surface area. The test specimen area defined by the overall specimen length and width after assembly.
    3. Heat release rate. The net rate of energy release as measured by oxygen depletion calorimetry.

    12-7A-4.5 Test assembly.

    1. Size. The overall size of the test deck shall be nominally 24 x 24 inches (610 x 610 mm) unless width variation of deck boards requires an increase in overall deck width (i.e., the direction of joists) in order to meet the overall dimensions. The length of individual deck boards shall be 24 inches (610 mm).
    2. Joists. The deck is supported by two nominal 2 x 6 Douglas-fir joists running perpendicular to the deck boards, and constructed with a 16-inch (406 mm) center-to-center spacing. A comparable species that may be more commonly used for structural framing of decks in a given region can be substituted for Douglas-fir.
    3. Deck board spacing and fastening. Edge-to-edge spacing and method of attachment shall conform to the manufacturer’s installation recommendations. The front deck board shall be flush with the ends of the joists, and the rear deck board shall overhang the end of the joists by 1 inch (25 mm). 3.1. In the absence of recommended installation guidance, the edge-to-edge spacing shall be [3] / 16 inch (5 mm) with boards mechanically attached to the joists using deck screws. 3.2. If nominal 6-inch-wide (152 mm) deck boards are used, a total of 5 boards shall be used for each deck. Changing the board width could change the number of deck boards.

    12-7A-4.6 Materials.

  • CWUIC § 503.2.2 Medium relevance — show source text

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    SPECIAL BUILDING CONSTRUCTION REGULATIONS

    503.2.2 Fire-retardant-treated wood. Fire-retardant-treated wood shall be identified for exterior use and shall meet the requirements of Section 2303.2 of the California Building Code .

    503.2.3 Fire-retardant-treated wood roof coverings. Roof assemblies containing fire-retardant-treated wood shingles and shakes shall comply with the requirements of Section 1505.6 of the California Building Code and shall be classified as Class A roof assemblies as required in Section 1505.2 of the California Building Code .

    503.2.4 Other ignition-resistant building material. Material shall be tested on the front and back faces in accordance with the extended ASTM E84 or UL 723 test, for a total test period of 30 minutes, or with the ASTM E2768 test. The materials shall bear identification showing the fire test results. Panel products shall be tested with a ripped or cut longitudinal gap of [1] / 8 inch (3.2 mm). The materials, when tested in accordance with the test procedures set forth in ASTM E84 or UL 723 for a test period of 30 minutes, or with ASTM E2768, shall comply with Sections 503.2.4.1 through 503.2.4.3.

    Exception: Materials composed of a combustible core and a noncombustible exterior covering made from either aluminum at a minimum 0.019 inch (0.48 mm) thickness or corrosion-resistant steel at a minimum 0.0149 inch (0.38 mm) thickness shall not be required to be tested with a ripped or cut longitudinal gap.

    503.2.4.1 Flame spread. The material shall exhibit a flame spread index not exceeding 25.

    503.2.4.2 Flame front. The material shall exhibit a flame front that does not progress more than 10 feet 6 inches (3200 mm) beyond the centerline of the burner at any time during the test.

    503.2.4.3 Weathering. Ignition-resistant building materials shall maintain their performance in accordance with this section under conditions of use. The materials shall meet the performance requirements for weathering (including exposure to temperature, moisture and ultraviolet radiation) contained in Sections 503.2.4.3.1 through 503.2.4.3.3, as applicable to the materials and conditions of use.

    503.2.4.3.1 Evaluation requirements for weathering. Fire-retardant-treated wood, wood-plastic composite materials and plastic lumber materials shall be evaluated after weathering in accordance with Method A “Test Method for Accelerated Weathering of Fire-Retardant-Treated Wood for Fire Testing” in ASTM D2898.

    503.2.4.3.2 Wood-plastic composite materials. Wood-plastic composite materials shall also demonstrate acceptable fire performance after weathering by the following procedure: first testing in accordance with ASTM E1354 at an incident heat flux of 50 kW/m [2] in the horizontal orientation, then weathering in accordance with ASTM D7032 and then retesting in accordance with ASTM E1354 and exhibiting an increase of no more than 10 percent in peak rate of heat release when compared to the peak heat release rate of the nonweathered material.

  • CWUIC § 503.2.4.1 Medium relevance — show source text

    503.2.4.1 Flame spread. The material shall exhibit a flame spread index not exceeding 25.

    503.2.4.2 Flame front. The material shall exhibit a flame front that does not progress more than 10 feet 6 inches (3200 mm) beyond the centerline of the burner at any time during the test.

    503.2.4.3 Weathering. Ignition-resistant building materials shall maintain their performance in accordance with this section under conditions of use. The materials shall meet the performance requirements for weathering (including exposure to temperature, moisture and ultraviolet radiation) contained in Sections 503.2.4.3.1 through 503.2.4.3.3, as applicable to the materials and conditions of use.

    503.2.4.3.1 Evaluation requirements for weathering. Fire-retardant-treated wood, wood-plastic composite materials and plastic lumber materials shall be evaluated after weathering in accordance with Method A “Test Method for Accelerated Weathering of Fire-Retardant-Treated Wood for Fire Testing” in ASTM D2898.

    503.2.4.3.2 Wood-plastic composite materials. Wood-plastic composite materials shall also demonstrate acceptable fire performance after weathering by the following procedure: first testing in accordance with ASTM E1354 at an incident heat flux of 50 kW/m [2] in the horizontal orientation, then weathering in accordance with ASTM D7032 and then retesting in accordance with ASTM E1354 and exhibiting an increase of no more than 10 percent in peak rate of heat release when compared to the peak heat release rate of the nonweathered material.

    503.2.4.3.3 Plastic lumber materials. Plastic lumber materials shall also demonstrate acceptable fire performance after weathering by the following procedure: first testing in accordance with ASTM E1354 at an incident heat flux of 50 kW/m [2] in the horizontal orientation, then weathering in accordance with ASTM D6662 and then retesting in accordance with ASTM E1354 and exhibiting an increase of no more than 10 percent in peak rate of heat release when compared to the peak heat release rate of the nonweathered material.

    503.2.5 Surface treatment protection. Use of paints, coatings, stains or other surface treatments are not an approved method of protection as required in this chapter.

    503.3 Standards of quality. Building material, systems, assemblies and methods of construction shall be tested in accordance with the standards specified in Chapter 5.

    503.3.1 Qualification by testing. Material and material assemblies tested in accordance with the requirements of Section 503 shall be accepted for use when the results and conditions of those tests are met. Product evaluation testing of material and material assemblies shall be approved or listed by the State Fire Marshal or identified in a current report issued by an approved agency.

    503.3.2 Approved agency. Product evaluation testing shall be performed by an approved agency in accordance with Section 1703 of the California Building Code. The scope of accreditation for the approved agency shall include building product compliance with this code.

    503.3.3 Labeling. Material and material assemblies tested in accordance with the referenced standards shall bear an identification label showing the fire test results. That identification label shall be issued by a testing and/or inspecting agency approved by the State Fire Marshal.

    1. Identification mark of the approved testing and/or inspecting agency.

    2. Contact and identification information of the manufacturer.

  • 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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    7 REFERENCED STANDARDS

    User notes:

    About this chapter: This code contains numerous references to standards promulgated by other organizations that are used to provide requirements for materials and methods of construction. This chapter contains a comprehensive list of all standards that are referenced in this code. These standards, in essence, are part of this code to the extent of the reference to the standard.

    This chapter lists the standards that are referenced in various sections of this document. The standards are listed herein by the promulgating agency of the standard, the standard identification, the effective date and title, and the section or sections of this document that reference the standard.

    AASHTO American Association of State and Highway Transportation Officials, 444 North Capitol Street, NW, Suite 249, Washington, DC 20001

    HB-17—2002: Standard Specifications for Highway Bridges, 17th Edition, 2002

    403.1.8, 1273.10

    ASTM ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959

    D638—2022: Standard Test Method for Tensile Properties of Plastics

    504.9.1

    D2898—10(2017): Standard Practice for Accelerated Weathering of Fire-Retardant-Treated Wood for Fire Testing

    503.2.4.3.1

    D3909/D3909M— 2022 : Standard Specification for Asphalt Roll Roofing (Glass Felt) Surfaced With Mineral Granules

    504.2.1.1, 504.2.2

    D6662—22: Standard Specification for Polyolefin-Based Plastic Lumber Decking Boards

    503.2.4.3.3

    D7032—21: Standard Specification for Establishing Performance Ratings for Wood-Plastic Composite and Plastic Lumber Deck Boards, Stair Treads, Guards, and Handrails

    503.2.4.3.2

    E84— 2023d : Standard Test Method for Surface Burning Characteristics of Building Materials

    202, 501.4.1, 503.2.4, 504.7.3.2, 504.7.3.3

    E108—20a: Standard Test Methods for Fire Tests of Roof Coverings

    504.2, 504.2.1.2, 504.11.6, G101.2.1

  • CWUIC § 2.2.2 Medium relevance — show source text

    R507.2.2.2 Flame spread index. Plastic composite deck boards, stair treads, guards, and handrails shall exhibit a flame spread index not exceeding 200 when tested in accordance with ASTM E84 or UL 723 with the test specimen remaining in place during the test.

    Exception: Plastic composites determined to be noncombustible.

    R507.2.2.3 Decay resistance. Plastic composite deck boards, stair treads, guards and handrails containing wood, cellulosic or other biodegradable materials shall be decay resistant in accordance with ASTM D7032.

    R507.2.2.4 Termite resistance. Where required by Section 305, plastic composite deck boards, stair treads, guards and handrails containing wood, cellulosic or other biodegradable materials shall be termite resistant in accordance with ASTM D7032.

    R507.2.2.5 Installation of plastic composites. Plastic composite deck boards, stair treads, guards and handrails shall be installed in accordance with this code and the manufacturer’s instructions.

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    FLOORS

    R507.2.3 Fasteners and connectors. Metal fasteners and connectors used for all decks shall be in accordance with Section R304.3 and Table R507.2.3. Holes for through bolts shall be drilled to a diameter of [1] / 32 inch to [1] / 16 inch larger than the bolt diameter. Connectors shall be installed in accordance with the manufacturer’s approved instructions.

    TABLE R507.2.3—FASTENER AND CONNECTOR SPECIFICATIONS FOR DECKSa, b Col2 Col3 Col4
    ITEM MATERIAL MINIMUM FINISH/COATING ** ALTERNATE FINISH/COATINGc**
    Nails and glulam rivets In accordance with ASTM F1667 Hot-dipped galvanized per ASTM
    A153, Class D or ASTM A641 Class 3S
    for3/8-inch diameter and less    		 Stainless steel, silicon bronze or
    copper
    Bolts In accordance with ASTM
    A307 (bolts), ASTM A563 (nuts),
    ASTM F844 (washers)    		 Hot-dipped galvanized per ASTM
    A153, Class C (Class D for3/8-inch
    diameter and less) or mechanically
    galvanized per ASTM B695, Class 55 or
    410 stainless steel    		 Stainless steel, silicon bronze or
    copper
    Lag screws
    (including nuts and washers)    		 Lag screws
    (including nuts and washers)    		 Lag screws
    (including nuts and washers)    		 Lag screws
    (including nuts and washers)
    Metal connectors Per manufacturer’s specification ASTM A653 type G185 zinc-coated
    galvanized steel or post hot-dipped
    galvanized per ASTM A123 providing a
    minimum average coating weight of
    2.0 oz./ft2 (total both sides)    		 Stainless steel
    For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm.
    a. Equivalent materials, coatings and finishes shall be permitted.
    b. Fasteners and connectors exposed to salt water or located within 300 feet of a salt water shoreline shall be stainless steel.
    c.
  • CWUIC § 2611.1 Medium relevance — show source text

    SECTION 2611—LIGHT-TRANSMITTING PLASTIC INTERIOR SIGNS

    2611.1 General. Light-transmitting plastic interior signs shall be limited as specified in Sections 2606 and 2611.2 through 2611.4.

    Exception: Light-transmitting plastic interior wall signs in covered and open mall buildings shall comply with Section 402.6.4. 2611.2 Maximum area. The aggregate area of all light-transmitting plastics shall not exceed 24 square feet (2.23 m [2] ).

    Exception: In buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1, the aggregate area of light-transmitting plastics shall not exceed 100 square feet (9.29 m [2] ), provided that all plastics are Class CC1 in accordance with Section 2606.4.

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    PLASTIC

    2611.3 Separation. Signs exceeding the aggregate area of Section 2611.2 shall be separated from each other by not less than 4 feet (1219 mm) horizontally and 8 feet (2438 mm) vertically.

    2611.4 Encasement. Backs of wall-mounted signs and non-illuminated portions of all signs regulated by this section shall be fully encased in metal.

    SECTION 2612—PLASTIC COMPOSITE DECKING

    [BS] 2612.1 General. Plastic composites shall consist of either wood/plastic composites or plastic lumber. Plastic composites shall comply with the provisions of this code and with the additional requirements of Section 2612.

    [BS] 2612.2 Labeling. Plastic composite deck boards and stair treads, or their packaging, shall bear a label that indicates compliance with ASTM D7032 and includes the allowable load and maximum allowable span determined in accordance with ASTM D7032. Plastic composite handrails and guards, or their packaging, shall bear a label that indicates compliance with ASTM D7032 and includes the maximum allowable span determined in accordance with ASTM D7032.

    [BF] 2612.3 Flame spread index. Plastic composite deck boards, stair treads, handrails and guards shall exhibit a flame spread index not exceeding 200 when tested in accordance with ASTM E84 or UL 723 with the test specimen remaining in place during the

    test.

    Exception: Materials determined to be noncombustible in accordance with Section 703.3.

    [BS] 2612.4 Termite and decay resistance. Where required by Section 2304.12, plastic composite deck boards, stair treads, handrails and guards containing wood, cellulosic or any other biodegradable materials shall be termite and decay resistant as determined in accordance with ASTM D7032.

    [BS] 2612.5 Construction requirements. Plastic composites meeting the requirements of Section 2612 shall be permitted to be used as exterior deck boards, stair treads, handrails and guards where combustible construction is permitted.

    [BS] 2612.5.1 Span rating. Plastic composites used as exterior deck boards shall have a span rating determined in accordance with ASTM D7032.

    [BS] 2612.6 Plastic composite deck boards, stair treads, handrails and guards. Plastic composite deck boards, stair treads, handrails and guards shall be installed in accordance with this code and the manufacturer’s instructions.

  • CWUIC § 602.4.1 Medium relevance — show source text

    602.4.1 Type IV-A. Building elements in Type IV-A construction shall be protected in accordance with Sections 602.4.1.1 through 602.4.1.6. The required fire-resistance rating of noncombustible elements and protected mass timber elements shall be determined in accordance with Section 703.2.

    602.4.1.1 Exterior protection. The outside face of exterior walls of mass timber construction shall be protected with noncombustible protection with a minimum assigned time of 40 minutes, as specified in Table 722.7.1(1). Components of the exterior wall covering shall be of noncombustible material except water-resistive barriers having a peak heat release rate of less than 150kW/m [2], a total heat release of less than 20 MJ/m [2] and an effective heat of combustion of less than 18MJ/kg as determined in accordance with ASTM E1354 and having a flame spread index of 25 or less and a smoke-developed index of 450 or less as

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    TYPES OF CONSTRUCTION

    determined in accordance with ASTM E84 or UL 723. The ASTM E1354 test shall be conducted on specimens at the thickness intended for use, in the horizontal orientation and at an incident radiant heat flux of 50 kW/m [2] .

    602.4.1.2 Interior protection. Interior faces of all mass timber elements, including the inside faces of exterior mass timber walls and mass timber roofs, shall be protected with materials complying with Section 703.3.

    602.4.1.2.1 Protection time. Noncombustible protection shall contribute a time equal to or greater than times assigned in Table 722.7.1(1), but not less than 80 minutes. The use of materials and their respective protection contributions specified in Table 722.7.1(2) shall be permitted to be used for compliance with Section 722.7.1.

    602.4.1.3 Floors. The floor assembly shall contain a noncombustible material not less than 1 inch (25 mm) in thickness above the mass timber. Floor finishes in accordance with Section 804 shall be permitted on top of the noncombustible material. The underside of floor assemblies shall be protected in accordance with Section 602.4.1.2.

    602.4.1.4 Roofs. The interior surfaces of roof assemblies shall be protected in accordance with Section 602.4.1.2. Roof coverings in accordance with Chapter 15 shall be permitted on the outside surface of the roof assembly.

    602.4.1.5 Concealed spaces. Concealed spaces shall not contain combustibles other than electrical, mechanical, fire protection, or plumbing materials and equipment permitted in plenums in accordance with the California Mechanical Code, and shall comply with all applicable provisions of Section 718. Combustible construction forming concealed spaces shall be protected in accordance with Section 602.4.1.2.

    602.4.1.6 Shafts. Shafts shall be permitted in accordance with Sections 713 and 718. Both the shaft side and room side of mass timber elements shall be protected in accordance with Section 602.4.1.2.

  • CWUIC § 602.4.1.2.1 Medium relevance — show source text

    602.4.1.2.1 Protection time. Noncombustible protection shall contribute a time equal to or greater than times assigned in Table 722.7.1(1), but not less than 80 minutes. The use of materials and their respective protection contributions specified in Table 722.7.1(2) shall be permitted to be used for compliance with Section 722.7.1.

    602.4.1.3 Floors. The floor assembly shall contain a noncombustible material not less than 1 inch (25 mm) in thickness above the mass timber. Floor finishes in accordance with Section 804 shall be permitted on top of the noncombustible material. The underside of floor assemblies shall be protected in accordance with Section 602.4.1.2.

    602.4.1.4 Roofs. The interior surfaces of roof assemblies shall be protected in accordance with Section 602.4.1.2. Roof coverings in accordance with Chapter 15 shall be permitted on the outside surface of the roof assembly.

    602.4.1.5 Concealed spaces. Concealed spaces shall not contain combustibles other than electrical, mechanical, fire protection, or plumbing materials and equipment permitted in plenums in accordance with the California Mechanical Code, and shall comply with all applicable provisions of Section 718. Combustible construction forming concealed spaces shall be protected in accordance with Section 602.4.1.2.

    602.4.1.6 Shafts. Shafts shall be permitted in accordance with Sections 713 and 718. Both the shaft side and room side of mass timber elements shall be protected in accordance with Section 602.4.1.2.

    602.4.2 Type IV-B. Building elements in Type IV-B construction shall be protected in accordance with Sections 602.4.2.1 through 602.4.2.6. The required fire-resistance rating of noncombustible elements or mass timber elements shall be determined in accordance with Section 703.2.

    602.4.2.1 Exterior protection. The outside face of exterior walls of mass timber construction shall be protected with noncombustible protection with a minimum assigned time of 40 minutes, as specified in Table 722.7.1(1). Components of the exterior wall covering shall be of noncombustible material except water-resistive barriers having a peak heat release rate of less than 150kW/m [2], a total heat release of less than 20 MJ/m [2] and an effective heat of combustion of less than 18MJ/kg as determined in accordance with ASTM E1354, and having a flame spread index of 25 or less and a smoke-developed index of 450 or less as determined in accordance with ASTM E84 or UL 723. The ASTM E1354 test shall be conducted on specimens at the thickness intended for use, in the horizontal orientation and at an incident radiant heat flux of 50 kW/m [2] .

    602.4.2.2 Interior protection. Interior faces of all mass timber elements, including the inside face of exterior mass timber walls and mass timber roofs, shall be protected, as required by this section, with materials complying with Section 703.3.

  • CWUIC § 2.1 Medium relevance — show source text

    R507.2 Materials. Materials used for the construction of decks shall comply with this section.

    R507.2.1 Wood materials. Wood structural members shall be protected from decay where required by Sections R304.1 and R304.1.2, and protected from termites where required by Section R305.1. Where design in accordance with Section R301 is provided, wood structural members shall be designed using the wet service factor defined in AWC NDS. Sawn lumber for joists, beams and posts shall be No. 2 or better. Cuts, notches and drilled holes of preservative-treated wood members shall be treated in accordance with Section R304.1.1.

    R507.2.1.1 Engineered wood products. Engineered wood products shall be in accordance with Section R502.

    R507.2.2 Plastic composite deck boards, stair treads, guards or handrails. Plastic composite exterior deck boards, stair treads, guards and handrails shall comply with the requirements of ASTM D7032 and this section.

    R507.2.2.1 Labeling. Plastic composite deck boards and stair treads, or their packaging, shall bear a label that indicates compliance with ASTM D7032 and includes the allowable load and maximum allowable span determined in accordance with ASTM D7032. Plastic or composite handrails and guards, or their packaging, shall bear a label that indicates compliance with ASTM D7032 and includes the maximum allowable span determined in accordance with ASTM D7032.

    R507.2.2.2 Flame spread index. Plastic composite deck boards, stair treads, guards, and handrails shall exhibit a flame spread index not exceeding 200 when tested in accordance with ASTM E84 or UL 723 with the test specimen remaining in place during the test.

    Exception: Plastic composites determined to be noncombustible.

    R507.2.2.3 Decay resistance. Plastic composite deck boards, stair treads, guards and handrails containing wood, cellulosic or other biodegradable materials shall be decay resistant in accordance with ASTM D7032.

    R507.2.2.4 Termite resistance. Where required by Section 305, plastic composite deck boards, stair treads, guards and handrails containing wood, cellulosic or other biodegradable materials shall be termite resistant in accordance with ASTM D7032.

    R507.2.2.5 Installation of plastic composites. Plastic composite deck boards, stair treads, guards and handrails shall be installed in accordance with this code and the manufacturer’s instructions.

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    FLOORS

    R507.2.3 Fasteners and connectors. Metal fasteners and connectors used for all decks shall be in accordance with Section R304.3 and Table R507.2.3. Holes for through bolts shall be drilled to a diameter of [1] / 32 inch to [1] / 16 inch larger than the bolt diameter. Connectors shall be installed in accordance with the manufacturer’s approved instructions.

    |TABLE R507.2.3—FASTENER AND CONNECTOR SPECIFICATIONS FOR DECKSa,

  • CWUIC § 2612.2 Medium relevance — show source text

    [BS] 2612.2 Labeling. Plastic composite deck boards and stair treads, or their packaging, shall bear a label that indicates compliance with ASTM D7032 and includes the allowable load and maximum allowable span determined in accordance with ASTM D7032. Plastic composite handrails and guards, or their packaging, shall bear a label that indicates compliance with ASTM D7032 and includes the maximum allowable span determined in accordance with ASTM D7032.

    [BF] 2612.3 Flame spread index. Plastic composite deck boards, stair treads, handrails and guards shall exhibit a flame spread index not exceeding 200 when tested in accordance with ASTM E84 or UL 723 with the test specimen remaining in place during the

    test.

    Exception: Materials determined to be noncombustible in accordance with Section 703.3.

    [BS] 2612.4 Termite and decay resistance. Where required by Section 2304.12, plastic composite deck boards, stair treads, handrails and guards containing wood, cellulosic or any other biodegradable materials shall be termite and decay resistant as determined in accordance with ASTM D7032.

    [BS] 2612.5 Construction requirements. Plastic composites meeting the requirements of Section 2612 shall be permitted to be used as exterior deck boards, stair treads, handrails and guards where combustible construction is permitted.

    [BS] 2612.5.1 Span rating. Plastic composites used as exterior deck boards shall have a span rating determined in accordance with ASTM D7032.

    [BS] 2612.6 Plastic composite deck boards, stair treads, handrails and guards. Plastic composite deck boards, stair treads, handrails and guards shall be installed in accordance with this code and the manufacturer’s instructions.

    SECTION 2613—FIBER-REINFORCED POLYMER

    2613.1 General. The provisions of this section shall govern the requirements and uses of fiber-reinforced polymer in and on buildings and structures.

    2613.2 Labeling and identification. Packages and containers of fiber-reinforced polymer and their components delivered to the job site shall bear the label of an approved agency showing the manufacturer’s name, product listing, product identification and information sufficient to determine that the end use will comply with the code requirements.

    2613.3 Interior finishes. Fiber-reinforced polymer used as interior finishes, decorative materials or trim shall comply with Chapter 8.

    2613.3.1 Foam plastic cores. Fiber-reinforced polymer used as interior finish and that contains foam plastic cores shall comply with Chapter 8 and this chapter.

    2613.4 Light-transmitting materials. Fiber-reinforced polymer used as light-transmitting materials shall comply with Sections 2606 through 2611 as required for the specific application.

    2613.5 Exterior use. Fiber-reinforced polymer shall be permitted to be installed on the exterior walls of buildings of any type of construction where such polymers meet the requirements of Section 2603.5. Fireblocking shall be installed in accordance with Section 718.

    Exceptions:

    1. Compliance with Section 2603.5 is not required where all of the following conditions are met: 1.1.
  • CWUIC § 0.125 Medium relevance — show source text

    Exception: Materials having a structural base of noncombustible material as determined in accordance with ASTM E136, or with ASTM E2652 using the acceptance criteria prescribed by ASTM E136, and a surfacing of not more than 0.125 inch (3.18 mm) in thick- ness having a flame spread index not greater than 50 when tested in accordance with ASTM E84 or UL 723 shall be acceptable as noncombustible.

    SECTION 502— RESERVED

    SECTION 503—IGNITION-RESISTANT CONSTRUCTION AND MATERIAL

    503.1 General. Buildings and structures hereafter constructed, modified or relocated into or within wildland-urban interface areas shall meet the construction requirements in accordance with Chapter 5 . Materials required to be ignition-resistant building materials shall comply with the requirements of Section 503.2.

    Exceptions:

    1. New accessory buildings and miscellaneous structures complying with Section 504.11. 2. Additions to and remodels of buildings originally constructed prior to July 1, 2008. 3. Group C occupancy special buildings conforming to the limitations specified in Section 450.4.1 of the California Building Code.

    503.2 Ignition-resistant building material. Ignition-resistant building materials shall be designed for exterior use and weather expo- sure and shall comply with any one of the requirements in Section 503.2.1 through 503.2.4.3.3 .

    503.2.1 Noncombustible material. Noncombustible material shall comply with the requirements in Section 501.4 .

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    SPECIAL BUILDING CONSTRUCTION REGULATIONS

    503.2.2 Fire-retardant-treated wood. Fire-retardant-treated wood shall be identified for exterior use and shall meet the requirements of Section 2303.2 of the California Building Code .

    503.2.3 Fire-retardant-treated wood roof coverings. Roof assemblies containing fire-retardant-treated wood shingles and shakes shall comply with the requirements of Section 1505.6 of the California Building Code and shall be classified as Class A roof assemblies as required in Section 1505.2 of the California Building Code .

    503.2.4 Other ignition-resistant building material. Material shall be tested on the front and back faces in accordance with the extended ASTM E84 or UL 723 test, for a total test period of 30 minutes, or with the ASTM E2768 test. The materials shall bear identification showing the fire test results. Panel products shall be tested with a ripped or cut longitudinal gap of [1] / 8 inch (3.2 mm). The materials, when tested in accordance with the test procedures set forth in ASTM E84 or UL 723 for a test period of 30 minutes, or with ASTM E2768, shall comply with Sections 503.2.4.1 through 503.2.4.3.

    Exception: Materials composed of a combustible core and a noncombustible exterior covering made from either aluminum at a minimum 0.019 inch (0.48 mm) thickness or corrosion-resistant steel at a minimum 0.0149 inch (0.38 mm) thickness shall not be required to be tested with a ripped or cut longitudinal gap.

  • CWUIC § 4909.1 Medium relevance — show source text

    1_|Subdivision
    identification|Y|||4909.1|||||| |611.2|Fire safety
    recommendations|Y|||4909.2|||||| |611.3|Implementation|Y|||4909.3|||||| |611.4|Re-survey|Y|||4909.4|||||| |612|General plan safety
    element|Y|||4910|||||| |612.1|General|Y|||4901.1|||||| |612.2|Submission to the
    Board of Forestry and
    Fire protection and
    local fire agencies|Y|||4910.2|||||| |612.3|Review by the Board
    of Forestry and Fire
    Protection and local
    fire agencies|Y|||4910.3|||||| |612.4|Adoption of the Safety
    element|Y|||4910.4|||||| |Chapter 7|Referenced standards|Referenced standards|Referenced standards|Referenced standards|Referenced standards|Referenced standards|Referenced standards|Referenced standards|Referenced standards|Referenced standards| ||AASHTO HB—2022|Y|||Ch 80|||||| ||ASTM D638|Y||708A.4||||||| ||ASTM D2898—
    2010(2017)|Y||||||||| ||ASTM D3909/
    D3909m—2022|Y||||||||| ||ASTM D6662—2022|Y||||||||| ||ASTM D7032—2021|Y||||||||| ||ASTM E84—2023d|Y||||||||| ||ASTM E108—2020a|Y||||||||| ||ASTM E119—2022|Y||||||||| ||ASTM E136—2024a|Y||||||||| ||ASTM E1354—2023|Y||||||||| ||ASTM E2632—2020|Y||||||||| ||ASTM E2707—2022|Y||707A.4.1||||||| ||ASTM E2726/E2726M—
    2012a(2017)|Y||709A.4.2||||||| ||ASTM E2768—2011
    (2018)|Y||||||||| ||ASTM E2886/
    E2886M—2020|Y||||||||| ||ASTM E2957—2017|Y||||||||| ||ASTM G155—2021|Y||708A.

Frequently asked questions

What if a decking product only has an E84 report?

E84 alone may satisfy certain limited exceptions (for example the exception in § 504.7.3.2 that allows an attached wall material flexibility if decking meets E84 Class B), but for the primary performance pathway E2632 and E2726 (and compliance with § 503.2.4) are required. § 504.7.3.3.

How many test specimens are required?

A minimum of three replicate test specimens for each ASTM test (E2632 and E2726); if one of the three fails, three additional tests must be run and all three additional tests must pass. § 504.7.3.3.1 / .3.2.

What is the HRR pass/fail threshold for the under‑deck test?

The effective net peak HRR must be ≤ 25 kW/ft² (269 kW/m²) (normalized by deck surface area and with the initial 80 kW burner subtracted during the first 3 minutes per SFM reporting). § 504.7.3.3.1.

Do plastic or composite decks need weathering tests?

Yes — wood‑plastic composite boards and plastic lumber require weathering evaluation (D7032 or D6662 respectively) and E1354 retesting; the post‑weathering peak HRR increase must be ≤ 10% per § 503.2.4.3.2/.3.3.

Who must label the tested product and what should the label show?

Products tested under the referenced standards must bear identification showing the fire test results and be reported by an approved testing/inspecting agency; labeling and approved‑agency requirements are in § 503.3.3.

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