CWUIC · California Wildland-Urban Interface Code
Where are SFM 12‑7A decking standards and alternate deck test methods referenced?
The CWUIC permits decking to comply by several test paths; importantly, **§ 504.7.3.2** explicitly references the State Fire Marshal’s decking standards **12‑7A‑4** and **12‑7A‑4A**, and **§ 504.7.3.3** spells out the test performance criteria (peak heat release, no sustained flaming, no burning falling particles). If you choose the SFM path you must follow the SFM test setups (80 kW under‑deck burner, 3‑minute exposure; burning‑brand 12 mph wind, 40 minutes; specimen size and joist framing; three replicates and acceptance rules) and submit the SFM test report as proof of compliance.
Last reviewed: July 6, 2026
What the code requires — plain English
The CWUIC says the walking surface of decks, porches, balconies and stairs must meet one of several listed performance paths — including materials tested to the State Fire Marshal SFM 12‑7A‑4 (Decking) or SFM 12‑7A‑4A (Decking Alternate Method A) standards — and it ties those paths to the performance tests required by § 504.7.3.2. The specific test performance criteria (peak heat release, no sustained flaming/glowing, no burning falling particles, plus ASTM/UL surface‑burning requirements) are set out in § 504.7.3.3 and by the SFM test methods described in 12‑7A‑4 and 12‑7A‑4A.
Deck walking surfaces must meet one of the listed performance paths in § 504.7.3.2, and materials relying on State Fire Marshal decking tests must meet the SFM acceptance criteria in 12‑7A‑4 (and/or 12‑7A‑4A) as referenced by § 504.7.3.2 and § 504.7.3.3.
Requirements in detail
Key code references (first mentions bolded)
- § 504.7.3.2 — Lists acceptable decking material paths, including SFM standards 12‑7A‑4 and 12‑7A‑4A.
- § 504.7.3.3 — Sets the test standards and conditions of acceptance for materials that use ASTM/UL testing (including the ASTM criteria that pair with SFM references).
- SFM 12‑7A‑4 — Two‑part decking test: Part A = heat release rate (under‑deck flame) and Part B = burning‑brand (upper surface) test. Used where the CWUIC references SFM 12‑7A‑4.
- SFM 12‑7A‑4A — Alternate Method A: a heat‑release (under‑deck) deck assembly combustion test (80 kW burner, 3 min) with post‑exposure observation; accepted as a performance path in § 504.7.3.2.
What § 504.7.3.2 allows (decision list)
- Material that meets the performance requirements of § 504.7.3.3 when tested to ASTM E2632 and ASTM E2726.
- Ignition‑resistant building material that meets § 503.2.4.
- Material that meets SFM 12‑7A‑4 and § 503.2.4.
- Fire‑retardant‑treated wood labeled for exterior use meeting CBC Section 2303.2.
- Noncombustible material.
- Material meeting SFM 12‑7A‑4A provided any attached exterior wall covering is noncombustible or ignition‑resistant (with a stated exception allowing other wall materials if the decking itself meets ASTM E84 / UL 723 Class B).
- Material meeting other referenced ASTM paths (ASTM E2632 with wall‑covering conditions) — see § 504.7.3.2 for full list.
Performance criteria and test thresholds (from § 504.7.3.3 and SFM rules)
Use the table below to summarize the decision‑relevant dimensions/values.
| Decision item | Value / threshold | Code Reference |
|---|---|---|
| ASTM E2632 peak heat release rate | ≤ 25 kW/ft² (269 kW/m²) (peak) | § 504.7.3.3.1(1) |
| ASTM E2632 other acceptance items | No sustained flaming/glowing at 40‑min end; no falling burning particles that reach burner/floor | § 504.7.3.3.1(2–3) |
| SFM 12‑7A‑4 — Part A (under‑deck flame) burner output | 80 ± 4 kW for 3 minutes | 12‑7A‑4 referenced by § 504.7.3.2 & SFM text |
| SFM 12‑7A‑4 — Part B (burning brand) exposure | 12 mph wind, 40 minutes, 2.2 lb (1 kg) “Class A” 12"×12"×2.25" brand | 12‑7A‑4 referenced by § 504.7.3.2 |
| SFM 12‑7A‑4A specimen size | 24 × 24 in (610 × 610 mm) nominal | 12‑7A‑4A.5 |
| SFM 12‑7A‑4A joist framing | Two nominal 2×6 joists, 16‑in c‑c | 12‑7A‑4A.5(2) |
| 12‑7A‑4A burner‑to‑deck distance | Burner top to bottom of deck 27 in (690 mm) | 12‑7A‑4A.7.3(5) |
| Number of test replicates | Three specimens; if one fails, run three more — all three must pass | 12‑7A‑4A.7.3(2) and acceptance rules 12‑7A‑4.8.5 |
| Conditions of acceptance (SFM) | Absence of sustained flaming/glowing at end of observation; no burning particles reaching burner/floor | 12‑7A‑4.8.5 |
| Moisture conditioning | Material conditioned to constant weight or minimum 30 days at 73 ± 4°F / 50 ± 5% RH; joist moisture 8–10% | 12‑7A‑4A.6 |
(See the cited SFM sections for full test setups, instrumentation and reporting requirements.)
How the ASTM/UL and SFM paths interact
- CWUIC requires that materials tested under ASTM E2632/E2726 (the ASTM performance path) must also meet ASTM E84 / UL 723 surface burning where called for by § 504.7.3.3 — the SFM paths (12‑7A‑4 / 12‑7A‑4A) are alternative, SFM‑specified assembly tests that the code accepts when performed and reported per the SFM procedures.
Exceptions & special cases
- Exception in § 504.7.3.2: if the decking surface itself complies with ASTM E84 / UL 723 Class B, the attached wall material may be of the chapter‑compliant material rather than noncombustible/ignition‑resistant (i.e., the wall exception). § 504.7.3.2 explicitly allows this limited exception.
- The SFM standard test procedures specify termination criteria: tests stop immediately if runaway flaming or structural failure occurs; such early terminations count as failure unless otherwise documented in the SFM report. See 12‑7A‑4A.7.3(7.3) and reporting/acceptance sections.
Common mistakes
- Treating SFM documents as optional: the code explicitly references SFM 12‑7A‑4 and 12‑7A‑4A as acceptable test methods in § 504.7.3.2; if you rely on those paths you must follow the SFM procedures and conditions of acceptance.
- Ignoring the ASTM E84 / UL 723 surface‑burning requirement: some ASTM E2632 test results must still satisfy surface burning-index criteria in § 504.7.3.3 (see cross reference to Section 503.2.4).
- Failing to run the specified number of replicates or to condition materials (moisture/temperature) before testing — SFM methods require three replicates and strict conditioning.
Worked example
Scenario: A manufacturer wants to certify a new composite deck board for use as an exposed walking surface in a CWUIC area.
- Path selection: The manufacturer chooses the SFM alternate method path, SFM 12‑7A‑4A (accepted by § 504.7.3.2).
- Test setup per SFM 12‑7A‑4A:
- Build a 24 × 24 in test deck with five 6‑in nominal boards (if using 6‑in boards) supported on two 2×6 joists at 16‑in c‑c.
- Condition materials to 73 ± 4°F, 50 ± 5% RH or until constant weight; ensure joist moisture 8–10%.
- Verify burner output at 80 ± 4 kW, position burner 27 in below deck bottom, run burner for 3 minutes, then observe for 40 minutes.
- Acceptance criteria: Run three replicates. To pass, all tests (or if one failed then three additional all passing) must show no sustained flaming/glowing at the end of the observation and no burning particles falling to burner/floor. If these conditions are met, the material can be listed as complying with the SFM path permitted under § 504.7.3.2.
Related provisions (within CWUIC)
- § 504.7.3.2 — Decking surfaces permitted paths (SFM references).
- § 504.7.3.3 — Test performance requirements for ASTM paths (peak HRR, 40‑min observation conditions).
- SFM 12‑7A‑4 — Decking two‑part test (Part A HRR, Part B burning‑brand) — referenced by § 504.7.3.2.
- SFM 12‑7A‑4A — Decking Alternate Method A (under‑deck HRR test) — referenced by § 504.7.3.2.
- ASTM and UL standards cross‑referenced by Chapter 7 listed test methods (e.g., ASTM E2632, ASTM E2726, ASTM E108, ASTM E84 / UL 723).
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 § 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:
- Absence of sustained flaming or glowing combustion of any kind at the conclusion of the 40-minute observation period.
- 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
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.
- ASTM E108. Standard Test Methods for Fire Tests of Roof Coverings.
- California Building Code, Chapter 7A.
12-7A-4A.4 Definitions.
- Deck boards. Horizontal members that constitute the exposed surface of the ancillary structure.
- Heat release rate. The net rate of energy release as measured by oxygen depletion calorimetry.
12-7A-4A.5 Test assembly.
- 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).
- 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.
- Deck board spacing and fastening. Edge-to-edge spacing and method of attachment shall conform to the manufacturer’s installation recommendations.
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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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.
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.
- Absence of flame penetration of the eaves or horizontal projection assembly at any time.
- Absence of structural failure of the eaves or horizontal projection subassembly at any time.
- 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.
ASTM D4444, Test Methods for Use and Calibration of Hand-Held Moisture Meters.
ASTM E108, Test Methods for Fire Tests of Roof Coverings.
California Building Code, Chapter 7A.
UL 790, Standard Test Methods for Fire Tests of Roof Coverings.
12-7A-4.4 Definitions.
- Deck boards. Horizontal members that constitute the exposed surface of the ancillary structure.
- Deck surface area. The test specimen area defined by the overall specimen length and width after assembly.
- 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
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.
ASTM D4444, Test Methods for Use and Calibration of Hand-Held Moisture Meters.
ASTM E108, Test Methods for Fire Tests of Roof Coverings.
California Building Code, Chapter 7A.
UL 790, Standard Test Methods for Fire Tests of Roof Coverings.
12-7A-4.4 Definitions.
- Deck boards. Horizontal members that constitute the exposed surface of the ancillary structure.
- Deck surface area. The test specimen area defined by the overall specimen length and width after assembly.
- Heat release rate. The net rate of energy release as measured by oxygen depletion calorimetry.
12-7A-4.5 Test assembly.
- 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).
- 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.
- 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 § 2603.10 High relevance — show source text
2603.10
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REFERENCED STANDARDS
SDI Steel Deck Institute, 2661 Clearview Road #3, Allison Park, PA 15101
ANSI/SDI QA/QC—2022: Standard for Quality Control and Quality Assurance for Installation of Steel Deck
1705.2.3
ANSI/SDI SD—2022: Standard for Steel Deck
2208.1
SFM State of California, Department of Forestry and Fire Protection, Office of the State Fire Marshal, P.O. Box 944246, Sacramento, CA 94246-2460
12-3: Releasing Systems for Security Bars in Dwellings
1029.4
12-7-3: Fire-testing Furnaces
NA
12-7A-1: Exterior Wall Siding and Sheathing
703A.7, 707A.2
12-7A-2: Exterior Window
703A.7, 708A.2.1
12-7A-3: Under Eave
703A.7, 707A.8
12-7A-4: Decking:
703A.7, 709A.3
12-7A-4A: Decking Alternate Method A
703A.7, 709A.3
12-7A-5: Ignition Resistant Building Material
703A.7, 709A.3
12-8-100: Room Fire Tests for Wall and Ceiling Materials
NA
12-10-1: Power Operated Exit Doors
NA
12-10-2: Single Point Latching or Locking Devices
NA
12-10-3: Emergency Exit and Panic Hardware
NA
(The Office of the State Fire Marshal standards referred to above are found in the California Code of Regulations, Title 24, Part 12.):
SJI Steel Joist Institute, 140 Evans Street, Suite 203, Florence, SC 29501
SJI 100—2020: Standard Specification for K-Series, LH-Series, and DLH-Series Open Web Steel Joists and for Joist Girders
1604.3.3, 2207.1, 2207.2, 2207.3, 2207.4, 2207.5
SJI 200—2015: Standard Specification for CJ-Series Composite Steel Joists
1604.3.3, 2207.1, 2207.2, 2207.3, 2207.4, 2207.5
SPRI Single-Ply Roofing Industry, 465 Waverly Oaks Road, Suite 421, Waltham, MA 02452
ANSI/SPRI GT-1—2022: Test Standard for External Gutter Systems
1504.6.1, 1511.7.6.1
ANSI/SPRI RP-4—2019: Wind Design Standard for Ballasted Single-ply Roofing Systems
1504.5
ANSI/SPRI VF-1—2021: External Fire Design Standard for Vegetative Roofs
CWUIC § 12-7 High relevance — show source text
12-7A-4A.7.2 Test system preparation. See 12-7A-4 Figure No. 1.
- Deck support assembly. Assembly that holds the test deck over the burner.
- Baffle panels and joist support. Horizontal metal plates to support the deck joists along their full length, and also to confine burner flames to the underside of the deck boards located between the support joists.
- Back wall. Ceramic fiber board or another noncombustible panel product for the back wall material. Total height of the back wall is 8 feet (2.4 m).
- 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.
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MATERIALS AND CONSTRUCTION METHODS FOR EXTERIOR WILDFIRE EXPOSURE
12-7A-4A.7.3 Conduct of tests.
Airflow. The test is conducted under conditions of ambient airflow.
Number of tests. Conduct the test on three replicate assemblies.
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.
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.
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).
Moisture content. Measure the moisture content of the wooden members of the assembly using a moisture meter (ASTM D4444).
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. The test shall be terminated immediately if flaming combustion accelerates uncontrollably (runaway combustion) or structural failure of any deck board occurs. 8. 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-4A.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) during the test.
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:
- Each 12- x 12-inch (300 x 300 mm) face for 30 seconds.
- Each 2.25- x 12-inch (57 x 300 mm) edge for 45 seconds.
- 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:
- Absence of sustained flaming or glowing combustion of any kind at the conclusion of the 40-minute observation period.
- 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 § 12.2 High relevance — show source text
R506.2
SBCA Structural Building Components Association 6300 Enterprise Lane Madison, WI 53719
BCSI—2018: Building Component Safety Information—Guide to Good Practice for Handling, Installing, Restraining & Bracing of Metal Plate Connected Wood Trusses
R502.12.2, R802.10.3
CFS-BCSI—(updated June 2016): Cold-formed Steel Building Component Safety Information (CFSBCSI)—Guide to Good Practice for Handling, Installing & Bracing of Cold-formed Steel Trusses
R505.1.3, R804.3.6
SFM State of California Department of Forestry and Fire Protection, Office of the State Fire Marshal, P.O. Box 944246, Sacramento, CA
944246-2460
SFM—12-3: Releasing Systems for Security Bars in Dwellings
SFM 12-7A-1: Exterior Wall Siding and Sheathing
SFM 12-7A-2: Exterior Window
SFM 12-7A-3: Horizontal Protection Underside
SFM 12-7A-4: Decking
SFM 12-7A-4A: Decking Alternate Method A
(The Office of the State Fire Marshal standards referred to above are found in the California Code of Regulations, Title 24, Part 12.)
TMS The Masonry Society 105 South Sunset Street, Suite Q Longmont, CO 80501
402—2022: Building Code Requirements for Masonry Structures
R404.1.2, R606.1, R606.1.1, R606.12.1, R606.12.2.3.1, R606.12.3.1, R703.12,
403—2017: Direct Design Handbook for Masonry Structures
R606.1, R606.1.1, R606.12.1, R606.12.3.1
404—2023: Standard for the Design of Architectural Cast Stone
R606.1
602—2022: Specification for Masonry Structures
R606.2.10, R606.2.13, R703.12
TPI Truss Plate Institute 2670 Crain Highway, Suite 203 Waldorf, MD 20601
ANSI/TPI 1—2022: National Design Standard for Metal Plate Connected Wood Truss Construction
R502.12.1, R802.10.2
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REFERENCED STANDARDS
UBC International Code Council, Inc. 500 New Jersey Avenue, NW 6th Floor Washington, DC 20001
UBC Standard 15-2: Test Standard for Determining the Fire Retardancy of Roof-covering Materials
R902
UBC Standard 15-3: Wood Shakes
R902
UBC Standard 15-4: Wood Shingles
R902
UL UL LLC 333 Pfingsten Road Northbrook, IL 60062
55A—2004: Materials for Built-Up Roof Coverings
R905.9.2
CWUIC § 3.2. High relevance — show source text
3.2. If nominal 6-inch-wide (152 mm) deck boards are used, a total of five boards shall be used for each deck. Changing the board width could change the number of deck boards.
12-7A-4A.6 Materials.
- Cross-sectional dimension. All deck board materials are to have cross-sectional dimensions equivalent to use in service.
- Description. The material under test should be described as completely as possible (unit weight, thickness, width and general information regarding composition).
- Condition of test material. Prior to testing, all materials (deck boards and joist material) shall be conditioned to a constant weight or for a minimum of 30 days at 73 ± 4°F (23 ± 2°C) and 50 ± 5 percent relative humidity, whichever occurs first. Constant weight shall be defined as occurring when the change in test material weight is less than or equal to 2 percent in a 24-hour period.
Note: The moisture content of joists shall be between 8- and 10-percent moisture content.
12-7A-4A.7 Under-deck flame test.
12-7A-4A.7.1 Equipment.
- Burner. A 12- x 12-inch (300 x 300 mm) diffusion burner shall be used. Natural gas, methane or propane shall be supplied to the burner through a metered control system. The gas supply to the burner shall produce a net heat output of 80 ± 4 kW throughout the flame exposure. Burner output can be determined from HRR or calculated from the gas flow rate, temperature and pressure.
- Oxygen depletion calorimeter. The equipment shall include a hood, associated ducting and instrumentation to provide HRR data by oxygen depletion calorimetry.
12-7A-4A.7.2 Test system preparation. See 12-7A-4 Figure No. 1.
- Deck support assembly. Assembly that holds the test deck over the burner.
- Baffle panels and joist support. Horizontal metal plates to support the deck joists along their full length, and also to confine burner flames to the underside of the deck boards located between the support joists.
- Back wall. Ceramic fiber board or another noncombustible panel product for the back wall material. Total height of the back wall is 8 feet (2.4 m).
- 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.
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12-7A-4A.7.3 Conduct of tests.
Airflow. The test is conducted under conditions of ambient airflow.
Number of tests. Conduct the test on three replicate assemblies.
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.
CWUIC § 12-7 High relevance — show source text
12-7A-4A.3 Referenced document.
- ASTM E108. Standard Test Methods for Fire Tests of Roof Coverings.
- California Building Code, Chapter 7A.
12-7A-4A.4 Definitions.
- Deck boards. Horizontal members that constitute the exposed surface of the ancillary structure.
- Heat release rate. The net rate of energy release as measured by oxygen depletion calorimetry.
12-7A-4A.5 Test assembly.
- 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).
- 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.
- 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 five boards shall be used for each deck. Changing the board width could change the number of deck boards.
12-7A-4A.6 Materials.
- Cross-sectional dimension. All deck board materials are to have cross-sectional dimensions equivalent to use in service.
- Description. The material under test should be described as completely as possible (unit weight, thickness, width and general information regarding composition).
- Condition of test material. Prior to testing, all materials (deck boards and joist material) shall be conditioned to a constant weight or for a minimum of 30 days at 73 ± 4°F (23 ± 2°C) and 50 ± 5 percent relative humidity, whichever occurs first. Constant weight shall be defined as occurring when the change in test material weight is less than or equal to 2 percent in a 24-hour period.
Note: The moisture content of joists shall be between 8- and 10-percent moisture content.
12-7A-4A.7 Under-deck flame test.
12-7A-4A.7.1 Equipment.
- Burner. A 12- x 12-inch (300 x 300 mm) diffusion burner shall be used. Natural gas, methane or propane shall be supplied to the burner through a metered control system. The gas supply to the burner shall produce a net heat output of 80 ± 4 kW throughout the flame exposure. Burner output can be determined from HRR or calculated from the gas flow rate, temperature and pressure.
- Oxygen depletion calorimeter. The equipment shall include a hood, associated ducting and instrumentation to provide HRR data by oxygen depletion calorimetry.
Frequently asked questions
Where in the CWUIC is SFM 12‑7A‑4 explicitly referenced?
SFM 12‑7A‑4 (and its Alternate 12‑7A‑4A) are referenced as acceptable decking test methods in § 504.7.3.2; the SFM documents themselves (test details and acceptance) are in the SFM standard text (12‑7A‑4 / 12‑7A‑4A) that the code references.
If my decking passes SFM 12‑7A‑4A, do I still need ASTM E84 / UL 723?
If you use the SFM 12‑7A‑4A path and the code allows it under § 504.7.3.2, you follow the SFM acceptance criteria. The ASTM E84 / UL 723 surface burning requirement is a separate path requirement under § 504.7.3.3 and applies when you are using the ASTM/UL path. Read § 504.7.3.2 carefully for wall‑covering interactions and exceptions.
How many test specimens are required for SFM decking tests?
SFM 12‑7A‑4/4A require three replicate assemblies; if one of the three fails, three additional tests must be performed and all three of the additional tests must pass. See the SFM acceptance rules.
What are the two main exposures in the full SFM 12‑7A‑4 decking test?
Part A = under‑deck heat release / 80 kW for 3 minutes; Part B = burning‑brand (upper surface) exposure: 12 mph wind for 40 minutes using a 2.2 lb Class A 12×12×2.25 in brand. These are SFM Part A and Part B requirements.
Who enforces or accepts these tests for code compliance?
The CWUIC (and the enforcing building/fire official) enforces the code requirements in § 504.7.3.2 / § 504.7.3.3; test reports and acceptance per the SFM standard are the documentation typically submitted for approval.
More in California Wildland-Urban Interface Code
- Administration and Definitions
- Board of Appeals, Administration & Enforcement (permits, code official duties, appeals process)
- Wildland‑Urban Interface Area Designation & Mapping
- Fire Service Access & Water Supply (fire apparatus roads, driveways, hydrants, draft sites, standby power)
- Wildland‑Urban Interface Area Requirements (access, water, premises identification, key boxes)
- Referenced Standards & Test Methods
- Special Building Construction Regulations (ignition‑resistant construction, roof/vent/assembly requirements)
- Appendices and Model Ordinances (vegetation plans, severity‑zone adoption, home‑hardening guidance)
- Fire Protection Requirements (fire protection plans, systems, safety element provisions)
- Referenced California Documents & Matrix (CCR/Title 14 & 19 cross‑references, statutory references)
- Vegetation Management & Defensible Space (vegetation plans, maintenance, fire‑smart characteristics)
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