CRSC · California Referenced Standards Code

How must thermal performance be represented and when must combustible-facing warnings appear?

Homeowner summary: Insulation sold in California must show a visible state‑approved label saying it was tested and meets standards; thermal claims (R‑value) must match certified test results and specific testing/derating rules, and if the product’s facing burns with a flame spread over 25 (ANSI/ASTM E84‑79), the package must clearly warn it “may be highly combustible if used in an exposed application” (see **§ 12-13-1557**) .

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Last reviewed: July 6, 2026

What the code requires — 2-4 sentences

Insulating materials sold in California must carry a visible, Commission‑approved statement certifying that a representative sample was tested by an approved laboratory and complies with the insulating‑material standards (§ 12-13-1557) . Any public claim of thermal performance must match the certified test results and any required derating under the article (§ 12-13-1557 (c)) . If a product’s flame spread exceeds 25 when tested with its facings/membranes exposed (ANSI/ASTM E84-79), the product must be clearly labeled that it “may be highly combustible if used in an exposed application” (§ 12-13-1557 (d)) .

The single most important requirement: packaging and public claims must reflect certified test results — and if facing-exposed flame spread > 25 (E84-79), a clear combustible-facing warning is mandatory.

Requirements in detail

1) Identification and certification on packaging

  • A visible, Commission‑approved statement must appear on the insulation, container, bundle or similar packaging certifying that a representative sample was tested by an approved laboratory and complies with the article’s requirements (§ 12-13-1557 (a),(b)) .
  • The Commission‑approved statement may be a design approved by the Executive Director or an identification of the manufacturer and a statement that the material meets California quality standards; shipments in bulk may meet the requirement via a bill of lading in limited circumstances (§ 12-13-1557 (b) (1)–(3)) .

2) How thermal performance must be represented

  • Thermal performance for building insulations must be stated in R value; other insulation types use thermal conductivity, conductance, or R value as appropriate (§ 12-13-1553 (3)) .
  • Any public representation (labels, literature, advertising) must be consistent with certification testing results and any derating required by this article (§ 12-13-1557 (c)) .
  • Test conditions: samples must be conditioned (73.4° ± 3.6°F, RH 50 ± 5%) and tested at an average temperature of 75° ± 2°F with at least a 40°F difference as required by the standard test procedures in the article (§ 12-13-1553 (4)) .
  • Aluminum foil and directional products must be tested in the heat‑flow direction(s) of intended application and that tested direction(s) be labeled on the material (§ 12-13-1553 (5)) .
  • Manufacturers may report supplemental thermal performance (e.g., material + air space) only if full test details and limitations are disclosed in the certification statement (§ 12-13-1553 (6)) .

3) Numeric tolerances and sampling rules

  • For most tests the certified thermal performance must be the average of at least three tests (unless special rules apply) (§ 12-13-1553 (7)) .
  • The average measured thermal performance of the certification tests shall not be more than 5 percent below the value specified on the product; additionally, any insulation sold within the state must not be more than 10 percent below the value shown on the product (§ 12-13-1553 (8)) .

4) Combustible-facing warning

  • If the product’s surface‑burning test with facings/membranes exposed (ANSI/ASTM E84-79) shows flame spread > 25, the product “must be clearly labeled with a statement that the product may be highly combustible if used in an exposed application” (§ 12-13-1557 (d)) .
  • The term “exposed application” is defined in the article and means an interior application where the product is not used in a construction assembly that provides a protective material in substantial contact with the facing or membrane surface (definition: § 12-13-1552 (e)) .
  • Exception: the combustible‑facing warning requirement does not apply to products meeting the specified sections of the 1994 Uniform Building Code (Sections 2602.1–2602.6) as noted in § 12-13-1557 (d) .

Decision-relevant quick table

Decision question Key value/threshold What the product must show Code reference
Is a Commission statement required on package? Any insulation sold in CA Visible, Commission‑approved certification statement that a representative sample was tested and complies § 12-13-1557 (a),(b)
In what units must building insulation be shown? N/A R value for building insulations (others use conductivity/conductance as appropriate) § 12-13-1553 (3)
Must public performance claims match tests? N/A Yes — public representations must be consistent with certification testing and derating § 12-13-1557 (c)
Test averaging tolerance for certification 5 percent Average of certification tests must be within 5% of labeled value § 12-13-1553 (7),(8)
In‑market tolerance 10 percent Product sold in CA must not measure more than 10% below labeled value § 12-13-1553 (8)
Combustible-facing warning needed? Flame spread > 25 (E84-79) with facings exposed Must be clearly labeled that product “may be highly combustible if used in an exposed application” § 12-13-1557 (d)
Aluminum foil/directional testing N/A Test heat‑flow direction(s) of intended application and label tested direction(s) § 12-13-1553 (5)
Supplemental air‑space claims N/A Allowed only if full test details and limitations are disclosed in certification § 12-13-1553 (6)

Exceptions & special cases

  • Bulk shipments: a statement in the bill of lading can satisfy the identification requirement only when the product is shipped in bulk or the container/product is not otherwise labeled by the manufacturer and the product is sold to its ultimate user (§ 12-13-1557 (b)(3)) .
  • Products that meet the specified 1994 Uniform Building Code sections (2602.1–2602.6) are exempt from the combustible‑facing warning in § 12-13-1557 (d) .
  • Aluminum foil insulation and other directional products have special test/label rules: test in the intended heat‑flow direction(s) and label those directions; unsupported foil thickness minimums and E84 test limits are given elsewhere in the article (§ 12-13-1553 (5); see also aluminum foil specs) .
  • Manufacturers that claim additional thermal value from facings or air spaces must still certify the base material value (without air space) and may report supplemental construction values only with full disclosure of test conditions and limitations (§ 12-13-1553 (6)) .

Common mistakes

  • Claiming an R‑value on packaging or advertising that is not supported by certification testing or that has not been derated as required — contravenes § 12-13-1557 (c) .
  • Using test results that exceed the allowed certification tolerance: the certification test average must be within 5 percent of the labeled value; relying on an average outside that window will fail the certification standard (§ 12-13-1553 (7),(8)) .
  • Omitting the Commission‑approved identification statement on packaging or using an unapproved statement format (the Executive Director must approve the design or statement) (§ 12-13-1557 (b)) .
  • Forgetting to add the combustible‑facing warning when facings are exposed during the E84 test and flame spread > 25 — this label is explicit in § 12-13-1557 (d) .
  • Failing to label aluminum‑foil insulation with the tested heat‑flow direction(s) as required by § 12-13-1553 (5) .

Worked example — concrete scenario

Scenario: A manufacturer labels a fiberglass batt as R‑13.

  1. They submit certification tests (three samples) for the representative thickness. The test results: R = 12.6, 12.4, 12.5.

    • Average test result = (12.6 + 12.4 + 12.5) / 3 = 12.5.
    • Difference from labeled R‑13 = 13.0 − 12.5 = 0.5 → percent below = 0.5/13.0 = 3.85%.
    • This passes the certification average tolerance (≤ 5% below) and so meets the certification test requirement (§ 12-13-1553 (7),(8)) .

  2. The manufacturer must display a visible Commission‑approved certification statement on the product packaging indicating a representative sample was tested and complies (§ 12-13-1557 (a),(b)) .

  3. If the test panel had averaged 12.0 instead, percent below = (13.0 − 12.0)/13.0 = 7.7%:

    • That would fail the 5% certification average requirement (so certification cannot be based on these tests) but still be within the 10% in‑market limit for sale. However, because the certification average fails, the product could not be certified without retesting or relabeling to a lower value (§ 12-13-1553 (7),(8)) .

  4. Separately, if the product’s facing was tested with facings exposed and an ANSI/ASTM E84‑79 test produced flame spread = 30, the package must include the clear warning that the product “may be highly combustible if used in an exposed application” (unless the product meets the referenced UBC exceptions) (§ 12-13-1557 (d)) .

Related provisions

  • § 12-13-1552 — Definitions (e.g., Exposed application, Representative sample, Representative thickness) .
  • § 12-13-1553 — Quality standards and test procedures (units, conditioning, foil rules, averaging, tolerances) .
  • § 12-13-1558 — Inspection authority for manufacturers, distributors, retailers (sampling/records) .
  • § 12-13-1559 — Commission authority to conduct independent performance tests .
  • See also test‑method references called out in the article: ANSI/ASTM E84‑79 (surface burning) and ANSI/ASTM C236‑66 / C177‑76 / C518‑76 for thermal performance testing (cited within the article) .

Code references

Grounded in the retrieved California Referenced Standards Code — click a citation to read the verbatim passage:

  • CRSC § 2602.1 High relevance — show source text

    (c) Any representation of thermal performance which appear on any label, literature, advertising or any other writing intended for the public shall be consistent with the certification testing results and derating required by this article.

    (d) Any insulation with facings and membranes for which the flame spread exceeds 25 when tested with facings and membranes exposed to the flame during the ANSI/ASTM E84-79 test must be clearly labeled with a statement that the product may be highly combustible if used in an exposed application. This subsection shall not apply to any product meeting the requirements of Sections 2602.1-2602.6 of the 1994 Uniform Building Code.

    Authority: Section 25218(e), Public Resources Code.

    Reference: Section 25921, Public Resources Code.

    HISTORY:

    1. Amendment of subsections (a) and (c) filed 8-10-81; designated effective 9-22-81 (Register 81, No. 33).

    INSPECTIONS

    Sec. 12-13-1558.

    After September 22, 1981, the Commission may, upon the consent of the owner or lessee, or upon securing a search warrant, have access, during normal working hours, to the premises of manufacturers, distributors and retailers of insulating material sold for installation within the state for the purpose of determining compliance with the standards promulgated pursuant to Chapter 10.5 of the California Public Resources Code . Such access shall be for the purposes of obtaining representative samples of subject insulation and inspecting records and documents pertaining to tests by approved testing labs.

    Authority: Section 25218 (e), Public Resources Code.

    Reference: Section 25926, Public Resources Code.

    HISTORY:

    1. Amendment filed 8-10-81; designated effective 9-22-81 (Register 81, No. 33).

    PERFORMANCE TESTS

    Sec. 12-13-1559.

    The Commission may conduct, or may contract with others to conduct, independent performance tests of representative samples of insulation sold in the state to determine compliance with standards adopted pursuant to Chapter 10.5 of the California Public Resources Code . Such tests shall form the basis for instituting enforcement proceedings.

    Authority: Section 25218 (e), Public Resources Code.

    Reference: Section 25926, Public Resources Code.

    HISTORY:

    1. Amendment filed 8-10-81; designated effective 9-22-81 (Register 81, No. 33).

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    STANDARDS FOR INSULATING MATERIAL

    COSTS OF INSPECTION AND TESTING (RESERVED)

    Sec. 12-13-1560.

    Authority: Section 25218 (e), Public Resources Code.

    Reference: Section 25926, Public Resources Code.

    HISTORY:

    1. Repealer filed 8-10-81; designated effective 9-22-81 (Register 81, No. 33).

    ENFORCEMENT (RESERVED)

    Sec. 12-13-1561.

    Authority: Section 25218 (e), Public Resources Code.

    Reference: Section 25931, Public Resources Code.

    HISTORY:

    1. Repealer filed 6-26-79; effective thirtieth day thereafter (Register 79, No. 26).

    RELEASE OF INFORMATION

  • CRSC § 25921.1 High relevance — show source text

    Reference: Sections 25921 and 25921.1, Public Resources Code.

    HISTORY:

    1. Amendment of subsections (a), (b) (4), (b) (6) and (f) filed 8-10-81; designated effective 9-22-81 (Register 81, No. 33).

    QUALITY ASSURANCE (RESERVED)

    Sec. 12-13-1556.

    Authority: Section 25218 (e), Public Resources Code.

    Reference: Section 25921.1, Public Resources Code.

    HISTORY:

    1. Repealer filed 8-10-81; designated effective 9-22-81 (Register 81, No. 33).

    IDENTIFICATION

    Sec. 12-13-1557.

    (a) Except as specified in subsection (b), Item 3, of this section, no insulation shall be sold in California on or after September 22, 1981, unless the insulating material, container, bundle or similar packaging material bears a visible Commission approved statement certifying that a representative sample of the insulation material has been tested and approved by an approved laboratory and complies with the requirements of this article.

    (b) The Commission-approved statement shall consist of either:

    1. A design or statement approved by the Executive Director, or

    2. An identification of the manufacturer and any statement that the material meets the quality standards of the State of California.

    3. A statement that the material meets the quality standards of the State of California included in the bill of lading shall meet the requirements of this section only if the product is being shipped in bulk, or the container or product is not otherwise labeled by the manufacturer and the product is being sold to its ultimate user.

    (c) Any representation of thermal performance which appear on any label, literature, advertising or any other writing intended for the public shall be consistent with the certification testing results and derating required by this article.

    (d) Any insulation with facings and membranes for which the flame spread exceeds 25 when tested with facings and membranes exposed to the flame during the ANSI/ASTM E84-79 test must be clearly labeled with a statement that the product may be highly combustible if used in an exposed application. This subsection shall not apply to any product meeting the requirements of Sections 2602.1-2602.6 of the 1994 Uniform Building Code.

    Authority: Section 25218(e), Public Resources Code.

    Reference: Section 25921, Public Resources Code.

    HISTORY:

    1. Amendment of subsections (a) and (c) filed 8-10-81; designated effective 9-22-81 (Register 81, No. 33).

    INSPECTIONS

    Sec. 12-13-1558.

    After September 22, 1981, the Commission may, upon the consent of the owner or lessee, or upon securing a search warrant, have access, during normal working hours, to the premises of manufacturers, distributors and retailers of insulating material sold for installation within the state for the purpose of determining compliance with the standards promulgated pursuant to Chapter 10.5 of the California Public Resources Code . Such access shall be for the purposes of obtaining representative samples of subject insulation and inspecting records and documents pertaining to tests by approved testing labs.

    Authority: Section 25218 (e), Public Resources Code.

    Reference: Section 25926, Public Resources Code.

    HISTORY:

  • CRSC § 73.4 High relevance — show source text

    A manufacturer may appeal the Executive Director’s determination to the full Commission.

    1. Thermal performance of building insulations shall be stated in R value. Other insulations shall use thermal conductivity, conductance or R value as appropriate.

    2. All thermal performance tests shall be conducted on materials which have been conditioned at 73.4° ± 3.6°F and a relative humidity of 50 ± 5 percent for 24 hours immediately preceding the tests. The average testing temperature shall be 75° ± 2°F with at least a 40°F (4°C) temperature difference.

    3. Aluminum foil insulation shall be tested according to ANSI/ASTM C236-66 to determine the thermal performance in horizontal, upward and downward directions. The tested thermal performance in the heat-flow direction or directions of the intended application shall be labeled on the material. The manufacturer shall test once in each direction of intended application, except that for products labeled with only one heat-flow direction, the manufacturer shall test two samples in that direction.

    4. Insulation (other than aluminum foil insulation materials) for which additional value is claimed for facings and air spaces shall be tested for thermal performance as a material without the air space pursuant to this article. The manufacturer may elect to report additional thermal performance values of a given construction tested according to ANSI/ASTM C236-66 for that construction as long as full details of that construction are also disclosed in the certification statement and pursuant to Section 1557 (c) of this article. If a manufacturer elects to report a thermal performance value for a material plus an air space (as supplemental information to the required material thermal performance), but not necessarily for a full construction, the manufacturer must also disclose the conditions of the test and the limitations to the attainment of that result.

    5. Except as provided in Items 5 and 6, the thermal performance test results certified under Section 1555 of this article shall be the average of the values obtained from at least three tests.

    6. The average measured thermal performance of the tests required by Items 5, 6 and 7 shall not be more than 5 percent below the value specified on the product. In addition, all insulation material sold within the state after September 22, 1981, shall have a measured thermal performance not more than 10 percent below the value specified on the product.

    7. All numbered test descriptions shall be contained in the document “Test Descriptions for Insulating Material” dated February 27, 1981.

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    STANDARDS FOR INSULATING MATERIAL

    1. Facings on representative samples may be removed or modified by slitting for the ANSI/ASTM C177-76 and ANSI/ASTM C518-76 tests.

    2. All thermal performance testing equipment used for testing insulating materials shall be calibrated with samples referenced to the United States National Bureau of Standards.

    3. Manufacturers of loose fill insulations for which no settled density test is required by this section shall be required to include the installed design density in the identifying information described in Section 1557. The manufacturer shall provide sufficient documentation to establish a valid basis for the determination of installed design density. The Executive Director shall determine whether a valid basis exists for the installed design density claimed by the manufacturer. If it is determined that a valid basis does not exist, the director may assign an appropriate installed design density or may require an appropriate test to determine the installed design density. The manufacturer may appeal the Executive Director’s determination to the full Commission.

  • CRSC § 410-66. Medium relevance — show source text

    **

    1. Composition. Vermiculite loose fill insulation shall be produced by the expanding or exfoliating of natural vermiculate or by grading and heating.
    2. Thermal performance. Determination of the thermal performance shall be in accordance with ANSI/ASTM C177-76, ANSI/ASTM C236-66 or ANSI/ASTM C615-76 at the manufacturer’s option.
    3. Density. Density shall be determined according to installed design density. All tests except the ANSI/ ASTM E84-79 test shall be conducted at the installed design density.
    4. Resistance to combustion. Resistance to combustion shall be determined by the use of the Attic Floor Radiant Panel Test, as described in the United States General Services Administration insulation standard HH-I-515D as amended October 11, 1979.

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    STANDARDS FOR INSULATING MATERIAL

    1. Identification. Containers of vermiculite shall be marked with the type (pouring or pneumatic), the net weight and the manufacturer’s recommendations for installation including minimum thickness, maximum coverage and installed design density to provide the levels of thermal performance shown. Manufacturer’s installation recommendations shall include precautions according to the California Electric Code Section 410-66.

    Products which may be used for pressure fill retrofit wall application shall be marked with the recommended wall density to prevent settling and separately marked with the tested thermal performance for such applications.

    Authority: Sections 25402(a) and 25920, Public Resources Code.

    Reference: Sections 25920-25922, Public Resources Code.

    HISTORY:

    1. Amendment of subsection (a) (9) filed 4-2-79; effective thirtieth day thereafter (Register 79, No. 14).
    2. Editorial correction of subsection designations with subsection (l) (4) (Register 79, No. 17).
    3. Amendment filed 8-10-81; designated effective 9-22-81 (Register 81, No. 33).
    4. New subsection (m) (2) (J) filed 9-11-81; effective thirtieth day thereafter (Register 81, No. 37).
    5. Editorial correction of subsection (k) (3) (B) filed 1-13-82 (Register 82, No. 3).
    6. Amendment of subsections (a) (5) and (a) (8) filed 5-5-82; effective thirtieth day thereafter (Register 82, No. 19).
    7. Editorial correction of subsection (m) printing error (Register 82, No. 44).

    APPROVAL OF TESTING LABORATORIES

    Sec. 12-13-1554.

    (a) Except as provided in subsection (b), laboratories shall be approved using the procedures described in the Criteria for the Approval of Testing Laboratories, dated October 27, 1978. The Executive Director shall approve any laboratory that meets the standards described in the Criteria for the Approval of Testing Laboratories, dated October 27, 1978. A testing laboratory shall have the right to appeal to the full Commission any denial of approval by the Executive Director.

  • CRSC § 0.75. Medium relevance — show source text

    1. Within 180 days after the availability of appropriate representative thickness calibration samples from the National Bureau of Standards, all insulating materials thicker than 1 inch (25 mm), which have not previously been tested at the representative thickness of a representative sample, shall be tested at representative thickness and recertified. Test results and a revised certification statement will be submitted to the Executive Director. The Executive Director shall determine if and when an appropriate representative thickness calibration sample is available from the National Bureau of Standards and shall publish a list of available representative thickness calibration samples. The manufacturer may appeal the Executive Director’s determination to the full Commission.

    2. All products which may be used for pressure fill retrofit wall application shall be separately tested for thermal performance using a sample prepared at the manufacturer’s recommended wall density for such applications.

    3. All water heater insulation kits and nonpreformed pipe insulation shall be tested for thermal performance at the installed compressed thickness of a typical application. Installed compressed thickness shall be determined according to Test Description Number 6. All nonpreformed duct insulation shall be labeled, in accordance with Section 1557(c), with an installed R -value equal to the R -value of the uncompressed insulation times 0.75. (b) Aluminum foil.

    4. Composition. The insulation shall have uniform flat surfaces and shall not be crumpled, torn or punctured. Aluminum foil shall contain not less than 99 percent aluminum. Kraft paper and flangeboard shall meet the requirements of ANSI/TAPPI T400 0S75. Flangeboard used for more than two insulation layers shall be of 28 point grade minimum, if single sheet flangeboard is used or 14 point grade minimum if double sheet flangeboard is used. Adhesive used in bonding shall be waterproof and shall show no sign of bleeding when tested in accordance with the following test procedure. Bleeding at cut edges may be disregarded. Specimens for tests shall consist of pieces of insulation cut to approximately 3 by 6 inches (76 mm by 152 mm), suspended in a vertical position and heated to a temperature of 180°F ± 5°F for at least 5 hours. At the end of heating period, examine the reflective surfaces to determine whether the adhesive has bled or extruded through the surface, or delamination has occurred.

    5. Thermal performance. Thermal performance shall be determined according to ANSI/ASTM C236-66. The test panel shall consist of a panel utilizing a wooden frame of 2 by 6 inches (51 mm by 152 mm) construction covered with [3] / 4 -inch (19 mm) plywood on both sides. The resultant thermal performance shall be based on the insulation only.

    6. Size. Layers of insulation composed of unsupported foil that is exposed shall have a minimum thickness of 0.0004 inch (0.01 mm). Unsupported foil that is sandwiched in a multilayer sheet shall have a minimum thickness of 0.00035 inch (0.009 mm). Foil bonded to kraft paper shall have a minimum thickness of 0.00025 inch (0.006 mm). Minimum space between layers of a multilayer sheet shall conform with the United States General Services Administration insulation standard HH-I-1252B dated August 18, 1976.

    7. Resistance to combustion. Surface-burning characteristics shall be determined according to the ANSI/ ASTM E84-79, and shall not exceed the following values:

    Flame spread. . . . . . . . . . . . . . . . . .

  • CRSC § 12-7 Medium relevance — show source text

    Note: In tests of assemblies with roof coverings, the thermocouples and pads shall be placed on top of the roof covering.

    (b) Ceiling-floor, ceiling-roof assemblies. Temperature readings shall be taken in the center of the plenum, on the bottom side of the floor or roof deck, and on the structural members in fire-endurance tests of ceiling-floor and ceiling-roof assemblies. Thermocouples shall be located on structural steel as specified in Section 12-7-110 (c). In combustible assemblies five or more thermocouples shall be located on the bottom of soffit of joists or beams. Thermocouples shall be placed in representative locations such as at midspan, over joints in the ceiling, over light fixtures, over air-outlet openings or similar locations.

    (c) Thermocouple locations on unexposed side. Temperature readings shall be taken at not less than nine points on the surface of the unexposed side. Five of these shall be symmetrically disposed, one to be approximately at the center of the specimen and four at approximately the center of its quarter sections. The other four shall be located at the discretion of the testing authority to obtain representative information on the performance of the construction under test. None of the thermocouples shall be located nearer than 1 [1] / 2 times the thickness of the construction, or nearer than 12 inches (305 mm) to the edges. An exception shall be made in those cases where there is an element of the construction at the edges which is not otherwise represented in the remainder of the construction. Also, none of the thermocouples shall be located opposite or on top of beams, girders, pilasters or other structural members if temperatures at such points will obviously be lower than at other more representative locations.

    (d) Temperature intervals. Temperature readings shall be taken at intervals not exceeding 15 minutes until a reading exceeding 212°F (100°C) has been obtained at any one point. Thereafter the readings may be taken more frequently at the discretion of the testing body, but the intervals need not be less than 5 minutes.

    (e) Maximum unexposed temperature rise. Where the conditions of acceptance place a limitation on the rise of temperature of the unexposed surface, the temperature end point of the fire endurance period shall be determined by the average of the measurements taken at individual points; except that if a temperature rise 30 percent in excess of the specified limit occurs at any one of these points, the remainder shall be ignored and the fire endurance period judged as ended.

    CLASSIFICATION AS DETERMINED BY TEST

    Sec. 12-7-103.

    (a) Fire exposure report. Results shall be reported in accordance with the performance tests prescribed in these methods. They shall be expressed in time periods of resistance, to the nearest integral minute. Reports shall include observations of significant details of behavior of the material or construction during the test and after the furnace fire is cut off, including information on defor

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    FIRE-RESISTIVE STANDARDS

    mation, spalling, cracking, burning of the specimen or its component parts, continuance of flaming and production of smoke. The form and contents of reports shall be in accordance with Section 12-7-115.

  • CRSC § 0.75. Medium relevance — show source text
    1. Except as provided in Items 5 and 6, the thermal performance test results certified under Section 1555 of this article shall be the average of the values obtained from at least three tests.
    2. The average measured thermal performance of the tests required by Items 5, 6 and 7 shall not be more than 5 percent below the value specified on the product. In addition, all insulation material sold within the state after September 22, 1981, shall have a measured thermal performance not more than 10 percent below the value specified on the product.
    3. All numbered test descriptions shall be contained in the document “Test Descriptions for Insulating Material” dated February 27, 1981.

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    1. Facings on representative samples may be removed or modified by slitting for the ANSI/ASTM C177-76 and ANSI/ASTM C518-76 tests.

    2. All thermal performance testing equipment used for testing insulating materials shall be calibrated with samples referenced to the United States National Bureau of Standards.

    3. Manufacturers of loose fill insulations for which no settled density test is required by this section shall be required to include the installed design density in the identifying information described in Section 1557. The manufacturer shall provide sufficient documentation to establish a valid basis for the determination of installed design density. The Executive Director shall determine whether a valid basis exists for the installed design density claimed by the manufacturer. If it is determined that a valid basis does not exist, the director may assign an appropriate installed design density or may require an appropriate test to determine the installed design density. The manufacturer may appeal the Executive Director’s determination to the full Commission.

    4. Within 180 days after the availability of appropriate representative thickness calibration samples from the National Bureau of Standards, all insulating materials thicker than 1 inch (25 mm), which have not previously been tested at the representative thickness of a representative sample, shall be tested at representative thickness and recertified. Test results and a revised certification statement will be submitted to the Executive Director. The Executive Director shall determine if and when an appropriate representative thickness calibration sample is available from the National Bureau of Standards and shall publish a list of available representative thickness calibration samples. The manufacturer may appeal the Executive Director’s determination to the full Commission.

    5. All products which may be used for pressure fill retrofit wall application shall be separately tested for thermal performance using a sample prepared at the manufacturer’s recommended wall density for such applications.

    6. All water heater insulation kits and nonpreformed pipe insulation shall be tested for thermal performance at the installed compressed thickness of a typical application. Installed compressed thickness shall be determined according to Test Description Number 6. All nonpreformed duct insulation shall be labeled, in accordance with Section 1557(c), with an installed R -value equal to the R -value of the uncompressed insulation times 0.75. (b) Aluminum foil.

    7. Composition. The insulation shall have uniform flat surfaces and shall not be crumpled, torn or punctured. Aluminum foil shall contain not less than 99 percent aluminum. Kraft paper and flangeboard shall meet the requirements of ANSI/TAPPI T400 0S75. Flangeboard used for more than two insulation layers shall be of 28 point grade minimum, if single sheet flangeboard is used or 14 point grade minimum if double sheet flangeboard is used.

  • CRSC § 1.5.1 Medium relevance — show source text

    Theoretical methods being developed offer an alternative to the full-scale fire tests discussed above. For example, Section 4302(b) of the 1979 edition of the Uniform Building Code specifically allows an engineering design for fire resistance in lieu of conducting full-scale tests. These techniques draw upon computer simulation and mathematical modeling, thermodynamics, heatflow analysis and materials science to predict the fire performance of building materials and assemblies.

    One theoretical method, known as the “Ten Rules of Fire Endurance Ratings,” was published by T. Z. Harmathy in the May, 1965 edition of Fire Technology (see Bibliography entry 35). Harmathy’s Rules provide a foundation for extending the data within the Appendix tables to analyze or upgrade current as well as archaic building materials or assemblies.

    HARMATHY'S TEN RULES

    Rule 1: The “thermal” fire endurance of a construction consisting of a number of parallel layers is greater than the sum of the “thermal” fire endurances characteristic of the individual layers when exposed separately to fire. (Note: The “thermal” fire endurance is the time at which the average temperature on the unexposed side of a construction exceeds its initial value by 250°F (121°C) when the other side is exposed to the “standard” fire specified by ASTM Test Method E-19.)

    The minimum performance of an untested assembly can be estimated if the fire endurance of the individual components is known. Though the exact rating of the assembly cannot be stated, the endurance of the assembly is greater than the sum of the endurance of the components.

    When a building assembly or component is found to be deficient, the fire endurance can be upgraded by providing a protective membrane. This membrane could be a new layer of brick, plaster or drywall. The fire endurance of this membrane is called the “finish rating.” Appendix tables 1.5.1 and 1.5.2 contain the finish ratings for the most commonly employed materials. (See also the notes to Rule 2.)

    The test criteria for the finish rating is the same as for the thermal fire endurance of the total assembly: average temperature increases of 250°F (121°C) above ambient or 325°F (163°C) above ambient at any one place with the membrane being exposed to the fire. The temperature is measured at the interface of the assembly and the protective membrane.

    Rule 2: The fire endurance of a construction does not decrease with the addition of further layers.

    Harmathy notes that this rule is a consequence of the previous rule. Its validity follows from the fact that the additional layers increase both the resistance to heat flow and the heat capacity of the construction. This, in turn, reduces the rate of temperature rise at the unexposed surface.

    This rule is not just restricted to “thermal” performance but affects the other fire test criteria: direct flame passage, cotton waste ignition and load bearing performance. This means that certain restrictions must be imposed on the materials to be added and on the loading conditions. One restriction is that a new layer, if applied to the exposed surface, must not produce additional thermal stresses in the construction, i.e., its thermal expansion characteristics must be similar to those of the adjacent layer. Each new layer must also be capable of contributing enough additional strength to the assembly to sustain the added dead load. If this requirement is not fulfilled, the allowable live load must be reduced by an amount equal to the weight of the new layer. Because of these limitations, this rule should not be applied without careful consideration.

    2025 CALIFORNIA EXISTING BUILDING CODE RESOURCE A-9

  • CRSC § 8-10 Medium relevance — show source text

    (o) “Urea formaldehyde foam” means a cellular plastic insulation material generated in a continuous stream by mixing the components which are a urea formaldehyde resin, air and a foaming agent.

    Authority: Sections 25920 and 25922, Public Resources Code.

    Reference: Sections 25915 (a), 25920, 25921 and 25922, Public Resources Code.

    HISTORY:

    1. Amendment filed 8-10-81; designated effective 9-22-81 (Register 81, No. 33).

    QUALITY STANDARDS

    Sec. 12-13-1553. The manufacturer shall cause the testing of samples of insulating material for conformity with the quality standards described in this section.

    (a) General testing provisions. In testing any material pursuant to this section, the following general procedures shall be used.

    1. All tests with the exception of the ANSI/ASTM E84-79 test shall be conducted using representative samples at the representative thickness of the insulation, except that when the final use of an insulating material entails a thickness less than the representative thickness, then the insulating material will be tested at the lesser thickness.

    2. Where uniformity of product ensures consistency of test results across a product grouping, test results for one may be used for certification of other products within that product group. The manufacturer shall provide sufficient documentation to establish a valid basis for applying a particular test result to other products within the group. The Executive Director shall determine whether a valid basis exists for grouping products for testing pursuant to this subsection. If it is determined that a valid basis does not exist, individual tests shall be required. A manufacturer may appeal the Executive Director’s determination to the full Commission.

    3. Thermal performance of building insulations shall be stated in R value. Other insulations shall use thermal conductivity, conductance or R value as appropriate.

    4. All thermal performance tests shall be conducted on materials which have been conditioned at 73.4° ± 3.6°F and a relative humidity of 50 ± 5 percent for 24 hours immediately preceding the tests. The average testing temperature shall be 75° ± 2°F with at least a 40°F (4°C) temperature difference.

    5. Aluminum foil insulation shall be tested according to ANSI/ASTM C236-66 to determine the thermal performance in horizontal, upward and downward directions. The tested thermal performance in the heat-flow direction or directions of the intended application shall be labeled on the material. The manufacturer shall test once in each direction of intended application, except that for products labeled with only one heat-flow direction, the manufacturer shall test two samples in that direction.

    6. Insulation (other than aluminum foil insulation materials) for which additional value is claimed for facings and air spaces shall be tested for thermal performance as a material without the air space pursuant to this article. The manufacturer may elect to report additional thermal performance values of a given construction tested according to ANSI/ASTM C236-66 for that construction as long as full details of that construction are also disclosed in the certification statement and pursuant to Section 1557 (c) of this article. If a manufacturer elects to report a thermal performance value for a material plus an air space (as supplemental information to the required material thermal performance), but not necessarily for a full construction, the manufacturer must also disclose the conditions of the test and the limitations to the attainment of that result.

  • CRSC § 17.4 Medium relevance — show source text

    8|17.4|1.5|2.5|3.4|5.1|0.6|1.0|1.3|1.9| |10|7.7|13.1|17.8|26.3|2.3|3.8|5.2|7.7|0.8|1.4|2.0|2.9| |12|10.8|18.4|24.9|NP|3.2|5.4|7.3|10.7|1.2|2.0|2.7|4.0| |14|14.4|24.5|NP|NP|4.2|7.1|9.6|14.3|1.6|2.7|3.6|5.4| |16|18.4|NP|NP|NP|5.4|9.1|12.4|18.3|2.0|3.4|4.7|6.9| |18|22.9|NP|NP|NP|6.7|11.4|15.4|22.7|2.5|4.3|5.8|8.6| |20|27.8|NP|NP|NP|8.1|13.8|18.7|27.6|3.1|5.2|7.0|10.4| |22|NP|NP|NP|NP|9.7|16.5|22.3|NP|3.7|6.2|8.4|12.4| |24|NP|NP|NP|NP|11.4|19.3|26.2|NP|4.3|7.3|9.9|14.6| |26|NP|NP|NP|NP|13.2|22.4|NP|NP|5.0|8.5|11.4|16.9| |28|NP|NP|NP|NP|15.1|25.7|NP|NP|5.7|9.7|13.1|19.4| |30|NP|NP|NP|NP|17.2|NP|NP|NP|6.5|11.0|14.9|22.0| |32|NP|NP|NP|NP|19.4|NP|NP|NP|7.3|12.4|16.8|24.8| |34|NP|NP|NP|NP|21.7|NP|NP|NP|8.2|13.9|18.8|NP| |36|NP|NP|NP|NP|24.1|NP|NP|NP|9.1|15.4|20.9|NP| |For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 0.063 L/s, 1 pound per square inch = 6.895 kPa.
    NP = Not Permitted. Pressure loss exceeds reasonable limits.
    a. Values are applicable for underground piping materials listed in_ the California Plumbing Code_ and are based on an SDR of 11 and a Hazen Williams C Factor of 150.
    b. Values include the following length allowances for fittings: 25-percent length increase for actual lengths up to 100 feet and 15-percent length increase for actual lengths over
    100 feet.
    c. Flow rate from Section P2904.4.2.

  • CRSC § 1.1.4 Medium relevance — show source text

    The test criteria for the finish rating is the same as for the thermal fire endurance of the total assembly: average temperature increases of 250°F (121°C) above ambient or 325°F (163°C) above ambient at any one place with the membrane being exposed to the fire. The temperature is measured at the interface of the assembly and the protective membrane.

    Rule 2: The fire endurance of a construction does not decrease with the addition of further layers.

    Harmathy notes that this rule is a consequence of the previous rule. Its validity follows from the fact that the additional layers increase both the resistance to heat flow and the heat capacity of the construction. This, in turn, reduces the rate of temperature rise at the unexposed surface.

    This rule is not just restricted to “thermal” performance but affects the other fire test criteria: direct flame passage, cotton waste ignition and load bearing performance. This means that certain restrictions must be imposed on the materials to be added and on the loading conditions. One restriction is that a new layer, if applied to the exposed surface, must not produce additional thermal stresses in the construction, i.e., its thermal expansion characteristics must be similar to those of the adjacent layer. Each new layer must also be capable of contributing enough additional strength to the assembly to sustain the added dead load. If this requirement is not fulfilled, the allowable live load must be reduced by an amount equal to the weight of the new layer. Because of these limitations, this rule should not be applied without careful consideration.

    2025 CALIFORNIA EXISTING BUILDING CODE RESOURCE A-9

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

    RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

    Particular care must be taken if the material added is a good thermal insulator. Properly located, the added insulation could improve the “thermal” performance of the assembly. Improperly located, the insulation could block necessary thermal transmission through the assembly, thereby subjecting the structural elements to greater temperatures for longer periods of time, and could cause premature structural failure of the supporting members.

    Rule 3: The fire endurance of constructions containing continuous air gaps or cavities is greater than the fire endurance of similar constructions of the same weight, but containing no air gaps or cavities.

    By providing for voids in a construction, additional resistances are produced in the path of heat flow. Numerical heat flow analyses indicate that a 10 to 15 percent increase in fire endurance can be achieved by creating an air gap at the midplane of a brick wall. Since the gross volume is also increased by the presence of voids, the air gaps and cavities have a beneficial effect on stability as well. However, constructions containing combustible materials within an air gap may be regarded as exceptions to this rule because of the possible development of burning in the gap.

    There are numerous examples of this rule in the tables. For instance:

    Table 1.1.4; Item W-8-M-82: Cored concrete masonry, nominal 8 inch thick wall with one unit in wall thickness and with 62 percent minimum of solid material in each unit, load bearing (80 PSI). Fire endurance: 2 [1] / 2 hours.

  • CRSC § 1207.6 Medium relevance — show source text
    TABLE 1207.6—ELECTROCHEMICAL ESS TECHNOLOGY-SPECIFIC REQUIREMENTS Col2 Col3 Col4 Col5 Col6 Col7 Col8 Col9 Col10
    COMPLIANCE REQUIREDb COMPLIANCE REQUIREDb BATTERY TECHNOLOGY BATTERY TECHNOLOGY BATTERY TECHNOLOGY BATTERY TECHNOLOGY BATTERY TECHNOLOGY BATTERY TECHNOLOGY OTHER ESS
    AND BATTERY
    TECHNOLOGIESb    		 CAPACITOR
    ESSb
    Feature Section Lead-
    acid    		 Nickel
    cadmium
    (Ni-Cd),
    nickel-metal
    hydride
    (Ni-MH) and
    nickel zinc
    (Ni-Zn)    		 Zinc-
    manganese
    dioxide
    (Zn-MnO2)    		 Lithium-ion Flow Sodium
    nickel
    chloride    		 Sodium
    nickel
    chloride    		 Sodium
    nickel
    chloride
    Exhaust
    ventilation    		 1207.6.1 Yes Yes Yes No Yes No Yes Yes
    Explosion control 1207.6.3 Yesa Yesa Yes Yes No Yes Yes Yes
    Safety caps 1207.6.4 Yes Yes No No No No Yes Yes
    Spill control and
    neutralization    		 1207.6.2 Yesc Yesc Yesf No Yes No Yes Yes
    Thermal
    runaway    		 1207.6.5 Yesd Yes Yese Yese No Yes Yese Yes
    a. Not required for lead-acid and nickel-cadmium batteries at facilities under the exclusive control of communications utilities that comply with NFPA 76 and operate at less
    than 50 VAC and 60 VDC.
    b. Protection shall be provided unless documentation acceptable to the fire code official is provided in accordance with Section 104.2.2 that provides justification why the
    protection is not necessary based on the technology used.
    c. Applicable to vented-type (i.e., flooded) nickel-cadmium and lead-acid batteries.
    d. Not required for vented-type (i.e., flooded) batteries.
    e. The thermal runaway protection is permitted to be part of a battery management system that has been evaluated with the battery as part of the evaluation to UL 1973.
    f. Not required for batteries with jelled electrolyte.    		 a. Not required for lead-acid and nickel-cadmium batteries at facilities under the exclusive control of communications utilities that comply with NFPA 76 and operate at less
    than 50 VAC and 60 VDC.
    b. Protection shall be provided unless documentation acceptable to the fire code official is provided in accordance with Section 104.2.2 that provides justification why the
    protection is not necessary based on the technology used.
    c.

Frequently asked questions

Who must put the Commission‑approved statement on the packaging?

The manufacturer (or the responsible party for the product packaging) must ensure a visible, Commission‑approved certification statement appears on the insulation or its container per § 12-13-1557 (a),(b) .

What if I advertise a higher R‑value because of an air space in an assembly?

You can publish supplemental performance for a construction that includes air spaces only if you also certify and disclose the base material test (without the air space) and fully disclose test details and limitations in the certification statement (§ 12-13-1553 (6)) .

When is the combustible‑facing warning not required?

It is not required for products that meet the specified sections of the 1994 Uniform Building Code (Sections 2602.1–2602.6) as noted in § 12-13-1557 (d) .

If my product’s certification tests average 6% below the label, can I still sell it?

No — the certification test average must be within 5% of the labeled value to satisfy the certification requirements; however, in‑market measured performance must be within 10% for sale. Failing the 5% certification test means the product cannot be certified without corrective action (§ 12-13-1553 (7),(8)) .

Are there special labeling rules for foil insulation?

Yes — aluminum foil insulation must be tested according to ANSI/ASTM C236‑66 in the applicable heat‑flow direction(s) and the tested heat‑flow direction(s) must be labeled on the material (§ 12-13-1553 (5)) .

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