CBC · California Building Code

Foam Plastics, Insulation & Acoustical Systems

This hub summarizes where the CBC controls foam plastics, foam insulation, interior trim and acoustical systems and points to the governing sections.

Last reviewed: July 5, 2026

Overview

This part of the California Building Code (CBC) governs the use of foam plastics and plastic materials as insulation, interior finish/trim, veneers and light‑transmitting elements, and it also ties into the rules for thermal/combustion performance and required testing. These topics are collected in Chapter 26 (Plastic) with the general scope and definitions in §2601.1 and the chapter index pointing to the related sections.

Fire performance, labeling, testing and thermal‑barrier requirements are central: §2603 (Foam Plastic Insulation) sets material standards, labeling and surface‑burning (flame‑spread and smoke) criteria, and allows special approvals based on large‑scale tests; §2604 addresses interior finish and trim restrictions for foam plastics and references Chapter 8 for interior finish requirements. These provisions protect life‑safety and structural performance while enabling permitted uses of foam plastics.

Acoustical and insulation systems are handled both in Chapter 7/8 performance provisions and in the specific insulation and acoustical sections: Section 807 (Insulation) and Section 808 (Acoustical Ceiling Systems) govern thermal and sound insulation performance and installation standards that interact with the foam‑plastic rules.

In this section

Code references

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

  • CBC § 1.11. High relevance — show source text

    The state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.

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    26 PLASTIC

    User notes:

    About this chapter: The use of plastics in building construction and components is addressed in Chapter 26. This chapter provides standards addressing foam plastic insulation, foam plastics used as interior finish and trim, and other plastic veneers used on the inside or outside of a building. This chapter addresses the use of light-transmitting plastics in various configurations such as walls, roof panels, skylights, signs and glazing. Requirements for the use of fiber-reinforced polymers, fiberglass-reinforced polymers and reflective plastic core insulation are also contained in this chapter. Additionally, requirements specific to the use of wood-plastic composites and plastic lumber are contained in this chapter.

    SECTION 2601—GENERAL

    2601.1 Scope. These provisions shall govern the materials, design, application, construction and installation of foam plastic, foam plastic insulation, plastic veneer, interior plastic finish and trim, light-transmitting plastics and plastic composites, including plastic lumber.

    SECTION 2602—FINISH AND TRIM

    2602.1 Exterior wall covering and architectural trim. See Chapter 14 for requirements for exterior wall covering and architectural trim.

    2602.2 Interior finish and trim. See Section 2604 for requirements for interior finish and trim.

    SECTION 2603—FOAM PLASTIC INSULATION

    2603.1 General. The provisions of this section shall govern the requirements and uses of foam plastic insulation in buildings and structures.

    2603.1.1 Spray-applied foam plastic. Single- and multiple-component spray-applied foam plastic insulation shall comply with the provisions of Section 2603 and ICC 1100.

    2603.1.2 Insulating sheathing. Foam plastic materials used as insulating sheathing shall comply with the provisions of Section 2603 and the material standards in Table 2603.1.2.

    TABLE 2603.1.2—MATERIAL STANDARDS FOR FOAM PLASTIC INSULATING SHEATHING Col2
    MATERIAL STANDARD
    Expanded Polystyrene (EPS) ASTM C578
    Extruded Polystyrene (XPS) ASTM C578
    Polyisocyanurate ASTM C1289

    2603.2 Labeling and identification. Packages and containers of foam plastic insulation and foam plastic insulation components delivered to the job site shall bear the label of an approved agency showing the manufacturer’s name, product listing, product identification and information sufficient to determine that the end use will comply with the code requirements.

  • CBC § 2602.1 Medium relevance — show source text

    SECTION 2602—FINISH AND TRIM

    2602.1 Exterior wall covering and architectural trim. See Chapter 14 for requirements for exterior wall covering and architectural trim.

    2602.2 Interior finish and trim. See Section 2604 for requirements for interior finish and trim.

    SECTION 2603—FOAM PLASTIC INSULATION

    2603.1 General. The provisions of this section shall govern the requirements and uses of foam plastic insulation in buildings and structures.

    2603.1.1 Spray-applied foam plastic. Single- and multiple-component spray-applied foam plastic insulation shall comply with the provisions of Section 2603 and ICC 1100.

    2603.1.2 Insulating sheathing. Foam plastic materials used as insulating sheathing shall comply with the provisions of Section 2603 and the material standards in Table 2603.1.2.

    TABLE 2603.1.2—MATERIAL STANDARDS FOR FOAM PLASTIC INSULATING SHEATHING Col2
    MATERIAL STANDARD
    Expanded Polystyrene (EPS) ASTM C578
    Extruded Polystyrene (XPS) ASTM C578
    Polyisocyanurate ASTM C1289

    2603.2 Labeling and identification. Packages and containers of foam plastic insulation and foam plastic insulation components delivered to the job site shall bear the label of an approved agency showing the manufacturer’s name, product listing, product identification and information sufficient to determine that the end use will comply with the code requirements.

    2603.2.1 Labeling of polystyrene foam insulation without flame retardants . In addition to the requirements of Section 2603.2, polystyrene foam insulation boards manufactured with no flame retardants added shall be labeled in accordance with this section. 1. Each board shall be labeled on each face every 8 square feet in red [1] / 2 -inch text with the following information:

    WARNING - FIRE HAZARD

    This product is required to be installed below a minimum 3.5-inch-thick concrete slab on grade.

    NOT FOR VERTICAL OR ABOVE-GRADE APPLICATIONS

    This product contains NO flame retardants.

    Not tested for flame spread or smoke development requirements of the model building codes 2. Each package shall be labeled on at least two sides in red [1] / 2 -text with the following information:

    WARNING – COMBUSTIBLE MATERIAL

    Keep away from ignition sources.

    Maintain code required separation between product storage and structures under construction (minimum 30 feet).

    2603.3 Surface-burning characteristics. Unless otherwise indicated in this section, foam plastic insulation and foam plastic cores of manufactured assemblies shall have a flame spread index of not more than 75 and a smoke-developed index of not more than 450 where tested in the maximum thickness intended for use in accordance with ASTM E84 or UL 723. Loose fill-type foam plastic insulation shall be tested as board stock for the flame spread and smoke-developed indices.

    Exceptions:

    1. Smoke-developed index for interior trim as provided for in Section 2604.2.

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    PLASTIC

  • CBC § 7.1 Medium relevance — show source text

    Covering R703 Insulation finish systems R703.9 Lath R703.7.1

    Plaster R703.7 Exterior Insulation and Finish Systems (EIFS) 703.9

    Exterior Wall

    Construction R302.1

    Fire-resistance rating R302.1

    Factory Built Chimneys R1005 Fireplace stoves R1005.3 Fireplaces R1004 Fastening Table R602.3(1) Fees, Permit R108 Finishes Flame spread and smoke density R302.9 For ceilings R805 Interior R302.9, R311, R702 Fire Sprinkler System (see Automatic Sprinkler System) Ceiling configurations R309.3.4.1.1, R309.3.4.1.2, R309.3.4.1.3 Flow rate R309.3.4.1 Fireblocking Barrier between stories R302.11,

    R602.8 Chimney R1003.19 Fireplace R1001.12 Fireplaces Chapter 10 Clearance R1001.11 Corbeling R1001.8 Factory-built R1004 Fireblocking R1001.12 Walls R1001.5

    Fire-Resistant Construction R302 Draftstopping R302.2 Dwelling-garage fire separation R302.6 Dwelling-garage opening and penetration R302.5 Exterior walls R302.1 Fireblocking R302.11 Floors R302.13

    Foam plastics R302.8 Insulation R302.10, R302.14 Penetrations R302.4

    Townhouse separation R302.2 Two-family dwellings R302.3 Under-stair protection R302.7 Wall and ceiling finishes R302.9 Fire-Separation Distance Exterior walls and wall projections R302.1 Ground-mounted photovoltaic systems R329.7, R329.8 Fixtures

    Clearance R327.1

    Flood protection R306.1.6 Plumbing fixture, general R326, R327 Flame Spread Index R302.10, R302.9 Flashing R703.4, R703.8.5, R903.2, R905 Flood Protection Plan Areas protected by the facilities of Central Valley Appendix CK Flood-Resistant Construction

    General and structural R301.2.4, R306 Floors

    Bathtub and shower R327.2 Concrete (on ground) R506 Loads R301, R501.2 Steel framing R505 Treated wood (on ground) R504

    Wood framing R502 Flue

    Area R1003.14, R1003.15 Lining R1003.11, R1003.12 Multiple R1003.13 Foam Plastics R303 Footings R403 Foundations Chapter 4 Cripple walls R602.10.9, R602.11.2, R602.9

    Frost protection R403.1.4.1 Inspection R109.1.1 Walls R404

    Frame

  • CBC § 803.13 Medium relevance — show source text

    Interior finishes Table 803.13, 804 Live load Table 1607.1 Means of egress Corridors 1020.3

    Stairway, exit access 1019

    Travel distance 407, 1006.3, 1017.2,

    1006.2.1

    Mixed occupancies 508.3, 508.4 Occupancy exceptions 303.1.1, 303.1.2, 308.5.1, 308.5.4, 310.4.1 Plumbing fixtures Chapter 29 Risk category Table 1604.5 Standby, emergency power 2702.2 Insulation

    Concealed 720.2

    Duct insulation 720.1

    Exposed 720.3 Fiberboard 720.1, Table 1508.2, 2303.1.6.2, 2303.1.6.3 Foam plastic (see Foam Plastics) 720.1

    Loose fill 720.4, 720.6 Pipe insulation 720.1, 720.7 Reflective plastic core 2614 Roof 720.5, 1508 Sound 720, 807, 1206 Thermal 720, 807, 1508 Interior Environment Lighting 1204 Rodentproofing Appendix F Sound transmission 1206

    Space dimensions 1208 Temperature control 1203 Ventilation 409.3, 414.3, 415.9.1.7,

    1202.5

    Yards or courts 1205.2, 1205.3 Interior Finishes Chapter 8 Acoustical ceiling systems 807, 808 Application 803.13, 804.4 Atriums 404.8 Children’s play structures 424 Covered and open mall buildings 402.6

    Decorative materials 419, 802.3, 806 Floor finish 804, 805 Foam plastic insulation 2603.3, 2603.4 Foam plastic trim 806.6.1, 2604.2 Insulation 807 Light-transmitting plastics 2606 Signs 402.6.4, 2611 Site-fabricated stretch systems 803.10 Trim 806.6, 806.7 Wall and ceiling finishes 803 Wet location 1210 Intermodal Shipping Container 3114 Interpretation, Code 104.1

    Jails [see Institutional (see Group I-3)] 308.5, 408 Joint Gypsum board 2508.5 Lumber sheathing 2308.11.10 Waterproofing 1805.3.3 Joints, Fire-resistant Systems 715 Special inspection 1705.18

    Kiosks 402.6.2

    Kitchens 303.3, 306.2 Accessibility 1133A, 11B-212 Dimensions 1209 Means of egress 1016.2 Occupant load Table 1004.5 Sinks Chapter 29

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    INDEX

    Marquees 3106, H113 Construction 3106.5

  • CBC § 718.3.1 Medium relevance — show source text

    Particleboard 202 Draftstopping 718.3.1 Moisture protection 1402.2, 1404.2 Quality 2303.1.8 Veneer 1404.6 Wall bracing 2308.10.3 Partitions Fabric partition 1607.16.1 Fire (see Fire Partition) Live loads 1607.16, 1607.5 Materials 602.4, 603.1 Occupancy, specific 708.1 Smoke (see Smoke Partition) Toilets 1210 Party Walls (see Fire Walls) 706.1.1, Table 716.1(3) Passageway, Exit (See Exit) 1024 Passenger Stations 303.4 Passive Solar Energy Collector 202 Patio Covers 2606.10, Appendix I

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    INDEX

    Solar energy systems (see Solar Energy Systems) Pier Foundations (see Foundation, Shallow) Pile Foundations (see Foundation, Deep) Pipes Embedded in fire protection 704.7 Insulation covering 720.1, 720.7 Penetration protection 714, 1023.5 Under platform 410.3 Plan Review 107.3

    Plaster

    Fire-resistance requirements 719 Gypsum 719.1, 719.2 Inspection 110.3.6 Portland cement 719.5, Table 2507.2, Table 2511.1.1 Plastic Chapter 26 Approval for use 2606.2 Composites 2612 Core insulation, reflective plastic 2614 Decking 1410, 2612 Fiber-reinforced polymer 2613 Finish and trim, exterior 2602.1 Finish and trim, interior 2602, 2604 Light-transmitting panels 2401.1, 2607 Roof panels 2609 Signs D102.2.10, H107.1.1, 402.6.4, 2611

    Thermal barrier 2603.4

    Veneer D102.2.11, 2605 Walls, exterior 2603.4.1.4, 2603.5 Plastic, Foam Insulation (see Foam Plastics) 2603 Interior finish 803.4, 2603.9 Malls 402.6.2, 402.6.4.5 Play structures 424.2 Stages and platforms 410.2.6 Plastic, Light-transmitting Awnings and patio covers 2606.10 Bathroom accessories 2606.9

    Exterior wall panels 2607 Fiberglass-reinforced polymer 2613.4 Fiber-reinforced polymer 2613.4 Glazing 2608 Greenhouses 2609 Light-diffusing systems 2606.7 Roof panels 2609 Signs, interior 2611 Skylight 2610 Solar collectors 2606.12

  • CBC § 802.3 Medium relevance — show source text

    Decorative materials 419, 802.3, 806 Floor finish 804, 805 Foam plastic insulation 2603.3, 2603.4 Foam plastic trim 806.6.1, 2604.2 Insulation 807 Light-transmitting plastics 2606 Signs 402.6.4, 2611 Site-fabricated stretch systems 803.10 Trim 806.6, 806.7 Wall and ceiling finishes 803 Wet location 1210 Intermodal Shipping Container 3114 Interpretation, Code 104.1

    Jails [see Institutional (see Group I-3)] 308.5, 408 Joint Gypsum board 2508.5 Lumber sheathing 2308.11.10 Waterproofing 1805.3.3 Joints, Fire-resistant Systems 715 Special inspection 1705.18

    Kiosks 402.6.2

    Kitchens 303.3, 306.2 Accessibility 1133A, 11B-212 Dimensions 1209 Means of egress 1016.2 Occupant load Table 1004.5 Sinks Chapter 29

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    INDEX

    Marquees 3106, H113 Construction 3106.5

    Drainage, water 3201.4 Live load Table 1607.1, 1607.14 Prohibited location 3106.4

    Roof construction 3106.3 Masonry Chapter 21A Adhered veneer 1404.11

    Adobe 2109 Anchorage 1604.8.2 Anchored veneer 1404.7

    Architectural cast stone 2103.1

    Calculated fire resistance 722.4 Chimneys 2113 Construction 2104 Dampproofing 1805.2.2 Design, methods 2101.2, 2107, 2108, 2109

    Fire resistance, calculated 722.3.2,

    722.3.4

    Fireplaces 2111 Floor anchorage 1604.8.2 Foundation walls 1807.1.5

    Foundations, adobe 2109.2.4.5 Glass unit 2110

    Heaters 2112

    Inspection, special 1705.4 Joint reinforcement 2103.4

    Materials 603.1, 2103 Penetrations 714 Quality assurance 2105 Rodentproofing Appendix F Roof anchorage 1604.8.1 Seismic provisions 2106 Serviceability 1604.3.4 Supported by wood 2104.1.1, 2304.13 Surface bonding 2103.2.2 Veneer 1404.11, 1404.7, 2101.2.1,

    2308.10.10 Wall anchorage 1604.8.2 Waterproofing 1805.3.2 Mass Notification Systems 917 Mass Timber 508, 509, 602, 703, 718, 722 Materials

    Alternates 104.2.3

  • CBC § 2604.1 Medium relevance — show source text

    SECTION 2604—INTERIOR FINISH AND TRIM

    2604.1 General. Plastic materials installed as interior finish or trim shall comply with Chapter 8. Foam plastics shall only be installed as interior finish where approved in accordance with the special provisions of Section 2603.9. Foam plastics that are used as interior finish shall meet the flame spread and smoke-developed index requirements for interior finish in accordance with Chapter 8. Foam plastics installed as interior trim shall comply with Section 2604.2. 2604.1.1 Plenums. Foam plastics installed in plenums as interior wall or ceiling finish shall comply with Section 2603.7. Foam plastics installed in plenums as interior trim shall comply with Sections 2604.2 and 2603.7.

    [F] 2604.2 Interior trim. Foam plastic used as interior trim shall comply with Sections 2604.2.1 through 2604.2.4.

    [F] 2604.2.1 Density. The minimum density of the interior trim shall be 20 pcf (320 kg/m [3] ).

    [F] 2604.2.2 Thickness. The maximum thickness of the interior trim shall be [1] / 2 inch (12.7 mm) and the maximum width shall be 8 inches (204 mm).

    [F] 2604.2.3 Area limitation. The interior trim shall not constitute more than 10 percent of the specific wall or ceiling areas to which it is attached.

    [F] 2604.2.4 Flame spread. The flame spread index shall not exceed 75 where tested in accordance with ASTM E84 or UL 723. The smoke-developed index shall not be limited.

    Exception: Where the interior trim material has been tested as an interior finish in accordance with NFPA 286 and complies with the acceptance criteria in Section 803.1.1.1, it shall not be required to be tested for flame spread index in accordance with ASTM E84 or UL 723.

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    PLASTIC

    SECTION 2605—PLASTIC VENEER

    2605.1 Interior use. Where used within a building, plastic veneer shall comply with the interior finish requirements of Chapter 8.

    2605.2 Exterior use. Exterior plastic veneer, other than plastic siding, shall be permitted to be installed on the exterior walls of buildings of any type of construction in accordance with all of the following requirements:

    1. Plastic veneer shall comply with Section 2606.4.
    2. Plastic veneer shall not be attached to any exterior wall to a height greater than 50 feet (15 240 mm) above grade.
    3. Sections of plastic veneer shall not exceed 300 square feet (27.9 m [2] ) in area and shall be separated by not less than 4 feet (1219 mm) vertically.

    Exception: The area and separation requirements and the smoke-density limitation are not applicable to plastic veneer applied to buildings constructed of Type VB construction, provided that the walls are not required to have a fire-resistance rating.

    2605.3 Plastic siding. Plastic siding shall comply with the requirements of Sections 1403 and 1404.

    SECTION 2606—LIGHT-TRANSMITTING PLASTICS

  • CBC § 803.5.2 Medium relevance — show source text

    803.5.2 Acceptance criteria for wall and ceiling coverings. Textile wall and ceiling coverings shall have a Class A flame spread index in accordance with ASTM E84 or UL 723, and be protected by an automatic sprinkler system installed in accordance with Section 903.3.1.1 or 903.3.1.2. Test specimen preparation and mounting shall be in accordance with ASTM E2404.

    803.6 Textile ceiling coverings. Where used as interior ceiling finish materials, textile ceiling coverings, including materials having a woven, nonwoven, napped, tufted, looped or similar surface and carpet or similar textile materials, shall be tested in the manner intended for use, using the product mounting system, including adhesive, and shall comply with the requirements of Section 803.1.1 or 803.5.2.

    803.7 Expanded vinyl wall coverings. Where used as interior wall finish materials, expanded vinyl wall coverings shall be tested in the manner intended for use, using the product mounting system, including adhesive, and shall comply with the requirements of Section 803.1.1, 803.5.1 or 803.5.2.

    803.8 Expanded vinyl ceiling coverings. Where used as interior ceiling finish materials, expanded vinyl ceiling coverings shall be tested in the manner intended for use, using the product mounting system, including adhesive, and shall comply with the requirements of Section 803.1.1 or 803.5.2.

    [BF] 803.9 High-density polyethylene (HDPE) and polypropylene (PP). Where high-density polyethylene or polypropylene is used as an interior finish, it shall comply with Section 803.1.1.

    [BF] 803.10 Site-fabricated stretch systems. Where used as newly installed interior wall or interior ceiling finish materials, sitefabricated stretch systems containing all three components described in the definition in Chapter 2 shall be tested in the manner intended for use, and shall comply with the requirements of Section 803.1.1 or 803.1.2. If the materials are tested in accordance with ASTM E84 or UL 723, specimen preparation and mounting shall be in accordance with ASTM E2573.

    803.11 Foam plastic materials. Foam plastic materials shall not be used as interior wall and ceiling finish unless specifically allowed by Section 803.11.1 or 803.11.2. Foam plastic materials shall not be used as interior trim unless specifically allowed by Section 804.2.

    803.11.1 Foam plastics. Foam plastics shall be allowed to be used as interior wall and ceiling finish only where in accordance with Section 2603.9 of the California Building Code . This section shall apply both to exposed foam plastics and to foam plastics used in conjunction with a textile or vinyl facing or cover.

    803.11.2 Thermal barrier for foam plastics. Foam plastic material shall be allowed if it is separated from the interior of the building by a thermal barrier in accordance with Section 2603.4 of the California Building Code.

  • CBC § 806.4 Medium relevance — show source text

    [F] 806.4 Acceptance criteria and reports. Where required to exhibit improved fire performance, curtains, draperies, fabric hangings and similar combustible decorative materials suspended from walls or ceilings shall be tested by an approved agency and shall be flame resistant in accordance with the provisions set forth in CCR, Title 19, Division 1, Chapter 8 . Reports of test results shall be prepared in accordance with the test method used and furnished to the building official on request.

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    INTERIOR FINISHES

    [F] 806.5 Pyroxylin plastic. Imitation leather or other material consisting of or coated with a pyroxylin or similarly hazardous base shall not be used in Group A occupancies.

    [F] 806.6 Interior trim. Material, other than foam plastic used as interior trim, shall have a minimum Class B flame spread and 450 smoke-developed index in Group I-3 and for all other occupancies Class C flame spread and smoke-developed index when tested in accordance with ASTM E84 or UL 723, as described in Section 803.1.2. Combustible trim, excluding handrails and guardrails, shall not exceed 10 percent of the specific wall or ceiling area to which it is attached.

    [F] 806.6.1 Foam plastic. Foam plastic used as interior trim in any occupancy shall comply with Section 2604.2.

    [F] 806.7 Interior floor-wall base. Interior floor-wall base that is 6 inches (152 mm) or less in height shall be tested in accordance with Section 804.2 and shall be not less than Class II. Where a Class I floor finish is required, the floor-wall base shall be Class I.

    Exception: Interior trim materials that comply with Section 806.6.

    [F] 806.8 Combustible lockers. Where lockers constructed of combustible materials are used, the lockers shall be considered to be interior finish and shall comply with Section 803.

    Exception: Lockers constructed entirely of wood and noncombustible materials shall be permitted to be used wherever interior finish materials are required to meet a Class C classification in accordance with Section 803.1.2.

    SECTION 807—INSULATION

    807.1 Insulation. Thermal and acoustical insulation shall comply with Section 720.

    SECTION 808—ACOUSTICAL CEILING SYSTEMS

    808.1 Acoustical ceiling systems. The quality, design, fabrication and erection of metal suspension systems for acoustical tile and lay-in panel ceilings in buildings or structures shall conform to generally accepted engineering practice, the provisions of this chapter and other applicable requirements of this code.

    808.1.1 Materials and installation. Acoustical materials complying with the interior finish requirements of Section 803 shall be installed in accordance with the manufacturer’s recommendations and applicable provisions for applying interior finish.

    808.1.1.1 Suspended acoustical ceilings. Suspended acoustical ceiling systems shall be installed in accordance with the provisions of ASTM C635 and ASTM C636.

    808.1.1.2 Fire-resistance-rated construction. Acoustical ceiling systems that are part of fire-resistance-rated construction shall be installed in the same manner used in the assembly tested and shall comply with the provisions of Chapter 7.

  • CBC § 25-3 Medium relevance — show source text

    2503 Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25-3

    2504 Vertical and Horizontal Assemblies . . . . . . . . . . . . . . 25-4

    2505 Shear Wall Construction. . . . . . . . . . . . . . . . . . . . . . . . 25-4

    2506 Gypsum Panel Product Materials . . . . . . . . . . . . . . . . 25-4

    2507 Lathing and Plastering . . . . . . . . . . . . . . . . . . . . . . . . . 25-5

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    2508 Gypsum Construction . . . . . . . . . . . . . . . . . . . . . . . . . 25-6

    2509 Showers and Water Closets . . . . . . . . . . . . . . . . . . . . 25-7

    2510 Lathing and Furring for Cement Plaster (Stucco). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25-7

    2511 Interior Plaster. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25-8

    2512 Exterior Plaster . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25-9

    2513 Exposed Aggregate Plaster. . . . . . . . . . . . . . . . . . . . 25-10

    2514 Reinforced Gypsum Concrete . . . . . . . . . . . . . . . . . 25-10

    CHAPTER 26 PLASTIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26-1

    2601 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26-3

    2602 Finish and Trim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26-3

    2603 Foam Plastic Insulation. . . . . . . . . . . . . . . . . . . . . . . . 26-3

    2604 Interior Finish and Trim. . . . . . . . . . . . . . . . . . . . . . . . 26-7

    2605 Plastic Veneer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26-8

    2606 Light-Transmitting Plastics. . . . . . . . . . . . . . . . . . . . . 26-8

    2607 Light-Transmitting Plastic Wall Panels . . . . . . . . . . 26-9

  • CBC § 719.1 Medium relevance — show source text

    Fire-resistance requirements 719 Gypsum 719.1, 719.2 Inspection 110.3.6 Portland cement 719.5, Table 2507.2, Table 2511.1.1 Plastic Chapter 26 Approval for use 2606.2 Composites 2612 Core insulation, reflective plastic 2614 Decking 1410, 2612 Fiber-reinforced polymer 2613 Finish and trim, exterior 2602.1 Finish and trim, interior 2602, 2604 Light-transmitting panels 2401.1, 2607 Roof panels 2609 Signs D102.2.10, H107.1.1, 402.6.4, 2611

    Thermal barrier 2603.4

    Veneer D102.2.11, 2605 Walls, exterior 2603.4.1.4, 2603.5 Plastic, Foam Insulation (see Foam Plastics) 2603 Interior finish 803.4, 2603.9 Malls 402.6.2, 402.6.4.5 Play structures 424.2 Stages and platforms 410.2.6 Plastic, Light-transmitting Awnings and patio covers 2606.10 Bathroom accessories 2606.9

    Exterior wall panels 2607 Fiberglass-reinforced polymer 2613.4 Fiber-reinforced polymer 2613.4 Glazing 2608 Greenhouses 2609 Light-diffusing systems 2606.7 Roof panels 2609 Signs, interior 2611 Skylight 2610 Solar collectors 2606.12

    Structural requirements 2606.5 Unprotected openings 2608.1, 2608.2 Veneer, exterior 603.1, 2605 Wall panels 2607 Plastic Glazing 2401.1, 2405.5.2, 2406.1.2 Platform (see Stages and Platforms) 410 Construction 410.3

    Temporary 410.3.1 Platform, Equipment (see Equipment Platform) Platform Lifts, Wheelchair Accessibility Chapters 11A and 11B Accessible means of egress 1009.2, 1009.5, Chapters 11A and 11B, 2702.2 Play Structures 424 Accessibility Chapters 11A and 11B Covered and open mall building 402.6.3

    Pollutant Control 1212 Ponding Table 1604.3, 1607.14.3.5, 1608.3, 1611.2, 1611.3 Porcelain Tile 1404.11.2, Table 1404.2

    Prefabricated Wood I-Joist 2303.1, 2303.1.2, 2308.11.8 Prescriptive Fire Resistance 721 Preservative-treated Wood 202

  • CBC § 25-10 Medium relevance — show source text

    2513 Exposed Aggregate Plaster. . . . . . . . . . . . . . . . . . . . 25-10

    2514 Reinforced Gypsum Concrete . . . . . . . . . . . . . . . . . 25-10

    CHAPTER 26 PLASTIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26-1

    2601 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26-3

    2602 Finish and Trim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26-3

    2603 Foam Plastic Insulation. . . . . . . . . . . . . . . . . . . . . . . . 26-3

    2604 Interior Finish and Trim. . . . . . . . . . . . . . . . . . . . . . . . 26-7

    2605 Plastic Veneer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26-8

    2606 Light-Transmitting Plastics. . . . . . . . . . . . . . . . . . . . . 26-8

    2607 Light-Transmitting Plastic Wall Panels . . . . . . . . . . 26-9

    2608 Light-Transmitting Plastic Glazing . . . . . . . . . . . . . 26-10

    2609 Light-Transmitting Plastic Roof Panels . . . . . . . . . 26-10

    2610 Light-Transmitting Plastic Skylight Glazing . . . . . 26-11

    2611 Light-Transmitting Plastic Interior Signs. . . . . . . . 26-11

    2612 Plastic Composite Decking . . . . . . . . . . . . . . . . . . . . 26-12

    2613 Fiber-Reinforced Polymer. . . . . . . . . . . . . . . . . . . . . 26-12

    2614 Reflective Plastic Core Insulation . . . . . . . . . . . . . . 26-13

    CHAPTER 27 ELECTRICAL. . . . . . . . . . . . . . . . . . . . . . . . . . 27-1

    2701 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27-3

    2702 Emergency and Standby Power Systems . . . . . . . . 27-3

    2703 Lightning Protection Systems . . . . . . . . . . . . . . . . . . 27-4

    CHAPTER 28 MECHANICAL SYSTEMS . . . . . . . . . . . . . . . . 28-1

    2801 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28-3

Frequently asked questions

Can foam plastic be used as exposed interior finish?

Exposed foam plastics are generally prohibited as interior finish unless specifically allowed by the special‑approval routes in §2603.9 or by meeting the Chapter 8 performance/testing requirements (and, where required, being separated by a thermal barrier per §2603.4).

What flame‑spread and smoke limits apply to foam plastic insulation?

Foam plastic insulation and foam plastic cores must, unless otherwise noted, have a flame‑spread index not greater than 75 and a smoke‑developed index not greater than 450 when tested per ASTM E84/UL 723; special exceptions and alternate large‑scale tests are provided in the chapter.

Where are the acoustical ceiling and insulation installation rules?

Acoustical ceiling systems and insulation performance/installation requirements are in Sections 808 and 807 respectively; these sections reference ASTM installation standards and require compliance with Chapter 8 finish criteria where applicable.

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