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• IBC 2603.1

  General

  • General scope for Section 2603.

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.2

  Labeling and identification

  • Requirements for labeling and identification.

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.3

  Surface-burning characteristics

  • Foam plastic insulation has flame spread 75 or less and smoke 450 or less at the thickness used.

  Works withIRC R303.3IBC 2604.2IBC 903.3.1.1IBC 2603.9IBC 402.6.4

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.4

  Thermal barrier

  • Foam plastic is separated from the interior by a thermal barrier: ½ in gypsum, mass or heavy timber, or an NFPA 275 material.

  Works withIBC 718IRC R303.4IBC 2603.4.1IBC 2603.9IBC 2304.11

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.5

  Exterior walls of buildings of any height

  • Exterior walls with foam on Types I–IV meet 2603.5.1–2603.5.7 (rating, thermal barrier, potential heat, flame spread, NFPA 285, labels, ignition).

  Works withIBC 1402.5.5IBC 2603.5.1IBC 2603.5.7IBC 2603.2IBC 2603.3IBC 2603.4IBC 718.2

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.6

  Roofing

  • Requirements for roofing; see linked sections.

  Works withIBC 2603.2IBC 2603.3IBC 2603.4

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.7

  Foam plastic in plenums as interior finish or interior trim

  • Requirements for foam plastic in plenums as interior finish or interior trim; see linked sections.

  Works withIBC 803.1.1IBC 2603.9IBC 2603.4

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.8

  Protection against termites

  • In very heavy termite areas, no foam below grade on the outside of foundations or under slabs; 6 in clearance from soil above grade.

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.9

  Special approval

  • Foam may skip the thermal barrier when approved by large-scale tests (NFPA 286, FM 4880, UL 1040, UL 1715).

  Works withIRC R303.6IBC 2603.4IBC 2603.6IBC 803.1.1.1IBC Chapter 8

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.10

  Wind resistance

  • Foam sheathing on framed walls resists wind per ANSI/SBCA FS 100.

  Works withIRC R303.8IBC 2604

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.1.1

  Spray-applied foam plastic

  • Spray foam insulation meets 2603 and ICC 1100.

  Works withIRC R303.1IBC 2603

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.1.2

  Insulating sheathing

  • Requirements for insulating sheathing; see linked sections.

  Works withIBC 2603IBC Table 2603.1.2

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.4.1

  Thermal barrier not required

  • Requirements for thermal barrier not required; see linked sections.

  Works withIBC 2603.4IBC 2603.4.1.1IBC 2603.4.1.15

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.5.1

  Fire-resistance-rated walls

  • Requirements for fire-resistance-rated walls.

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.5.2

  Thermal barrier

  • Requirements for thermal barrier; see linked sections.

  Works withIBC 2603.4IBC 2603.9IBC 2603.4.1.4

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.5.3

  Potential heat

  • Requirements for potential heat; see linked sections.

  Works withIBC 2603.5.5IBC 2603.4.1.4

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.5.4

  Flame spread and smoke-developed indices

  • Foam, coatings and facings in exterior walls each have flame spread 25 or less, smoke 450 or less.

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.5.5

  Vertical and lateral fire propagation

  • Exterior wall assemblies with foam pass NFPA 285, except one-story IMP buildings and foam fully encased in 1 in of masonry or concrete.

  Works withIBC 1402.8IBC 2603.4.1.4

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.5.6

  Label required

  • Requirements for label required.

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.5.7

  Ignition

  • Exterior walls with foam show no sustained flaming in NFPA 268, unless faced with masonry, stucco, metal panels, fiber-cement or a thermal barrier.

  Works withIBC 2603.4IBC 2510IBC 1404.17IBC 1404.17.1IBC 1404.17.2

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.4.1.1

  Masonry or concrete construction

  • No thermal barrier where foam is covered by 1 in of masonry or concrete each side.

  Works withIRC R303.5.1

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.4.1.2

  Cooler and freezer walls

  • Requirements for cooler and freezer walls; see linked sections.

  Works withIBC 903.3.1.1

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.4.1.3

  Walk-in coolers

  • Requirements for walk-in coolers.

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.4.1.4

  Exterior walls, one-story buildings

  • Requirements for exterior walls, one-story buildings; see linked sections.

  Works withIBC 903.3.1.1

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.4.1.5

  Roofing

  • No thermal barrier for foam in a classified roof assembly over 0.47 in wood structural panel or tested to NFPA 276/UL 1256.

  Works withIRC R303.5.2

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.4.1.6

  Attics and crawl spaces

  • Service-only attics and crawl spaces: foam covered by an ignition barrier such as 1½ in mineral fiber, ¼ in wood panel, ⅜ in gypsum or 0.016 in steel.

  Works withIRC R303.5.3IRC R303.5.4

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.4.1.7

  Doors not required to have a fire protection rating

  • Requirements for doors not required to have a fire protection rating.

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.4.1.8

  Exterior doors in buildings of Group R-2 or R-3

  • Requirements for exterior doors in buildings of Group R-2 or R-3.

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.4.1.9

  Garage doors

  • Foam-core garage doors use metal or wood facings; dwelling garage doors need no thermal barrier.

  Works withIRC R303.5.5IBC 2603.3

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.4.1.10

  Siding backer board

  • Requirements for siding backer board.

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.4.1.11

  Interior trim

  • Requirements for interior trim; see linked sections.

  Works withIBC 2604

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.4.1.12

  Interior signs

  • Requirements for interior signs; see linked sections.

  Works withIBC 402.6.4IBC Chapter 8IFC

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.4.1.13

  Type V construction

  • Type V: spray foam at sills and rim joists up to 3¼ in, 1.5–2.0 pcf, flame spread 25 or less, may stay uncovered.

  Works withIRC R303.5.11

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.4.1.14

  Floors

  • Foam in floors needs no barrier on top under ½ in wood panel, but does underneath if exposed.

  Works withIRC R303.5.13IBC 2603.4

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 2603.4.1.15

  Separately controlled climate structures

  • Requirements for separately controlled climate structures.

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 803.4

  Foam plastics

  • Foam plastics as finish only per 2603.9.

  Works withIBC 2603.9

  International Building Code, 2024 · Chapter 8, Interior FinishesRead the full text (opens UpCodes in a new tab)

• IBC 1407.5

  Exterior walls of buildings of any height

  • Assemblies with EIFS meet 2603.5.

  Works withIBC 2603.5

  International Building Code, 2024 · Chapter 14, Exterior WallsRead the full text (opens UpCodes in a new tab)

• IBC 2613.5

  Exterior use

  • Exterior FRP meets 2603.5, unless limited to 20% of the wall with flame spread 25, or on buildings 40 ft or less with flame spread 200.

  Works withIBC 2603.5IBC 718IBC 718.2.6IBC 1405.1IBC 2614

  International Building Code, 2024 · Chapter 26, PlasticRead the full text (opens UpCodes in a new tab)

• IBC 410.2.6

  Scenery

  • Combustible scenery meets NFPA 701; foam plastics follow 2603.

  Works withIBC 806IBC 2603

  International Building Code, 2024 · Chapter 4, Special Detailed Requirements Based on Occupancy and UseRead the full text (opens UpCodes in a new tab)

• IBC 1406.12

  Foam plastic insulation

  • Assemblies with foam also meet 2603.

  Works withIBC 2603

  International Building Code, 2024 · Chapter 14, Exterior WallsRead the full text (opens UpCodes in a new tab)

• IBC 1408.13

  Foam plastic insulation

  • Systems with foam meet 2603.

  Works withIBC 2603

  International Building Code, 2024 · Chapter 14, Exterior WallsRead the full text (opens UpCodes in a new tab)

• IBC 1402.5.5

  Foam plastic insulation

  • Follow 2603.

  Works withIBC 2603

  International Building Code, 2024 · Chapter 14, Exterior WallsRead the full text (opens UpCodes in a new tab)

• IBC 1409.7.3

  Type I, II, III, and IV construction

  • Foam cores meet 2603.5; other combustible cores meet 1409.7.3.1–1409.7.3.4.

  Works withIBC 2603.5

  International Building Code, 2024 · Chapter 14, Exterior WallsRead the full text (opens UpCodes in a new tab)

• IBC 1409.9.1

  Foam plastic core

  • Per 2603.2 and 2603.5.6.

  Works withIBC 2603.2IBC 2603.5.6

  International Building Code, 2024 · Chapter 14, Exterior WallsRead the full text (opens UpCodes in a new tab)

• IBC 1409.7.1.1

  Foam plastic core

  • Per 2603.3.

  Works withIBC 2603.3

  International Building Code, 2024 · Chapter 14, Exterior WallsRead the full text (opens UpCodes in a new tab)

• IBC 1409.7.2.1

  Foam plastic core

  • Per 2603.4 unless approved under 2603.9.

  Works withIBC 2603.4IBC 2603.9

  International Building Code, 2024 · Chapter 14, Exterior WallsRead the full text (opens UpCodes in a new tab)

Searches all 4,276 IRC 2024 sections, 5,532 IBC 2024 sections and defined terms (Chapters 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33 so far) and each city's local rules as they are added. Section numbers and titles from the International Residential Code and International Building Code, 2024 editions, copyrighted by the International Code Council; the IRC's electrical chapters (34 to 43) follow NFPA 70, the National Electrical Code. Requirements are summarized in our words (IRC Chapters 3 to 43, IBC Chapters 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33); read the full text at the link on each result. Local values come from each city's published documents.