CBC · California Building Code

Exterior wall fire‑resistance, openings and fire‑separation distance (Table 705.5)

The CBC requires exterior walls to have a minimum fire‑resistance rating determined by Table 705.5 based on how far the wall is from adjacent property or building (fire‑separation distance), the building occupancy and the construction type. For walls less than or equal to 10 feet away the rating must be tested for exposure from both sides; parapets, joint protection, and limits on openings are tied to those ratings. Check §705.5 (and the table notes), §705.11 (duct/opening penetration rules) and §705.12 (parapet rules) for the exact requirements and exceptions filefile.

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Last reviewed: July 5, 2026

What the code requires — plain English

The California Building Code requires exterior walls to have a minimum fire‑resistance rating that depends on the fire‑separation distance (FSD = X), the occupancy group, and the type of construction; the specific required ratings are set in Table 705.5 and applied as required by §705.5. Where the FSD is ≤ 10 ft the rating must be for exposure from both sides; where the FSD is > 10 ft the rating may be for exposure from the inside only (§705.5) . Parapets, continuity of the rating and limitations on openings and penetrations are linked to these ratings (§705.6, §705.9, §705.11, §705.12) .

Requirements in detail

Key rule (controlling text)

  • The primary controlling provision is §705.5: exterior wall fire‑resistance ratings are determined from Table 705.5 based on FSD, occupancy and construction type; exposure direction requirements (both sides vs inside only) are set in §705.5 .
  • Table 705.5 (the table itself) contains the numeric hour ratings and the table notes that create important exceptions (see notes in Table 705.5) .

Decision‑relevant values (quick reference)

Fire separation distance (X) Type(s) of construction (typical grouping) Required exterior wall rating (hours) — example occupancy groups Code reference
X < 5 ft All types High‑hazard groups: 3 hr; mid groups: 2 hr; A/B/E etc.: 1 hr Table 705.5; §705.5
5 ≤ X < 10 ft IA, IVA He/L: 3 hr; F‑1/M/S‑1: 2 hr; A/B/E/etc.: 1 hr Table 705.5; §705.5
5 ≤ X < 10 ft Other types (IB/IIB/IIA/III/IV/V types not IA/IVA) He/L: 2 hr; F‑1/M/S‑1: 1 hr; A/B/E/etc.: 1 hr Table 705.5; §705.5
10 ≤ X < 30 ft IA, IB, IVA, IVB He/L: 2 hr; F‑1/M/S‑1: 1 hr; A/B/E/etc.: 1 hr (note c) Table 705.5; §705.5
10 ≤ X < 30 ft IIB, VB He/L: 1 hr; F‑1/M/S‑1: 0 hr; A/B/E/etc.: 0 hr Table 705.5; §705.5
X ≥ 30 ft All types 0 hr (no rating required) Table 705.5; §705.5

Notes: load‑bearing exterior walls must also comply with Table 601; the fire‑resistance rating is determined per exterior wall and per story (§705.5 notes) .

Exposure direction

  • If FSD ≤ 10 ft: required rating must be for exposure from both sides. If FSD > 10 ft: rating is required for exposure to fire from the inside only (§705.5) .
  • For occupancies regulated by the State Fire Marshal (Group A, E, H, I, L and R high‑rise and others listed in §1.11) the exterior wall rating must be for exposure from both sides regardless of FSD (§705.5) .

Continuity and extent of fire‑resistance

  • The wall’s fire‑resistance rating must extend from top of foundation or floor/ceiling below to one of the prescribed termination points (underside of sheathing/deck or underside of an equal/greater rated assembly when FSD > 10 ft) per §705.6 (continuity) .

Openings and area limits

  • The percent of wall area that may be openings (protected or unprotected) is controlled by §705.9.1 and Table 705.9; allowable openings are based on FSD and occupancy. When §705.9.1 permits unlimited unprotected openings (certain nonbearing walls), the required rating for the exterior wall is 0 hours (Table note) .
  • Openings that must be protected (when required) must use opening protectives per §705.9.2 and related sections (see table notes and §705.11 for duct/air‑transfer openings) .

Penetrations, ducts and joints

  • Penetrations by ducts and air‑transfer openings in exterior walls that are required to have protected openings must comply with the general penetration and shaft rules in §717 and §716 as applicable; §705.11 specifically points to §717 for ducts/air‑transfer openings and allows an exception for code‑required foundation vents (§705.11) .
  • Joints in fire‑resistance‑rated exterior walls must comply with §715; voids at intersections with curtain walls have special protection in §715.4 (§705.10) .

Parapets

  • Parapets are required on exterior walls in many cases; a parapet is not required where the wall is not required to be fire‑resistance‑rated per Table 705.5 or where other listed exceptions apply (§705.12) . See §705.12 for the full list of exceptions and related construction details (e.g., when one‑hour walls may terminate at underside of roof sheathing with specific roof framing/fire‑protection conditions) .

Exceptions & special cases

  • Group U private garage or carport only: exterior wall need not have a fire‑resistance rating where FSD is ≥ 5 ft; if the building is fully sprinklered per §903.3 the threshold is reduced to ≥ 3 ft (Table 705.5 notes) .
  • Group R‑3 in Type II‑B or Type V‑B: exterior wall need not be fire‑resistance rated where FSD ≥ 5 ft; if fully sprinklered the threshold reduces to ≥ 3 ft (Table 705.5 notes) .
  • Open parking garages complying with §406: may be exempted from having a fire‑resistance rating per table note c (see Table 705.5) .
  • Special occupancies (Group H, aircraft hangars S) and other specific conditions are handled elsewhere (§415.6, §412.3.1) and may impose different or additional requirements referenced in Table 705.5 notes .
  • When §705.9.1 allows nonbearing exterior walls with unlimited unprotected openings, the wall’s required rating is 0 hours (Table 705.5 note g) .

If a provision or condition you want to apply is not explicitly covered by the retrieved text above, I cannot invent additional exceptions — refer to the code official or the full CBC text for items not contained in the cited sections.

Common mistakes

  • Assuming the same rating applies regardless of story level: the required rating is determined for each exterior wall and the story in which it is located (§705.5, table note d) .
  • Forgetting exposure direction: using an “inside‑only” rating when FSD ≤ 10 ft (where the code requires both‑sided exposure) (§705.5) .
  • Neglecting Table 601: load‑bearing exterior walls may have additional rating requirements under Table 601 that must be applied in addition to Table 705.5 (§705.5 note a) .
  • Overlooking parapet requirements: if the wall is required to be rated under Table 705.5 a parapet may also be required unless an exception in §705.12 applies .
  • Mixing up opening area limits with wall rating: allowable percent openings are set in §705.9/Table 705.9, and those limits affect whether openings must be protected — do not assume rating alone controls openings .
  • Applying residential exemptions incorrectly: residential code (R‑sections) has some differing provisions — always check the CBC §705 family before mixing in residential code allowances (or confirm which code governs the project) .

Worked example — how to apply Table 705.5 with numbers

Scenario: Two‑story office building (Group B occupancy) of Type V‑B construction. An exterior wall face is 8 feet from the adjacent lot line (FSD X = 8 ft). No automatic sprinklers in the building.

Step 1 — find the X range: 5 ≤ X < 10 ft. Step 2 — find the construction grouping: Type V‑B falls into the “Others” row for the 5 ≤ X < 10 ft band in Table 705.5. Step 3 — find occupancy column: Group B is in the A/B/E/F‑2/I/Ri/S‑2/Unh column. Step 4 — read required rating from table: for 5 ≤ X < 10, “Others” row → the table entry for that occupancy column is 1 hour (see Table 705.5) — therefore the exterior wall must be 1‑hour fire‑resistance‑rated (§705.5, Table 705.5) . Step 5 — exposure direction: because X (8 ft) ≤ 10 ft the 1‑hour rating must be tested for exposure from both sides (§705.5) . Step 6 — check openings: allowable unprotected/protected opening area for that story must be checked in §705.9/Table 705.9; if openings exceed the allowable unprotected percent they must be protected with opening protectives per §705.9.2 (and duct/air openings per §705.11) . Step 7 — parapet: because the wall is required to be fire‑resistance‑rated, check §705.12 for parapet requirements and applicable exceptions; likely a parapet will be required unless another §705.12 exception applies .

Related provisions (direct CBC cross‑references)

  • §705.5 — Fire‑resistance ratings and Table 705.5 (primary controlling section) .
  • Table 705.5 — Fire‑resistance rating requirements (numerical table + notes) .
  • §705.6 — Continuity: how far the rating must extend vertically and parapet linkage .
  • §705.9 / Table 705.9 — Allowable area of openings in exterior walls by FSD and occupancy (affects protected/unprotected openings) .
  • §705.10 — Joints in rated exterior walls and void protection (§715 cross‑reference) .
  • §705.11 — Ducts and air‑transfer openings in rated exterior walls (requires compliance with §717) .
  • §705.12 — Parapets: required conditions and exceptions tied to exterior wall ratings and FSD .
  • Table 601 — Fire‑resistance for load‑bearing elements (applies in addition when exterior wall is load bearing) — see Table note a in Table 705.5 .

Code references

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

  • CBC § 705.9.1 High relevance — show source text

    Where Section 705.9.1 permits nonbearing exterior walls with unlimited area of unprotected openings, the required fire-resistance rating for the exterior walls is 0 hours.
    h. For a building containing only a Group U occupancy private garage or carport, the exterior wall shall not be required to have a fire-resistance rating where the fire separation
    distance is 5 feet (1523 mm) or greater_or where equipped throughout with an automatic sprinkler system in accordance with Section 903.3 the fire-resistance rating shall not be_
    required where the fire separation distance is 3 feet or greater.
    i. For a Group R-3 building of Type II-B or Type V-B construction, the exterior wall shall not be required to have a fire-resistance rating where the fire separation distance is 5 feet
    (1523 mm) or greater_ or where equipped throughout with an automatic sprinkler system in accordance with Section 903.3 the fire-resistance rating shall not be required where_
    the fire separation distance is 3 feet or greater.|For SI: 1 foot = 304.8 mm.
    a. Load-bearing exterior walls shall also comply with the fire-resistance rating requirements of Table 601.
    b. See Section 706.1.1 for party walls.
    c. Open parking garages complying with Section 406 shall not be required to have a fire-resistance rating.
    d. The fire-resistance rating of an exterior wall is determined based upon the fire separation distance of the exterior wall and the story in which the wall is located.
    e. For special requirements for Group H occupancies, see Section 415.6.
    f. For special requirements for Group S aircraft hangars, see Section 412.3.1.
    g. Where Section 705.9.1 permits nonbearing exterior walls with unlimited area of unprotected openings, the required fire-resistance rating for the exterior walls is 0 hours.
    h. For a building containing only a Group U occupancy private garage or carport, the exterior wall shall not be required to have a fire-resistance rating where the fire separation
    distance is 5 feet (1523 mm) or greater_or where equipped throughout with an automatic sprinkler system in accordance with Section 903.3 the fire-resistance rating shall not be_
    required where the fire separation distance is 3 feet or greater.
    i. For a Group R-3 building of Type II-B or Type V-B construction, the exterior wall shall not be required to have a fire-resistance rating where the fire separation distance is 5 feet
    (1523 mm) or greater_ or where equipped throughout with an automatic sprinkler system in accordance with Section 903.3 the fire-resistance rating shall not be required where_
    the fire separation distance is 3 feet or greater.|

    705.6 Continuity. The fire-resistance rating of exterior walls shall extend from the top of the foundation or floor/ceiling assembly below to one of the following:

    1. The underside of the floor sheathing, roof sheathing, deck or slab above.
    2. The underside of a floor/ceiling or roof/ceiling assembly having a fire-resistance rating equal to or greater than the exterior wall and the fire separation distance is greater than 10 feet.

    Parapets shall be provided as required by Section 705.12.

  • CBC § 705.4 High relevance — show source text

    However, opening protectives in such openings shall only be required in the exterior wall of the S-2 parking garage, not in the exterior wall openings in the R-2 building, and these opening protectives in the exterior wall of the S-2 parking garage shall be not less than 1 [1] / 2 -hour fire protection rating.

    705.4 Materials. Exterior walls shall be of materials permitted by the building’s type of construction.

    705.5 Fire-resistance ratings. For other than Group A, E, H, I, L and R occupancies, high-rise buildings, and other applications listed in Section 1.11 exterior walls shall be fire-resistance rated in accordance with Table 601, based on the type of construction, and Table 705.5, based on the fire separation distance. The required fire-resistance rating of exterior walls with a fire separation distance of greater than 10 feet (3048 mm) shall be rated for exposure to fire from the inside. The required fire-resistance rating of exterior walls with a fire separation distance of less than or equal to 10 feet (3048 mm) shall be rated for exposure to fire from both sides.

    For Group A, E, H, I, L and R occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal, exterior walls shall be fire-resistance rated in accordance with Tables 601 and 705.5 and this section. The required fire-resistance rating of exterior walls shall be rated for exposure to fire from both sides.

    2025 CALIFORNIA BUILDING CODE 7-7

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

    FIRE AND SMOKE PROTECTION FEATURES

    TABLE 705.5—FIRE-RESISTANCE RATING REQUIREMENTS FOR
    EXTERIOR WALLS BASED ON FIRE SEPARATION DISTANCE a, d, g    		 Col2 Col3 Col4 Col5
    ** FIRE SEPARATION**
    DISTANCE = X (feet)    		 ** TYPE OF CONSTRUCTION** ** OCCUPANCY GROUP He****_, L_** ** OCCUPANCY GROUP**
    F-1, M, S-1f    		 ** OCCUPANCY GROUP A, B,**
    E, F-2, I, Ri, S-2, Uh
    X < 5b All 3 2 1
    5 ≤ X < 10 IA, IVA 3 2 1
    5 ≤ X < 10 Others 2 1 1
    10 ≤ X < 30 IA, IB, IVA, IVB 2 1 1 c
    10 ≤ X < 30 IIB, VB 1 0 0
    10 ≤ X < 30 Others 1 1 1 c
    X ≥ 30 All 0 0 0
    For SI: 1 foot = 304.8 mm.
    a. Load-bearing exterior walls shall also comply with the fire-resistance rating requirements of Table 601.
    b. See Section 706.1.1 for party walls.
    c. Open parking garages complying with Section 406 shall not be required to have a fire-resistance rating.
    d. The fire-resistance rating of an exterior wall is determined based upon the fire separation distance of the exterior wall and the story in which the wall is located.
    e.
  • CBC § 304.8 High relevance — show source text

    For residential subdivisions where all dwellings and townhouses are equipped throughout with an automatic sprinkler system installed in accordance with Section_R309_, the fire
    separation distance for exterior walls not fire-resistance rated and for fire-resistance-rated projections shall be permitted to be reduced to 0 feet, and unlimited unprotected
    openings and penetrations shall be permitted, where the adjoining lot provides an open setback yard that is 6 feet or more in width on the opposite side of the property line.
    b. The fire-resistance rating shall be permitted to be reduced to 0 hours on the underside of the eave overhang if fireblocking is provided from the wall top plate to the underside
    of the roof sheathing.
    c. The fire-resistance rating shall be permitted to be reduced to 0 hours on the underside of the rake overhang where vent openings that communicate with the attic are not
    installed in the overhang or gable wall.|For SI: 1 foot = 304.8 mm.
    NA = Not Applicable.
    a. For residential subdivisions where all dwellings and townhouses are equipped throughout with an automatic sprinkler system installed in accordance with Section_R309_, the fire
    separation distance for exterior walls not fire-resistance rated and for fire-resistance-rated projections shall be permitted to be reduced to 0 feet, and unlimited unprotected
    openings and penetrations shall be permitted, where the adjoining lot provides an open setback yard that is 6 feet or more in width on the opposite side of the property line.
    b. The fire-resistance rating shall be permitted to be reduced to 0 hours on the underside of the eave overhang if fireblocking is provided from the wall top plate to the underside
    of the roof sheathing.
    c. The fire-resistance rating shall be permitted to be reduced to 0 hours on the underside of the rake overhang where vent openings that communicate with the attic are not
    installed in the overhang or gable wall.|For SI: 1 foot = 304.8 mm.
    NA = Not Applicable.
    a. For residential subdivisions where all dwellings and townhouses are equipped throughout with an automatic sprinkler system installed in accordance with Section_R309_, the fire
    separation distance for exterior walls not fire-resistance rated and for fire-resistance-rated projections shall be permitted to be reduced to 0 feet, and unlimited unprotected
    openings and penetrations shall be permitted, where the adjoining lot provides an open setback yard that is 6 feet or more in width on the opposite side of the property line.
    b. The fire-resistance rating shall be permitted to be reduced to 0 hours on the underside of the eave overhang if fireblocking is provided from the wall top plate to the underside
    of the roof sheathing.
    c. The fire-resistance rating shall be permitted to be reduced to 0 hours on the underside of the rake overhang where vent openings that communicate with the attic are not
    installed in the overhang or gable wall.|

    R302.2 Townhouses. Walls separating townhouse units shall be constructed in accordance with Section R302.2.1 or R302.2.2 and shall comply with Sections R302.2.3 through R302.2.5.

    R302.2.1 Double walls. Each townhouse unit shall be separated from other townhouse units by two 1-hour fire-resistance-rated wall assemblies tested in accordance with ASTM E119, UL 263 or Section 703.2.2 of the California Building Code.

    3-24 2025 CALIFORNIA RESIDENTIAL CODE

  • CBC § 705.5 High relevance — show source text
    TABLE 705.5—FIRE-RESISTANCE RATING REQUIREMENTS FOR
    EXTERIOR WALLS BASED ON FIRE SEPARATION DISTANCE a, d, g    		 Col2 Col3 Col4 Col5
    ** FIRE SEPARATION**
    DISTANCE = X (feet)    		 ** TYPE OF CONSTRUCTION** ** OCCUPANCY GROUP He****_, L_** ** OCCUPANCY GROUP**
    F-1, M, S-1f    		 ** OCCUPANCY GROUP A, B,**
    E, F-2, I, Ri, S-2, Uh
    X < 5b All 3 2 1
    5 ≤ X < 10 IA, IVA 3 2 1
    5 ≤ X < 10 Others 2 1 1
    10 ≤ X < 30 IA, IB, IVA, IVB 2 1 1 c
    10 ≤ X < 30 IIB, VB 1 0 0
    10 ≤ X < 30 Others 1 1 1 c
    X ≥ 30 All 0 0 0
    For SI: 1 foot = 304.8 mm.
    a. Load-bearing exterior walls shall also comply with the fire-resistance rating requirements of Table 601.
    b. See Section 706.1.1 for party walls.
    c. Open parking garages complying with Section 406 shall not be required to have a fire-resistance rating.
    d. The fire-resistance rating of an exterior wall is determined based upon the fire separation distance of the exterior wall and the story in which the wall is located.
    e. For special requirements for Group H occupancies, see Section 415.6.
    f. For special requirements for Group S aircraft hangars, see Section 412.3.1.
    g. Where Section 705.9.1 permits nonbearing exterior walls with unlimited area of unprotected openings, the required fire-resistance rating for the exterior walls is 0 hours.
    h. For a building containing only a Group U occupancy private garage or carport, the exterior wall shall not be required to have a fire-resistance rating where the fire separation
    distance is 5 feet (1523 mm) or greater_or where equipped throughout with an automatic sprinkler system in accordance with Section 903.3 the fire-resistance rating shall not be_
    required where the fire separation distance is 3 feet or greater.
    i. For a Group R-3 building of Type II-B or Type V-B construction, the exterior wall shall not be required to have a fire-resistance rating where the fire separation distance is 5 feet
    (1523 mm) or greater_ or where equipped throughout with an automatic sprinkler system in accordance with Section 903.3 the fire-resistance rating shall not be required where_
    the fire separation distance is 3 feet or greater.    		 For SI: 1 foot = 304.8 mm.
    a. Load-bearing exterior walls shall also comply with the fire-resistance rating requirements of Table 601.
    b. See Section 706.1.1 for party walls.
    c. Open parking garages complying with Section 406 shall not be required to have a fire-resistance rating.
    d. The fire-resistance rating of an exterior wall is determined based upon the fire separation distance of the exterior wall and the story in which the wall is located.
    e.
  • CBC § 415.6. High relevance — show source text

    For special requirements for Group H occupancies, see Section 415.6.
    f. For special requirements for Group S aircraft hangars, see Section 412.3.1.
    g. Where Section 705.9.1 permits nonbearing exterior walls with unlimited area of unprotected openings, the required fire-resistance rating for the exterior walls is 0 hours.
    h. For a building containing only a Group U occupancy private garage or carport, the exterior wall shall not be required to have a fire-resistance rating where the fire separation
    distance is 5 feet (1523 mm) or greater_or where equipped throughout with an automatic sprinkler system in accordance with Section 903.3 the fire-resistance rating shall not be_
    required where the fire separation distance is 3 feet or greater.
    i. For a Group R-3 building of Type II-B or Type V-B construction, the exterior wall shall not be required to have a fire-resistance rating where the fire separation distance is 5 feet
    (1523 mm) or greater_ or where equipped throughout with an automatic sprinkler system in accordance with Section 903.3 the fire-resistance rating shall not be required where_
    the fire separation distance is 3 feet or greater.|

    705.6 Continuity. The fire-resistance rating of exterior walls shall extend from the top of the foundation or floor/ceiling assembly below to one of the following:

    1. The underside of the floor sheathing, roof sheathing, deck or slab above.
    2. The underside of a floor/ceiling or roof/ceiling assembly having a fire-resistance rating equal to or greater than the exterior wall and the fire separation distance is greater than 10 feet.

    Parapets shall be provided as required by Section 705.12.

    705.7 Structural stability. Interior structural elements that brace the exterior wall but that are not located within the plane of the exterior wall shall have the minimum fire-resistance rating required in Table 601 for that structural element. Structural elements that brace the exterior wall but are located outside of the exterior wall or within the plane of the exterior wall shall have the minimum fireresistance rating required in Table 601 and Table 705.5 for the exterior wall.

    705.7.1 Floor assemblies in Type III construction. In Type III construction where a floor assembly supports gravity loads from an exterior wall, the fire-resistance rating of the portion of the floor assembly that supports the exterior wall shall be not less than the fire-resistance rating required for the exterior wall in Table 601. The fire-resistance rating provided by the portion of the floor assembly supporting and within the plane of the exterior wall shall be permitted to include the contribution of the ceiling membrane when considering exposure to fire from the inside. Where a floor assembly supports gravity loads from an exterior wall, the building elements of the floor construction within the plane of the exterior wall, including but not limited to rim joists, rim boards and blocking, shall be in accordance with the requirements for interior building elements of Type III construction.

    705.8 Unexposed surface temperature. Where protected openings are not limited by Section 705.9, the limitation on the rise of temperature on the unexposed surface of exterior walls as required by ASTM E119 or UL 263 shall not apply. Where protected openings are limited by Section 705.9, the limitation on the rise of temperature on the unexposed surface of exterior walls as required by ASTM E119 or UL 263 shall not apply provided that a correction is made for radiation from the unexposed exterior wall surface in accordance with the following formula:

  • CBC § 705.1 High relevance — show source text

    SECTION 705—EXTERIOR WALLS

    705.1 General. Exterior walls shall comply with this section.

    705.2 Projections. Cornices, eave overhangs, exterior balconies and similar projections extending beyond the exterior wall shall conform to the requirements of this section and Section 1405. Exterior egress balconies and exterior exit stairways and ramps shall comply with Sections 1021 and 1027, respectively. Projections shall not extend any closer to the line used to determine the fire separation distance than shown in Table 705.2.

    Exception: Buildings on the same lot and considered as portions of one building in accordance with Section 705.3 are not required to comply with this section for projections between the buildings.

    TABLE 705.2—MINIMUM DISTANCE OF PROJECTION Col2
    FIRE SEPARATION DISTANCE (FSD) (feet) MINIMUM DISTANCE FROM LINE USED TO DETERMINE FSD
    0 to less than 2 Projections not permitted
    2 to less than 3 24 inches
    3 to less than 5 Two-thirds of FSD
    5 or greater 40 inches
    For SI: 1 foot = 304.8 mm; 1 inch = 25.4 mm. For SI: 1 foot = 304.8 mm; 1 inch = 25.4 mm.

    705.2.1 Types I and II construction. Projections from walls of Type I or II construction shall be of noncombustible materials or combustible materials as allowed by Sections 705.2.3.1 and 705.2.4.

    705.2.2 Type III, IV or V construction. Projections from walls of Type III, IV or V construction shall be of any approved material.

    705.2.3 Projection protection. Projections extending to 5 feet (1524 mm) or less from the line used to determine the fire separation distance shall be one of the following:

    1. Noncombustible materials.

    2. Combustible materials of not less than 1-hour fire-resistance-rated construction.

    3. Heavy timber construction complying with Section 2304.11.

    4. Fire-retardant-treated wood.

    5. As permitted by Section 705.2.3.1.

    Exception: Type VB construction shall be allowed for combustible projections in Group R-3 and U occupancies with a fire separation distance greater than or equal to 5 feet (1524 mm).

    7-6 2025 CALIFORNIA BUILDING CODE

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

    FIRE AND SMOKE PROTECTION FEATURES

    705.2.3.1 Balconies and similar projections. Balconies and similar projections of combustible construction other than fireretardant-treated wood shall be fire-resistance rated where required by Table 601 for floor construction or shall be of heavy timber construction in accordance with Section 2304.11. The aggregate length of the projections shall not exceed 50 percent of the building’s perimeter on each floor.

  • CBC § 706.6.1. High relevance — show source text

    Values indicated are the percentage of the area of the exterior wall, per_story_.
    b. For the requirements for fire walls of buildings with differing heights, see Section 706.6.1.
    c. For openings in a fire wall for buildings on the same_lot_, see Section 706.8.
    d. The maximum percentage of unprotected and protected openings shall be 25 percent for Group R-3 occupancies.
    e. Unprotected openings shall not be permitted for openings with a fire separation distance of less than 15 feet for Group H-2 and H-3 occupancies.
    f. The area of unprotected and protected openings shall not be limited for Group R-3 occupancies, with a fire separation distance of 5 feet or greater.
    g. The area of openings in an open parking garage in accordance with Section 406.5 with a fire separation distance of 10 feet or greater shall not be limited.
    h. Includes buildings accessory to Group R-3.
    i. Not applicable to Group H-1, H-2 and H-3 occupancies.
    j. The area of openings in a building containing only a Group U occupancy private garage or carport with a fire separation distance of 5 feet or greater shall not be limited.
    k. For openings between S-2 parking garage and Group R-2 building, see Section 705.3, Exception 2.|For SI: 1 foot = 304.8 mm.
    UP, NS = Unprotected openings in buildings not equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1.
    UP, S = Unprotected openings in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1.
    P = Openings protected with an opening protective assembly in accordance with Section 705.9.2.
    a. Values indicated are the percentage of the area of the exterior wall, per_story_.
    b. For the requirements for fire walls of buildings with differing heights, see Section 706.6.1.
    c. For openings in a fire wall for buildings on the same_lot_, see Section 706.8.
    d. The maximum percentage of unprotected and protected openings shall be 25 percent for Group R-3 occupancies.
    e. Unprotected openings shall not be permitted for openings with a fire separation distance of less than 15 feet for Group H-2 and H-3 occupancies.
    f. The area of unprotected and protected openings shall not be limited for Group R-3 occupancies, with a fire separation distance of 5 feet or greater.
    g. The area of openings in an open parking garage in accordance with Section 406.5 with a fire separation distance of 10 feet or greater shall not be limited.
    h. Includes buildings accessory to Group R-3.
    i. Not applicable to Group H-1, H-2 and H-3 occupancies.
    j. The area of openings in a building containing only a Group U occupancy private garage or carport with a fire separation distance of 5 feet or greater shall not be limited.
    k. For openings between S-2 parking garage and Group R-2 building, see Section 705.3, Exception 2.|

    705.9.1 Allowable area of openings. The maximum area of unprotected and protected openings permitted in an exterior wall in any story of a building shall not exceed the percentages specified in Table 705.9 based on the fire separation distance of each individual story.

  • CBC § 412.3.1. High relevance — show source text

    For special requirements for Group S aircraft hangars, see Section 412.3.1.
    g. Where Section 705.9.1 permits nonbearing exterior walls with unlimited area of unprotected openings, the required fire-resistance rating for the exterior walls is 0 hours.
    h. For a building containing only a Group U occupancy private garage or carport, the exterior wall shall not be required to have a fire-resistance rating where the fire separation
    distance is 5 feet (1523 mm) or greater_or where equipped throughout with an automatic sprinkler system in accordance with Section 903.3 the fire-resistance rating shall not be_
    required where the fire separation distance is 3 feet or greater.
    i. For a Group R-3 building of Type II-B or Type V-B construction, the exterior wall shall not be required to have a fire-resistance rating where the fire separation distance is 5 feet
    (1523 mm) or greater_ or where equipped throughout with an automatic sprinkler system in accordance with Section 903.3 the fire-resistance rating shall not be required where_
    the fire separation distance is 3 feet or greater.|For SI: 1 foot = 304.8 mm.
    a. Load-bearing exterior walls shall also comply with the fire-resistance rating requirements of Table 601.
    b. See Section 706.1.1 for party walls.
    c. Open parking garages complying with Section 406 shall not be required to have a fire-resistance rating.
    d. The fire-resistance rating of an exterior wall is determined based upon the fire separation distance of the exterior wall and the story in which the wall is located.
    e. For special requirements for Group H occupancies, see Section 415.6.
    f. For special requirements for Group S aircraft hangars, see Section 412.3.1.
    g. Where Section 705.9.1 permits nonbearing exterior walls with unlimited area of unprotected openings, the required fire-resistance rating for the exterior walls is 0 hours.
    h. For a building containing only a Group U occupancy private garage or carport, the exterior wall shall not be required to have a fire-resistance rating where the fire separation
    distance is 5 feet (1523 mm) or greater_or where equipped throughout with an automatic sprinkler system in accordance with Section 903.3 the fire-resistance rating shall not be_
    required where the fire separation distance is 3 feet or greater.
    i. For a Group R-3 building of Type II-B or Type V-B construction, the exterior wall shall not be required to have a fire-resistance rating where the fire separation distance is 5 feet
    (1523 mm) or greater_ or where equipped throughout with an automatic sprinkler system in accordance with Section 903.3 the fire-resistance rating shall not be required where_
    the fire separation distance is 3 feet or greater.|For SI: 1 foot = 304.8 mm.
    a. Load-bearing exterior walls shall also comply with the fire-resistance rating requirements of Table 601.
    b. See Section 706.1.1 for party walls.
    c. Open parking garages complying with Section 406 shall not be required to have a fire-resistance rating.
    d. The fire-resistance rating of an exterior wall is determined based upon the fire separation distance of the exterior wall and the story in which the wall is located.
    e. For special requirements for Group H occupancies, see Section 415.6.
    f. For special requirements for Group S aircraft hangars, see Section 412.3.1.
    g.

  • CBC § 402.3 High relevance — show source text

    Exception: The permanent open space of 60 feet (18 288 mm) shall be permitted to be reduced to not less than 40 feet (12 192 mm), provided that the following requirements are met:

    1. The reduced open space shall not be allowed for more than 75 percent of the perimeter of the covered or open mall building and anchor buildings.

    2. The exterior wall facing the reduced open space shall have a fire-resistance rating of not less than 3 hours.

    3. Openings in the exterior wall facing the reduced open space shall have opening protectives with a fire protection rating of not less than 3 hours.

    4. Group E, H, I or R occupancies are not located within the covered or open mall building or anchor buildings.

    402.3 Lease plan. Each owner of a covered mall building or of an open mall building shall provide both the building and fire departments with a lease plan showing the location of each occupancy and its exits after the certificate of occupancy has been issued. Modifications or changes in occupancy or use from that shown on the lease plan shall not be made without prior approval of the building official.

    402.4 Construction. The construction of covered and open mall buildings, anchor buildings and parking garages associated with a mall building shall comply with Sections 402.4.1 through 402.4.3.

    402.4.1 Area and types of construction. The building area and type of construction of covered mall or open mall buildings, anchor buildings and parking garages shall comply with this section.

    402.4.1.1 Covered and open mall buildings. The building area of any covered mall or open mall building shall not be limited provided that the covered mall or open mall building does not exceed three floor levels at any point nor three stories above grade plane, and is of Type I, II, III or IV construction.

    402.4.1.2 Anchor buildings. The building area and building height of any anchor building shall be based on the type of construction as required by Section 503 as modified by Sections 504 and 506.

    Exception: The building area of any anchor building shall not be limited provided that the anchor building is not more than three stories above grade plane, and is of Type I, II, III or IV construction.

    2025 CALIFORNIA BUILDING CODE 4-5

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

    SPECIAL DETAILED REQUIREMENTS BASED ON OCCUPANCY AND USE

    402.4.1.3 Parking garage. The building area and building height of any parking garage shall be based on the type of construction as required by Sections 406.5 and 406.6, respectively.

    402.4.2 Fire-resistance-rated separation. Fire-resistance-rated separation is not required between tenant spaces and the mall. Fire-resistance-rated separation is not required between a food court and adjacent tenant spaces or the mall.

    402.4.2.1 Tenant separations. Each tenant space shall be separated from other tenant spaces by a fire partition complying with Section 708. A tenant separation wall is not required between any tenant space and the mall.

    402.4.2.2 Anchor building separation. An anchor building shall be separated from the covered or open mall building by fire walls complying with Section 706.

  • CBC § 2303.2 High relevance — show source text
    1. Combustible exterior wall coverings shall be limited to 40 feet (12 192 mm) in height above grade plane. Exceptions:
    2. Metal composite material (MCM) systems complying with Section 1406.
    3. Exterior insulation and finish systems (EIFS) complying with Section 1407.
    4. High-pressure decorative exterior-grade compact laminate (HPL) systems complying with Section 1408.
    5. Exterior wall coverings containing foam plastic insulation complying with Section 2603.
    6. Combustible exterior wall coverings constructed of fire-retardant-treated wood complying with Section 2303.2 for exterior installation shall not be limited in wall surface area where the fire separation distance is 5 feet (1524 mm) or less and shall be permitted up to 60 feet (18 288 mm) in height above grade plane regardless of the fire separation distance.
    7. Wood veneers shall comply with Section 1404.6.

    1405.1.1.1 Ignition resistance. Where permitted by Section 1405.1.1, combustible exterior wall coverings shall be tested in accordance with NFPA 268.

    Exceptions:

    1. Wood or wood-based products.
    2. Other combustible materials covered with an exterior weather covering, other than vinyl sidings, included in and complying with the thickness requirements of Table 1404.2.
    3. Aluminum having a minimum thickness of 0.019 inch (0.48 mm).

    1405.1.1.1.1 Fire separation 5 feet or less. Where installed on exterior walls having a fire separation distance of 5 feet (1524 mm) or less, combustible exterior wall coverings shall not exhibit sustained flaming as defined in NFPA 268.

    1405.1.1.1.2 Fire separation greater than 5 feet. For fire separation distances greater than 5 feet (1524 mm), any exterior wall covering shall be permitted that has been exposed to a reduced level of incident radiant heat flux in accordance with the NFPA 268 test method without exhibiting sustained flaming. The minimum fire separation distance required for the exterior wall covering shall be determined from Table 1405.1.1.1.2 based on the maximum tolerable level of incident radiant heat flux that does not cause sustained flaming of the exterior wall covering.

    14-16 2025 CALIFORNIA BUILDING CODE

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

    EXTERIOR WALLS

Frequently asked questions

What determines the required fire‑resistance rating for an exterior wall?

Table 705.5 sets the required rating based on the fire‑separation distance (X), the occupancy group, and the type of construction; apply §705.5 and the table notes to your wall and story to get the exact hours required file.

If my building is fully sprinklered, can the required rating be reduced?

Yes — Table 705.5 notes include specific reductions for certain occupancies (for example some Group U or R‑3 situations); check the table notes and the occupancy‑specific text in §705.5 for the exact conditions and thresholds .

Do I need a parapet if the exterior wall has a required rating?

Often yes: §705.12 requires parapets on exterior walls unless one of the listed exceptions applies (including situations where the wall isn’t required to be rated per Table 705.5) .

How does fire‑separation distance influence whether the rating is tested for both‑sided exposure?

§705.5 requires ratings for both sides when FSD ≤ 10 ft; when FSD > 10 ft the required rating (if any) is for exposure on the inside only, except where State Fire Marshal occupancies override this requirement and always need both‑sided exposure ratings .

Are openings in the exterior wall governed by the same table?

No — the maximum area of openings (protected and unprotected) is controlled by §705.9 and Table 705.9, which must be checked in addition to Table 705.5; if openings exceed allowable unprotected percentages they must be protected with opening protectives per the code .

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