CBC · California Building Code
Types of Construction
Chapter 6 of the CBC defines five construction types and their required fire‑resistance ratings (Table 601) that drive height, area and protection requirements across the code.
Last reviewed: July 5, 2026
Overview
Chapter 6 of the California Building Code establishes the five classifications of construction used to evaluate fire performance, materials and minimum fire‑resistance of building elements; these classifications (Types I–V) determine many design limits and protections required elsewhere in the CBC, including height and area controls in Chapter 5 and the general scope in §601 and §602.1 as the starting point for classification.
The required fire‑resistance ratings for structural frames, walls, floors and other elements are tabulated in Table 601 and are applied in conjunction with exterior‑wall ratings in Table 705.5; higher‑rated construction (Type I) generally allows greater height/area while Type V requires the least fire‑resistance. Specific rules for combustible materials in otherwise noncombustible Type I/II buildings and mass‑timber provisions for Type IV are addressed in §603 and §602.4 respectively.
In this section
Code references
Grounded in the retrieved California Building Code — click a citation to read the verbatim passage:
CBC § 509.1 High relevance — show source text
Unique consideration is taken for special use areas, such as covered mall buildings, motor-vehicle-related occupancies, special amusement buildings and aircraftrelated occupancies. Special facilities within other occupancies are considered, such as stages and platforms, motion picture projection rooms, children’s play structures and storm shelters. Finally, in order that the overall package of protection features can be easily understood, unique considerations for specific occupancies are also addressed.
Chapter 5 General Building Heights and Areas.
Chapter 5 contains the provisions that regulate the minimum type of construction for area limits and height limits based on the occupancy of the building. Height and area increases are permitted based on open frontage for fire department access, separation and the type of sprinkler protection provided (Sections 503 through 506, 510). Provisions include the protection and/or separation of incidental uses (Table 509.1), accessory occupancies (Section 508.2) and mixed uses in the same building (Sections 506.2.2, 508.3, 508.4 and 510). Unlimited area buildings are permitted in certain occupancies when they meet special provisions (Section 507). Live/work units are provided for in Section 508.5.
Tables 504.3, 504.4 and 506.2 are the keystones in setting thresholds for building size based on the building’s use and the materials with which it is constructed. Respective to each group classification, the greater the fire-resistance rating of structural elements, as represented by the type of construction, the greater the floor area and height allowances. The greater the potential fire hazards indicated as a function of the group, the lesser the height and area allowances for a particular construction type.
Chapter 6 Types of Construction.
The interdependence of fire safety considerations can be seen by looking at Tables 601 and 705.5, which show the fire-resistance ratings of the principal structural elements comprising a building in relation to the five classifications for types of construction. Type I construction generally requires the highest fire-resistance ratings for structural elements, whereas Type V construction generally requires the least amount of fire-resistance-rated structural elements. The greater the potential fire hazards indicated as a function of the group, the lesser the height and area allowances for a particular construction type. Section 603 includes a list of combustible elements that can be part of a noncombustible building (Types I and II construction).
2025 CALIFORNIA BUILDING CODE xiii
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
Chapter 7 Fire and Smoke Protection Features.
Chapter 7 provisions present the fundamental concepts of fire performance that all buildings are expected to achieve in some form. This chapter identifies the acceptable materials, techniques and methods by which proposed construction can be designed and evaluated against to determine a building’s ability to limit the impact of fire.
Chapter 7A Materials and Construction Methods for Exterior Wildfire Exposure.
Requirements for Wildland-Urban Interface Areas are now located in Part 7 of Title 24, California Wildland-Urban Interface Code. The provisions of Part 7, California Wildland-Urban Interface Code, shall apply to buildings and structures located in the wildland-urban interface (WUI) or Fire Hazard Severity Zone.
Chapter 8 Interior Finishes.
Chapter 8 contains the performance requirements for controlling fire growth within buildings by restricting interior finish and decorative materials. The provisions of Chapter 8 require materials used as interior finishes and decorations to meet certain flame-spread index or flame-propagation criteria based on the relative fire hazard associated with the occupancy.
Chapter 9 Fire Protection and Life Safety Systems.
CBC § 602.1 High relevance — show source text
602.1 General. Buildings and structures erected or to be erected, altered or extended in height or area shall be classified in one of the five construction types defined in Sections 602.2 through 602.5. The building elements shall have a fire-resistance rating not less than that specified in Table 601 and exterior walls shall have a fire-resistance rating not less than that specified in Table 705.5. Where required to have a fire-resistance rating by Table 601, building elements shall comply with the applicable provisions of Section 703.2.
2025 CALIFORNIA BUILDING CODE 6-3
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
TYPES OF CONSTRUCTION
The protection of openings, ducts and air transfer openings in building elements shall not be required unless required by other provisions of this code.
Exception: Noncombustible structural members supporting solar photovoltaic panels are not required to meet the fire resistance rating for the following: 1. Photovoltaic panel supported by a structure and having no use underneath. Signs may be provided, as determined by the enforcing agency prohibiting any use underneath including storage. 2. Solar photovoltaic (PV) panels supported by noncombustible framing that have sufficient uniformly distributed and unob- structed openings throughout the top of the array (horizontal plane) to allow heat and gases to escape, as determined by the enforcing agency. 3. Solar photovoltaic panels supported by a structure over parking stalls where the panels constitute the roof and all the following conditions are met (see Figure 5-1): 3.1. The area within the perimeter of the solar photovoltaic array has maximum rectangular dimension of 40 feet by 150 feet.
3.2. The distance between solar photovoltaic array structures is a minimum of 10 feet clear. 3.3. The driveway aisle separating solar photovoltaic array structures has a minimum width of 25 feet clear. 3.4. Solar photovoltaic array structure is used only for parking purposes with no storage. 3.5. Completely open on all sides (other than necessary structural supports) with no interior partitions.
602.1.1 Minimum requirements. A building or portion thereof shall not be required to conform to the details of a type of construction higher than that type which meets the minimum requirements based on occupancy even though certain features of such a building actually conform to a higher type of construction.
602.2 Types I and II. Types I and II construction are those types of construction in which the building elements specified in Table 601 are of noncombustible materials, except as permitted in Section 603 and elsewhere in this code.
602.3 Type III. Type III construction is that type of construction in which the exterior walls are of noncombustible materials and the interior building elements are of any material permitted by this code. Fire-retardant-treated wood framing and sheathing complying with Section 2303.2 shall be permitted within exterior wall assemblies of a 2-hour rating or less.
602.4 Type IV. Type IV construction is that type of construction in which the building elements are mass timber or noncombustible materials and have fire-resistance ratings in accordance with Table 601. Mass timber elements shall meet the fire-resistance-rating requirements of this section based on either the fire-resistance rating of the noncombustible protection, the mass timber, or a combination of both and shall be determined in accordance with Section 703.2.
CBC § 4.1.5 High relevance — show source text
4.1.5||||X|X|||||||||||||||||||| |602.4.2.5||||X|X|||||||||||||||||||| |602.4.3.5||||X|X|||||||||||||||||||| |602.4.4.3||||X|X|||||||||||||||||||| |603.1||||X|X|||||||||||||||||||| |603.1.3||||X|X||||||||||||||||||||
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.
2025 CALIFORNIA BUILDING CODE 6-1
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
6-2 2025 CALIFORNIA BUILDING CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
6 TYPES OF CONSTRUCTION
User notes:
About this chapter: Chapter 6 establishes five types of construction in which each building must be categorized. This chapter looks at the materials used in the building (combustible or noncombustible) and the extent to which building elements such as the building frame, roof, wall and floor can resist fire. Depending on the type of construction and the specific building element, fire resistance of 1 to 3 hours is specified.
ICC code development note: Code change proposals to sections in this chapter will be considered by one of the code development committees meeting during the 2025 (Group B) Code Development Cycle.
SECTION 601—GENERAL
TABLE 601—FIRE-RESISTANCE RATING REQUIREMENTS FOR BUILDING ELEMENTS (HOURS) Col2 Col3 Col4 Col5 Col6 Col7 Col8 Col9 Col10 Col11 Col12 Col13 BUILDING ELEMENT TYPE I TYPE I TYPE II TYPE II TYPE III TYPE III TYPE IV TYPE IV TYPE IV TYPE IV TYPE V TYPE V BUILDING ELEMENT A B A B A B A B C HT A B Primary structural framef
(see Section 202)3a, b 2a, b, c 1b, c 0c 1b, c 0 3a 2a 2a HT 1b, c 0 Bearing walls Exteriore, f 3 2 1 0 2 2 3 2 2 2 1 0 Interior 3a 2a 1 0 1 0 3 2 2 1/HTg 1 0 Nonbearing walls and partitions
ExteriorSee Table 705.5 See Table 705.5 See Table 705.5 See Table 705.5 See Table 705.5 See Table 705.5 See Table 705.5 See Table 705.5 See Table 705.5 See Table 705.5 See Table 705. CBC § 602.4.1.5 High relevance — show source text
Adopting agency BSC BSC-
CGSFM HCD Col6 Col7 DSA Col9 Col10 OSHPD Col12 Col13 Col14 Col15 Col16 Col17 BSCC DPH AGR DWR CEC CA SL SLC Adopting agency BSC BSC-
CGSFM 1 2 1/AC AC SS SS/CC 1 1R 2 3 4 5 6 6 6 6 6 6 6 6 6 Adopt entire chapter X X X X X X X X X X Adopt entire chapter as
amended (amended sections
listed below)X X X Adopt only those sections
that are listed belowChapter / Section Table 601 X 602.1 X Table 602 X 602.4.1.5 X X 602.4.2.5 X X 602.4.3.5 X X 602.4.4.3 X X 603.1 X X 603.1.3 X X 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.
2025 CALIFORNIA BUILDING CODE 6-1
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
6-2 2025 CALIFORNIA BUILDING CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
6 TYPES OF CONSTRUCTION
User notes:
About this chapter: Chapter 6 establishes five types of construction in which each building must be categorized. This chapter looks at the materials used in the building (combustible or noncombustible) and the extent to which building elements such as the building frame, roof, wall and floor can resist fire. Depending on the type of construction and the specific building element, fire resistance of 1 to 3 hours is specified.
ICC code development note: Code change proposals to sections in this chapter will be considered by one of the code development committees meeting during the 2025 (Group B) Code Development Cycle.
SECTION 601—GENERAL
CBC § 704.9 High relevance — show source text
704.9 Exterior structural members. Load-bearing structural members located within the exterior walls or on the outside of a building or structure shall be provided with the highest fire-resistance rating as determined in accordance with the following:
- As required by Table 601 for the type of building element based on the type of construction of the building.
- As required by Table 601 for exterior bearing walls based on the type of construction.
- As required by Table 705.5 for exterior walls based on the fire separation distance.
704.10 Bottom flange protection. Fire protection is not required at the bottom flange of lintels, shelf angles and plates, spanning not more than 6 feet 4 inches (1931 mm) whether part of the primary structural frame or not, and from the bottom flange of lintels, shelf angles and plates not part of the structural frame, regardless of span.
704.11 Seismic isolation systems. Fire-resistance ratings for the isolation system shall meet the fire-resistance rating required for the columns, walls or other structural elements in which the isolation system is installed in accordance with Table 601. Isolation systems required to have a fire-resistance rating shall be protected with approved materials or construction assemblies designed to provide the same degree of fire resistance as the structural element in which the system is installed when tested in accordance with ASTM E119 or UL 263 (see Section 703.2).
Such isolation system protection applied to isolator units shall be capable of retarding the transfer of heat to the isolator unit in such a manner that the required gravity load-carrying capacity of the isolator unit will not be impaired after exposure to the standard time-temperature curve fire test prescribed in ASTM E119 or UL 263 for a duration not less than that required for the fire-resistance rating of the structure element in which the system is installed.
Such isolation system protection applied to isolator units shall be suitably designed and securely installed so as not to dislodge, loosen, sustain damage or otherwise impair its ability to accommodate the seismic movements for which the isolator unit is designed and to maintain its integrity for the purpose of providing the required fire-resistance protection.
704.12 Sprayed fire-resistive materials (SFRM). Sprayed fire-resistive materials (SFRM) shall comply with Sections 704.12.1 through 704.12.5.
704.12.1 Fire-resistance rating. The application of SFRM shall be consistent with the fire-resistance rating and the listing, including, but not limited to, minimum thickness and dry density of the applied SFRM, method of application, substrate surface conditions and the use of bonding adhesives, sealants, reinforcing or other materials.
2025 CALIFORNIA BUILDING CODE 7-5
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
FIRE AND SMOKE PROTECTION FEATURES
704.12.2 Manufacturer’s installation instructions. The application of SFRM shall be in accordance with the manufacturer’s installation instructions. The instructions shall include, but are not limited to, substrate temperatures and surface conditions and SFRM handling, storage, mixing, conveyance, method of application, curing and ventilation.
704.12.3 Substrate condition. The SFRM shall be applied to a substrate in compliance with Sections 704.12.3.1 and 704.12.3.2.
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, gCol2 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, UhX < 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 § 2.2 High relevance — show source text
D101.2.2 Buffer zone. Where four contiguous blocks or more comprise a fire district, there shall be a buffer zone of 200 feet (60 960 mm) around the perimeter of such district. Streets, rights-of-way and other open spaces not subject to building construction can be included in the 200- foot (60 960 mm) buffer zone.
D101.2.3 Developed blocks. Where blocks adjacent to the fire district have developed to the extent that not less than 25 percent of the ground area is built upon and 40 percent or more of the built-on area is devoted to the occupancies specified in Section D101.2.1, they can be considered for inclusion in the fire district, and can form all or a portion of the 200-foot (60 960 mm) buffer zone required in Section D101.2.2.
SECTION D102—BUILDING RESTRICTIONS
D102.1 Types of construction permitted. Within the fire district every building hereafter erected shall be Type I, II, III or IV, except as permitted in Section D104.
D102.2 Other specific requirements.
D102.2.1 Exterior walls. Exterior walls of buildings located in the fire district shall comply with the requirements in Table 601 except as required in Section D102.2.6.
D102.2.2 Group H prohibited. Group H occupancies shall be prohibited from location within the fire district.
D102.2.3 Construction type. Every building shall be constructed as required based on the type of construction indicated in Chapter 6.
D102.2.4 Roof covering. Roof covering in the fire district shall conform to the requirements of Class A or B roof coverings as defined in Section 1505.
D102.2.5 Structural fire rating. Walls, floors, roofs and their supporting structural members shall be not less than 1-hour fireresistance-rated construction.
Exceptions:
- Buildings of Type IV-HT construction.
- Buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1.
- Automobile parking structures.
- Buildings surrounded on all sides by a permanently open space of not less than 30 feet (9144 mm).
- Partitions complying with Section 603.1, Item 11.
APPENDIX D-2 2025 CALIFORNIA BUILDING CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
APPENDIX D—FIRE DISTRICTS
D102.2.6 Exterior walls. Exterior load-bearing walls of Type II buildings shall have a fire-resistance rating of 2 hours or more where such walls are located within 30 feet (9144 mm) of a common property line or an assumed property line. Exterior nonloadbearing walls of Type II buildings located within 30 feet (9144 mm) of a common property line or an assumed property line shall have fire-resistance ratings as required by Table 601, but not less than 1 hour. Exterior walls located more than 30 feet (9144 mm) from a common property line or an assumed property line shall comply with Table 601. Exception: In the case of one-story buildings that are 2,000 square feet (186 m [2] ) or less in area, exterior walls located more than 15 feet (4572 mm) from a common property line or an assumed property line need only comply with Table 601.
CBC § 2.1 High relevance — show source text
Fire-retardant-treated wood members shall be
allowed to be used for such unprotected members.
2. For Group A, E, I, L, R-1, R-2 and R-2.1 occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal, fire protec-
tion of members other than the primary structural frame shall not be required, including protection of roof framing and decking where every part of the roof construction is 20
feet or more above any floor immediately below. Fire-retardant-treated wood members shall be allowed to be used for such unprotected members.
3. One-story portions of Group A and E assembly occupancies the roof-framing system of Type II A or Type III A construction may be of unprotected construction when such roof-
framing system is open to the assembly area and does not contain concealed spaces.
c. In all occupancies, heavy timber complying with Section 2304.11 shall be allowed for roof construction, including primary structural frame members, where a 1-hour or less
fire-resistance rating is required.
d. Not less than the fire-resistance rating required by other sections of this code.
e. Not less than the fire-resistance rating based on fire separation distance (see Table 705.5).
f. Not less than the fire-resistance rating as referenced in Section 704.9.
g. Heavy timber bearing walls supporting more than two floors or more than a floor and a roof shall have a fire-resistance rating of not less than 1 hour.|601.1 Scope. The provisions of this chapter shall control the classification of buildings as to type of construction.
SECTION 602—CONSTRUCTION CLASSIFICATION
602.1 General. Buildings and structures erected or to be erected, altered or extended in height or area shall be classified in one of the five construction types defined in Sections 602.2 through 602.5. The building elements shall have a fire-resistance rating not less than that specified in Table 601 and exterior walls shall have a fire-resistance rating not less than that specified in Table 705.5. Where required to have a fire-resistance rating by Table 601, building elements shall comply with the applicable provisions of Section 703.2.
2025 CALIFORNIA BUILDING CODE 6-3
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
TYPES OF CONSTRUCTION
The protection of openings, ducts and air transfer openings in building elements shall not be required unless required by other provisions of this code.
Exception: Noncombustible structural members supporting solar photovoltaic panels are not required to meet the fire resistance rating for the following: 1. Photovoltaic panel supported by a structure and having no use underneath. Signs may be provided, as determined by the enforcing agency prohibiting any use underneath including storage. 2. Solar photovoltaic (PV) panels supported by noncombustible framing that have sufficient uniformly distributed and unob- structed openings throughout the top of the array (horizontal plane) to allow heat and gases to escape, as determined by the enforcing agency. 3. Solar photovoltaic panels supported by a structure over parking stalls where the panels constitute the roof and all the following conditions are met (see Figure 5-1): 3.1. The area within the perimeter of the solar photovoltaic array has maximum rectangular dimension of 40 feet by 150 feet.
CBC § 705.3 Medium relevance — show source text
Exception: Fire-retardant-treated wood shall be permitted on buildings three stories or less above grade plane of Type I, II, III or IV construction.
705.3 Buildings on the same lot. For the purposes of determining the required wall and opening protection, projections and roofcovering requirements, buildings on the same lot shall be assumed to have an imaginary line between them.
Where a new building is to be erected on the same lot as an existing building, the location of the assumed imaginary line with relation to the existing building shall be such that the exterior wall and opening protection of the existing building meet the criteria as set forth in Sections 705.5 and 705.9.
Exceptions:
- Two or more buildings on the same lot shall be either regulated as separate buildings or shall be considered as portions of one building if the aggregate area of such buildings is within the limits specified in Chapter 5 for a single building. Where the buildings contain different occupancy groups or are of different types of construction, the area shall be that allowed for the most restrictive occupancy or construction.
- Where an S-2 parking garage of Construction Type I or IIA is erected on the same lot as a Group R-2 building, and there is no fire separation distance between these buildings, then the adjoining exterior walls between the buildings are permitted to have occupant use openings in accordance with Section 706.8. 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
CBC § 703.7 Medium relevance — show source text
The test assemblies shall be identical in construction, loading and materials, other than the noncombustible protection. The two test assemblies shall be tested to the same criteria of structural failure with the following conditions:
- Test Assembly 1 shall be without protection.
- Test Assembly 2 shall include the representative noncombustible protection. The protection shall be fully defined in terms of configuration details, attachment details, joint sealing details, accessories and all other relevant details.
The noncombustible protection time contribution shall be determined by subtracting the fire-resistance time, in minutes, of Test Assembly 1 from the fire-resistance time, in minutes, of Test Assembly 2.
703.7 Sealing of adjacent mass timber elements. In buildings of Types IV-A, IV-B and IV-C construction, sealant or adhesive shall be provided to resist the passage of air in the following locations:
- At abutting edges and intersections of mass timber building elements required to be fire-resistance rated.
- At abutting intersections of mass timber building elements and building elements of other materials where both are required to be fire-resistance rated.
Sealants shall meet the requirements of ASTM C920. Adhesives shall meet the requirements of ASTM D3498.
Exception: Sealants or adhesives need not be provided where they are not a required component of a tested fire-resistance-rated assembly.
SECTION 704—FIRE-RESISTANCE RATING OF STRUCTURAL MEMBERS
704.1 Requirements. The fire-resistance ratings of structural members and assemblies shall comply with this section and the requirements for the type of construction as specified in Table 601.
704.1.1 Supporting construction. The fire-resistance ratings of supporting structural members and assemblies shall be not less than the ratings required for the fire-resistance-rated assemblies supported by the structural members.
Exception: Structural members and assemblies that support fire barriers, fire partitions, smoke barriers and horizontal assemblies as provided in Sections 707.5, 708.4, 709.4 and 711.2, respectively.
704.2 Protection of the primary structural frame. Members of the primary structural frame that are required to have protection to achieve a fire-resistance rating shall be provided individual encasement protection by protecting them on all sides for the full length, including connections to other structural members, with materials having the required fire-resistance rating. Where a column extends through a ceiling, the encasement protection shall be continuous from the top of the foundation or floor/ceiling assembly below through the ceiling space to the top of the column.
Exceptions:
- Individual encasement protection on all sides shall be permitted on all exposed sides provided that the extent of protection is in accordance with the required fire-resistance rating, as determined in Section 703.
7-4 2025 CALIFORNIA BUILDING CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
FIRE AND SMOKE PROTECTION FEATURES
Primary structural members other than columns that do not support more than two floors or one floor and roof, or a load-bearing wall or a nonload-bearing wall more than two stories high, are permitted to be protected by the membrane of a fire-resistance-rated wall or horizontal assembly where the membrane provides the required fire-resistance rating.
Columns that meet the limitations of Section 704.3.1.
CBC § 1616.2.2.1 Medium relevance — show source text
Demolition 3303 Design Flood 1612 Design Strength Column splice 1616.2.2.1 Conformance to standards 1706.1
New materials 1706.2 Designated Seismic System 1704.3.2, 1704.4, 1704.5 Seismic certification 1705.14.3
Special inspection 1705.13.4 Detached Single-family Dwelling 202 Detectable Warning 202 Diaphragms 202 Analysis 1604.4 Ceilings 2508.6
Penetrations 714
Permit application 105.1 Relocation 107.2.8
Retention 107.5
Review 107.3
Roof assemblies 1503
Roof live load 1603.1.2
Roof rain load data 1603.1.9
Roof snow load 1603.1.3
Seismic 1603.1.5, 1705.14.2, 1705.14.3 Site plan 107.2.6 Special loads 1603.1.8 Temporary structures 3103.2 Wind data 1603.1.4 Construction Types 202, Chapter 6 Aircraft-related occupancies 412.2.1, Table 412.3.6, 412.5.2 Classification 602 Combustible material in Type I and Type II construction 603, 805 Covered and open mall buildings 402.4.1 Fire district D102.2.3
Fire resistance Table 601, Table 705.5 High-rise 403.2 Type I Table 601, 602.2, 603 Type II Table 601, 602.2, 603 Type III Table 601, 602.3 Type IV Table 601, 602.4 Type V Table 601, 602.5 Underground buildings 405.2 Continuity Head-Of-Wall System 202 Continuous Insulation (ci) 202 Contractor’s Responsibilities 901.5, 1704.4 Control Area 414.2, 707.3.8 Construction 414.2.1
Fire-resistance rating 414.2.4 Maximum allowed quantities 414.2.2 Number 414.2.3 Conventional Light-frame Construction 2302.1, 2308 Additional seismic requirements 2308 Braced wall lines 2308.10 Design of elements 2308.8 Floor joists 2308.8.2 Foundation plates or sills 2308.7 Girders 2308.8.1 Roof and ceiling framing 2308.11 Wall framing 2308.9 Conveying System S3004 Cornices
Definition 202 Draftstopping 718.2.6 Live load Table 1607.1
Masonry 2104.1.2 Projection 705.2, 705.2.3.1 Public right-of-way encroachments 3202.3.2, 3202.3.3 Correctional Treatment Centers
[OSHPD 4] 1227 Application 1227.2 Ceiling heights 1227.8 Corridors 1227.5
CBC § 602.1.1 Medium relevance — show source text
3.2. The distance between solar photovoltaic array structures is a minimum of 10 feet clear. 3.3. The driveway aisle separating solar photovoltaic array structures has a minimum width of 25 feet clear. 3.4. Solar photovoltaic array structure is used only for parking purposes with no storage. 3.5. Completely open on all sides (other than necessary structural supports) with no interior partitions.
602.1.1 Minimum requirements. A building or portion thereof shall not be required to conform to the details of a type of construction higher than that type which meets the minimum requirements based on occupancy even though certain features of such a building actually conform to a higher type of construction.
602.2 Types I and II. Types I and II construction are those types of construction in which the building elements specified in Table 601 are of noncombustible materials, except as permitted in Section 603 and elsewhere in this code.
602.3 Type III. Type III construction is that type of construction in which the exterior walls are of noncombustible materials and the interior building elements are of any material permitted by this code. Fire-retardant-treated wood framing and sheathing complying with Section 2303.2 shall be permitted within exterior wall assemblies of a 2-hour rating or less.
602.4 Type IV. Type IV construction is that type of construction in which the building elements are mass timber or noncombustible materials and have fire-resistance ratings in accordance with Table 601. Mass timber elements shall meet the fire-resistance-rating requirements of this section based on either the fire-resistance rating of the noncombustible protection, the mass timber, or a combination of both and shall be determined in accordance with Section 703.2. The minimum dimensions and permitted materials for building elements shall comply with the provisions of this section and Section 2304.11. Mass timber elements of Types IV-A, IV-B and IV-C construction shall be protected with noncombustible protection applied directly to the mass timber in accordance with Sections 602.4.1 through 602.4.3. The time assigned to the noncombustible protection shall be determined in accordance with Section 703.6 and comply with Section 722.7.
Cross-laminated timber shall be labeled as conforming to ANSI/APA PRG 320 as referenced in Section 2303.1.4.
Exterior load-bearing walls and nonload-bearing walls shall be mass timber construction, or shall be of noncombustible construction.
Exception: Exterior load-bearing walls and nonload-bearing walls of Type IV-HT Construction in accordance with Section 602.4.4.
The interior building elements, including nonload-bearing walls and partitions, shall be of mass timber construction or of noncombustible construction.
Exception: Interior building elements and nonload-bearing walls and partitions of Type IV-HT construction in accordance with Section 602.4.4.
Combustible concealed spaces are not permitted except as otherwise indicated in Sections 602.4.1 through 602.4.4. Combustible stud spaces within light frame walls of Type IV-HT construction shall not be considered concealed spaces, but shall comply with Section 718.
Frequently asked questions
How does a building’s type of construction affect allowable height and area?
Type of construction is a primary input to the height‑and‑area tables in Chapter 5: buildings with higher fire‑resistance ratings (as required by their construction type) are permitted greater heights and floor areas; see the chapter cross‑references and the general limits in §503.1 and related tables.
Where are the required fire‑resistance ratings for building elements listed?
Required ratings are shown in Table 601 (fire‑resistance of building elements by construction type) and exterior‑wall requirements are coordinated with Table 705.5; when Table 601 requires a rating, the assembly must comply with §703.2 test/listing requirements.
What differentiates Types I through V?
In short: Types I and II are primarily noncombustible (see §602.2), Type III has noncombustible exterior walls with interior elements of any permitted material (§602.3), Type IV covers mass‑timber (with specific §602.4 rules), and Type V is combustible construction with the least required fire resistance. Consult §602.2–§602.5 and §603 for exceptions and permitted combustible elements in noncombustible types.
More in California Building Code
- Accessibility
- Administration & Permits
- Concrete
- Elevators & Conveying Systems
- Energy Efficiency
- Existing Buildings
- Exterior Walls
- Fire-Resistance & Fire Safety
- Foundations & Soils
- Hazardous Materials & Occupancies
- Interior Finishes
- Masonry
- Means of Egress
- Occupancy Classification & Use
- Roofing & Roof Assemblies
- Special Inspections & Tests
- Steel
- Structural Design
- Types of Construction
- Wood
Ask about the CBC
Get cited, plain-English answers on the California Building Code for your project — any code section, any scenario.
Start Free Trial