CBC · California Building Code
What limits apply to set‑out (dropped) ceilings and furred‑out finishes?
If a wall or ceiling that must be noncombustible or fire‑rated is furred or a ceiling is dropped more than 1 3/4 inches, the finish and supporting components must meet stricter fire requirements (typically Class A finishes and noncombustible hangers) unless the cavity is sprinkler‑protected, noncombustible, or otherwise treated as allowed by the code.
Last reviewed: July 5, 2026
What the code requires — plain English with the controlling §
When interior finish is applied over elements that are required to be fire‑resistance‑rated or noncombustible, the CBC limits how far you can fur out or drop a ceiling and what materials must be used. Furring strips are limited to 1 3/4 inches (44 mm) and any greater set‑out/dropped space triggers stricter finish requirements (Class A finishes, noncombustible hangers, or the exceptions listed) — see § 803.15, § 803.15.1, § 803.15.2 and § 803.15.4.
Requirements in detail
1) Direct attachment and allowable furring
Interior finish applied to fire‑resistance‑rated or noncombustible elements must be applied either directly to the element or to furring strips not exceeding 1 3/4 inches (44 mm). Reference: § 803.15.1.
If furring is used, the concealed intervening spaces must comply with one of three options:
- Be filled with inorganic or noncombustible material;
- Be filled with a material that meets Class A finish performance (per § 803.1.1 or § 803.1.2); or
- Be fireblocked at intervals not greater than 8 feet (2438 mm) in every direction (see § 718). Reference: § 803.15.1.1.
2) Set‑out (dropped) construction threshold and finish class
If walls are set out or ceilings are dropped a distance greater than the furring limit in § 803.15.1 (i.e., > 1 3/4 in / 44 mm), the finish used in that set‑out space must be Class A (tested to § 803.1.1 NFPA 286 or § 803.1.2 ASTM E84/UL 723), unless one of the exceptions applies. Reference: § 803.15.2 and § 803.1.
The hangers and assembly members for dropped ceilings located below a horizontal fire‑resistance‑rated floor or roof must be of noncombustible materials. Exception: in Types III and V construction, fire‑retardant‑treated wood is permitted for hangers/assembly members. Reference: § 803.15.2.1.
3) Thin finishes and prohibition on suspension
An interior finish that is not more than 1/4 inch (6.4 mm) thick must be applied directly onto the wall/ceiling/structural element (no furring) and must not be suspended away from the element. Reference: § 803.15.4.
Exceptions to that prohibition allow:
- Noncombustible finish materials to be furred/suspended;
- Class A materials that were tested in a furred‑out configuration may be used with furring strips; and
- Class A materials tested in a suspended configuration may be used suspended. Reference: § 803.15.4 Exceptions.
Quick decision table (decision‑relevant dimensions / values)
| Issue | Critical numeric limit / requirement | Code Reference |
|---|---|---|
| Maximum furring depth without triggering Class A rule | 1 3/4 in (44 mm) | § 803.15.1 |
| Fireblocking interval for concealed furring spaces | ≤ 8 ft (2438 mm) in every direction | § 803.15.1.1(3) |
| Required finish class when set‑out > furring limit | Class A (per § 803.1.1 or § 803.1.2) | § 803.15.2 and § 803.1.1 / § 803.1.2 |
| Hangers / assembly members for dropped ceilings under rated assembly | Noncombustible (FRT wood permitted in Types III & V) | § 803.15.2.1 |
| Max thickness for “no furring / no suspension” rule | 1/4 in (6.4 mm) | § 803.15.4 |
Exceptions & special cases
Automatic sprinkler protection: The requirement for Class A finishes in set‑outs greater than the furring limit does not apply where the interior finish is protected on both sides by an automatic sprinkler system per § 903.3.1.1 or § 903.3.1.2. Reference: § 803.15.2 Exceptions (1).
Noncombustible backing or allowable tested configurations: If the finish is attached to noncombustible backing, or if the finish was tested and qualified in a furred‑out or suspended configuration as Class A, the stricter limits can be avoided. Reference: § 803.15.2 Exceptions (2) and § 803.15.4 Exceptions (2)-(3).
Filled concealed space: If the combustible void created by furring or a dropped ceiling is filled with noncombustible material, the Class A requirement may be avoided. Reference: § 803.15.2 Exception (3).
Hangers in Types III and V: For dropped ceilings below rated assemblies, fire‑retardant‑treated (FRT) wood hangers are permitted in Types III and V construction instead of noncombustible hangers. Reference: § 803.15.2.1 Exception.
Common mistakes
Assuming any thin finish (≤ 1/4 in) can be furred out or suspended — § 803.15.4 prohibits that unless the material is noncombustible or specifically tested in the furred/suspended configuration.
Forgetting that the 1 3/4 in (44 mm) limit is measured from the required fire‑resistance or noncombustible surface — exceeding it changes the classification and attachment requirements. § 803.15.1 and § 803.15.2 are commonly overlooked.
Using combustible hangers or unsupported metal grid components under rated horizontal assemblies — hangers/assembly members must be noncombustible unless the project is Type III or V and uses FRT wood (see § 803.15.2.1).
Failing to address concealed spaces: leaving the cavity unfilled, unprotected and unfireblocked can violate § 803.15.1.1. Designers must choose one of the three compliance options (inorganic fill, Class A fill, or fireblocking).
Worked example — concrete scenario with numbers
Scenario: You have a horizontal 2‑hour fire‑resistance‑rated floor above a corridor. You want to install a dropped gypsum ceiling 2.5 inches (63.5 mm) below the underside of the rated floor and attach 1/2‑inch gypsum board to a metal grid.
Compare the set‑out to the furring limit:
- 2.5 in > 1 3/4 in (44 mm), so this is a "set‑out greater than specified" situation. Consequence: finishes in that cavity must be Class A per § 803.15.2.
Hangers and assembly members:
- The hangers/grid that support the dropped ceiling are below the rated floor; they must be noncombustible (steel grid is acceptable). If project were Type III or V and you proposed FRT wood hangers, that would be allowed per the exception in § 803.15.2.1.
Concealed space:
- If the cavity contains combustible material (pipes, insulation), you must either (a) fill with noncombustible material, (b) use Class A material in the cavity, or (c) fireblock the cavity at intervals ≤ 8 ft in every direction. If none of those are provided, the installation does not comply. See § 803.15.1.1.
Alternate compliance:
- If the corridor and the area above the ceiling are fully protected by an automatic sprinkler system in accordance with § 903.3.1.1/.1.2, the Class A requirement could be waived per the exceptions in § 803.15.2.
Summary of outcome for this example: Use Class A rated finish materials in the dropped ceiling assembly, use noncombustible hangers (or FRT wood only for Types III/V if applicable), and ensure the concealed space is treated per § 803.15.1.1 or is covered by the sprinkler exception.
Related provisions (CBC)
- § 803.15 — Application of interior finish materials to fire‑resistance‑rated or noncombustible building elements.
- § 803.15.1 — Direct attachment and furred construction (including the 1 3/4 in / 44 mm limit).
- § 803.15.1.1 — Furred construction: fill, Class A fill, or fireblocking (≤ 8 ft / 2438 mm).
- § 803.15.2 — Set‑out construction (Class A requirement and exceptions).
- § 803.15.2.1 — Hangers and assembly members for dropped ceilings.
- § 803.15.3 — Heavy timber construction provisions for finishes against wood decking (fireblocking requirement).
- § 803.15.4 — Materials: 1/4 in (6.4 mm) direct application prohibition on suspension / furring and its exceptions.
- § 803.1.1 and § 803.1.2 — Test methods and Class A/B/C definitions used to determine acceptable finishes (NFPA 286; ASTM E84/UL 723).
- § 718 — Fireblocking requirements (referenced for furred concealed spaces).
- § 903.3.1.1 / § 903.3.1.2 — Automatic sprinkler systems referenced in the exceptions to § 803.15.2.
Code references
Grounded in the retrieved California Building Code — click a citation to read the verbatim passage:
CBC § 5.5 High relevance — show source text
[BSC-CG] See California Green Building Standards Code, Chapter 5, Division 5.5 for additional finish material pollutant control requirements.
SECTION 802—GENERAL
802.1 Interior wall and ceiling finish. The provisions of Section 803 shall limit the allowable fire performance and smoke development of interior wall and ceiling finish materials based on occupancy classification.
802.2 Interior floor finish. The provisions of Section 804 shall limit the allowable fire performance of interior floor finish materials based on occupancy classification.
[F] 802.3 Decorative materials and trim. Decorative materials and trim shall be restricted by combustibility, fire performance or flame propagation performance criteria in accordance with Section 806.
802.4 Applicability. For buildings in flood hazard areas as established in Section 1612.3, interior finishes, trim and decorative materials below the elevation required by Section 1612 shall be flood-damage-resistant materials.
802.5 Application. Combustible materials shall be permitted to be used as finish for walls, ceilings, floors and other interior surfaces of buildings.
802.6 Windows. Show windows in the exterior walls of the first story above grade plane shall be permitted to be of wood or of unprotected metal framing.
802.7 Foam plastics. Foam plastics shall not be used as interior finish except as provided in Section 803.4. Foam plastics shall not be used as interior trim except as provided in Section 806.6.1 or 2604.2. This section shall apply both to exposed foam plastics and to foam plastics used in conjunction with a textile or vinyl facing or cover.
SECTION 803—WALL AND CEILING FINISHES
803.1 General. Interior wall and ceiling finish materials shall be classified for fire performance and smoke development in accordance with Section 803.1.1 or 803.1.2, except as shown in Sections 803.1.3 through 803.15. Materials tested in accordance with Section 803.1.1 shall not be required to be tested in accordance with Section 803.1.2.
803.1.1 Interior wall and ceiling finish materials tested in accordance with NFPA 286. Interior wall and ceiling finish materials shall be classified in accordance with NFPA 286 and comply with Section 803.1.1.1. Materials complying with Section 803.1.1.1 shall be considered to also comply with the requirements of Class A.
803.1.1.1 Acceptance criteria for NFPA 286. The interior finish shall comply with the following:
During the 40 kW exposure, flames shall not spread to the ceiling.
The flame shall not spread to the outer extremity of the sample on any wall or ceiling.
Flashover, as defined in NFPA 286, shall not occur.
The peak heat release rate throughout the test shall not exceed 800 kW.
The total smoke released throughout the test shall not exceed 1,000 m [2] .
803.1.2 Interior wall and ceiling finish materials tested in accordance with ASTM E84 or UL 723. Interior wall and ceiling finish materials shall be classified in accordance with ASTM E84 or UL 723. Such interior finish materials shall be grouped in the following classes in accordance with their flame spread and smoke-developed indices.
Class A = Flame spread index 0–25; smoke-developed index 0–450.
Class B = Flame spread index 26–75; smoke developed index 0–450.
Class C = Flame spread index 76–200; smoke-developed index 0–450.
CBC § 4.420 High relevance — show source text
410|≥4.420|NA|AHRI
550/590| |Water
source
electri-
cally
operated
positive
displace-
ment|<75|≤0.7885
FL
≤0.6316
IPLV.IP|≤0.7875
FL
≤0.5145
IPLV.IP|75/655|NA|NA|NA|≥3.550|NA|NA|NA|6.150|6.150| |Water
source
electri-
cally
operated
positive
displace-
ment|≥75
and
<150|≤0.7579
FL
≤0.5895
IPLV.IP|≤0.7140
FL
≤0.4620
IPLV.IP|54/445|≥4.640|≥3.680|≥2.680|NA|≥8.330|≥6.410|≥4.420|NA|NA| |Water
source
electri-
cally
operated
positive
displace-
ment|≥75
and
<150|≤0.7579
FL
≤0.5895
IPLV.IP|≤0.7140
FL
≤0.4620
IPLV.IP|75/655|NA|NA|NA|≥3.550|NA|NA|NA|6.150|6.150| |Water
source
electri-
cally
operated
positive
displace-
ment|≥150
and
<300|≤0.6947
FL
≤0.5684
IPLV.IP|≤0.7140
FL
≤0.4620
IPLV.IP|54/445|≥4.640|≥3.680|≥2.680|NA|≥8.330|≥6.410|≥4.420|NA|NA| |Water
source
electri-
cally
operated
positive
displace-
ment|≥150
and
<300|≤0.6947
FL
≤0.5684
IPLV.IP|≤0.7140
FL
≤0.4620
IPLV.IP|75/655|NA|NA|NA|≥3.550|NA|NA|NA|6.150|6.150| |Water
source
electri-
cally
operated
positive
displace-
ment|≥300
and
<600|≤0.6421
FL
≤0.5474
IPLV.IP|≤0.6563
FL
≤0.4305
IPLV.IP|54/445|≥4.930|≥3.960|≥2.970|NA|≥8.900|≥6.CBC § 803.15 High relevance — show source text
803.15 Application of interior finish materials to fire-resistance-rated or noncombustible building elements. Where interior finish materials are applied on walls, ceilings or structural elements required to have a fire-resistance rating or to be of noncombustible construction, these finish materials shall comply with the provisions of this section.
803.15.1 Direct attachment and furred construction. Where walls, ceilings or structural elements are required by any provision in this code to be of fire-resistance-rated or noncombustible construction, the interior finish material shall be applied directly against such construction or to furring strips not exceeding 1 [3] / 4 inches (44 mm), applied directly against such surfaces.
803.15.1.1 Furred construction. If the interior finish material is applied to furring strips, the intervening spaces between such furring strips shall comply with one of the following:
- Be filled with material that is inorganic or noncombustible.
- Be filled with material that meets the requirements of a Class A material in accordance with Section 803.1.1 or 803.1.2.
- Be fireblocked at not greater than 8 feet (2438 mm) in every direction in accordance with Section 718.
Exception: Compliance with Item 1, 2 or 3 is not required where the materials used to create the concealed space are noncombustible.
2025 CALIFORNIA BUILDING CODE 8-5
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INTERIOR FINISHES
803.15.2 Set-out construction. Where walls and ceilings are required to be of fire-resistance-rated or noncombustible construction and walls are set out or ceilings are dropped distances greater than specified in Section 803.15.1, Class A finish materials, in accordance with Section 803.1.1 or 803.1.2, shall be used.
Exceptions:
Where interior finish materials are protected on both sides by an automatic sprinkler system in accordance with Section 903.3.1.1 or 903.3.1.2.
Where interior finish materials are attached to noncombustible backing or furring strips installed as specified in Section 803.15.1.1.
Where the combustible void is filled with a noncombustible material.
803.15.2.1 Hangers and assembly members. The hangers and assembly members of such dropped ceilings that are below the horizontal fire-resistance-rated floor or roof assemblies shall be of noncombustible materials. The construction of each set-out wall and horizontal fire-resistance-rated floor or roof assembly shall be of fire-resistance-rated construction as required elsewhere in this code.
Exception: In Types III and V construction, fire-retardant-treated wood shall be permitted for use as hangers and assembly members of dropped ceilings.
CBC § 6.1 High relevance — show source text
d
(pcf)|MINIMUM COMPRES-
SIVE STRENGTH PER
SECTION BK106.6.1
(psi)|WALL-TYPE
REINFORCEMENT
PER TABLE
BK105.3|MINIMUM
THICKNESSc, e, f AT
TOP OF WALL
(inches)|MINIMUM
THICKNESSc, e, f AT
BOTTOM OF WALL
(inches)**| |1,200|100|85|E|9|12| |475|≥ 50 pcf: less than
40 inches from top of wall|40b|E or F|8|12| |475|≥ 70 pcf: from 40 inches to 80
inches from top of wall|55b|55b|55b|55b| |475|≥ 90 pcf: more than 80 inches
from top of wall|85|85|85|85| |Nonload bearing|50 to 100|≥ 60 psi
< 60 psib|E or F|9|9| |For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound = 0.45 kg, 1 pound per cubic foot = 16.02 kg/m3.
a.
Density is to be measured at equilibrium moisture content. Average wall density shall be within ±5 pcf of the tabulated value.
b.
Requires an approved engineered design per Section BK106.6.
c.
Cob thickness only. The interior and exterior cob faces shall be permitted to be unfinished or receive any plaster finish allowed by this appendix.
d.
Cob walls with more than one density shall be built with heavier densities below lighter densities.
e.
Minimum cob wall thickness shall be whichever is greater in Tables BK105.3, BK106.11(1) and BK108.1.
f.
Wall thicknesses less than 10 inches require an engineered design.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound = 0.45 kg, 1 pound per cubic foot = 16.02 kg/m3.
a.
Density is to be measured at equilibrium moisture content. Average wall density shall be within ±5 pcf of the tabulated value.
b.
Requires an approved engineered design per Section BK106.6.
c.
Cob thickness only. The interior and exterior cob faces shall be permitted to be unfinished or receive any plaster finish allowed by this appendix.
d.
Cob walls with more than one density shall be built with heavier densities below lighter densities.
e.
Minimum cob wall thickness shall be whichever is greater in Tables BK105.3, BK106.11(1) and BK108.1.
f.
Wall thicknesses less than 10 inches require an engineered design.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound = 0.45 kg, 1 pound per cubic foot = 16.02 kg/m3.
a.
Density is to be measured at equilibrium moisture content.CBC § 17.4 High relevance — show source text
8|17.4|1.5|2.5|3.4|5.1|0.6|1.0|1.3|1.9| |10|7.7|13.1|17.8|26.3|2.3|3.8|5.2|7.7|0.8|1.4|2.0|2.9| |12|10.8|18.4|24.9|NP|3.2|5.4|7.3|10.7|1.2|2.0|2.7|4.0| |14|14.4|24.5|NP|NP|4.2|7.1|9.6|14.3|1.6|2.7|3.6|5.4| |16|18.4|NP|NP|NP|5.4|9.1|12.4|18.3|2.0|3.4|4.7|6.9| |18|22.9|NP|NP|NP|6.7|11.4|15.4|22.7|2.5|4.3|5.8|8.6| |20|27.8|NP|NP|NP|8.1|13.8|18.7|27.6|3.1|5.2|7.0|10.4| |22|NP|NP|NP|NP|9.7|16.5|22.3|NP|3.7|6.2|8.4|12.4| |24|NP|NP|NP|NP|11.4|19.3|26.2|NP|4.3|7.3|9.9|14.6| |26|NP|NP|NP|NP|13.2|22.4|NP|NP|5.0|8.5|11.4|16.9| |28|NP|NP|NP|NP|15.1|25.7|NP|NP|5.7|9.7|13.1|19.4| |30|NP|NP|NP|NP|17.2|NP|NP|NP|6.5|11.0|14.9|22.0| |32|NP|NP|NP|NP|19.4|NP|NP|NP|7.3|12.4|16.8|24.8| |34|NP|NP|NP|NP|21.7|NP|NP|NP|8.2|13.9|18.8|NP| |36|NP|NP|NP|NP|24.1|NP|NP|NP|9.1|15.4|20.9|NP| |For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 0.063 L/s, 1 pound per square inch = 6.895 kPa.
NP = Not Permitted. Pressure loss exceeds reasonable limits.
a. Values are applicable for underground piping materials listed in_ the California Plumbing Code_ and are based on an SDR of 11 and a Hazen Williams C Factor of 150.
b. Values include the following length allowances for fittings: 25-percent length increase for actual lengths up to 100 feet and 15-percent length increase for actual lengths over
100 feet.
c. Flow rate from Section P2904.4.2.CBC § 803.13 High relevance — show source text
1||X||||||||||||||||||||||| |Table 803.13|||X|||||||||||||||||||||| |804.1|||X|||||||||||||||||||||| |804.4|||X|||||||||||||||||||||| |804.4.1|||X|||||||||||||||||||||| |804.4.2|||X|||||||||||||||||||||| |804.4.3|||X|||||||||||||||||||||| |806.4|||X|||||||||||||||||||||| |806.6|||X||||||||||||||||||||||
The state agency does not adopt sections identified by 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 8-1
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8-2 2025 CALIFORNIA BUILDING CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
8 INTERIOR FINISHES
User notes:
About this chapter: Chapter 8 contains the performance requirements for controlling fire growth and smoke propagation within buildings by restricting interior finish and decorative materials. The provisions of this chapter require materials used as interior finishes and decorations to meet certain flame spread index or flame propagation criteria and smoke development criteria based on the relative fire hazard associated with the occupancy. The performance of the material is evaluated based on test standards.
SECTION 801—SCOPE
801.1 Scope. The provisions of this chapter shall govern the use of materials used as interior finishes, trim and decorative materials.
[BSC-CG] See California Green Building Standards Code, Chapter 5, Division 5.5 for additional finish material pollutant control requirements.
SECTION 802—GENERAL
802.1 Interior wall and ceiling finish. The provisions of Section 803 shall limit the allowable fire performance and smoke development of interior wall and ceiling finish materials based on occupancy classification.
802.2 Interior floor finish. The provisions of Section 804 shall limit the allowable fire performance of interior floor finish materials based on occupancy classification.
[F] 802.3 Decorative materials and trim. Decorative materials and trim shall be restricted by combustibility, fire performance or flame propagation performance criteria in accordance with Section 806.
802.4 Applicability. For buildings in flood hazard areas as established in Section 1612.3, interior finishes, trim and decorative materials below the elevation required by Section 1612 shall be flood-damage-resistant materials.
802.5 Application. Combustible materials shall be permitted to be used as finish for walls, ceilings, floors and other interior surfaces of buildings.
802.6 Windows. Show windows in the exterior walls of the first story above grade plane shall be permitted to be of wood or of unprotected metal framing.
802.7 Foam plastics. Foam plastics shall not be used as interior finish except as provided in Section 803.4. Foam plastics shall not be used as interior trim except as provided in Section 806.6.1 or 2604.2. This section shall apply both to exposed foam plastics and to foam plastics used in conjunction with a textile or vinyl facing or cover.
SECTION 803—WALL AND CEILING FINISHES
CBC § 8-5 High relevance — show source text
Exception: Compliance with Item 1, 2 or 3 is not required where the materials used to create the concealed space are noncombustible.
2025 CALIFORNIA BUILDING CODE 8-5
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
INTERIOR FINISHES
803.15.2 Set-out construction. Where walls and ceilings are required to be of fire-resistance-rated or noncombustible construction and walls are set out or ceilings are dropped distances greater than specified in Section 803.15.1, Class A finish materials, in accordance with Section 803.1.1 or 803.1.2, shall be used.
Exceptions:
Where interior finish materials are protected on both sides by an automatic sprinkler system in accordance with Section 903.3.1.1 or 903.3.1.2.
Where interior finish materials are attached to noncombustible backing or furring strips installed as specified in Section 803.15.1.1.
Where the combustible void is filled with a noncombustible material.
803.15.2.1 Hangers and assembly members. The hangers and assembly members of such dropped ceilings that are below the horizontal fire-resistance-rated floor or roof assemblies shall be of noncombustible materials. The construction of each set-out wall and horizontal fire-resistance-rated floor or roof assembly shall be of fire-resistance-rated construction as required elsewhere in this code.
Exception: In Types III and V construction, fire-retardant-treated wood shall be permitted for use as hangers and assembly members of dropped ceilings.
803.15.3 Heavy timber construction. Wall and ceiling finishes of all classes as permitted in this chapter that are installed directly against the wood decking or planking of heavy timber construction in Section 602.4.4.2 or 2304.11 or to wood furring strips applied directly to the wood decking or planking shall be fireblocked as specified in Section 803.15.1.1. 803.15.4 Materials. An interior wall or ceiling finish material that is not more than [1] / 4 inch (6.4 mm) thick shall be applied directly onto the wall, ceiling or structural element without the use of furring strips and shall not be suspended away from the building element to which that finish material it is applied.
Exceptions:
Noncombustible interior finish materials.
Materials that meet the requirements of Class A materials in accordance with Section 803.1.1 or 803.1.2 where the qualifying tests were made with the material furred out from the noncombustible backing shall be permitted to be used with furring strips.
Materials that meet the requirements of Class A materials in accordance with Section 803.1.1 or 803.1.2 where the qualifying tests were made with the material suspended away from the noncombustible backing shall be permitted to be used suspended away from the building element.
SECTION 804—INTERIOR FLOOR FINISH
804.1 General. Interior floor finish and floor covering materials shall comply with Sections 804.2 through 804.4.2.
Exception: In areas except Groups I-2 with detention and I-3, floor finishes and coverings of a traditional type, such as wood, vinyl, linoleum or terrazzo, and resilient floor covering materials that are not composed of fibers.
CBC § 0.447 High relevance — show source text
b—continued Col2 Col3 Col4 Col5 Col6 Col7 Col8 ** WALL SUPPORTING** ** ROOF SLOPE** ** ULTIMATE WIND SPEED AND EXPOSURE**
(mph)** ULTIMATE WIND SPEED AND EXPOSURE**
(mph)** ULTIMATE WIND SPEED AND EXPOSURE**
(mph)** ULTIMATE WIND SPEED AND EXPOSURE**
(mph)** ULTIMATE WIND SPEED AND EXPOSURE**
(mph)** ULTIMATE WIND SPEED AND EXPOSURE**
(mph)** WALL SUPPORTING** ** ROOF SLOPE** ** 115 B** ** 120 B** ** 130 B** ** < 140 B** ** < 130 C** ** < 140 C** ** WALL SUPPORTING** ** ROOF SLOPE** ** 115 B** ** 120 B** ** 115 C** ** 120 C** ** 120 C** ** 120 C** Two stories, roof and ceiling
(first floor of a three-story building)3:12 43 53 57 64 89 113 Two stories, roof and ceiling
(first floor of a three-story building)6:12 41 51 51 67 95 114 Two stories, roof and ceiling
(first floor of a three-story building)9:12 53 63 63 89 104 126 Two stories, roof and ceiling
(first floor of a three-story building)12:12 54 67 74 100 142 157 For SI: 1 mph = 0.447 m/s.
a. Linear interpolation is permitted.
b. For hip-roofed homes the minimum percentage of full-height sheathing, based on wind, is permitted to be multiplied by a factor of 0.95 for roof slopes not exceeding 7:12
and a factor of 0.9 for roof slopes greater than 7:12.For SI: 1 mph = 0.447 m/s.
a. Linear interpolation is permitted.
b. For hip-roofed homes the minimum percentage of full-height sheathing, based on wind, is permitted to be multiplied by a factor of 0.95 for roof slopes not exceeding 7:12
and a factor of 0.9 for roof slopes greater than 7:12.For SI: 1 mph = 0.447 m/s.
a. Linear interpolation is permitted.
b. For hip-roofed homes the minimum percentage of full-height sheathing, based on wind, is permitted to be multiplied by a factor of 0.95 for roof slopes not exceeding 7:12
and a factor of 0.9 for roof slopes greater than 7:12.For SI: 1 mph = 0.447 m/s.
a. Linear interpolation is permitted.
b. For hip-roofed homes the minimum percentage of full-height sheathing, based on wind, is permitted to be multiplied by a factor of 0.95 for roof slopes not exceeding 7:12
and a factor of 0.9 for roof slopes greater than 7:12.For SI: 1 mph = 0.447 m/s.
a. Linear interpolation is permitted.
b.CBC § 2.25 High relevance — show source text
000 Btu/h and
< 135,000 Btu/h
(cooling capacity)|17°F db/15°F wb
outdoor air|2.25 COP|2.25 COP| |Air cooled
(heating mode)
Split system and single package|≥ 135,000 Btu/h and
< 240,000 Btu/h
(cooling capacity)|47°F db/43°F wb
outdoor air|Federal Minimum COP|Federal Minimum COP| |Air cooled
(heating mode)
Split system and single package|≥ 240,000 Btu/h and
< 760,000 Btu/h|≥ 240,000 Btu/h and
< 760,000 Btu/h|Federal Minimum COP|Federal Minimum COP| |Air cooled
(heating mode)
Split system and single package|≥ 135,000 Btu/h
(cooling capacity)|17°F db/15°F wb
outdoor air|2.05 COP|2.05 COP| |Water source
(heating mode)|< 135,000 Btu/h
(cooling capacity)|68ºF entering water|Federal Minimum COP|ISO-13256-1| |Water source
(heating mode)|≥ 135,000 Btu/h and
< 240,000 Btu/h|68ºF entering water|Federal Minimum COP|ISO-13256-1| |Groundwater source
(heating mode)|< 135,000 Btu/h
(cooling capacity)|50ºF entering water|3.7 COP|ISO-13256-1| |Ground source
(heating mode)|< 135,000 Btu/h
(cooling capacity)|32ºF entering water|3.2 COP|ISO-13256-1| |Water source water-to-water
(heating mode)|< 135,000 Btu/h
(cooling capacity)|68ºF entering water|3.7 COP|ISO-13256-2| |Groundwater source water-to-
water
(heating mode)|< 135,000 Btu/h
(cooling capacity)|50ºF entering water|3.1 COP|ISO-13256-2| |Ground source brine-to-water
(heating mode)|< 135,000 Btu/h
(cooling capacity)|32ºF entering water|2.5 COP|ISO-13256-2| |a. Deduct 0.2 from the required EERs and IEERs for units with a heating section other than electric resistance heat.
b. Applicable test procedure and reference year are provided under the definitions.|a. Deduct 0.2 from the required EERs and IEERs for units with a heating section other than electric resistance heat.
b. Applicable test procedure and reference year are provided under the definitions.|a. Deduct 0.2 from the required EERs and IEERs for units with a heating section other than electric resistance heat.
b. Applicable test procedure and reference year are provided under the definitions.|a. Deduct 0.2 from the required EERs and IEERs for units with a heating section other than electric resistance heat.
b. Applicable test procedure and reference year are provided under the definitions.|a. Deduct 0.2 from the required EERs and IEERs for units with a heating section other than electric resistance heat.
b. Applicable test procedure and reference year are provided under the definitions.|CBC § 403.7 High relevance — show source text
1
Table 403.7 Notes 11 & 12BSC 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
Adopt Entire Chapter
Adopt Entire Chapter as
amended (amended sections
listed below)
Adopt only those sections
that are listed below
Chapter/Section
401.1
401.3
401.3.1
402.1
402.1.2
402.2
402.3
403.0
403.7.2.1 – 403.7.2.4
405.3
406.0
407.0
408.0
409.0
410.0
411.0
412.0
413.0
414.0
415.0
416.0 – 416.2
416.3
416.4
417.0
418.0
419.0
Table 4-A
Table 4-B
Table 4-C
Table 402.1
Table 403.7_Notes 11 & 12_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 Adopting Agency
Adopt Entire Chapter
Adopt Entire Chapter as
amended (amended sections
listed below)
Adopt only those sections
that are listed below
Chapter/Section
401.1
401.3
401.3.1
402.1
402.1.2
402.2
402.3
403.0
403.7.2.1 – 403.7.2.4
405.3
406.0
407.0
408.0
409.0
410.0
411.0
412.0
413.0
414.0
415.0
416.0 – 416.2
416.3
416.4
417.0
418.0
419.0
Table 4-A
Table 4-B
Table 4-C
Table 402.1
Table 403.CBC § 8-8 Medium relevance — show source text
CHAPTER 8-8 ARCHAIC MATERIALS AND METHODS OF
CONSTRUCTION . . . . . . . . . . . . . . . . . . . . . . . 15
Section
8-801 Purpose, Intent and Scope . . . . . . . . . . . . . . . . . . . . . . 15 8-802 General Engineering Approaches. . . . . . . . . . . . . . . . . 15 8-803 Nonstructural Archaic Materials. . . . . . . . . . . . . . . . . . 15
8-804 Allowable Conditions for Specific Materials . . . . . . . 15 8-805 Masonry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 8-806 Adobe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
8-807 Wood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
8-808 Concrete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
8-809 Steel and Iron . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
8-810 Hollow Clay Tile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
8-811 Veneers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
8-812 Glass and Glazing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
CHAPTER 8-9 MECHANICAL, PLUMBING AND ELECTRICAL REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . 19
Section
8-901 Purpose, Intent and Scope . . . . . . . . . . . . . . . . . . . . . . 19 8-902 Mechanical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
8-903 Plumbing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 8-904 Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
CHAPTER 8-10 QUALIFIED HISTORICAL DISTRICTS,
SITES AND OPEN SPACES . . . . . . . . . . . . . . . 23
Section
CBC § 31F-2 Medium relevance — show source text
holes_
Severe mechanical damage|Major spalling and cracking
Severe reinforcement corrosion
Broken piles|Major loss of section
Broken piles and bracings
Severe abrasion or marine
borer attack|Permanent deformation
Broken piles
Major cracking or
mechanical damage| |II|To detect surface defects
normally obscured by
marine growth|Moderate mechanical
damage
Corrosion pitting and loss of
section|Surface cracking and spalling
Rust staining
Exposed reinforcing steel and/
or prestressing strands|External pile damage due
to marine borers
Splintered piles
Loss of bolts and fasteners
Rot or insect infestation|Cracking
Delamination
Material degradation| |III|To detect hidden or
interior damage,
evaluate loss of cross-
sectional area or
evaluate material
homogeneity|Thickness of material
Electrical potentials for
cathodic protection|Location of reinforcing steel
Beginning of corrosion of
reinforcing steel
Internal voids
Change in material strength|Internal damage due to
marine borers (internal
voids)
Decrease in material
strength|N/A|TABLE 31F-2-3—SCOPE OF UNDERWATER INSPECTION [2.2] Col2 Col3 Col4 Col5 Col6 Col7 Col8 Col9 Col10 LEVEL SAMPLE SIZE AND METHODOLOGY1 SAMPLE SIZE AND METHODOLOGY1 SAMPLE SIZE AND METHODOLOGY1 SAMPLE SIZE AND METHODOLOGY1 SAMPLE SIZE AND METHODOLOGY1 SAMPLE SIZE AND METHODOLOGY1 SAMPLE SIZE AND METHODOLOGY1 SAMPLE SIZE AND METHODOLOGY1 LEVEL Steel Steel Concrete Concrete Timber Timber Composite Slope
Protection,
Channel
**_Bottom
Frequently asked questions
Can I fur out a wall 2 inches and use ordinary gypsum board?
No — 2 inches (50.8 mm) exceeds the 1 3/4 in (44 mm) furring limit in § 803.15.1, so the cavity becomes a set‑out that generally requires Class A finishes unless an exception (sprinklers, noncombustible backing, noncombustible fill) applies.
If my thin veneer is 1/8 inch thick, can I suspend it away from the wall?
Not unless it is noncombustible or is a Class A material that was tested and qualified in a suspended or furred‑out configuration; otherwise § 803.15.4 prohibits suspending finishes ≤ 1/4 in (6.4 mm).
Do suspended acoustical ceilings have different rules?
Suspended acoustical ceilings used as part of fire‑resistance assemblies must be installed as tested and comply with Chapter 7 and ASTM standards in § 808. Acoustical materials must still meet the interior finish requirements of § 803.
Are there circumstances where hanger members can be wood?
Yes — for dropped ceilings below horizontal rated assemblies, hangers and assembly members must be noncombustible, except in Type III and Type V construction where fire‑retardant‑treated (FRT) wood hangers are permitted per § 803.15.2.1.
If I have sprinklers in the ceiling cavity, can I avoid Class A finishes?
If the interior finishes are protected on both sides by an automatic sprinkler system installed per § 903.3.1.1 or § 903.3.1.2, the Class A requirement in § 803.15.2 may be excepted. Confirm sprinkler design and coverage with the authority having jurisdiction.
More in California Building Code
- Administration & Permits
- Energy Efficiency
- Existing Buildings
- Occupancy Classification & Use
- Hazardous Materials & Occupancies
- Types of Construction
- Fire-Resistance & Fire Safety
- Interior Finishes
- Means of Egress
- Accessibility
- Exterior Walls
- Roofing & Roof Assemblies
- Structural Design
- Special Inspections & Tests
- Foundations & Soils
- Concrete
- Masonry
- Steel
- Wood
- Elevators & Conveying Systems
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