CRC · California Residential Code

Which accessibility standard (ICC A117.1) is referenced for residential elements?

Q: What edition of A117.1 does the CRC reference?

The CRC references ICC A117.1 — 2017 for the CRC sections listed in the referenced‑standards table.

Q: For acoustics, what is the numeric trigger that makes A117.1 § 808 apply?

If the classroom (addition) volume is 20,000 cubic feet or less , § 502.6 requires compliance with the reverberation‑time limits in ICC A117.1 § 808 .

CRC adopts ICC A117.1‑2017 for only a few residential sections: **§ 502.6, § 503.18, § 1011.4, § 1101.6**. Notably **§ 502.6** requires classroom additions ≤ **20,000 ft³** to meet the **reverberation‑time** limits in **A117.1 § 808**; the CRC referenced‑standards table confirms the A117.1‑2017 linkage for the other listed sections. file

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Last reviewed: July 6, 2026

What the code requires — plain English

The California Residential Code (CRC) adopts ICC A117.1 — 2017 (Accessible and Usable Buildings and Facilities) as the referenced accessibility standard for a small set of residential-related elements. The CRC explicitly ties ICC A117.1‑2017 to § 502.6, § 503.18, § 1011.4, and § 1101.6 of the CRC.

Not all accessibility topics in the CRC point to A117.1; where A117.1 is referenced the specific CRC section controls the applicability and tells you which A117.1 provision to use. For example, § 502.6 requires enhanced classroom acoustics to comply with the reverberation‑time criteria in Section 808 of ICC A117.1.

The single most important rule: when a CRC section lists ICC A117.1 as its referenced standard, follow the CRC section’s instruction and the identified A117.1 section (the CRC section is the controlling direction).

Requirements in detail

Which CRC sections point to ICC A117.1 (summary)

§ 502.6 — Enhanced classroom acoustics: additions with classroom volume ≤ 20,000 cubic feet must meet the reverberation time in Section 808 of ICC A117.1.
§ 503.18, § 1011.4, § 1101.6 — The CRC lists these sections as referencing ICC A117.1‑2017 in its referenced‑standards table; the CRC identifies A117.1‑2017 as the standard for those specific items. The published CRC referenced‑standards listing ties A117.1‑2017 to these four CRC sections.

Note: the CRC's referenced‑standards table is the authoritative pointer — the CRC section calling out A117.1 controls which A117.1 provision applies.

Decision‑relevant dimensions and values

Decision item	Value / threshold	What to check	Code Reference
Classroom volume threshold	20,000 cubic feet	If an added classroom has volume ≤ this, enhanced acoustics apply	§ 502.6
Required A117.1 clause for acoustics	Section 808 (reverberation time)	Use A117.1‑2017 Section 808 performance limits for reverberation time	§ 502.6 → ICC A117.1‑2017 Section 808
CRC sections that reference A117.1‑2017	§ 502.6, § 503.18, § 1011.4, § 1101.6	Use the CRC section text to identify the exact A117.1 clause required	CRC referenced‑standards list
A117.1 edition referenced	2017	Confirm you are using the 2017 edition where the CRC points to A117.1	CRC referenced‑standards list

How to apply

Locate the CRC section (one of the four above) that applies to your work. The CRC section tells you which clause or performance metric of ICC A117.1‑2017 to use.
For acoustics under § 502.6, measure or calculate classroom volume; if ≤ 20,000 ft³ you must meet the reverberation‑time limits in A117.1 § 808.
For the other listed sections (§ 503.18, § 1011.4, § 1101.6), consult the CRC section text to determine the referenced A117.1 sub‑section — the CRC referenced‑standards table confirms the linkage but the CRC section itself is the controlling direction.

Exceptions & special cases

The CRC only adopts A117.1‑2017 for the CRC sections listed — it does not automatically adopt the entire A117.1 standard for all residential provisions. Check each CRC section to see whether it actually points to A117.1 and which sub‑clause.
The CRC’s Part IX (Referenced Standards) shows which external standards are adopted and which CRC sections reference them; adoption is limited to the CRC sections explicitly named. The referenced‑standards chapter governs applicability.
Where text of a CRC section contains a specific A117.1 cross‑reference (for example § 502.6 → Section 808), that is the exact A117.1 provision to use. If a CRC section only lists A117.1 in the referenced‑standards table without further direction, the CRC section text must be read to determine scope and applicability. file

(If you need the verbatim CRC wording for § 503.18, § 1011.4, or § 1101.6 the uploaded CRC materials available to me only show the referenced‑standards mapping; I could not retrieve the full text of those three individual CRC sections from the provided files. The referenced‑standards list still confirms that those sections reference ICC A117.1‑2017. )

Common mistakes

Assuming A117.1 applies everywhere in the CRC. Only the CRC sections that explicitly reference A117.1 adopt it — check the CRC section first.
Using the wrong edition of A117.1. The CRC points to ICC A117.1—2017 (not later editions) for the listed sections — verify edition.
Applying A117.1 details without following the CRC section’s scope or thresholds (for example, applying acoustic rules where the classroom volume exceeds the CRC threshold). For acoustics, confirm the 20,000 ft³ threshold in § 502.6 before applying A117.1 § 808.
Confusing the CRC cross‑references with the CBC (Building Code) accessibility chapters — always use the CRC section you are working under (and its referenced standards) for residential work.

Worked example — concrete numbers

Scenario: You are altering a residential facility and converting an existing loft into a small classroom within an addition. The resulting classroom has internal dimensions producing a volume of 18,500 cubic feet.

Step 1 — Threshold check: 18,500 ft³ is ≤ the 20,000 ft³ threshold listed in § 502.6, so the enhanced classroom acoustics requirement applies. (18,500 ≤ 20,000).

Step 2 — Which A117.1 clause to use: § 502.6 directs you to the reverberation‑time requirements in ICC A117.1 Section 808. Use the A117.1‑2017 Section 808 numeric reverberation limits and testing/measurement approach to show compliance.

Step 3 — Document compliance: include the classroom volume calculation, the reverberation‑time test or modeled prediction that shows meeting A117.1 § 808 limits, and reference § 502.6 and ICC A117.1‑2017 § 808 in your compliance submittal. file

Related provisions (CRC)

§ 502.6 — Enhanced classroom acoustics (references ICC A117.1 § 808).
§ 503.18 — CRC section listed as referencing ICC A117.1‑2017 in the referenced‑standards table. (Full text not retrieved in provided files.)
§ 1011.4 — CRC section listed as referencing ICC A117.1‑2017 in the referenced‑standards table. (Full text not retrieved in provided files.)
§ 1101.6 — CRC section listed as referencing ICC A117.1‑2017 in the referenced‑standards table. (Full text not retrieved in provided files.)
Part IX — Chapter 44 (Referenced Standards) — explains that only those CRC sections specifically adopting an external standard are bound to it; consult this chapter when confirming whether a standard is applicable.

Code references

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

CRC § 101.2 High relevance — show source text
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

REFERENCED STANDARDS

CRC—25: California Residential Code

101.2, 101.4.1, 104.3.1, 109.3.3, 109.3.10, 302.2, 307.1, 308.1, 401.3, 402.1, 405.2.6, 502.2, 502.3, 502.4, 503.2, 503.3, 503.11, 505.2, 505.3, 507.3, 701.3, 702.4, 702.5, 706.2, 708.1, 805.2, 806.4, 809.1, 906.2, 907.1, 1011.2.1, 1103.1, 1103.2, 1103.3, 1104.1, 1201.4, 1302.1.2, 1302.1.3, 1302.1.3, 1303.1.3, 1401.2, 1402.1, 1402.2, 1402.2.1, 1402.3, 1402.4, 1402.5, 1402.6

ICC 300—2023: ICC Standard on Bleachers, Folding and Telescopic Seating and Grandstands

301.1.1, 401.1.1, 1401.1.1

ICC A117.1—2017: Accessible and Usable Buildings and Facilities

502.6, 503.18, 1011.4, 1101.6

ICC/NSSA 500—2020: ICC/NSSA Standard for the Design and Construction of Storm Shelters

303.1.1, 303.2

ICCPC—24: ICC Performance Code®

104.2.3

IFGC—24: International Fuel Gas Code®

IPMC—24: International Property Maintenance Code®

101.4.2, 302.2, 1303.1.2, 1401.2

NFPA National Fire Protection Association, 1 Batterymarch Park, Quincy, MA 02169-7471

NFPA 72— 25 : National Fire Alarm and Signaling Code

Revise Section 10.3.1 as follows:

10.3.1 Equipment constructed and installed in conformity with this Code shall be listed for the purpose for which it is used. Fire alarm systems and components shall be California State Fire Marshal approved and listed in accordance with California Code of Regulations, Title 19, Division 1.

Revise Section 10.3.3 as follows:

10.3.3 All devices and appliances that receive their power from the initiating device circuit or signaling line circuit of a control unit shall be California State Fire Marshal listed for use with the control unit.

Revise Section 12.3.8.1 as follows:

12.3.8.1 The outgoing and return (redundant) circuit conductors shall be permitted in the same cable assembly (i.e., multiconductor cable), enclosure or raceway only under the following conditions:
CRC § 5704.2.8.9 High relevance — show source text
1, 5704.2.8.9, 5705.3.7.5.1, 5706.2, 5706.4.4, 6003.1.3, 6003.2.3.2, 6004.2.2.7, 6005.3.1, 6005.3.2, 6103.2.1.7

CPC—25: California Plumbing Code

201.3, 903.3.5, 904.11.1.3, 912.6, 2311.2.3, 5004.2.2.6

CRC—25: California Residential Code

102.5, 202, 913.1, 1001.1, 1205.1, 1205.2.1

ICC 300—2017: Standard on Bleachers, Folding and Telescopic Seating and Grandstands

1030.1.1, 1030.17

ICC ES AC 331: Acceptance Criteria for Smoke and Heat Vents

910.3.1

ICC 500—2020: ICC/NSSA Standard on the Design and Construction of Storm Shelters

1031.2

ICC A117.1—2017: Accessible and Usable Buildings and Facilities

907.5.2.3.3, 1009.2.2, 1009.8.2, 1009.9, 1009.11, 1010.2.12.1, 1012.1, 1012.6.5, 1012.10, 1013.4, 1023.11

IFGC—24: International Fuel Gas Code®

201.3, 605.1, 605.2.1.3, 605.3, 605.5.2, 605.7, 610.1.1, 1206.9, 2301.1, 2301.6, 2308.1, 2309.3.1.2, 2309.3.1.5, 2504.5, 3001.1, 3003.1, 3004.1, 3004.2, 3108.12.1, 3108.12.2, 3305.1.2, 3309.2.2, 4101.6.1, Table 5003.1.1(1), 5301.1, 5801.1, 5803.1.4, 6103.1, 6103.2.1.7,

6103.3

IIAR International Institute of Ammonia Refrigeration, 1001 N. Fairfax Street, Suite 503, Alexandria, VA 22314

ANSI/IIAR 2—2021: Safe Design of Closed-Circuit Ammonia Refrigeration Systems

608.1.2, 608.9

ANSI/IIAR 6—2019: Standard for Inspection, Testing, and Maintenance of Closed-Circuit Ammonia Refrigeration Systems

608.1.2

ANSI/IIAR 7—2019: Developing Operating Procedures for Closed-Circuit Ammonia Refrigeration Systems

608.1.2

ANSI/IIAR 8—2020: Decommissioning of Closed-Circuit Ammonia Refrigeration Systems

608.1.2
CRC § 2311.3.1 High relevance — show source text
2, 2311.3.1, 2311.4.3, 2311.8.2, 2311.8.8, 2311.8.10, 2404.9, 2404.9.2, 2504.5, 2703.2.2, 2703.10.4, 2703.14, 2803.2, 2803.3, 3001.1, 3003.1, 3004.2, 3108.12.1, 3108.12.2, 3703.5, 3804.1.1.7, 3904.1, 3905.3, Table 5003.1.1(1), 5003.8.4.2, 5003.8.5.2, 5003.8.6.2, 5004.3.1, 5303.7.6, 5303.16.9, 5305.5, 5306.2.2, 5306.2.3, 5307.4.4, 5504.2.1.3, 5504.2.2.3, 5505.4.1.1, 5701.3, 5703.6.1, 5704.2.8.9, 5705.3.7.5.1, 5706.2, 5706.4.4, 6003.1.3, 6003.2.3.2, 6004.2.2.7, 6005.3.1, 6005.3.2, 6103.2.1.7

CPC—25: California Plumbing Code

201.3, 903.3.5, 904.11.1.3, 912.6, 2311.2.3, 5004.2.2.6

CRC—25: California Residential Code

102.5, 202, 913.1, 1001.1, 1205.1, 1205.2.1

ICC 300—2017: Standard on Bleachers, Folding and Telescopic Seating and Grandstands

1030.1.1, 1030.17

ICC ES AC 331: Acceptance Criteria for Smoke and Heat Vents

910.3.1

ICC 500—2020: ICC/NSSA Standard on the Design and Construction of Storm Shelters

1031.2

ICC A117.1—2017: Accessible and Usable Buildings and Facilities

907.5.2.3.3, 1009.2.2, 1009.8.2, 1009.9, 1009.11, 1010.2.12.1, 1012.1, 1012.6.5, 1012.10, 1013.4, 1023.11

IFGC—24: International Fuel Gas Code®
CRC § 14.3 High relevance — show source text
ICC-ES AC 156—24: Acceptance Criteria for Seismic Certification by Shake-Table Testing of Nonstructural Components*

1705A.14.3

ICC-ES AC 178—24: : Acceptance Criteria for Inspection and Verification of Concrete, and Reinforced and Unreinforced Masonry* Strengthening Using Fiber-Reinforced Polymer (FRP) Composite Systems

1911A.3, 1911.3

ICC-ES AC 193—24: Acceptance Criteria for Mechanical Anchors in Concrete Elements*

1617A.1.19, 1901.3.2

ICC-ES AC 232—24: Acceptance Criteria for Anchor Channels in Concrete Elements*

1617A.1.19, 1901.3.2

ICC-ES AC 308—24: Acceptance Criteria for Post-Installed Adhesive Anchors in Concrete Elements*

1617A.1.19, 1901.3.3

ICC-ES AC 331: Acceptance Criteria for Smoke and Heat Vents

910.3.1

ICC-ES AC 358—24: Acceptance Criteria for Helical Foundation Systems and Devices*

1810A.3.1.5.1, 1810.3.1.5.1

ICC-ES AC 446—24: Acceptance Criteria for Headed Cast-in Specialty Inserts in Concrete*

1617A.1.19, 1901.3.2

ICC 1100—2019: Standard for Spray-applied Foam Plastic Insulation

2603.1.1

ICC/MBI 1200—2021: [OSHPD 1, 1R, 2, 4, and 5] Standard for Off-Site Construction: Planning, Design, Fabrication and Assembly

1710, 1710A

ICC/MBI 1205—2021: [OSHPD 1, 1R, 2, 4, and 5] Standard for Off-Site Construction: Inspection and Regulatory Compliance

1710, 1710A

SSTD 11—97: 1997 SBCCI Test Standard for Determining Wind Resistance of Concrete or Clay Roof Tiles

1504.3.1.1, 1504.3.1.2, 1504.3.1.3

* Refers to International Building Code, 2024 as a referenced standard.

ISO International Organization for Standardization, Chemin de Blandonnet 8 CP 401 1214 Vernier, Geneva, Switzerland

ISO 668—2013: Series 1 Freight Containers—Classifications, Dimensions and Ratings

Table 3114.8.5.3

ISO 1496-1—2013: Series 1 Freight Containers—Specification and Testing - Part 1: General Cargo Containers for General Purposes 3114.8, Table 3114.8.5.3

ISO 6346—1995: Freight Containers—Coding, Identification and Marking with Amendment 3—2012

3114.3

ISO 8115—86: Cotton Bales—Dimensions and Density Table 307.1(1), Table 415.11.1.1
CRC § 101.2.2 High relevance — show source text
CFC—25: California Fire Code

101.2.2, 101.4.2, 301.3.1, 302.2, 307.1, 308.1, 802.2.1, 802.2.3, 803.2.3, 803.4.1.1, 803.4.1.2, 803.4.1.3, 803.4.1.4, 803.4.1.5, 803.4.1.6, Table 804.5.1.1(1), 904.1.5, 1011.6.1.1, 1303.1.2, 1305.2.8.1, 1305.2.14, 1305.2.14.1, 1401.2, 1501.1, 1501.5, 1502.1, 1502.1.1, 1502.2, 1502.3, 1504.1, 1507.1, 1507.2

CMC—25: California Mechanical Code

302.2, 702.7, 807.1, 902.1.1, 1008.1, 1305.2.7.1, 1305.2.8, 1305.2.8.1

CPC—25: California Plumbing Code

302.2, 408.1, 702.7, 1009.1, 1009.2, 1009.3, 1009.5, 1302.1.6, 1503.1

16-4 2025 CALIFORNIA EXISTING BUILDING CODE

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REFERENCED STANDARDS

CRC—25: California Residential Code

101.2, 101.4.1, 104.3.1, 109.3.3, 109.3.10, 302.2, 307.1, 308.1, 401.3, 402.1, 405.2.6, 502.2, 502.3, 502.4, 503.2, 503.3, 503.11, 505.2, 505.3, 507.3, 701.3, 702.4, 702.5, 706.2, 708.1, 805.2, 806.4, 809.1, 906.2, 907.1, 1011.2.1, 1103.1, 1103.2, 1103.3, 1104.1, 1201.4, 1302.1.2, 1302.1.3, 1302.1.3, 1303.1.3, 1401.2, 1402.1, 1402.2, 1402.2.1, 1402.3, 1402.4, 1402.5, 1402.6

ICC 300—2023: ICC Standard on Bleachers, Folding and Telescopic Seating and Grandstands

301.1.1, 401.1.1, 1401.1.1

ICC A117.1—2017: Accessible and Usable Buildings and Facilities
CRC § 2603.4 High relevance — show source text
ANSI/FM 4880—2017: American National Standard for Evaluating the Fire Performance of Insulated Building Panel Assemblies and Interior Finish Materials

2603.4, 2603.9

GA Gypsum Association, 962 Wayne Avenue, Suite 620, Silver Spring, MD 20910

GA-216—2021: Application and Finishing of Gypsum Panel Products Table 2508.1, 2509.2

GA-253—2021: Application of Gypsum Sheathing Table 2508.1, 2508.2

GA-600—2021: Fire-resistance and Sound Control Design Manual, 23rd Edition Table 721.1(1), Table 721.1(2), Table 721.1(3)

ICC International Code Council, Inc., 200 Massachusetts Avenue, NW, Suite 250, Washington, DC 20001

ICC 300—2017: ICC Standard on Bleachers, Folding and Telescopic Seating, and Grandstands

1030.1.1, 1030.7, 1607.18

ICC 300—23: [DSA-SS, DSA-SS/CC, OSHPD 1, 1R, 2, 4 and 5] Standards Specification on Bleachers, Folding and Telescopic Seating, and Grandstands

1030.1.1, 1030.7, 1607.18, 1605A.3, 1605A.3.1, 1607A.18

ICC 400—2022: Standard on Design and Construction of Log Structures

2302.1

ICC 600—2020: Standard for Residential Construction in High-Wind Regions

1609.1.1, 1609.1.1.1, 2308.2.4

ICC 900/SRCC 300—2020: Solar Thermal System Standard

3111.2.1

ICC 901/SRCC 100—2020: Solar Thermal Collector Standard

3111.2.1

ICC-ES AC 01—24: Acceptance Criteria for Expansion Anchors in Masonry Elements*

1617A.1.19

35-26 2025 CALIFORNIA BUILDING CODE

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REFERENCED STANDARDS

ICC-ES AC 58—24: Acceptance Criteria for Adhesive Anchors in Masonry Elements*

1617A.1.19

ICC-ES AC 70—24: Acceptance Criteria for Fasteners Power-Driven into Concrete, Steel and Masonry Elements*

1617A.1.20

ICC-ES AC 77: Acceptance Criteria for Smoke Containment Systems Used with Fire-resistance-rated Elevator Hoistway Doors and Frames

3006.3

ICC-ES AC 106—24: Acceptance Criteria for Predrilled Fasteners (Screw Anchors) in Masonry*

1617A.1.19

ICC-ES AC 125—24: Acceptance Criteria for Concrete and Reinforced and Unreinforced Masonry Strengthening* Using Externally Bonded Fiber-Reinforced Polymer (FRP) Composite Systems

1911A.3, 1911.3
CRC § 1609.1.1 High relevance — show source text
1609.1.1, 1609.1.1.1, 2308.2.4

ICC 900/SRCC 300—2020: Solar Thermal System Standard

3111.2.1

ICC 901/SRCC 100—2020: Solar Thermal Collector Standard

3111.2.1

ICC-ES AC 01—24: Acceptance Criteria for Expansion Anchors in Masonry Elements*

1617A.1.19

35-26 2025 CALIFORNIA BUILDING CODE

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REFERENCED STANDARDS

ICC-ES AC 58—24: Acceptance Criteria for Adhesive Anchors in Masonry Elements*

1617A.1.19

ICC-ES AC 70—24: Acceptance Criteria for Fasteners Power-Driven into Concrete, Steel and Masonry Elements*

1617A.1.20

ICC-ES AC 77: Acceptance Criteria for Smoke Containment Systems Used with Fire-resistance-rated Elevator Hoistway Doors and Frames

3006.3

ICC-ES AC 106—24: Acceptance Criteria for Predrilled Fasteners (Screw Anchors) in Masonry*

1617A.1.19

ICC-ES AC 125—24: Acceptance Criteria for Concrete and Reinforced and Unreinforced Masonry Strengthening* Using Externally Bonded Fiber-Reinforced Polymer (FRP) Composite Systems

1911A.3, 1911.3

ICC-ES AC 156—24: Acceptance Criteria for Seismic Certification by Shake-Table Testing of Nonstructural Components*

1705A.14.3

ICC-ES AC 178—24: : Acceptance Criteria for Inspection and Verification of Concrete, and Reinforced and Unreinforced Masonry* Strengthening Using Fiber-Reinforced Polymer (FRP) Composite Systems

1911A.3, 1911.3

ICC-ES AC 193—24: Acceptance Criteria for Mechanical Anchors in Concrete Elements*

1617A.1.19, 1901.3.2

ICC-ES AC 232—24: Acceptance Criteria for Anchor Channels in Concrete Elements*

1617A.1.19, 1901.3.2

ICC-ES AC 308—24: Acceptance Criteria for Post-Installed Adhesive Anchors in Concrete Elements*

1617A.1.19, 1901.3.3

ICC-ES AC 331: Acceptance Criteria for Smoke and Heat Vents

910.3.1

ICC-ES AC 358—24: Acceptance Criteria for Helical Foundation Systems and Devices*

1810A.3.1.5.1, 1810.3.1.5.1

ICC-ES AC 446—24: Acceptance Criteria for Headed Cast-in Specialty Inserts in Concrete*

1617A.1.19, 1901.3.2

ICC 1100—2019: Standard for Spray-applied Foam Plastic Insulation

2603.1.1
CRC § 1.1 High relevance — show source text
CBC—25: California Building Code R101.2, R202, R301.1.1, R301.1.3, R301.2.1.1, R301.2.2.1.1, R301.2.2.1.2, R301.3, Table R302.1(1), Table R302.1(2), R302.2.1, R302.2.2, R302.3, R302.15.4, R322.1, R322.3, R324.5, R403.1.8, Table R602.10.3(3), Table R606.12.2.1, R609.2, R905.10.3

CEBC—25: California Existing Building Code [®]

R110.2, N1109.2

CFC—25: California Fire Code [®]

R102.6, R329.2, N1109.2, M2201.7, G2402.3, G2412.2

CWUIC—25: California Wildland-Urban Interface Code

R102.8, R337, R806.1.1, R907.1.1

ICC 400—2022: Standard on the Design and Construction of Log Structures

R301.1.1, R502.1.4, R602.1.4, R703.1, R802.1.3

ICC 500—2020: ICC/NSSA Standard for the Design and Construction of Storm Shelters

R307.1

ICC 600—2020: 2020 Standard for Residential Construction in High-Wind Regions

R301.2.1.1

ICC 1100—2019: Standard for Spray-applied Polyurethane Foam Plastic Insulation

R303.1.1

IPMC—24: International Property Maintenance Code [®]

R102.6

ISO International Organization for Standardization Chemin de Blandonnet 8 Geneva, Switzerland CP 401 - 1214

8336—2009: Fibre-cement Flat Sheets—Product Specification and Test Methods Table R503.2.1.1(1), Table R503.2.1.1(2), Table R602.3(2), Table R702.4.2, R703.10.1, R703.10.2

44-16 2025 CALIFORNIA RESIDENTIAL CODE

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REFERENCED STANDARDS

NFPA National Fire Protection Association 1 Batterymarch Park Quincy, MA 02169-7471

13D— 25 : Standard for the Installation of Sprinkler Systems in One- and Two-Family Dwellings and Manufactured Homes as amended*

R309.1.1, R309.2.1, R309.3.1, R309.3.1.1, R309.3.2.3, R309.3.6.1, R329.6.2.1

*See California Fire Code for amendments

*NFPA 13D, Amended Sections as follows:

CFC § 2025 High relevance — show source text

Any repair, alteration or change of use undertaken within the relocated structure shall comply with the requirements of this code applicable to the work being performed.
Any field fabricated elements shall comply with the applicable requirements of this code.

SECTION BO108—REFERENCED STANDARDS

BO108.1 General. See Table BO108.1 for standards that are referenced in various sections of this appendix. Standards are listed by the standard identification with the effective date, the standard title and the section or sections of this appendix that reference the standard.

TABLE BO108.1—REFERENCED STANDARDS	Col2	Col3
STANDARD ACRONYM	STANDARD NAME	SECTION HEREIN REFERENCED
CEBC—25	California Existing Building Code	BO102.8
CFC—25	California Fire Code	BO107.1
IPMC—24	International Property Maintenance Code®	BO107.1

APPENDIX BO-6 2025 CALIFORNIA RESIDENTIAL CODE

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CA RESERVED

2025 CALIFORNIA RESIDENTIAL CODE APPENDIX CA-1

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APPENDIX CA-2 2025 CALIFORNIA RESIDENTIAL CODE

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CB RESERVED

2025 CALIFORNIA RESIDENTIAL CODE APPENDIX CB-1

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APPENDIX CB-2 2025 CALIFORNIA RESIDENTIAL CODE

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CC RESERVED

2025 CALIFORNIA RESIDENTIAL CODE APPENDIX CC-1

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APPENDIX CC-2 2025 CALIFORNIA RESIDENTIAL CODE

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CD RESERVED

2025 CALIFORNIA RESIDENTIAL CODE APPENDIX CD-1

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APPENDIX CD-2 2025 CALIFORNIA RESIDENTIAL CODE

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CE RESERVED

2025 CALIFORNIA RESIDENTIAL CODE APPENDIX CE-1

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APPENDIX CE-2 2025 CALIFORNIA RESIDENTIAL CODE

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CF RESERVED

2025 CALIFORNIA RESIDENTIAL CODE APPENDIX CF-1

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APPENDIX CF-2 2025 CALIFORNIA RESIDENTIAL CODE

CRC § 4.1.3 High relevance — show source text

Col1	Col2
81~~/ "~~	81~~/ "~~

2025 CALIFORNIA EXISTING BUILDING CODE RESOURCE A-109

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 4.1.3 REINFORCED CONCRETE BEAMS DEPTH 14″ TO LESS THAN 16″	Col2	Col3	Col4	Col5	Col6	Col7	Col8	Col9	Col10
ITEM CODE	DEPTH	CONSTRUCTION DETAILS	PERFORMANCE	PERFORMANCE	REFERENCE NUMBER	REFERENCE NUMBER	REFERENCE NUMBER	NOTES	REC. HOURS
ITEM CODE	DEPTH	CONSTRUCTION DETAILS	LOAD	TIME	PRE-BMS-92	BMS-92	POST-BMS-92	POST-BMS-92	POST-BMS-92
B-15-RC-1	15″	Concrete flange: 4″ deep × 2' wide (3290 psi) concrete; concrete beam: 10″ deep × 81/2″ wide; “I” beam reinforcement: 10″ × 41/2″ × 25 lbs R.S.J.; 4″ cover on bottom flange; 1″ cover on top flange; flange reinforcement:3/8″ diam- eter bars at 6″ pitch parallel to “T”;1/4″ diameter bars perpendicular to “T”; beam reinforcement: 4″ × 6″ No. 13 SWG wire mesh; span: 11′ restrained.	10 tons	6 hrs			7	1–3, 5, 6	4
B-15-RC-2	15″	Concrete flange: 4″ deep × 2' wide (4820 psi) concrete; concrete beam: 10″ deep × 81/2″ wide; “I” beam reinforcement: 10″ × 41/2″ × 25 lbs R.S.J.; 1″ cover over wire mesh on bottom flange; 1″ cover on top flange; flange rein- forcement:3/8″ diameter bars at 6″ pitch parallel to “T”;1/4″ diameter bars perpendicu- lar to “T”; beam reinforcement: 4″ × 6″ No. 13 SWG wire mesh; span: 11′ restrained.	10 tons	6 hrs			7	1, 2, 4–6	4

For SI: 1 inch = 25.4 mm, 1 foot = 305 mm, 1 pound = 0.004448 kN, 1 pound per square inch = 0.00689 MPa, 1 ton = 8.896 kN.

Notes:

Load concentrated at mid-span.
Achieved 6-hour fire rating (Grade “A,” British).

CRC § 6.1507 High relevance — show source text
LIFT = Entering Condenser Water Temperature (°F) – Leaving Chilled Water Temperature (°F)
2. Condenser DT = Leaving Condenser Water Temperature (°F) – Entering Condenser Water Temperature (°F)
Kadj = 6.1507 – 0.30244(×) + 0.0062692(×)2 – 0.000045595(×)3
where× = Condenser DT + LIFT
COPadj = Kadj * COPstd|1. LIFT = Entering Condenser Water Temperature (°F) – Leaving Chilled Water Temperature (°F)
2. Condenser DT = Leaving Condenser Water Temperature (°F) – Entering Condenser Water Temperature (°F)
Kadj = 6.1507 – 0.30244(×) + 0.0062692(×)2 – 0.000045595(×)3
where× = Condenser DT + LIFT
COPadj = Kadj * COPstd|1. LIFT = Entering Condenser Water Temperature (°F) – Leaving Chilled Water Temperature (°F)
2. Condenser DT = Leaving Condenser Water Temperature (°F) – Entering Condenser Water Temperature (°F)
Kadj = 6.1507 – 0.30244(×) + 0.0062692(×)2 – 0.000045595(×)3
where× = Condenser DT + LIFT
COPadj = Kadj * COPstd|1. LIFT = Entering Condenser Water Temperature (°F) – Leaving Chilled Water Temperature (°F)
2. Condenser DT = Leaving Condenser Water Temperature (°F) – Entering Condenser Water Temperature (°F)
Kadj = 6.1507 – 0.30244(×) + 0.0062692(×)2 – 0.000045595(×)3
where× = Condenser DT + LIFT
COPadj = Kadj * COPstd|1. LIFT = Entering Condenser Water Temperature (°F) – Leaving Chilled Water Temperature (°F)
2. Condenser DT = Leaving Condenser Water Temperature (°F) – Entering Condenser Water Temperature (°F)
Kadj = 6.1507 – 0.30244(×) + 0.0062692(×)2 – 0.000045595(×)3
where× = Condenser DT + LIFT
COPadj = Kadj * COPstd|1. LIFT = Entering Condenser Water Temperature (°F) – Leaving Chilled Water Temperature (°F)
2. Condenser DT = Leaving Condenser Water Temperature (°F) – Entering Condenser Water Temperature (°F)
Kadj = 6.1507 – 0.30244(×) + 0.0062692(×)2 – 0.000045595(×)3
where× = Condenser DT + LIFT
COPadj = Kadj * COPstd|

A6.207.1.2 Controls for heat pumps with supplementary electric resistance heaters. Heat pumps with supplementary electric resistance heaters shall have controls:

A6.207.1.2.1 That prevent supplementary heater operation when the heating load can be met by the heat pump alone; and

CRC § 802-2014 High relevance — show source text

358 2025 CALIFORNIA PLUMBING CODE

REFERENCED STANDARDS

TABLE 1701.2 (continued) STANDARDS, PUBLICATIONS, PRACTICES, AND GUIDES

DOCUMENT NUMBER	DOCUMENT TITLE	APPLICATION
MSS SP-123-2018	Non-Ferrous Threaded and Solder-Joint Unions for Use with Copper Water Tube	Joints
NFPA	NFPA	NFPA
NFPA 13R-2022	Standard for the Installation of Sprinkler Systems in Low-Rise Residential Occupan- cies	Miscellaneous
NFPA 80-2022	Standard for Fire Doors and Other Opening Protectives	Miscellaneous
NFPA 501A-2021	Standard for Fire Safety Criteria for Manufactured Home Installations, Sites, and Communities	Miscellaneous
NFPA 1981-2019	Standard on Open-Circuit Self-Contained Breathing Apparatus (SCBA) for Emer- gency Services	Miscellaneous
NFPA 1989-2019	Standard on Breathing Air Quality for Emergency Services Respiratory Protection	Miscellaneous
NFPA 5000-2021	Building Construction and Safety Code	Miscellaneous
NSF	NSF	NSF
NSF/ANSI 2-2019	Food Equipment	Appliances
NSF/ANSI 4-2020	Commercial Cooking, Rethermalization,

CRC § 6.9 High relevance — show source text
R324.6.9, R609.3

FM FM Approvals Headquarters Office Norwood, MA 02062

4474—2020: American National Standard for Evaluating the Simulated Wind Uplift Resistance of Roof Assemblies Using Static Positive and/or Negative Differential Pressures

R905.4.4.1, R905.9.4, R905.10.5, R905.11.4, R905.12.4, R905.13.4, R905.14.4

ANSI/FM 4880—(2017): American National Standard for Evaluating the Fire Performance of Insulated Building Panel Assemblies and Interior Finish Materials

R303.6

GA Gypsum Association 6525 Belcrest Road, Suite 480 Hyattsville, MD 20782

GA-253—2021: Application of Gypsum Sheathing Table R602.3(1)

IAPMO IAPMO Group 4755 E. Philadelphia Street Ontario, CA 91761-USA

CMC—25: California Mechanical Code

R325.2, R325.2.1, R325.3, R325.4.1, R330.9. R408.3, R408.4, R807.1, R1003.11.3, R1003.14

CPC—25: California Plumbing Code R309.3.1.1, R309.3.2.3, Table R309.3.6.2(1), R309.3.8.1, R327.1, R329.2, R903.4.1

ICC International Code Council, Inc. 200 Massachusetts Avenue, NW, Suite 250 Washington, DC 20001

CBC—25: California Building Code R101.2, R202, R301.1.1, R301.1.3, R301.2.1.1, R301.2.2.1.1, R301.2.2.1.2, R301.3, Table R302.1(1), Table R302.1(2), R302.2.1, R302.2.2, R302.3, R302.15.4, R322.1, R322.3, R324.5, R403.1.8, Table R602.10.3(3), Table R606.12.2.1, R609.2, R905.10.3

CEBC—25: California Existing Building Code [®]

R110.2, N1109.2

CFC—25: California Fire Code [®]

R102.6, R329.2, N1109.2, M2201.7, G2402.3, G2412.2

CWUIC—25: California Wildland-Urban Interface Code

R102.8, R337, R806.1.1, R907.1.1

ICC 400—2022: Standard on the Design and Construction of Log Structures

R301.1.1, R502.1.4, R602.1.4, R703.1, R802.1.3

ICC 500—2020: ICC/NSSA Standard for the Design and Construction of Storm Shelters

R307.1

ICC 600—2020: 2020 Standard for Residential Construction in High-Wind Regions

R301.2.1.1
CRC § 2103.4 High relevance — show source text
Reinforcement

Masonry 2103.4 Shotcrete 1908 Religious Worship, Places of Accessibility Chapter 11B Alarms and detection 907.2.1 Balcony 1030.5 Classification 303.1.4, 303.4, 305.1.1, 305.2.1, 308.5.2 Door operations 1010.2.9 Egress 1030 Interior finishes Table 803.13, 804 Unlimited area 507.6, 507.7 Relocating, Building 101.4.7, 107.2.8, 3113 Compliance 3113.1.1 Inspection agencies 3113.4 Manufacturer’s data plate 3113.3 Supplemental information 3113.2 Repairs, Building 101.4.7, 202 Flood 1612.1

Minor 105.2.2

Permit required 105.1 Roof, Reroofing 1509, 1512 Residential Hotels (mail receptacles) 420.13.1 Residential Occupancy (Group R) 310 Accessibility Chapter 11A, 11B Alarm and detection 907.2.8, 907.2.9, 907.2.11, 907.2.12, 907.5.2.3.2,

907.5.2.3.3

Area 503, 505, 506, 508, 510 Carbon monoxide alarms 915 Cooking 420.10, 420.11 Draftstopping 708.4.3, 718.4 Group provisions Group R-1 (transient) 310.2 Group R-2 (apartment) 310.3 Group R-3 (two dwellings per building) 310.4 Group R-4 (group homes) 310.5 Electric vehicle charging 420.14 Height 503, 504, 505, 508, 510 Incidental uses 509

Interior finishes Table 803.13, 804 Live load Table 1607.1

Live/work units 508.5 Means of egress Aisles 1018.5

Corridors 1020.2, 1020.3

Doors 1010.1.1 Emergency escape and rescue 1031.2

Exit signs 1013.1, 1013.2 Single exits 1006.3 Stairway, exit access 1019 Travel distance 1006.3.3, 1017.2,

1006.2.1

Mixed occupancies 508.3, 508.4 Accessory 508.2, G112.1 Live/work units 508.5 Parking, private 406.2.8, 406.3 Parking below/above 510.4, 510.7, 510.9

Special mixed 510.2

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INDEX

Means of egress 3310 Protection of pedestrians 3306 Sanitary facilities 3305 Site work 3304

CRC § 1.5 High relevance — show source text

Adopting agency	BSC	BSC- CG	SFM	HCD	Col6	Col7	DSA	Col9	Col10	OSHPD	Col12	Col13	Col14	Col15	Col16	BSCC	DPH	AGR	DWR	CEC	CA	SL	SLC
Adopting agency	BSC	BSC- CG	SFM	1	2	1/AC	AC	SS	SS/CC	1	1R	2	3	4	5	5	5	5	5	5	5	5	5
Adopt entire chapter
Adopt entire chapter as amended (amended sections listed below)
Adopt only those sections that are listed below	X		X	X
Chapter / Section
R109.1.5			X	X
R109.1.5.1			X	X
R109.1.5.2				X
R109.1.5.3				X
R109.1.6			X	X
R109.1.6.1				X
R109.1.6.2				X
R109.2 - R109.4			X
R110 - R110.4			X
R111 - R111.3			X
R113.1 - R113.2			X
R114.1 - R114.4			X

The state agency does not adopt sections identified with the following symbol: †

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PART I—ADMINISTRATIVE

1 ADMINISTRATION

DIVISION I CALIFORNIA ADMINISTRATION

SECTION 1.1—GENERAL

1.1.1 Title. These regulations shall be known as the California Residential Code, may be cited as such and will be referred to herein as “this code.” The California Residential Code is Part 2.5 of thirteen parts of the official compilation and publication of the adoption, amendment and repeal of building regulations to the California Code of Regulations, Title 24, also referred to as the California Building Standards Code. This part incorporates by adoption the 2024 International Residential Code of the International Code Council with necessary California amendments.

CRC § 208.3.1 High relevance — show source text
11B- 208.3.1 General. Parking spaces complying with Section 11B- 502 that serve a particular building or facility shall be located on the shortest accessible route from parking to an entrance complying with Section 11B- 206.4. Where parking serves more than one accessible entrance, parking spaces complying with Section 11B- 502 shall be dispersed and located on the shortest accessible route to the accessible entrances. In parking facilities that do not serve a particular building or facility, parking spaces complying with Section 11B- 502 shall be located on the shortest accessible route to an accessible pedestrian entrance of the parking facility.

Exceptions:
1. All van parking spaces shall be permitted to be grouped on one level within a multistory parking facility.
2. Parking spaces shall be permitted to be located in different parking facilities if substantially equivalent or greater accessibility is provided in terms of distance from an accessible entrance or entrances, parking fee and user convenience.
11B- 208.3.2 Residential facilities. In residential facilities containing residential dwelling units required to provide mobility features complying with Sections 11B- 809.2 through 11B- 809.4, and adaptable features complying with Sections 11B-809.6 through 11B-809.12, parking spaces provided in accordance with Section 11B- 208.2.3.1 shall be located on the shortest accessible route to

2025 CALIFORNIA BUILDING CODE 11B-17

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ACCESSIBILITY TO PUBLIC BUILDINGS, PUBLIC ACCOMMODATIONS, COMMERCIAL BUILDINGS AND PUBLIC HOUSING

the residential dwelling unit entrance they serve. Spaces provided in accordance with Section 11B- 208.2.3.2 shall be dispersed throughout all types of parking provided for the residential dwelling units.

Exception: Parking spaces provided in accordance with Section 11B- 208.2.3.2 shall not be required to be dispersed throughout all types of parking if substantially equivalent or greater accessibility is provided in terms of distance from an accessible entrance, parking fee and user convenience.

11B-208.3.3 Private garages accessory to residential dwelling units. Private garages accessory to residential dwelling units shall comply with Section 11B-208.3. Private garages include individual garages and multiple individual garages grouped together.

11B-208.3.3.1 Detached private garages accessory to residential dwelling units shall be accessible as required by Section 11B- 208.3.

11B-208.3.3.2 Attached private garages directly serving a single residential dwelling unit shall provide at least one of the follow- ing options:

1. A door leading directly from the residential dwelling unit which immediately enters the garage.

2. An accessible route from the residential dwelling unit to an exterior door entering the garage.

3. An accessible route from the residential dwelling unit's primary entry door to the vehicular entrance at the garage.

SECTION 11B- 209—PASSENGER DROP-OFF AND LOADING ZONES AND BUS STOPS

11B- 209.1 General. Passenger drop-off and loading zones shall be provided in accordance with Section 11B- 209 .
CRC § 1.8.10 High relevance — show source text
Division 1, Chap-_ ter 3, Subchapter 1, commencing with Section 3000.

SECTION 1.8.10—OTHER BUILDING REGULATIONS

1.8.10.1 Existing structures. Notwithstanding other provisions of law, the replacement, retention and extension of original materials and the use of original methods of construction for any existing building or accessory structure, or portions thereof, shall be permitted in accordance with the provisions of this code and the California Existing Building Code, as adopted by the Department of Housing and Community Development. For additional information, see California Health and Safety Code, Sections 17912, 17920.3, 17922 and 17958.8.

1.8.10.2 Moved structures. Subject to the requirements of California Health and Safety Code Sections 17922, 17922.3 and 17958.9, local ordinances or regulations relating to a moved residential building or accessory structure thereto, shall permit the replacement, reten- tion and extension of original materials and the use of original methods of construction so long as the structure does not become or continue to be a substandard building.

SECTION 1.9—DIVISION OF THE STATE ARCHITECT

1.9.1 Division of the State Architect—Access Compliance.

General. The purpose of this code is to ensure that barrier-free design is incorporated in all buildings, facilities, site work and other improvements to which this code applies in compliance with state law to ensure that these improvements are accessible to and usable by persons with disabilities. Additions, alterations and structural repairs in all buildings and facilities shall comply with these provisions for new buildings, except as otherwise provided and specified herein.

The provisions of these regulations shall apply to any portable buildings leased or owned by a school district, and shall also apply to temporary and emergency buildings and facilities. Temporary buildings and facilities are not of permanent construction but are exten- sively used or are essential for public use for a period of time. Examples of temporary buildings or facilities covered include, but are not limited to: reviewing stands, temporary classrooms, bleacher areas, exhibit areas, temporary banking facilities, temporary health screening services or temporary safe pedestrian passageways around a construction site.

In addition, to incorporate standards at least as restrictive as those required by the federal government for barrier-free design under (1) Title III (Public Accommodations and Commercial Facilities), Subpart D (New Construction and Alteration) (see 28 C.F.R., Part 36), and (2) Title II (Public Entities), Section 35.151 (New Construction and Alterations) (see 28 C.F.R., Part 35) both from the Americans with Disabilities Act of 1990, 2004 Americans with Disabilities Act Accessibility Guidelines, as adopted by the U.S. Department of Justice (see 36 C.F.R. Part 1191, Appendices B and D), and (3) under the Fair Housing Amendments Act of 1988. Some of these regulations may be more stringent than state law in order to meet the federal requirement.

1.9.1.1 Application. See Government Code commencing with Section 4450.

Publicly funded buildings, structures, sidewalks, curbs and related facilities shall be accessible to and usable by persons with disabilities as follows:
CRC § 603.1 High relevance — show source text
Design Professional in Responsible Charge) Architectural Trim 603.1, 1408.3 Area, Building Chapter 5, 506, Table 506.2 Accessory uses 508.2.3 Aircraft hangars, residential 412.4.5 Allowable area determination 506.2,

506.3

Basements 506.1.3 Buildings on same lot 503.1.2 Covered and open mall building 402.4.1, 402.4.1.1 Enclosed parking garage 406.6.1, 510.3 Equipment platforms 505.3.1 Frontage bonus 506.3 Incidental uses 509.3

Limitations 503, 506 Membrane structures 3102.4

Mezzanines 505.2.1 Mixed construction types 3102.6 Mixed occupancy 508.2.3, 508.3.2, 508.4.2

Modifications 506, 510 Occupied roof 503.1.4 Open mall building 402.4.1 Open parking garage 406.5.4, 406.5.4.1, 406.5.5, 510.2, 510.3, 510.4, 510.7, 510.8, 510.9 Private garages and carports 406.3.1 Special provisions 510 Unlimited area 503.1.1, 503.1.3, 506.1.1, 506.2, 507 Area for Assisted Rescue, Exterior (see Exterior Area for Assisted Rescue) Area of Refuge (see Also Accessible Means of Egress) 202

Requirements 709.4.2, 1009.6 Signage 1009.10, 1009.11, 1009.9, 1013.4, 1143A, 11B-216, 11B-703 Two-way communication 1009.6.5, 1009.8, 1026.6 Where required 1009.2, 1009.3.3, 1009.4.2 Assembly Occupancy (Group A) 303, 1030 Accessibility Chapters 11A and 11B Alarms and detection 907.2.1

Area 503, 506, 507, 508 Bleachers (see Bleachers) Folding and telescopic seating (see Bleachers) General 303.1 Grandstands (see Grandstands) Group-specific provisions A-1 303.2

A-2 303.3

A-3 303.4

A-4 303.5

Motion picture theater 409, 507.12 Special amusement areas 411 Stages and platforms 410 Height 503, 504, 505, 508, 510 Incidental uses 509 Interior finishes Table 803.13, 804 Live load Table 1607.1 Means of egress Aisles 1018.2, 1030.9, 1030.10,

1030.11

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INDEX
CRC § 502.4 High relevance — show source text
Exception: Buildings of Group R occupancy with not more than five dwelling or sleeping units used solely for residential purposes where the existing building and the addition together comply with the conventional light-frame construction methods of the Cali- fornia Building Code or the provisions of the California Residential Code .

[BS] 502.4 Existing structural elements carrying lateral load. Where the addition is structurally independent of the existing structure, existing lateral load-carrying structural elements shall be permitted to remain unaltered. Where the addition is not structurally independent of the existing structure, the lateral force-resisting system of the existing structure and its addition acting together as a single structure shall comply with Section 1609 of the California Building Code and with Section 304.3.1 of this code.

Exceptions:
1. Any existing lateral load-carrying structural element whose demand-capacity ratio with the addition considered is not more than 10 percent greater than its demand-capacity ratio with the addition ignored shall be permitted to remain unaltered. For purposes of calculating demand-capacity ratios, the demand shall consider applicable load combinations with design lateral loads or forces in accordance with Sections 1609 and 1613 of the California Building Code . For purposes of this exception, comparisons of demand-capacity ratios and calculation of design lateral loads, forces and capacities shall account for the cumulative effects of additions and alterations since original construction. When calcu
5-4 2025 CALIFORNIA EXISTING BUILDING CODE

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PRESCRIPTIVE COMPLIANCE METHOD

lating demand-capacity ratios for wind, the date of original construction shall be permitted to be taken as the date of completion of a prior addition, alteration or repair in compliance with Section 1609 of the California Building Code or the code wind forces in effect at the time. When calculating demand-capacity ratios for earthquake, the date of original construction shall be permitted to be taken as the date of completion of a prior addition, alteration or repair in compliance with Section 304.3.1 or the full seismic forces in effect at the time.
1. Buildings of Group R occupancy with not more than five dwelling or sleeping units used solely for residential purposes where the existing building and the addition together comply with the conventional light-frame construction methods of the California Building Code or the provisions of the California Residential Code .
502.5 Smoke barriers in Group R-2.1 . Where an addition to an existing Group R-2.1 building adds sleeping areas that result in more than 50 care recipients on a story, smoke barriers shall be provided to subdivide such story into not fewer than two smoke compartments in accordance with Section 420.6 of the California Building Code .

Exception: Where the existing building is divided into smoke compartments and the addition does not result in any individual smoke compartment exceeding the size and travel distance requirements in Section 420.6 of the California Building Code, additional smoke barriers are not required.

502.6 Enhanced classroom acoustics. In Group E occupancies, enhanced classroom acoustics shall be provided in all classrooms in the addition with a volume of 20,000 cubic feet (565 m [3] ) or less. Enhanced classroom acoustics shall comply with the reverberation time in Section 808 of ICC A117.1.

SECTION 503—ALTERATIONS

Frequently asked questions

What edition of A117.1 does the CRC reference?

The CRC references ICC A117.1 — 2017 for the CRC sections listed in the referenced‑standards table.

Does A117.1 apply to every residential accessibility requirement?

No. The CRC adopts A117.1‑2017 only where an individual CRC section explicitly references it (for example § 502.6, § 503.18, § 1011.4, § 1101.6). Check the CRC section text first.

For acoustics, what is the numeric trigger that makes A117.1 § 808 apply?

If the classroom (addition) volume is 20,000 cubic feet or less, § 502.6 requires compliance with the reverberation‑time limits in ICC A117.1 § 808.

I only have the A117.1‑2021 edition — can I use that?

The CRC points to A117.1‑2017; do not substitute a later edition without approval from the enforcing agency. The CRC’s referenced‑standards table specifies the edition.

Where can I find the exact CRC wording for § 503.18, § 1011.4 or § 1101.6?

The provided files show the CRC’s referenced‑standards table linking those sections to A117.1‑2017, but the full text of those three CRC sections was not retrieved in the uploaded materials I examined. You should consult the official CRC text for the verbatim section language.

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What standards apply to bleachers, folding and telescopic seating and grandstands?

Which standard is referenced for storm shelter design and construction?

Accessibility, egress and special-occupancy referenced standards

California Residential Code

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What the code requires — plain English

Requirements in detail

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Decision‑relevant dimensions and values

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Worked example — concrete numbers

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Code references

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CA RESERVED

CB RESERVED

CC RESERVED

CD RESERVED

CE RESERVED

CF RESERVED

1 ADMINISTRATION

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