Title 24 · California Energy Code

Where are Part 6 definitions and rules of construction located?

Section 100.1 of the California Energy Code (Part 6) is where you find the rules of construction and the primary list of defined Part 6 terms; if a term is not in § 100.1, check the Definitions in Title 24 Parts 1–5, then Webster’s Third dictionary as a last resort.

Ask a question free See coverage

Last reviewed: July 6, 2026

What the code requires — 2-4 sentences

The definitions and rules of construction that govern Part 6 (the California Energy Code) are located in § 100.1. § 100.1 prescribes three basic rules of construction (singular/plural, use of “and” vs “or”, and the force of “shall” vs “may”) and then establishes the hierarchy for meanings of terms used in Part 6: first § 100.1 itself, then the Definitions chapters of Title 24, Parts 1–5, and finally Webster’s Third New International Dictionary if no regulatory definition exists.

The single most important rule: Part 6 terms are defined first in § 100.1; if a term is not there, consult the Definitions chapters in Title 24, Parts 1–5; if still undefined, the code uses Webster’s Third unless the context requires otherwise.

Requirements in detail

Rules of construction (plain-language)

Singular/plural rule — the singular includes the plural and the plural includes the singular when the context requires. § 100.1 explains this as a general interpretive rule.
“And” versus “or” — the word “and” in a conjunctive provision means all listed elements must exist or be complied with; where only one or more elements suffice, “or” (not “and/or”) is used. § 100.1 requires reading conjunctive language strictly unless the provision says otherwise.
Mandatory/Permissive — “shall” is mandatory; “may” is permissive. This dictates whether a provision creates a requirement or an option. § 100.1 states this rule directly.

Definitions: where to look (hierarchy)

First: the list of defined Terms inside § 100.1 itself (Part 6 definitions).
Second: the “Definitions” chapters of Title 24, Parts 1–5 if a term isn’t in § 100.1.
Third: if neither regulatory source defines the term, the meaning is taken from Webster’s Third New International Dictionary, Unabridged (1961 ed., through 2002 addenda), unless context requires otherwise.

Representative defined terms (first occurrences bolded)

ADDITION — any change that increases conditioned floor area and conditioned volume; also applies to changes increasing floor area and volume of an unconditioned building type regulated by Part 6, and to increases in illuminated area of outdoor lighting applications. § 100.1 defines this term.
ACCESSIBLE, AAMA/WDMA/CSA 101/I.S.2/A440-17, ACCA, ACCA MANUAL J, and other standards or acronyms are defined in § 100.1 where applicable.

Decision table — quick reference

Decision point	What the code requires / how to apply it	Code Reference
Which text defines a Part 6 term?	Check § 100.1 first; if not found, check Definitions in Title 24, Parts 1–5; if still undefined, use Webster’s Third unless context dictates otherwise.	§ 100.1
If a provision uses “and”	Treat as conjunctive: all elements must be met to apply the provision.	§ 100.1(a).2
If a provision uses “or”	One or more elements suffice; use “or” where not all elements are required.	§ 100.1(a).2
Does “shall” create an obligation?	Yes — “shall” is mandatory; “may” is permissive.	§ 100.1(a).3
Where to find referenced standards (e.g., AAMA)?	Many referenced standards and acronyms are named and defined directly in § 100.1.	§ 100.1 (Definitions)

Exceptions & special cases

The code explicitly allows context to modify the ordinary rules: if context requires otherwise, the singular/plural or dictionary meaning can be adjusted. This is stated in § 100.1 (rules and definitions).
When Part 6 references manufactured equipment, administrative matters, or certification, it points users to other Parts or Title 20/Part 1 administrative sections for details (see the surrounding Part 6 text referencing administrative/certification requirements). For related administrative cross-references, see the Code’s table of contents and section references (e.g., § 100.0, § 110.0) in the Part 6 front matter.

Common mistakes

Treating “may” as if it were mandatory — the code makes the distinction explicit: “shall” mandatory, “may” permissive. § 100.1(a).3 clarifies this.
Misreading “and” as permissive (i.e., reading “and” like “or” or “and/or”). The code requires stricter conjunctive reading unless the provision explicitly allows alternatives. § 100.1(a).2.
Failing to check the Definitions chapters in Title 24, Parts 1–5 when a term is not in § 100.1 — the code directs users to those Parts as the second source for meanings. § 100.1(b).
Assuming every common construction term uses ordinary-English meaning rather than the specific regulatory definition or dictionary specified by § 100.1. Always verify the definition hierarchy.

Worked example — concrete scenario

Scenario: An existing retail space has 1,000 ft² conditioned floor area. The owner remodels and adds an enclosed, air‑conditioned sales room of 150 ft².

Question: Is this work an ADDITION under Part 6?
Application: § 100.1 defines ADDITION as any change that increases conditioned floor area and conditioned volume. Because the project increases conditioned floor area from 1,000 ft² to 1,150 ft², it meets the definition of ADDITION and therefore the Part 6 rules for additions apply (including any Part 6 compliance steps tied to additions). § 100.1 provides the definition and directs you to treat this as an addition.

(If the term conditioned floor area needed further clarification, the next step per § 100.1 would be to check the Definitions chapters of Title 24, Parts 1–5.)

Related provisions

§ 100.0 — Scope and front‑matter (context for application of Part 6).
§ 110.0 — Systems and Equipment — General (mandatory measures and referenced enforcement topics that Part 6 cross‑references).
Title 24, Parts 1–5 — Definitions chapters (second-level source for term meanings when § 100.1 does not define a term).
Administrative cross-references (e.g., Title 24, Part 1 Sections 10-101 to 10-114) — for administrative requirements noted in Part 6.

Code references

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

§ 25218.5 High relevance — show source text
Note: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code . Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.5, 25402.8, and 25943, Public Resources Code .

SECTION 100.1 — DEFINITIONS AND RULES OF CONSTRUCTION

(a) Rules of Construction.
1. Where the context requires, the singular includes the plural and the plural includes the singular.
2. The use of “and” in a conjunctive provision means that all elements in the provision must be complied with or must exist to make the provision applicable. Where compliance with one or more elements suffices, or where existence of one or more elements makes the provision applicable, “or” (rather than “and/or”) is used.
3. “Shall” is mandatory and “may” is permissive.
(b) Definitions. Terms, phrases, words and their derivatives in Part 6 shall be defined as specified in Section 100.1. Terms, phrases, words and their derivatives not found in Section 100.1 shall be defined as specified in the “Definitions” chapters of Title 24, Parts 1 through 5 of the California Code of Regulations. Where terms, phrases, words and their derivatives are not defined in any of the references above, they shall be defined as specified in Webster’s Third New International Dictionary of the English Language, Unabridged (1961 edition, through the 2002 addenda), unless the context requires otherwise.

AAMA/WDMA/CSA 101/I.S.2/A440-17 are the American Architectural Manufacturers Association/Window and Door Manufacturers Association/Canadian Standards Association document titled “North American Fenestration Standard/Specification for windows, doors, and skylights” (2017).

ACCA is the Air Conditioning Contractors of America.

ACCA MANUAL J is the Air Conditioning Contractors of America document titled “Manual J-Residential Load Calculation,” (ANSI/ACCA 2 Manual J – 2016).

ACCEPTANCE REQUIREMENTS FOR CODE COMPLIANCE is a description of test procedures in the Reference Nonresidential Appendices that includes equipment and systems to be tested, functions to be tested, conditions under which the test shall be performed, the scope of the tests, results to be obtained and measurable criteria for acceptable performance.

ACCESSIBLE is having access thereto, but which first may require removal or opening of access panels, doors or similar obstructions.

ADDITION is any change to a building that increases conditioned floor area and conditioned volume. See also, “newly conditioned space.” Addition is also any change that increases the floor area and volume of an unconditioned building of an occupancy group or type regulated by Part 6. Addition is also any change that increases the illuminated area of an outdoor lighting application regulated by Part 6.

ADIABATIC PAD is a material located before the heat transfer surface of an adiabatic condenser, which precools the ambient air by becoming fully wetted during precool mode operation.

AGRICULTURAL BUILDING is a structure designed and constructed to house farm implements, hay, grain, poultry, livestock or other horticultural products. It is not a structure that is a place of human habitation, a place of employment where agricultural products are processed, treated or packaged, or a place used by the public.

AHAM is the Association of Home Appliance Manufacturers.
California Energy Code High relevance — show source text
Chapter 1 Scope and Administration.

Chapter 1 establishes the limits of applicability of the code and describes how the code is to be applied and enforced. The provisions of Chapter 1 establish the authority and duties of the code official appointed by the authority having jurisdiction and also establish the rights and privileges of the design professional, contractor and property owner.

Chapter 2 Definitions.

Chapter 2 is the repository of the definitions of terms used in the body of the code. The user of the code should be familiar with and consult this chapter because the definitions are essential to the correct interpretation of the code and because the user may not be aware that a term is defined.

Chapter 3 Building Planning.

Chapter 3 provides guidelines for a minimum level of structural integrity, life safety, fire safety and livability for inhabitants of dwelling units regulated by this code. Chapter 3 is a compilation of the code requirements specific to the building planning sector of the design and construction process. This chapter sets forth code requirements dealing with light, ventilation, sanitation, minimum room size, ceiling height and environmental comfort. Chapter 3 establishes life-safety provisions including limitations on glazing used in hazardous areas, specifications on stairways, use of guards at elevated surfaces, window and fall protection, and rules for means of egress. Snow, wind and seismic design live and dead loads and flood-resistant construction, as well as solar energy systems are addressed in this chapter.

Chapter 4 Foundations.

Chapter 4 provides the requirements for the design and construction of foundation systems for buildings regulated by this code. Provisions for seismic load, flood load and frost protection are contained in this chapter. A foundation system consists of two interdependent components: the foundation structure itself and the supporting soil.

The prescriptive provisions of this chapter provide requirements for constructing footings and walls for foundations of wood, masonry, concrete and precast concrete. In addition to a foundation’s ability to support the required design loads, this chapter addresses several other factors that can affect foundation performance. These include controlling surface water and subsurface drainage, requiring soil tests where conditions warrant and evaluating proximity to slopes and minimum depth requirements. The chapter also provides requirements to minimize adverse effects of moisture, decay and pests in basements and crawl spaces.

Chapter 5 Floors.

Chapter 5 provides the requirements for the design and construction of floor systems that will be capable of supporting minimum required design loads. This chapter covers four different types: wood floor framing, wood floors on the ground, cold-formed steel floor framing and concrete slabs on the ground. Allowable span tables are provided that greatly simplify the determination of joist, girder and sheathing sizes for raised floor systems of wood framing and cold-formed steel framing. This chapter also contains prescriptive requirements for wood-framed exterior decks and their attachment to the main building.

Chapter 6 Wall Construction.

Chapter 6 contains provisions that regulate the design and construction of walls. The wall construction covered in Chapter 6 consists of five different types: wood framed, cold-formed steel framed, masonry, concrete and structural insulated panel (SIP). The primary concern of this chapter is the structural integrity of wall construction and transfer of all imposed loads to the supporting structure. This chapter provides the requirements for the design and construction of wall systems that are capable of supporting the minimum design vertical loads (dead, live and snow loads) and lateral loads (wind or seismic loads). This chapter contains the prescriptive requirements for wall bracing and/or shear walls to resist t
§ 323-9843 High relevance — show source text
State Librarian [SL]

library.ca.gov csllaw@library.ca.gov (916) 323-9843 Public Library Construction & Renovation

2025 CALIFORNIA ENERGY CODE v

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

HOW TO DETERMINE WHERE CHANGES HAVE BEEN MADE

Symbols in the margins indicate where changes have been made or language has been deleted.

This symbol indicates that a change has been made.
- This symbol indicates deletion of language.
vi 2025 CALIFORNIA ENERGY CODE

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

CONTENTS

ADMINISTRATIVE REGULATIONS . . . . . . . . . . . . . . . . . . . . . . . . 1

CALIFORNIA CODE OF REGULATIONS TITLE 24, PART 6 . . . . . 1

SUBCHAPTER 1 ALL OCCUPANCIES—GENERAL PROVISIONS . . .1

100.0 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

100.1 Definitions and Rules of Construction . . . . . . . . . . . . . 4

100.2 Calculation of Energy Budgets. . . . . . . . . . . . . . . . . . . 36

SUBCHAPTER 2 ALL OCCUPANCIES—MANDATORY

REQUIREMENTS FOR THE MANUFACTURE, CONSTRUCTION AND INSTALLATION OF SYSTEMS, EQUIPMENT AND

BUILDING COMPONENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39

110.0 Systems and Equipment—General . . . . . . . . . . . . . . . 39

110.1 Mandatory Requirements for Appliances . . . . . . . . . 39

110.2 Mandatory Requirements for Space-Conditioning Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

110.3 Mandatory Requirements for Service Water-Heating Systems and Equipment . . . . . . . . . . . . . . . . . . . . . . . 52

110.4 Mandatory Requirements for Pool and Spa Systems and Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

110.5 Natural Gas Central Furnaces, Cooking Equipment, Pool and Spa Heaters, and Fireplaces: Pilot Lights Prohibited. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

110.6 Mandatory Requirements for Fenestration Products and Exterior Doors . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

110.7 Mandatory Requirements to Limit Air Leakage . . . . 57

110.8 Mandatory Requirements for Insulation, Roofing Products and Radiant Barriers. . . . . . . . . . . . . . . . . . 57

110.9 Mandatory Requirements for Lighting Controls. . . . 59
§ 17980.12 High relevance — show source text
For enforcement related to accessory dwelling units, see Health and Safety Code_ Section 17980.12 operative until January 1, 2035. 2. For applications subject to the Mobilehome Parks Act as referenced in Section 1.8.3.2.2 of this code, refer to Health and Safety Code, Division 13, Part 2.1, commencing with Section 18200 and California Code of Regulations, Title 25, Division 1, Chapter 2, commencing with Section 1000. 3. For applications subject to the Special Occupancy Parks Act as referenced in Section 1.8.3.2.3 of this code, refer to Health and Safety Code, Division 13, Part 2.3, commencing with Section 18860 and California Code of Regulations, Title 25, Division 1, Chapter 2.2, commencing with Section 2000. 4. For applications subject to the Employee Housing Act as referenced in Section 1.8.3.2.4 of this code, refer to Health and Safety Code, Division 13, Part 1, commencing with Section 17000 and California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 3, commencing with Section 600. 5. For applications subject to the Factory-Built Housing Law as referenced in Section 1.8.3.2.5 of this code, refer to Health and Safety Code, Division 13, Part 6, commencing with Section 19960 and California Code of Regulations, Title 25, Division 1, Chap- ter 3, Subchapter 1, commencing with Section 3000.

1.8.9.2 Actions and proceedings. Subject to other provisions of law, punishments, penalties and fines for violations of building stan- dards are contained in the following statutes and regulations: 1. For applications subject to the State Housing Law as referenced in Section 1.8.3.2.1 of this code, refer to Health and Safety Code, Division 13, Part 1.5, commencing with Section 17910 and California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 1, commencing with Section 1. 2. For applications subject to the Mobilehome Parks Act as referenced in Section 1.8.3.2.2 of this code, refer to Health and Safety Code, Division 13, Part 2.1, commencing with Section 18200 and California Code of Regulations, Title 25, Division 1, Chapter 2, commencing with Section 1000. 3. For applications subject to the Special Occupancy Parks Act as referenced in Section 1.8.3.2.3 of this code, refer to the Health and Safety Code, Division 13, Part 2.3, commencing with Section 18860 and California Code of Regulations, Title 25, Division 1, Chapter 2.2, commencing with Section 2000. 4. For applications subject to the Employee Housing Act as referenced in Section 1.8.3.2.4 of this code, refer to Health and Safety Code, Division 13, Part 1, commencing with Section 17000 and California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 3, commencing with Section 600. _5.
§ 25.4 High relevance — show source text
× 10|21 × 7|17 × 6|14 × 6|12 × 6|12 × 6| |70 psf|3 story—slab-on-grade|29 × 11|22 × 7|17 × 6|14 × 6|12 × 6|12 × 6| |70 psf|3 story—with crawl space|31 × 12|23 × 8|19 × 6|16 × 6|13 × 6|12 × 6| |70 psf|3 story—plus basement|34 × 13|26 × 9|21 × 7|17 × 6|15 × 6|13 × 6| |For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 47.9 N/m2.
a. Linear interpolation of footing width is permitted between the soil bearing pressures in the table. Extrapolation is not permitted.
b. The table is based on the following conditions and loads: building width, 32 feet; wall height, 9 feet; basement wall height, 8 feet; dead loads, 15 psf roof and ceiling assembly,
10 psf floor assembly, 12 psf wall assembly; live loads, roof and ground snow loads as listed, 40 psf first floor, 30 psf second and third floors. Footing sizes are calculated
assuming a clear span roof/ceiling assembly and an interior bearing wall or beam at each floor.
c. Where the building width perpendicular to the wall footing is greater than 32 feet, the footing width shall be increased by 2 inches and footing depth shall be increased by 1
inch for every 4 feet of increase in building width.
d. Where the building width perpendicular to the wall footing is less than 32 feet, a 2-inch decrease in footing width and 1-inch decrease in footing depth is permitted for every 4
feet of decrease in building width provided that the minimum width is 12 inches and minimum depth is 6 inches.
SLAB
ON GRADE
BASEMENT
CRAWL
SPACE|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 47.9 N/m2.
a. Linear interpolation of footing width is permitted between the soil bearing pressures in the table. Extrapolation is not permitted.
b. The table is based on the following conditions and loads: building width, 32 feet; wall height, 9 feet; basement wall height, 8 feet; dead loads, 15 psf roof and ceiling assembly,
10 psf floor assembly, 12 psf wall assembly; live loads, roof and ground snow loads as listed, 40 psf first floor, 30 psf second and third floors. Footing sizes are calculated
assuming a clear span roof/ceiling assembly and an interior bearing wall or beam at each floor.
c. Where the building width perpendicular to the wall footing is greater than 32 feet, the footing width shall be increased by 2 inches and footing depth shall be increased by 1
inch for every 4 feet of increase in building width.
d.
§ 1.8.3.2 High relevance — show source text
For additional requirements regarding additions, alterations or repairs to existing buildings and appurtenant structures, see the Cali- fornia Existing Building Code.

1.8.3.2 Laws, rules and regulations. Other than the building standards contained in this code, and notwithstanding other provisions of law, the statutory authority and location of the laws, rules and regulations to be enforced by local enforcing agencies are listed by stat- ute in Sections 1.8.3.2.1 through 1.8.3.2.5 below:

1.8.3.2.1 State Housing Law. Refer to the State Housing Law, California Health and Safety Code, Division 13, Part 1.5, commencing with Section 17910 and California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 1, commencing with Section 1, for the erec- tion, construction, reconstruction, movement, enlargement, conversion, alteration, repair, removal, demolition or arrangement of apartments, condominiums, hotels, motels, lodging houses and dwellings, including accessory buildings, facilities and uses thereto.

1.8.3.2.2 Mobilehome Parks Act. Refer to the Mobilehome Parks Act, California Health and Safety Code, Division 13, Part 2.1, commencing with Section 18200 and California Code of Regulations, Title 25, Division 1, Chapter 2, commencing with Section 1000 for mobilehome park administrative and enforcement authority, permits, plans, fees, violations, inspections and penalties both within and outside mobilehome parks.

Exception: Mobilehome parks where the Department of Housing and Community Development is the enforcing agency.

1.8.3.2.3 Special Occupancy Parks Act. Refer to the Special Occupancy Parks Act, California Health and Safety Code, Division 13, Part 2.3, commencing with Section 18860 and California Code of Regulations, Title 25, Division 1, Chapter 2.2, commencing with Section 2000 for special occupancy park administrative and enforcement authority, permits, fees, violations, inspections and penal- ties both within and outside of special occupancy parks.

Exception: Special occupancy parks where the Department of Housing and Community Development is the enforcing agency.

1.8.3.2.4 Employee Housing Act. Refer to the Employee Housing Act, California Health and Safety Code, Division 13, Part 1, commencing with Section 17000 and California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 3, commencing with Section 600 for employee housing administrative and enforcement authority, permits, fees, violations, inspections and penalties.

1.8.3.2.5 Factory-Built Housing Law. Refer to the Factory-Built Housing Law, California Health and Safety Code, Division 13, Part 6, commencing with Section 19960 and California Code of Regulations, Title 25, Division 1, Chapter 3, Subchapter 1, commencing with Section 3000 for factory-built housing administrative and enforcement authority, permits, fees, violations, inspections and penalties.

SECTION 1.8.4—PERMITS, FEES, APPLICATIONS AND INSPECTIONS
§ 100.0 High relevance — show source text
Exception 1 to Section 100.0(f): If one occupancy constitutes at least 80 percent of the conditioned floor area of the building, the entire building envelope, HVAC and water heating may be designed to comply with the provisions of Part 6 applicable to that occupancy, provided that the applicable lighting requirements in Sections 140.6 through 140.8, 150.0(k), or 160.5 and 170.2(e) are met for each occupancy and space, and mandatory measures in Sections 110.0 through 130.5, 150.0, and 160.0 through 160.9 are met for each occupancy and space.

Exception 2 to Section 100.0(f): If one occupancy constitutes at least 90 percent of the combined conditioned plus unconditioned floor area of the building, the entire building indoor lighting may be designed to comply with only the lighting provisions of Part 6 applicable to that occupancy.

(g) Administrative requirements. Administrative requirements relating to permit requirements, enforcement by the Commission, locally adopted energy standards, interpretations, claims of exemption, approved calculation methods, rights of appeal, and certification and labeling requirements of fenestration products and roofing products are specified in California Code of Regulations, Title 24, Part 1, Sections 10-101 to 10-114.

(h) Certification requirements for manufactured equipment, products and devices. Part 6 limits the installation of manufactured equipment, products and devices to those that have been certified as specified by Sections 110.0 and 110.1. Requirements for manufactured equipment, products, and devices, when not specified in Title 24 Part 6, are specified in California Code of Regulations, Title 20, Sections 1601–1609.

Note: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code . Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.5, 25402.8, and 25943, Public Resources Code .

SECTION 100.1 — DEFINITIONS AND RULES OF CONSTRUCTION

(a) Rules of Construction.
1. Where the context requires, the singular includes the plural and the plural includes the singular.
2. The use of “and” in a conjunctive provision means that all elements in the provision must be complied with or must exist to make the provision applicable. Where compliance with one or more elements suffices, or where existence of one or more elements makes the provision applicable, “or” (rather than “and/or”) is used.
3. “Shall” is mandatory and “may” is permissive.
(b) Definitions. Terms, phrases, words and their derivatives in Part 6 shall be defined as specified in Section 100.1. Terms, phrases, words and their derivatives not found in Section 100.1 shall be defined as specified in the “Definitions” chapters of Title 24, Parts 1 through 5 of the California Code of Regulations. Where terms, phrases, words and their derivatives are not defined in any of the references above, they shall be defined as specified in Webster’s Third New International Dictionary of the English Language, Unabridged (1961 edition, through the 2002 addenda), unless the context requires otherwise.
§ 1-4 High relevance — show source text
1.11 Office of the State Fire Marshal . . . . . . . . . . . . . . . . . . . 1-4

1.12 Board of Forestry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10

DIVISION II SCOPE AND ADMINISTRATION . . . . . . . . . . . . . 1-15

PART 1—GENERAL PROVISIONS. . . . . . . . . . . . . . . . . . . . . . . . . . 1-15

101 Scope and General Requirements. . . . . . . . . . . . . . 1-15

102 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-16

PART 2—ADMINISTRATION AND ENFORCEMENT . . . . . . . . . . . 1-17

103 Code Compliance Agency . . . . . . . . . . . . . . . . . . . . . 1-17

104 Duties and Powers of the Code Official . . . . . . . . . 1-17

105 Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-19

106 Construction Documents . . . . . . . . . . . . . . . . . . . . . 1-20

107 Temporary Uses, Equipment and Systems . . . . . . 1-21

108 Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-21

109 Inspection and Enforcement . . . . . . . . . . . . . . . . . . 1-22

110 Certificate of Completion . . . . . . . . . . . . . . . . . . . . . 1-24

111 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24

112 Means of Appeals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24

113 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25

CHAPTER 2 DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

201 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3

202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3

CHAPTER 3 WILDLAND-URBAN INTERFACE AREAS . . . . 3-3
§ 2-5 High relevance — show source text
Part II—Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5

CHAPTER 2 DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5

R201 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

R202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

Part III—Building Planning and Construction . . . . . . . . . . . .3-5

CHAPTER 3 BUILDING PLANNING . . . . . . . . . . . . . . . . . . . . .3-5

R300 Site Drainage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

R301 Design Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

R302 Fire-Resistant Construction . . . . . . . . . . . . . . . . . . . . 3-23

R303 Foam Plastic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-31

R304 Protection of Wood and Wood-Based Products

Against Decay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-33

R305 Protection Against Subterranean Termites. . . . . . . 3-35

R306 Flood-Resistant Construction. . . . . . . . . . . . . . . . . . . 3-36

R307 Storm Shelters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-40

R308 Site Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-40

R309 Automatic Sprinkler Systems . . . . . . . . . . . . . . . . . . . 3-41

R310 Smoke Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-54

R311 Carbon Monoxide Alarms. . . . . . . . . . . . . . . . . . . . . . . 3-58

R312 Minimum Room Areas . . . . . . . . . . . . . . . . . . . . . . . . . 3-59

R313 Ceiling Height . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-59
§ 1224.19.3.3.2.1 High relevance — show source text
1224.19.3.3.2.1 Reserved.

1224.19.3.3.2.2 Air quality. Hazardous buffer rooms shall be sealed tight and be under negative pressure relative to the anteroom. Air supply shall be laminar airflow with a low-level return. Refer to California Mechanical Code Table 4A, Title 16 Section 1751 and USP Chapter 800 for additional requirements.

1224.19.3.3.2.3 Finishes. The buffer room is considered a semirestricted area with nonporous and cleanable surfaces, ceil- ings, walls and floors subject to wet cleaning. The surfaces of ceilings, walls, floors, fixtures, shelving, work surfaces, counters and cabinets shall be smooth, seamless and impervious, free from cracks and crevices and be nonshedding. Ceil- ings shall be monolithic or utilize cleanroom style scrubbable panels, able to withstand cleaning with chemicals. If ceilings consist of inlaid panels, the panels must be caulked around each panel to seal them to the support frame. Juncture of ceil- ings to wall shall be coved or caulked to avoid cracks and crevices where dirt can accumulate. Sprinkler systems shall be recessed, covered, easily cleanable and of a type suitable for a cleanroom environment. Wall finishes shall be 2-coat epoxy covered gypsum board, seamless vinyl or other impervious covering. Work surfaces, shelving and cabinets shall be constructed of smooth, impervious materials, such as stainless steel or molded plastic so that they are easily cleaned and disinfected. Plastic laminate finish over a pervious substrate is not permitted.

1224.19.3.3.2.4 Eyewash station. If provided in the buffer room, the eyewash station shall be located just inside the door from the anteroom, a minimum clearance of 3.281 feet (1 meter) from the PEC, and must be dry, unless in use. Drains are not permitted in the buffer room.

1224.19.3.3.2.5 Refrigerator. Refrigerated storage may be provided in the negative pressure buffer room. Clearance around the refrigerator shall be accessible for cleaning.

1224.19.3.3.2.6 Doffing area. An area for doffing with a hamper shall be demarked inside the buffer/clean room at the door to the anteroom.

1224.19.3.3.2.7 Sealed tight room. Room perimeter walls, ceiling, floors, doors and penetrations shall be sealed tightly to minimize air infiltration from the outside or from other rooms. Buffer room doors shall be glass, metal or other phenolic material, self-closing and with hands-free door operation. Normal operation may include automatic door controls sequenc- ing such that only the buffer room door or the anteroom door is open at one time. Egress provisions shall not be impeded.

1224.19.3.3.2.8 Pass-throughs. If a pass-through is used between the buffer and anteroom, both doors should not be capable of being open at the same time, and the doors should be interlocking. A refrigerator pass-through shall not be used.
§ 7.62 High relevance — show source text
1. For occupancies in Groups R-2 and R-3, within the interior conditioned space of individual dwelling units, where the open-sided walking surface is located not more than 25 feet (7.62 meters) measured vertically to the floor or walking surface below, required guards shall not be less than 36 inches (914 mm) in height measured vertically above the adjacent walking surface. 3. For occupancies in Group R-3, and within individual dwelling units in occupancies in Group R-2, where the top of the guard serves as a handrail on the open sides of stairs, the top of the guard shall be not less than 34 inches (864 mm) and not more than 38 inches (965 mm) measured vertically from a line connecting the nosings. 4. The guard height in assembly seating areas shall comply with Section 1030.17 as applicable. 5. Along alternating tread devices and ship’s ladders, guards where the top rail serves as a handrail shall have height not less than 30 inches (762 mm) and not more than 34 inches (864 mm), measured vertically from a line connecting the leading edge of the treads. 6. In Group F occupancies where exit access stairways serve fewer than three stories and such stairways are not open to the public, and where the top of the guard also serves as a handrail, the top of the guard shall be not less than 34 inches (864 mm) and not more than 38 inches (965 mm) measured vertically from a line connecting the nosings.
[BE] 1015.4 Opening limitations. Required guards shall not have openings that allow passage of a sphere 4 inches (102 mm) in diameter from the walking surface to the required guard height.

Exceptions:
1. From a height of 36 inches (914 mm) to 42 inches (1067 mm), guards shall not have openings that allow passage of a sphere 4 [3] / 8 inches (111 mm) in diameter.
2. The triangular openings at the open sides of a stair, formed by the riser, tread and bottom rail shall not allow passage of a sphere 6 inches (152 mm) in diameter.
3. At elevated walking surfaces for access to and use of electrical, mechanical or plumbing systems or equipment, guards shall not have openings that allow passage of a sphere 21 inches (533 mm) in diameter.
4. In areas that are not open to the public within occupancies in Group I-3, F, H or S, and for alternating tread devices and ship’s ladders, guards shall not have openings that allow passage of a sphere 21 inches (533 mm) in diameter.
5. In assembly seating areas, guards required at the end of aisles in accordance with Section 1030.17.4 shall not have openings that allow passage of a sphere 4 inches (102 mm) in diameter up to a height of 26 inches (660 mm). From a height of 26 inches (660 mm) to 42 inches (1067 mm) above the adjacent walking surfaces, guards shall not have openings that allow passage of a sphere 8 inches (203 mm) in diameter.
6. Within individual dwelling units and sleeping units in Group R-2 and R-3 occupancies, guards on the open sides of stairs shall not have openings that allow passage of a sphere 4 [3] / 8 (111 mm) inches in diameter. 7. [SFM] In lifeguard towers not open to the public, guards shall not have openings which allow passage of a sphere 21 inches (533 mm) in diameter.
§ 1-18 Medium relevance — show source text
R104 Duties and Powers of the Building Official . . . . . . . 1-18

R105 Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-20

R106 Construction Documents . . . . . . . . . . . . . . . . . . . . . . 1-22

R107 Temporary Structures and Uses . . . . . . . . . . . . . . . . 1-23

R108 Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-23

R109 Inspections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-23

R110 Certificate of Occupancy. . . . . . . . . . . . . . . . . . . . . . . 1-25

R111 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25

R112 Means of Appeals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25

R113 Violations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-26

R114 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-26

Part II—Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5

CHAPTER 2 DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5

R201 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

R202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

Part III—Building Planning and Construction . . . . . . . . . . . .3-5

CHAPTER 3 BUILDING PLANNING . . . . . . . . . . . . . . . . . . . . .3-5

R300 Site Drainage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

R301 Design Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

R302 Fire-Resistant Construction . . . . . . . . . . . . . . . . . . . . 3-23

Frequently asked questions

Where do I look first for the meaning of a Part 6 term?

Look first in § 100.1; if it’s not defined there, the code directs you to the Definitions chapters of Title 24, Parts 1–5; if still undefined, use Webster’s Third per § 100.1.

If a Part 6 provision says “shall the installer provide X or Y,” how do I read that?

Per § 100.1(a).2, read the connective exactly: “and” requires all listed elements; “or” means one or more will suffice. If the text uses “shall” that part is mandatory.

Does “may” in Part 6 create a requirement?

No. “May” is permissive and does not create an obligation; “shall” is the mandatory term. § 100.1(a).3 makes this explicit.

If a term is defined differently in a referenced standard listed in § 100.1, which applies?

If § 100.1 names or incorporates a standard (for example an AAMA or ACCA document), the code text and the standard’s incorporated definition apply in the order indicated by § 100.1 and any incorporation language. Check § 100.1 for the specific referenced standard name and then that standard for its definitions.

The code doesn’t define a common word — can I use a dictionary?

Yes — if the word is not defined in § 100.1 or Title 24 Parts 1–5, the code directs you to Webster’s Third New International Dictionary unless context requires otherwise. § 100.1(b).

More in California Energy Code

Ask about the California Energy Code

Get cited, plain-English answers on the California Energy Code for your project — any code section, any scenario.

Start Free Trial

Related in the California Energy Code

If a term isn't defined in Section 100.1, where do I look next?

What are the formal rules of construction (mandatory vs permissive language)?

Definitions and rules of construction (how terms and language are interpreted)

California Energy Code