CMC · California Mechanical Code
Scope & Applicability
Chapter 1 of the CMC (notably §101.2 and §102.0–§102.3) defines what mechanical work the code covers and how conflicts, existing installations, and maintenance are handled.
Last reviewed: July 6, 2026
Overview
This part of the California Mechanical Code establishes what the code covers — the erection, installation, alteration, repair, relocation, replacement, addition to, use, and maintenance of mechanical systems in the adopting jurisdiction (see §101.2) . It also states the code’s purpose as a set of minimum requirements to protect public health, safety and welfare (see §101.3) .
The applicability rules explain how the CMC interacts with other codes and with existing work: conflicts between codes, treatment of existing installations, required maintenance, and rules for additions, alterations, and appendices are handled in Chapter 1 (see §102.0 et seq., including §102.1 and §102.2) . Knowing these sections is essential for deciding whether a project, an alteration, or an existing system must be brought into compliance and which code or provision controls.
In this section
Code references
Grounded in the retrieved California Mechanical Code — click a citation to read the verbatim passage:
CMC § 8.10 High relevance — show source text
1.8.10 Other Building Regulations . . . . . . . . . . . . . . . . . . . . . . 1-13
1.9 Division of the State Architect . . . . . . . . . . . . . . . . . . . . 1-13
1.10 Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15
1.11 Office of the State Fire Marshal . . . . . . . . . . . . . . . . . . . 1-17
1.12 State Librarian. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-22
1.13 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-22
1.14 California State Lands Commission . . . . . . . . . . . . . . . 1-22
DIVISION II – SCOPE AND ADMINISTRATION . . . . . . . . . . . . 1-23
Part 1—Scope and Application. . . . . . . . . . . . . . . . . . . . . . . . . . . 1-23
101 Scope and General Requirements. . . . . . . . . . . . . . . 1-23
102 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24
Part 2—Administration and Enforcement . . . . . . . . . . . . . . . . . 1-24
103 Code Compliance Agency . . . . . . . . . . . . . . . . . . . . . . 1-24
104 Duties and Powers of Building Official. . . . . . . . . . . 1-25
105 Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-27
106 Floor and Roof Design Loads . . . . . . . . . . . . . . . . . . . 1-29
107 Construction Documents . . . . . . . . . . . . . . . . . . . . . . 1-29
108 Temporary Structures, Equipment and Systems . . . . . . . . . . . . . . . . . . . . . 1-31
109 Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31
110 Inspections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31
111 Certificate of Occupancy. . . . . . . . . . . . . . . . . . . . . . . 1-33
CMC § 1-10 High relevance — show source text
1.11 Office of the State Fire Marshal . . . . . . . . . . . . . . . . . . . 1-10
1.12 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15
1.13 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15
1.14 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15
DIVISION II— SCOPE AND ADMINISTRATION . . . . . . . . . . . . . . . . . 1-17
Part 1—Scope and Application. . . . . . . . . . . . . . . . . . . . . . . . . . . 1-17
R101 Scope and General Requirements. . . . . . . . . . . . . . . 1-17
R102 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-17
Part 2—Administration and Enforcement . . . . . . . . . . . . . . . . . 1-18
R103 Code Compliance Agency . . . . . . . . . . . . . . . . . . . . . . 1-18
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
CMC § 101.2 Medium relevance — show source text
101.2 Scope . . . . . . . . . . . . . . . . . . . . . . . 21
101.3 Purpose . . . . . . . . . . . . . . . . . . . . . 21
101.4 Unconstitutional . . . . . . . . . . . . . . . 21
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TABLE OF CONTENTS
101.5 Validity . . . . . . . . . . . . . . . . . . . . . . 21
102.0 Applicability. . . . . . . . . . . . . . . . . . . 21
102.1 Conflicts Between Codes . . . . . . . . 21
102.2 Existing Installations . . . . . . . . . . . . 21
102.3 Maintenance . . . . . . . . . . . . . . . . . . 21
102.4 Additions, Alterations, Renovations, or Repairs . . . . . . . . . 21
102.5 Health and Safety . . . . . . . . . . . . . . 21
102.6 Changes in Building Occupancy. . . 21
102.7 Moved Structures . . . . . . . . . . . . . . 21
102.8 Appendices. . . . . . . . . . . . . . . . . . . 21
103.0 Duties and Powers of the
Authority Having Jurisdiction . . . . . 22
103.1 General. . . . . . . . . . . . . . . . . . . . . . 22
103.2 Liability . . . . . . . . . . . . . . . . . . . . . . 22
103.3 Applications and Permits . . . . . . . . 22
103.4 Right of Entry . . . . . . . . . . . . . . . . . 22
104.0 Permits . . . . . . . . . . . . . . . . . . . . . . 22
104.1 Permits Required . . . . . . . . . . . . . . 22
104.2 Exempt Work . . . . . . . . . . . . . . . . . 22
104.3 Application for Permit . . . . . . . . . . . 22
104.4 Permit Issuance . . . . . . . . . . . . . . . 23
104.5 Fees . . . . . . . . . . . . . . . . . . . . . . . . 24
105.0 Inspections and Testing . . . . . . . . . 24
105.1 General. . . . . . . . . . . . . . . . . . . . . . 24
105.2 Required Inspections . . . . . . . . . . . 24
105.3 Testing of Systems . . . . . . . . . . . . . 25
105.4 Connection to Service Utilities . . . . 25
106.0 Violations and Penalties . . . . . . . . . 25
106.1 General. . . . . . . . . . . . . . . . . . . . . . 25
CMC § 8.3 Medium relevance — show source text
1.8.3 Local Enforcing Agency . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
1.8.4 Permits, Fees, Applications and Inspections . . . . . . . . 1-7
1.8.5 Right of Entry for Enforcement. . . . . . . . . . . . . . . . . . . . . 1-8
1.8.6 Local Modification by Ordinance or Regulation . . . . . 1-8
1.8.7 Alternate Materials, Designs, Tests and Methods of Construction. . . . . . . . . . . . . . . 1-8
1.8.8 Appeals Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9
1.8.9 Unsafe Buildings or Structures . . . . . . . . . . . . . . . . . . . 1-10
1.8.10 Other Building Regulations . . . . . . . . . . . . . . . . . . . . . . 1-10
1.9 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10
1.10 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10
1.11 Office of the State Fire Marshal . . . . . . . . . . . . . . . . . . . 1-10
1.12 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15
1.13 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15
1.14 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15
DIVISION II— SCOPE AND ADMINISTRATION . . . . . . . . . . . . . . . . . 1-17
Part 1—Scope and Application. . . . . . . . . . . . . . . . . . . . . . . . . . . 1-17
R101 Scope and General Requirements. . . . . . . . . . . . . . . 1-17
R102 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-17
Part 2—Administration and Enforcement . . . . . . . . . . . . . . . . . 1-18
CMC § 11.4 Medium relevance — show source text
1.11.4 Fees . . . . . . . . . . . . . . . . . . . . . . . .18
1.11.5 Inspections . . . . . . . . . . . . . . . . . . .19
1.11.6 Certificate of Occupancy . . . . . . . .19
1.11.7 Temporary Structures and Uses . .19
1.11.8 Service Utilities . . . . . . . . . . . . . . . .19
1.11.9 Stop Work Order . . . . . . . . . . . . . .19
1.11.10 Unsafe Buildings, Structures, and Equipment . . . . . . . . . . . . . . . .19
1.11.11 Adopting Agency Identification . . .19
1.12.0 Reserved for the State Librarian . .19
1.13.0 Department of Water Resources (DWR) . . . . . . . . . . . . .19
1.13.1 Application . . . . . . . . . . . . . . . . . . .19
1.13.2 Adopting Agency Identification . . .19
1.14.0 Reserved for the State
Lands Commission . . . . . . . . . . . . .19
CHAPTER 1 DIVISION II
SCOPE AND ADMINISTRATION . .21
101.0 General . . . . . . . . . . . . . . . . . . . . . .21
101.1 Title . . . . . . . . . . . . . . . . . . . . . . . . .21
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TABLE OF CONTENTS
101.2 Scope . . . . . . . . . . . . . . . . . . . . . . .21
101.3 Purpose . . . . . . . . . . . . . . . . . . . . .21
101.4 Unconstitutional . . . . . . . . . . . . . . .21
101.5 Validity . . . . . . . . . . . . . . . . . . . . . .21
102.0 Applicability . . . . . . . . . . . . . . . . . . .21
102.1 Conflicts Between Codes . . . . . . . .21
102.2 Existing Installations . . . . . . . . . . . .21
102.3 Maintenance . . . . . . . . . . . . . . . . . .21
102.4 Additions, Alterations, Renovations, or Repairs . . . . . . . . .21
102.5 Health and Safety . . . . . . . . . . . . . .21
102.6 Changes in Building Occupancy . . .21
102.7 Moved Structures . . . . . . . . . . . . . .21
CMC § 90.1 Medium relevance — show source text
(2) Systems serving zones where specific humidity levels are required, such as museums and hospitals, and approved by the Authority Having Jurisdiction or required by accreditation standards, and where humidistatic controls are capable of and configured to maintain a dead band of at least 10 percent relative humidity where no active humidification or dehumidification takes place.
(3) Systems serving zones where humidity levels are required to be maintained with precision of not more than ±5 percent relative humidity to comply with applicable codes or accreditation standards or as approved by the Authority Having Jurisdiction.
[ASHRAE 90.1:6.4.3.6.1]
E 503.4.6.7.2 Humidification. Humidistatic controls shall not use fossil fuel or electricity to produce relative humidity above 30 percent in the warmest zone served by the system.
Exceptions:
(1) Systems serving zones where specific humidity levels are required, such as museums and hospitals, and approved by the Authority Having Jurisdiction or required by accreditation standards, and where humidistatic controls are capable of and configured to maintain a dead band of at least 10 percent relative humidity where no active humidification or dehumidification takes place.
TABLE E 503.4.6.4.2 MAXIMUM DAMPER LEAKAGE [1, 2]
(cubic foot per minute per square foot) at 1.0 inch water gauge
[ASHRAE 90.1: TABLE 6.4.3.4.3]
Col1 OUTDOOR AIR INTAKE (CFM/ft2) Col3 EXHAUST/RELIEF (CFM/ft2) Col5 CLIMATE ZONE NONMOTORIZED1 MOTORIZED NONMOTORIZED3 MOTORIZED 0, 1, 2 0, 1, 2 0, 1, 2 0, 1, 2 0, 1, 2 Any height 20 4 20 4 3 3 3 3 3 Any height 20 10 20 10 4, 5B, 5C 4, 5B, 5C 4, 5B, 5C 4, 5B, 5C 4, 5B, 5C Fewer than three stories 204 10 20 10 Three or more stories 204 10 204 10 5A, 6, 7, 8 5A, 6, 7, 8 5A, 6, 7, 8 5A, 6, 7, 8 5A, 6, 7, 8 Fewer than three stories 204 4 20 4 Three or more stories 204 4 204 4 CMC § 1.12.0 Medium relevance — show source text
1.12.0 Reserved for the State Librarian.
1.13.0 Reserved for the Department of Water Resources.
1.14.0 Reserved for the State Lands Commission.
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DIVISION II
SCOPE AND ADMINISTRATION
101.0 General.
101.1 Title. This document shall be known as the “Uniform Mechanical Code,” may be cited as such, and will be referred to herein as “this code.”
101.2 Scope. The provisions of this code shall apply to the erection, installation, alteration, repair, relocation, replacement, addition to, use, or maintenance of mechanical systems within this jurisdiction.
101.3 Purpose. This code is an ordinance providing minimum requirements and standards for the protection of the public health, safety, and welfare.
101.4 Unconstitutional. Where a section, subsection, sentence, clause, or phrase of this code is, for a reason, held to be unconstitutional, such decision shall not affect the validity of the remaining portions of this code. The legislative body hereby declares that it would have passed this code, and each section, subsection, sentence, clause, or phrase thereof, irrespective of the fact that one or more sections, subsections, sentences, clauses, and phrases are declared unconstitutional.
101.5 Validity. Where a provision of this code, or the application thereof to a person or circumstance, is held invalid, the remainder of the code, or the application of such provision to other persons or circumstances, shall not be affected thereby.
102.0 Applicability. 102.1 Conflicts Between Codes. Where the requirements within the jurisdiction of this mechanical code conflict with the requirements of the plumbing code, the plumbing code shall prevail. In instances where this code, applicable standards, or the manufacturer’s installation instructions conflict, the more stringent provisions shall prevail. Where there is a conflict between a general requirement and a specific requirement, the specific requirement shall prevail. [OSHPD 1, 1R, 2, 3, 4 & 5] See Chapter 1, Division I, Section 1.1.7
102.2 Existing Installations. Mechanical systems lawfully in existence at the time of the adoption of this code shall be permitted to have their use, maintenance, or repair continued where the use, maintenance, or repair is in accordance with the original design and location and no hazard to life, health, or property has been created by such mechanical system.
102.3 Maintenance. Mechanical systems, materials, and appurtenances, both existing and new, of a premise under the Authority Having Jurisdiction shall be maintained in operating condition. Devices or safeguards required by this code shall be maintained in accordance with the code edition under
which installed.
The owner or the owner’s designated agent shall be responsible for maintenance of mechanical systems. To determine compliance with this subsection, the Authority Having Jurisdiction shall be permitted to cause a mechanical system to be reinspected.
**102.3.1 Commercial HVAC Systems.
CMC § 11.4 Medium relevance — show source text
1.11.4 Fees . . . . . . . . . . . . . . . . . . . . . . . .18
1.11.5 Inspections . . . . . . . . . . . . . . . . . . .19
1.11.6 Certificate of Occupancy . . . . . . . .19
1.11.7 Temporary Structures and Uses . .19
1.11.8 Service Utilities . . . . . . . . . . . . . . . .19
1.11.9 Stop Work Order . . . . . . . . . . . . . .19
1.11.10 Unsafe Buildings, Structures,
and Equipment . . . . . . . . . . . . . . . .19
1.11.11 Adopting Agency Identification . . .19
1.12.0 Reserved for the State Librarian . .19
1.13.0 Reserved for the Department
of Water Resources . . . . . . . . . . . .19
1.14.0 Reserved for the State Lands
Commission . . . . . . . . . . . . . . . . . .19
CHAPTER 1 DIVISION II
SCOPE AND ADMINISTRATION. . .21
101.0 General. . . . . . . . . . . . . . . . . . . . . . 21
101.1 Title. . . . . . . . . . . . . . . . . . . . . . . . . 21
101.2 Scope . . . . . . . . . . . . . . . . . . . . . . . 21
101.3 Purpose . . . . . . . . . . . . . . . . . . . . . 21
101.4 Unconstitutional . . . . . . . . . . . . . . . 21
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TABLE OF CONTENTS
101.5 Validity . . . . . . . . . . . . . . . . . . . . . . 21
102.0 Applicability. . . . . . . . . . . . . . . . . . . 21
102.1 Conflicts Between Codes . . . . . . . . 21
102.2 Existing Installations . . . . . . . . . . . . 21
102.3 Maintenance . . . . . . . . . . . . . . . . . . 21
102.4 Additions, Alterations, Renovations, or Repairs . . . . . . . . . 21
102.5 Health and Safety . . . . . . . . . . . . . . 21
102.6 Changes in Building Occupancy. . . 21
102.7 Moved Structures . . . . . . . . . . . . . . 21
102.8 Appendices. . . . . . . . . . . . . . . . . . . 21
103.0 Duties and Powers of the
Authority Having Jurisdiction . . . . . 22
CMC § 608.0 Medium relevance — show source text
(3) Heating and cooling equipment in accordance with ACCA Manual S or other equivalent methods.
E 608.0 Low VOC Solvent Cement and Primer.
E 608.1 General. Primers and solvent cements used to join plastic pipe, and fittings shall be in accordance with Section E 608.1.1 and Section E 608.1.2.
E 608.1.1 Solvent Cement. Solvent cement, including one-step solvent cement, shall have a volatile organic compound (VOC) content of less than or equal to 65 ounces per gallon (oz/gal) (487 g/L) for CPVC cement, 68 oz/gal (509 g/L) for PVC cement, and 43 oz/gal (322 g/L) for ABS cement, as determined by the South Coast Air Quality Management District’s Laboratory Methods of Analysis for Enforcement Samples, Method 316A. E 608.1.2 Primer. Primer shall have a volatile organic compound (VOC) content of less than or equal to 73 oz/gal (546 g/L), as determined by the South Coast Air Quality Management District’s Laboratory Methods of Analysis for Enforcement Samples, Method 316A.
E 701.0 Installer Qualifications.
E 701.1 Scope. The provisions of this section address minimum qualifications of installers of mechanical systems covered within the scope of this appendix.
E 702.0 Qualifications.
E 702.1 General. Where permits are required, the Authority Having Jurisdiction shall have the authority to require contractors, installers, or service technicians to demonstrate competency. Where determined by the Authority Having Jurisdiction, the contractor, installer, or service technician shall be licensed to perform such work.
Part I
E 801.0 Heating, Ventilation, and Air Conditioning Systems Commissioning. E 801.1 Applicability. The provisions of this section apply to the commissioning of commercial and institutional HVAC systems.
E 802.0 Commissioning. E 802.1 Commissioning Requirements. HVAC commissioning shall be included in the design and construction processes of the project to verify that the HVAC systems and components meet the owner’s project requirements and in accordance with this appendix. Commissioning shall be performed in accordance with this appendix by personnel trained and certified in commissioning by a nationally recognized organization. Commissioning requirements shall include the following:
(1) Owner’s project requirements
(2) Basis of design
(3) Commissioning measures shown in the construction doc uments
(4) Commissioning plan
(5) Functional performance
(6) Testing
(7) Post construction documentation and training
(8) Commissioning report
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APPENDIX E
HVAC systems and components covered by this appendix as well as process equipment and controls, and renewable energy systems shall be included in the scope of the commissioning requirements. E 802.2 Owner’s Project Requirements (OPR). The performance goals and requirements of the HVAC system shall be documented before the design phase of the project begins. This documentation shall include not less than the following:
(1) Environmental and sustainability goals
(2) Energy efficiency goals
(3) Indoor environmental quality requirements
(4) Equipment and systems performance goals
CMC § 317.3 Medium relevance — show source text
317.3 Open Trenches. Excavations required to be made for the installation of a mechanical system or part thereof, within the walls of a building, shall be open trench work and shall be kept open until it has been inspected, tested, and accepted.
317.4 Excavations. Excavations shall be completely backfilled as soon after inspection as practicable. Precaution shall be taken to ensure compactness of backfill around piping without damage to such piping. Trenches shall be backfilled in thin layers to 12 inches (305 mm) above the top of the piping with clean earth, which shall not contain stones, boulders, cinderfill, frozen earth, construction debris, or other materials that will damage or break the piping or cause corrosive action. Mechanical devices such as bulldozers, graders, etc., shall be permitted to then be used to complete backfill to grade. Fill shall be properly compacted. Precautions shall be taken to ensure permanent stability for pipe laid in filled or made ground.
318.0 Scope. 318.1 Applicability. This part is applicable to health facil- ities regulated by OSHPD.
Note: This section has no corresponding provisions in the UMC. For the scope and authority of each state agency, refer to Chapter 1. 318.2 Services/Systems and Utilities. Refer to Section 1224.4.1, 1225.2.1 and 1228.4.1.1 of the California Building Code.
319.0 Steam and Hot-Water Systems. 319.1 Requirements for Hospitals and Optional Serv- ices Provided in Correctional Treatment Centers.
[OSHPD 1, 1R, 4 & 5]
319.1.1 Boilers shall have the capacity, based upon the rest ratings published by the Hydronics Institute or another acceptable national standard to supply the nor- mal operating requirements of all connected systems and equipment.
319.1.2 A minimum of two boilers shall be provided. The arrangement of boilers shall be based on the capacity and capability of a boiler or boilers to operate all sys- tems during-periods of breakdown or maintenance of any one boiler.
319.1.3 Boiler systems providing space heating shall be designed to maintain a minimum temperature of 60 ° F (15.6 ° C) in general patient areas and the temperatures specified in Table 4-A for sensitive areas during periods of breakdown or maintenance of any one boiler.
319.1.4 Boiler feed pumps, condensate return pumps, fuel oil pumps, and heating circulating pumps shall be connected and installed to provide standby service in the
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GENERAL REGULATIONS
CMC § 102.4 Medium relevance — show source text
ADMINISTRATION
DIVISION II SCOPE AND ADMINISTRATION
User notes:
About this chapter: Chapter 1 establishes the limits of applicability of the code and describes how the code is to be applied and enforced. Chapter 1 is in two parts: Part 1—Scope and Application (Sections 101–102) and Part 2—Administration and Enforcement (Sections 103–116). Section 101 identifies which buildings and structures come under its purview and references other ICodes as applicable. Standards and codes are scoped to the extent referenced (see Section 102.4).
This code is intended to be adopted as a legally enforceable document and it cannot be effective without adequate provisions for its administration and enforcement. 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 1 is largely concerned with maintaining “due process of law” in enforcing the building performance criteria contained in the body of the code.
ICC code development note: Code change proposals to this chapter will be considered by the Administrative Code Development Committee during the 2025 (Group B) Code Development Cycle.
Section 104 was revised for the 2024 edition. For complete information, see the Relocations table in the Preface of this code.
Note: Sections adopted or amended by state agencies are specifically indicated by an agency banner.
PART 1—SCOPE AND APPLICATION
SECTION 101—SCOPE AND GENERAL REQUIREMENTS
[A] 101.1 Title. These regulations shall be known as the Building Code of [ NAME OF JURISDICTION ], hereinafter referred to as “this code.”
[A] 101.2 Scope. The provisions of this code shall apply to the construction, alteration, relocation, enlargement, replacement, repair, equipment, use and occupancy, location, maintenance, removal and demolition of every building or structure or any appurtenances connected or attached to such buildings or structures.
Exception: Detached one- and two-family dwellings and townhouses not more than three stories above grade plane in height with a separate means of egress, and their accessory structures not more than three stories above grade plane in height, shall comply with this code or the California Residential Code .
[A] 101.2.1 Appendices. Provisions in the appendices shall not apply unless specifically adopted.
[A] 101.3 Purpose. The purpose of this code is to establish the minimum requirements to provide a reasonable level of safety, health and general welfare through structural strength, means of egress, stability, sanitation, light and ventilation, energy conservation, and for providing a reasonable level of life safety and property protection from the hazards of fire, explosion or dangerous conditions, and to provide a reasonable level of safety to firefighters and emergency responders during emergency operations.
[A] 101.4 Referenced codes. The other codes specified in Sections 101.4.1 through 101.4.7 and referenced elsewhere in this code shall be considered to be part of the requirements of this code to the prescribed extent of each such reference.
CMC § 1.11.11 Medium relevance — show source text
1.11.11 Adopting Agency Identification. The provisions of this code applicable to buildings identified in this Section 1.11 will be identi- fied in the Matrix Adoption Tables under the acronym SFM.
SECTION 1.12—STATE LIBRARIAN
1.12.1 Specific scope of application of the agency responsible for enforcement, the enforcement agency and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.
Application— Public library construction and renovation using funds from the California Library Construction and Renovation Bond Act of 1988.
Enforcing agency— State librarian.
Authority cited— Education Code Sections 19950 through 19981.
Reference— Education Code Sections 19950 through 19981.
SECTION 1.13—DEPARTMENT OF WATER RESOURCES
RESERVED
SECTION 1.14—CALIFORNIA STATE LANDS COMMISSION
1.14.1 Specific scope of application of the agency responsible for enforcement, the enforcement agency and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.
Application— Marine oil terminals.
Enforcing agency— California State Lands Commission.
Authority cited— Public Resources Code Section 8755.
Reference— Public Resources Code Section 8755.
1-22 2025 CALIFORNIA BUILDING CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
ADMINISTRATION
DIVISION II SCOPE AND ADMINISTRATION
User notes:
About this chapter: Chapter 1 establishes the limits of applicability of the code and describes how the code is to be applied and enforced. Chapter 1 is in two parts: Part 1—Scope and Application (Sections 101–102) and Part 2—Administration and Enforcement (Sections 103–116). Section 101 identifies which buildings and structures come under its purview and references other ICodes as applicable. Standards and codes are scoped to the extent referenced (see Section 102.4).
This code is intended to be adopted as a legally enforceable document and it cannot be effective without adequate provisions for its administration and enforcement. 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 1 is largely concerned with maintaining “due process of law” in enforcing the building performance criteria contained in the body of the code.
ICC code development note: Code change proposals to this chapter will be considered by the Administrative Code Development Committee during the 2025 (Group B) Code Development Cycle.
Section 104 was revised for the 2024 edition. For complete information, see the Relocations table in the Preface of this code.
Note: Sections adopted or amended by state agencies are specifically indicated by an agency banner.
PART 1—SCOPE AND APPLICATION
SECTION 101—SCOPE AND GENERAL REQUIREMENTS
[A] 101.1 Title. These regulations shall be known as the Building Code of [ NAME OF JURISDICTION ], hereinafter referred to as “this code.”
Frequently asked questions
What exactly does §101.2 cover — new work only or existing systems too?
§101.2 describes the code’s scope to include not only new erection and installation but also alteration, repair, relocation, replacement, addition to, use, and maintenance of mechanical systems; existing lawful systems may remain provided they do not create a hazard (see §101.2 and §102.2) .
If the mechanical code conflicts with the plumbing code, which one applies?
Where requirements of the Mechanical Code conflict with the Plumbing Code, the Plumbing Code prevails; more generally, the more stringent requirement applies when there is a conflict among this code, referenced standards, or manufacturer instructions (see §102.1) .
Do the appendices automatically apply?
Appendix provisions are not mandatory unless specifically adopted by the jurisdiction; Chapter 1 describes how appendices are treated in applicability and adoption (see §102.8 and related notes in Chapter 1) .
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