CEBC · California Existing Building Code

What are the repair rules for mechanical and plumbing systems?

If your building needs mechanical or plumbing repairs, the CEBC requires that repairs not leave the building less-compliant than it was before the damage. Mechanical repairs must follow the California Mechanical Code and plumbing repairs must follow the California Plumbing Code; replaced toilets must be ≤ 1.28 gpf and medical-gas repairs in health-care occupancies must follow NFPA 99.

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Last reviewed: July 6, 2026

What the code requires — plain English

Repairs to mechanical systems must not make the building less complying than it was before the damage and must comply with the California Mechanical Code. See § 407.1.
Plumbing repairs must not use materials or methods that are prohibited by the California Plumbing Code, and repaired plumbing must comply with the California Plumbing Code (and applicable CALGreen divisions). See § 408.1.

The single most important rule: repairs must restore systems without making the building less complying than it was before the damage. § 407.1 clarifies this requirement for mechanical repairs.

Requirements in detail

General repair principle

Do not reduce compliance: A repair cannot leave the building in a less-compliant condition than it was before the damage. This general principle is stated for mechanical repairs in § 407.1 and is the basic test the code uses to decide whether work is simply a repair or an alteration that triggers more stringent requirements. § 407.1.

Mechanical repairs (what you must do)

If you are repairing a mechanical system, the repaired components and the repair work must comply with the California Mechanical Code (i.e., follow the rules that apply to installation, alteration, repair and replacement in that code). See § 407.1.
Repairs must not create unsafe, overloaded, or insanitary conditions; if the repair would, the Mechanical Code requirements for new systems apply. See § 407.1.

Plumbing repairs (materials & special rules)

Materials. Plumbing materials and supplies may not be used for repairs when their use is prohibited by the California Plumbing Code. See § 408.1.
Energy / water-efficiency for replacement fixtures. When replacing water closets, the maximum allowable flush volume is 1.28 gallons (4.8 L) per flush cycle. See § 408.2.
Health-care medical gas repairs. Portions of medical gas systems being repaired in Group I-2 (health care), ambulatory care facilities and outpatient clinics must comply with NFPA 99 for repairs. See § 408.3.

Decision matrix (quick reference)

Decision factor	What the code requires	When it applies	Code Reference
Repair must maintain prior compliance	Repair cannot make building less complying than before damage	All mechanical repairs	§ 407.1
Applicable mechanical standard	Use California Mechanical Code for repairs	All mechanical repairs	§ 407.1
Use of plumbing materials	Do not use materials for repairs that are prohibited by the California Plumbing Code	All plumbing repairs	§ 408.1
Water closet replacements	Maximum 1.28 gallons (4.8 L) per flushing cycle	When replacing water closets	§ 408.2
Medical gas repairs in health care	Repairs must comply with NFPA 99	Repairs to medical gas systems in Group I-2, ambulatory care and outpatient clinics	§ 408.3

Exceptions & special cases

The CEBC text for these sections does not list a set of explicit numerical exemptions beyond the water-closet maximum and the health-care NFPA 99 requirement. For plumbing materials prohibited by the California Plumbing Code, the CEBC simply defers to the Plumbing Code — consult the Plumbing Code for any specific material prohibitions. See § 408.1.
For mechanical repairs, the CEBC requires compliance with the California Mechanical Code but does not itself prescribe alternate thresholds or special exceptions in § 407.1; special-case rules (such as those for state agencies or hospital occupancies) appear elsewhere in the code adoption tables and agency-specific chapters. See § 407.1 and the CEBC adoption/matrix material. file

Common mistakes

Assuming any replacement part or material is acceptable for a repair — but plumbing repairs must not use materials prohibited by the California Plumbing Code (§ 408.1).
Replacing water closets with higher-flow models; replacement toilets must meet 1.28 gpf maximum per § 408.2.
Treating a major repair as a simple repair: if the work would reduce compliance or make the system unsafe, the more stringent Mechanical or Plumbing Code requirements for new work may apply (see § 407.1 and § 408.1).
Ignoring health-care-specific codes: repairing medical gas systems in Group I-2 occupancies requires NFPA 99 compliance per § 408.3.

Worked example

Scenario: A building owner discovers corrosion leaks and must replace three water closets in a public restroom.

The owner intends to replace each old 3.5 gpf toilet with new fixtures. Under § 408.2, the maximum allowable flush volume for all replaced water closets is 1.28 gallons (4.8 L) per flush cycle, so 3.5 gpf fixtures are not allowed for replacement. Action: select toilets rated ≤ 1.28 gpf. § 408.2.
If the repairs require replacing drain piping with materials that the California Plumbing Code prohibits for the building’s application, those materials cannot be used — confirm acceptable materials in the California Plumbing Code before ordering. § 408.1.
The repairs must not result in the restroom or building being less complying than prior to the damage. If replacing the fixtures or piping would create a condition that is less compliant (for example, reduce required clearances or egress paths), further work to restore compliance will be required. § 407.1 (general repair compliance principle).

Related provisions

§ 401.2 — General compliance rule: work shall not make the building less complying than it was before the repair.
§ 1101.2 — Creation or extension of nonconformity (additions/alterations shall not create/extend nonconformities).
California Mechanical Code (referenced by CEBC): see the local adoption and mechanical-code requirements (CEBC defers mechanics to the California Mechanical Code per § 407.1). file
California Plumbing Code (referenced by CEBC): plumbing repairs and prohibited materials are governed by the California Plumbing Code per § 408.1. file

Code references

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

CEBC § 101.4 High relevance — show source text
[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.

[A] 101.4.1 Gas. The provisions of the California Plumbing Code and/or the California Mechanical Code shall apply to the installation of gas piping from the point of delivery, gas appliances and related accessories as covered in this code. These requirements apply to gas piping systems extending from the point of delivery to the inlet connections of appliances and the installation and operation of residential and commercial gas appliances and related accessories.

[A] 101.4.2 Mechanical. The provisions of the California Mechanical Code shall apply to the installation, alterations, repairs and replacement of mechanical systems, including equipment, appliances, fixtures, fittings and appurtenances, including ventilating, heating, cooling, air-conditioning and refrigeration systems, incinerators and other energy-related systems.

[A] 101.4.3 Plumbing. The provisions of the California Plumbing Code shall apply to the installation, alteration, repair and replacement of plumbing systems, including equipment, appliances, fixtures, fittings and appurtenances, and where connected to a water or sewage system and all aspects of a medical gas system. The provisions of the California Plumbing Code shall apply to private sewage disposal systems.

[A] 101.4.4 Property maintenance. The provisions of the California Existing Building Code shall apply to existing structures and premises; equipment and facilities; light, ventilation, space heating, sanitation, life and fire safety hazards; responsibilities of owners, operators and occupants; and occupancy of existing premises and structures.

[A] 101.4.5 Fire prevention. The provisions of the California Fire Code shall apply to matters affecting or relating to structures, processes and premises from the hazard of fire and explosion arising from the storage, handling or use of structures, materials or devices; from conditions hazardous to life, property or public welfare in the occupancy of structures or premises; and from the construction, extension, repair, alteration or removal of fire suppression, automatic sprinkler systems and alarm systems or fire hazards in the structure or on the premises from occupancy or operation.

[A] 101.4.6 Energy. The provisions of the California Energy Code shall apply to all matters governing the design and construction of buildings for energy efficiency.

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ADMINISTRATION

[A] 101.4.7 Existing buildings. The provisions of the California Existing Building Code shall apply to matters governing the repair, alteration, change of occupancy, addition to and relocation of existing buildings.

[OSHPD 1] The provisions of Chapters 2, 3A, 4A and 5A of the California Existing Building Code shall apply to all matters governing the repairs, alterations, change of occupancy, additions and relocation of existing structures and portions thereof under OSHPD jurisdic- tion. All references to Chapters 3, 4 and 5 of the California Existing Building Code shall be replaced by equivalent provisions in Chapters 3A, 4A and 5A.

CEBC § 407.1 High relevance — show source text

SECTION 407—MECHANICAL

407.1 General. Existing mechanical systems undergoing repair shall not make the building less complying than it was before the damaged occurred. [HCD 1, HCD 2 & BSC] Existing mechanical systems undergoing repair shall comply with the California Mechanical Code.

SECTION 408—PLUMBING

408.1 Materials. Plumbing materials and supplies shall not be used for repairs that are prohibited in the California Plumbing Code .

[HCD 1, HCD 2, BSC & BSC-CG] Existing plumbing systems undergoing repair shall comply with the California Plumbing Code and Divi- sion 4.3 or Division 5.3 of the CALGreen Code, as applicable.

408.2 Water closet replacement. The maximum water consumption flow rates and quantities for all replaced water closets shall be 1.28 gallons (4.8 L ) per flushing cycle.

408.3 Health care facilities. Portions of medical gas systems being repaired in Group I-2, ambulatory care facilities and outpatient clinics shall comply with NFPA 99 requirements for repairs.

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CALIFORNIA EXISTING BUILDING CODE – MATRIX ADOPTION TABLE

CHAPTER 4A – REPAIRS [OSHPD 1]

(Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

Adopting Agency	BSC	BSC- CG	SFM	HCD	Col6	Col7	DSA	Col9	Col10	OSHPD	Col12	Col13	Col14	Col15	Col16	Col17	BSCC	DPH	AGR	DWR	CEC	CA	SL	SLC
Adopting Agency	BSC	BSC- CG	SFM	1	2	1/AC	AC	SS	SS/CC	1	1R	2	3	4	5	6	6	6	6	6	6	6	6	6
Adopt Entire Chapter										X
Adopt Entire Chapter as amended (amended sections listed below)
Adopt only those sections that are listed below
Chapter / Section

The state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.

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CEBC § 405.2.6 High relevance — show source text
[BS] 405.2.6 Flood hazard areas. In flood hazard areas, buildings that have sustained substantial damage shall be brought into compliance with Section 1612 of the California Building Code or Section R306 of the California Residential Code, as applicable.

SECTION 406—ELECTRICAL

[OSHPD 1R, 2, 4 & 5] Not adopted by OSHPD. Existing electrical wiring and equipment undergoing repair shall be in accordance with Title 24 Part 3 California Electrical Code (CEC).

406.1 General. Repairs to existing electrical wiring and equipment shall be in accordance with the California Electrical Code.

406.1.1 Reconditioned electrical equipment. Reconditioned electrical equipment shall comply with the California Electrical Code . Electrical equipment prohibited from being reconditioned by the applicable sections of the California Electrical Code shall not be reconditioned unless permitted by NFPA 99.

406.1.2 Health care facilities. Portions of electrical systems being repaired in Group I-2, ambulatory care facilities and outpatient clinics shall comply with NFPA 99 requirements for repairs.

SECTION 407—MECHANICAL

407.1 General. Existing mechanical systems undergoing repair shall not make the building less complying than it was before the damaged occurred. [HCD 1, HCD 2 & BSC] Existing mechanical systems undergoing repair shall comply with the California Mechanical Code.

SECTION 408—PLUMBING

408.1 Materials. Plumbing materials and supplies shall not be used for repairs that are prohibited in the California Plumbing Code .

[HCD 1, HCD 2, BSC & BSC-CG] Existing plumbing systems undergoing repair shall comply with the California Plumbing Code and Divi- sion 4.3 or Division 5.3 of the CALGreen Code, as applicable.

408.2 Water closet replacement. The maximum water consumption flow rates and quantities for all replaced water closets shall be 1.28 gallons (4.8 L ) per flushing cycle.

408.3 Health care facilities. Portions of medical gas systems being repaired in Group I-2, ambulatory care facilities and outpatient clinics shall comply with NFPA 99 requirements for repairs.

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CALIFORNIA EXISTING BUILDING CODE – MATRIX ADOPTION TABLE

CHAPTER 4A – REPAIRS [OSHPD 1]

(Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
CEBC § 3A-9 High relevance — show source text
305A In-Situ Load Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3A-9

306A Accessibility for Existing Buildings . . . . . . . . . . . . . . . .3A-9

307A Smoke Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3A-9

308A Carbon Monoxide Detection . . . . . . . . . . . . . . . . . . . . . .3A-9

309A Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3A-10

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CONTENTS

310A Compliance Alternatives for Services/Systems and Utilities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3A-10

311A Compliance Alternatives for Means of Egress. . . . . 3A-11

312A Removal of Hospital SPC and Freestanding Buildings from General Acute Care Service. . . 3A-12

313A Earthquake Monitoring Instruments for Existing Buildings . . . . . . . . . . . . . . . . . . . . . . 3A-14

CHAPTER 4 REPAIRS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

401 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

402 Building Elements and Materials . . . . . . . . . . . . . . . . . 4-3

403 Fire Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

404 Means of Egress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

405 Structural . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

406 Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4

407 Mechanical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4

408 Plumbing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
CEBC § 12.7 High relevance — show source text
Columns shall consist of rolled or built-up wide_ flange sections or noncomposite built-up box or HSS with a minimum wall thickness of [3] / 4 inch (19 mm), or satisfy the requirements of width-to-thickness ratios of highly ductile members in AISC 341. 2. The biaxial dual-strong axis and column minor axis configurations of the moment connection shall be considered as an alternative system. 3. For SMF and IMF systems, on the sideplate standard or configuration A the U-shaped cover plates shall be used with the k dimension extension. The k dimension extension length is defined as beam depth d b /6, rounded to the nearest [1] / 2 inch (12.7 mm).

4. The hinge-to-hinge span to beam depth, L h /d, shall be greater than or equal to 4.5. 5. The width-to-thickness ratios for beam flanges shall not be less than 3.5. Exception: For width-to-thickness ratios less than 3.5 the C pr shall be calculated in accordance with that for welded side- plate connections but in no case shall the width-to-thickness ratio be less than 3.0. 6. The minimum bolt-to-bolt spacing shall not be less than 3 bolt diameters. 7. The extension of the side plates beyond the face of the column shall be within the range of 0.65d to 1.5d. 8. The gap-to-side plate thickness ratio shall range from 2.1 to 2.3.

Exception: The gap-to-side plate thickness ratio shall be permitted to be modified for moment connections with unequal beam sizes on opposite sides of the column or when orthogonal beams acting as drag connections frame into the side plate. 9. Demand Critical fillet welds {2}, {5}, {5a} and {8} shall have Magnetic Particle Testing (MT) in accordance with AWS D1.1 for procedure, technique and acceptance. Inspect the beginning and end of these welds for a 6-inch (152 mm) length, plus any location along the length of the weld where a start and restart is visually noted for a distance of 6 inches (152 mm) on either side of the start/stop location. 10. The connection specific factor to account for peak connection strength, C pr , shall be between 1.15 and 1.35. Calculations shall be submitted to OSHPD for review and approval. 11. For in-plane collectors transferring axial loads into the sideplate connection, coordination between sideplate and the regis- tered design professional in responsible charge will be required to confirm the collector connection is sufficient to transfer _the load into the moment frame system.
CEBC § 2.5 High relevance — show source text
405 A .2.5 Substantial structural damage to snow load-carrying components. Where substantial structural damage to any snow load-carrying components is caused by or related to snow load effects, any components required to carry snow loads on roof framing of similar construction shall be repaired, replaced or retrofitted to satisfy the requirements of Section 1608 of the California Building Code .

405 A .2.6 Flood hazard areas. In flood hazard areas, buildings that have sustained substantial damage shall be brought into compliance with Section 1612 A of the California Building Code .

SECTION 406 A —ELECTRICAL

406 A .1 General. Existing electrical wiring and equipment undergoing repair shall be in accordance with Title 24 Part 3 California Electri- cal Code (CEC).

406 A .1.1 Reconditioned electrical equipment. Reconditioned electrical equipment shall comply with the California Electrical Code . Electrical equipment prohibited from being reconditioned by the applicable sections of the California Electrical Code shall not be reconditioned unless permitted by NFPA 99.

406 A .1.2 Health care facilities. Portions of electrical systems being repaired in Group I-2, ambulatory care facilities and outpatient clinics shall comply with NFPA 99 requirements for repairs.

SECTION 407 A —MECHANICAL

407 A .1 General. Existing mechanical systems undergoing repair shall not make the building less complying than it was before the damaged occurred.

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REPAIRS

SECTION 408 A —PLUMBING

408 A .1 Materials. Plumbing materials and supplies shall not be used for repairs that are prohibited in the Title 24 Part 5 California Plumbing Code (CPC).

408 A .2 Water closet replacement. The maximum water consumption flow rates and quantities for all replaced water closets shall be 1.28 gallons ( 4.8 L) per flushing cycle.

408 A .3 Health care facilities. Portions of medical gas systems being repaired in Group I-2, ambulatory care facilities and outpatient clinics shall comply with NFPA 99 requirements for repairs.

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CALIFORNIA EXISTING BUILDING CODE – MATRIX ADOPTION TABLE

CHAPTER 5 – PRESCRIPTIVE COMPLIANCE METHOD

(Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
CEBC § 25218.5 High relevance — show source text
(d) Alternate method of compliance. Any addition, alteration or repair may comply with the requirements of Title 24, Part 6 by meeting the applicable requirements for the entire building.

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, 25910, and 25943, Public Resources Code .

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NONRESIDENTIAL AND HOTEL/MOTEL OCCUPANCIES— ADDITIONS, ALTERATIONS AND REPAIRS

SECTION 141.1—REQUIREMENTS FOR COVERED PROCESSES IN ADDITIONS, ALTERATIONS TO EXISTING NONRESIDENTIAL AND HOTEL/MOTEL BUILDINGS

Covered processes in additions or alterations to existing buildings that will be nonresidential and hotel/motel occupancies shall comply with the applicable Subsections of Section 120.6 and 140.9.

(a) Lab and Process Facility Exhaust Systems. Additions and alterations to existing laboratories and factories shall meet the requirements of Section 140.9(c).

(b) Computer Rooms. All newly installed computer room cooling systems and uninterruptible power supply systems in additions/alterations shall meet the requirements of Sections 120.6(j), 140.9(a)2 and 140.9(a)4 and comply with Item 1 below.
1. Economizers. Each individual cooling system primarily serving computer rooms in an existing building shall include either: A. An integrated air economizer capable of partial cooling when additional mechanical cooling is required and capable of providing 100 percent of the expected system cooling load up to 80°F room supply air temperature at outside air temperatures of 55°F dry-bulb and below or 50°F wet-bulb and below, and be equipped with a fault detection and diagnostic system as specified by Section 120.2(i); or B. An integrated water economizer capable of partial cooling when additional mechanical cooling is required and capable of providing 100 percent of the expected system cooling load up to 80°F room supply air temperature at outside air temperatures of 40°F dry-bulb and below or 35°F wet-bulb and below. Exception 1 to Section 141.1(b)1: Individual computer rooms with an ITE design load under 5 tons (18 kW) in a building that does not have any economizers. Exception 2 to Section 141.1(b)1: New cooling systems serving an existing computer room in an existing building with an ITE design load up to a total of 50 tons (176 kW). Exception 3 to Section 141.1(b)1: New cooling systems serving a new computer room in an existing building with an ITE design load up to a total of 20 tons (70 kW).
(c) Controlled Environment Horticulture Spaces.
1. Indoor growing, space-conditioning systems and dehumidification. All newly installed heating, ventilation, air conditioning systems or dehumidification systems in buildings with indoor growing shall meet the applicable requirements of Sections 120.6(h)1 and 120.6(h)2.
CEBC § 1101.2 High relevance — show source text
1101.2 Creation or extension of nonconformity. An addition shall not create or extend any nonconformity in the existing building to which the addition is being made with regard to accessibility, structural strength, supports and attachments for nonstructural components, fire safety, means of egress or the capacity of mechanical, plumbing or electrical systems.

Exception: Nonconforming supports and attachments for nonstructural components that serve the addition from within the existing building need not be altered to comply with California Building Code Section 1613 unless the components are part of the addition’s life safety system or are required to serve an addition assigned to Risk Category IV.

[BS] 1101.3 Risk category assignment. Where the addition and the existing building have different occupancies, the risk category of each existing and added occupancy shall be determined in accordance with Section 1604.5.1 of the California Building Code . Where application of that section results in a higher risk category for the existing building compared with the risk category for the existing building before the addition, such a change shall be considered a change of occupancy and shall comply with Chapter 10 of this code. Where application of that section results in a higher risk category for the addition compared with the risk category for the addition by itself, the addition and any systems in the existing building required to serve the addition shall comply with the requirements of the California Building Code for new construction for the higher risk category.

1101.4 Other work. Any repair or alteration work within an existing building to which an addition is being made shall comply with the applicable requirements for the work as classified in Chapter 6.

1101.5 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.

1101.6 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.

1101.7 Occupiable roofs. Where a new occupiable roof is added to a building or structure, the occupiable roof shall comply with the provisions of the California Building Code .

SECTION 1102—HEIGHTS AND AREAS

1102.1 Height limitations. An addition shall not increase the height of an existing building beyond that permitted under the applicable provisions of Chapter 5 of the California Building Code for new buildings.

1102.2 Area limitations. An addition shall not increase the area of an existing building beyond that permitted under the applicable provisions of Chapter 5 of the California Building Code for new buildings unless fire separation as required by the California Building Code is provided.

1102.3 Fire protection systems. Existing fire areas increased by the addition shall comply with Chapter 9 of the California Building Code .
CEBC § 405.2.4 Medium relevance — show source text
[BS] 405.2.4 Substantial structural damage to gravity load-carrying components. Gravity load-carrying components that have sustained substantial structural damage shall be retrofitted to comply with the applicable provisions for dead, live and snow loads in the California Building Code . Undamaged gravity load-carrying components, including undamaged foundation components, that receive dead, live or snow loads from retrofitted components shall also be retrofitted if required to comply with these design loads.

[BS] 405.2.4.1 Lateral force-resisting elements. Regardless of the level of damage to vertical elements of the lateral forceresisting system, if substantial structural damage to gravity load-carrying components was caused primarily by wind or seismic effects, then the building shall be evaluated in accordance with Section 405.2.3.1 and, if noncompliant, retrofitted in accordance with Section 405.2.3.3.

Exceptions:
1. Buildings assigned to Seismic Design Category A, B or C whose substantial structural damage was not caused by earthquake need not be evaluated or retrofitted for load combinations that include earthquake effects.
2. One- and two-family dwellings need not be evaluated or retrofitted for load combinations that include earthquake effects.
[BS] 405.2.5 Substantial structural damage to snow load-carrying components. Where substantial structural damage to any snow load-carrying components is caused by or related to snow load effects, any components required to carry snow loads on roof framing of similar construction shall be repaired, replaced or retrofitted to satisfy the requirements of Section 1608 of the California Building Code .

[BS] 405.2.6 Flood hazard areas. In flood hazard areas, buildings that have sustained substantial damage shall be brought into compliance with Section 1612 of the California Building Code or Section R306 of the California Residential Code, as applicable.

SECTION 406—ELECTRICAL

[OSHPD 1R, 2, 4 & 5] Not adopted by OSHPD. Existing electrical wiring and equipment undergoing repair shall be in accordance with Title 24 Part 3 California Electrical Code (CEC).

406.1 General. Repairs to existing electrical wiring and equipment shall be in accordance with the California Electrical Code.

406.1.1 Reconditioned electrical equipment. Reconditioned electrical equipment shall comply with the California Electrical Code . Electrical equipment prohibited from being reconditioned by the applicable sections of the California Electrical Code shall not be reconditioned unless permitted by NFPA 99.

406.1.2 Health care facilities. Portions of electrical systems being repaired in Group I-2, ambulatory care facilities and outpatient clinics shall comply with NFPA 99 requirements for repairs.

SECTION 407—MECHANICAL

407.1 General. Existing mechanical systems undergoing repair shall not make the building less complying than it was before the damaged occurred. [HCD 1, HCD 2 & BSC] Existing mechanical systems undergoing repair shall comply with the California Mechanical Code.

SECTION 408—PLUMBING

408.1 Materials. Plumbing materials and supplies shall not be used for repairs that are prohibited in the California Plumbing Code .
CEBC § 101.5 Medium relevance — show source text
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. Commercial HVAC systems both existing and new, and parts thereof shall be inspected and maintained in operating condition in accordance with ASHRAE/ACCA 180. The owner or the owner’s designated agent shall be responsible for maintenance of mechanical systems and equipment. To determine compliance with this subsection, the Authority Having Jurisdiction shall be permitted to cause a HVAC system to be reinspected. 102.3.2 Residential HVAC Systems. Residential HVAC systems both existing and new, and parts thereof shall be inspected in accordance with ACCA 4 QM. The owner or the owner’s designated agent shall be responsible for maintenance of mechanical systems and equipment. To determine compliance with this subsection, the Authority Having Jurisdiction shall be permitted to cause a HVAC system to be reinspected.

102.4 Additions, Alterations, Renovations, or Repairs. Additions, alterations, renovations, or repairs shall conform to that required for a new system without requiring the existing mechanical system to be in accordance with the requirements of this code. Additions, alterations, renovations, or repairs shall not cause an existing system to become unsafe, insanitary or overloaded.

Additions, alterations, renovations, or repairs to existing mechanical system installations shall comply with the provisions for new construction, unless such deviations are found to be necessary and are first approved by the Authority Having Jurisdiction. 102.5 Health and Safety. Where compliance with the provisions of this code fails to eliminate or alleviate a nuisance, or other dangerous or insanitary condition that involves health or safety hazards, the owner or the owner’s agent shall install such additional mechanical system facilities or shall make such repairs or alterations as ordered by the Authority Having Jurisdiction. **102.6 Changes in Building Occupancy.
CEBC § 4-3 Medium relevance — show source text
CHAPTER 4 REPAIRS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

401 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

402 Building Elements and Materials . . . . . . . . . . . . . . . . . 4-3

403 Fire Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

404 Means of Egress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

405 Structural . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

406 Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4

407 Mechanical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4

408 Plumbing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4

CHAPTER 4A [OSHPD 1] REPAIRS . . . . . . . . . . . . . . . . . . . . .4A-3

401A General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-3

402A Building Elements and Materials. . . . . . . . . . . . . . . . . .4A-3

403A Fire Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-3

404A Means of Egress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-3

405A Structural. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-3

406A Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-4

407A Mechanical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-4
CEBC § 501A.3.3.3 Medium relevance — show source text
501A.3.3.3 For NPC 3 and NPC 4 or NPC 4D in SPC 2, SPC 3, SPC 4 or SPC-4D buildings, the adequacy and design of nonstructural component or equipment supports and attachments may extend only to the connection of the component or equipment to the support when the total reaction at the point of support (including the application of F p ) is less than or equal to the following limits: 1. 250 pounds for components or equipment attached to light frame walls. For the purposes of this requirement, the sum of the absolute value of all reactions due to component loads on a single stud shall not exceed 250 pounds. 2. 1,000 pounds for components or equipment attached to roofs or walls of reinforced concrete or masonry construction. 3. 2,000 pounds for components or equipment attached to floors or slabs-on-grade.

Exception: If the anchorage or bracing is configured in a manner that results in significant torsion on a supporting structural element, the effects of the nonstructural reaction force on the structural element shall be considered in the anchorage design.

501 A . 4 Health care facilities. In Group I-2 facilities, ambulatory care facilities and outpatient clinics, any altered or added portion of an existing electrical or medical gas systems shall be required to meet installation and equipment requirements in NFPA 99.

SECTION 502 A —ADDITIONS

502 A .1 General. Additions to any building or structure shall comply with the requirements of the California Building Code for new construction. Alterations to the existing building or structure shall be made to ensure that the existing building or structure together with the addition are not less complying with the provisions of the California Building Code than the existing building or structure was prior to the addition. An existing building together with its additions shall comply with the height and area provisions of Chapter 5 of the California Building Code . Where a new occupiable roof is added to a building or structure, the occupiable roof shall comply with the provisions of the California Building Code.

Exception: In-filling of floor openings and nonoccupiable appendages such as elevator and exit stairway shafts shall be permitted beyond that permitted by the California Building Code.

502 A .1.1 Risk category assignment. Where the addition and the existing building have different occupancies, the risk category of each existing and added occupancy shall be determined in accordance with Section 1604 A .5.1 of the California Building Code . Where application of that section results in a higher risk category for the existing building compared with the risk category for the existing building before the addition, such a change shall be considered a change of occupancy and shall comply with Section 506 A of this code. Where application of that section results in a higher risk category for the addition compared with the risk category for the addition by itself, the addition and any systems in the existing building required to serve the addition shall comply with the requirements of the California Building Code for new construction for the higher risk category.

502 A .1.2 Creation or extension of nonconformity. An addition shall not create or extend any nonconformity in the existing building to which the addition is being made with regard to accessibility, structural strength, supports and attachments for nonstructural components, fire safety, means of egress or the capacity of mechanical, plumbing or electrical systems.

Frequently asked questions

Do repairs always have to meet the Mechanical/Plumbing Code for new construction?

No — the CEBC frames repairs so they do not make the building less complying than before the damage and directs repairs to comply with the California Mechanical Code or California Plumbing Code where applicable. If a repair would create an unsafe or noncompliant condition, the more stringent new-construction requirements may apply. See § 407.1 and § 408.1.

Can I install any toilet I want when replacing an old one?

No. Replaced water closets must have a maximum flush volume of 1.28 gallons (4.8 L) per flush cycle under § 408.2.

What about repairs to medical gas systems in a hospital?

Repairs to portions of medical gas systems in Group I-2, ambulatory care facilities and outpatient clinics must comply with NFPA 99 for repairs, per § 408.3.

If a part is discontinued, can I use a different material for the repair?

Only if the replacement material is not prohibited by the California Plumbing Code (for plumbing) and the repair does not cause reduced compliance. The CEBC defers to the referenced code for acceptable materials — see § 408.1.

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Related in the CEBC

How must repairs maintain the building's level of fire protection?

What governs electrical repairs under Chapter 4?

Do repairs have to preserve the existing level of means-of-egress protection?

Means of egress, fire protection, electrical, mechanical and plumbing

California Existing Building Code