Chapter 3 — GENERAL REGULATIONS
313.4 Alignment.
California Plumbing Code (Title 24, Part 5) · 2025 edition · updated 2026-09-10 · California
Italicized text is a California amendment to the model code, as printed in the official publication.
Piping shall be supported in such a manner as to maintain its alignment and prevent sagging.
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Ask AI about this code▸Contents — California Plumbing Code (Title 24, Part 5)
California Plumbing Code (Title 24, Part 5)
- Chapter 1 — GENERAL CODE PROVISIONS
- Chapter 2 — DEFINITIONS
▸Chapter 3 — GENERAL REGULATIONS
Overview- 301.1 Applicability. This chapter shall govern the general
- 301.2 Minimum Standards. Pipe, pipe fittings, traps, fixtures,…
- 301.3 Alternate Materials and Methods of Construction
- 301.4 Flood Hazard Areas. Plumbing systems shall be
- 301.5 Alternative Engineered Design. An alternative
- 301.6 Tall Wood (Mass Timber) Buildings. Plumbing
- 301.7 One- and Two-Family Dwellings. [HCD 1] The
- 301.8 OSHPD 1R. [OSHPD 1R] For OSHPD 1R, refer to
- 302.1 General. Iron, steel, copper, and copper alloy pipe
- 303.1 General. It shall be unlawful for a person to cause,
- 304.1 General. Plumbing fixtures, drains, appurtenances,
- 305.1 Unlawful Practices. It shall be unlawful for a person to…
- 306.1 Detrimental Wastes. Wastes detrimental to the public sew…
- 306.2 Safe Discharge. Sewage or other waste from a
- 307.1 System. Except as otherwise provided in this code,
- 307.2 Ownership. No subdivision, sale, or transfer of ownershi…
- 308.1 General. Piping, fixtures, appliances, or equipment
- 309.1 Engineering Practices. Design, construction, and
- 309.2 Concealing Imperfections. It is unlawful to conceal
- 309.3 Burred Ends. Burred ends of pipe and tubing shall
- 309.4 Installation Practices. Plumbing systems shall be
- 309.5 Sound Transmission. Plumbing piping systems
- 309.6 Dead Legs. Dead legs shall have a method of flushing.
- 310.1 Fittings. No double hub fitting, single or double tee
- 310.2 Drainage and Vent Piping. No drainage or vent
- 310.3 Waste Connection. No waste connection shall be
- 310.4 Use of Vent and Waste Pipes. Except as hereinafter provi…
- 310.5 Obstruction of Flow. No fitting, fixture and piping
- 310.6 Dissimilar Metals. Except for necessary valves,
- 310.7 Direction of Flow. Valves, pipes, and fittings shall
- 310.8 Screwed Fittings. Screwed fittings shall be ABS,
- 310.9 Female Plastic Connections. Female plastic
- 310.10 ABS and PVC Transition Joints. Except as provided in Se…
- 310.11 [OSHPD 1, 2, 3, 4 & 5] Drainage piping over oper-
- 310.12 [OSHPD 1, 3, 4 & 5] Floor drains, waste traps, san-
- 310.13 [SFM] For applications listed in Section 1.11.0 regu-
- 310.14 Services/Systems and Utilities. [OSHPD 1, 2, 4
- 310.15 Telephone and Data Equipment Rooms.
- 311.1 General. The drainage system of each new building
- 312.1 General. Piping passing under or through walls shall
- 312.2 Installation. Piping in connection with a plumbing
- 312.3 Building Sewer and Drainage Piping. No building sewer or…
- 312.4 Corrosion, Erosion, and Mechanical Damage.
- 312.5 Protectively Coated Pipe. Protectively coated pipe
- 312.6 Freezing Protection. No water, soil, or waste pipe
- 312.7 Fire-Resistant Construction. Piping penetrations
- 312.8 Waterproofing of Openings. Joints at the roof
- 312.9 Steel Nail Plates. Plastic piping or tubing, and copper …
- 312.10 Sleeves. Sleeves shall be provided to protect piping th…
- 312.11 Structural Members. A structural member weakened or imp…
- 312.12 Rodentproofing. Strainer plates on drain inlets
- 313.1 General. Piping, tubing, fixtures, appliances, and
- 313.2 Material. Hangers, supports, and anchors shall be of
- 313.3 Suspended Piping. Suspended piping shall be supported at…
- 313.4 Alignment. Piping shall be supported in such a manner as…
- 313.5 Underground Installation. Piping in the ground
- 313.6 Hanger Rod Sizes. Hanger rod sizes shall be not
- 313.7 Gas Piping. Gas piping shall be supported by metal
- 313.8 [OSHPD 1, 2, 3, 4 & 5] Refer to Title 24, Part 2 of the
- 314.1 Trenches. Trenches deeper than the footing of a
- 314.2 Tunneling and Driving. Tunneling and driving shall
- 314.3 Open Trenches. Excavations required to be made
- 314.4 Excavations. Excavations shall be completely backfilled …
- 315.1 Unions. Approved unions shall be permitted to be
- 315.2 Prohibited Joints and Connections. A fitting or
- 316.1 General. Where different sizes of pipes and fittings
- 317.1 General. Food or drink shall not be stored, prepared,
- 318.1 General. Tests in accordance with this code, which
- 318.2 Pressure Tests (10 psi or less). Required pressure tests…
- 318.3 Pressure Tests (greater than 10 psi to 100 psi).
- 318.4 Pressure Tests (exceeding 100 psi). Required
- 318.5 Pressure Range. Test gauges shall have a pressure
- 319.1 General. Such piping shall be in accordance with the
- 320.1 General. Where pressure piping systems are rehabilitated…
- 323.0 Plumbing Equipment Schedules. [OSHPD 1, 2,
- Chapter 4 — PLUMBING FIXTURES AND FIXTURE FITTINGS
- Chapter 5 — WATER HEATERS
- Chapter 6 — WATER SUPPLY AND DISTRIBUTION
- Chapter 7 — SANITARY DRAINAGE
- Chapter 8 — INDIRECT WASTES
- Chapter 9 — VENTS
- Chapter 10 — TRAPS AND INTERCEPTORS
- Chapter 11 — STORM DRAINAGE
- Chapter 12 — FUEL GAS PIPING
- Chapter 13 — HEALTH CARE FACILITIES AND MEDICAL GAS AND MEDICA…
- Chapter 14 — FIRESTOP PROTECTION
- Chapter 15 — ALTERNATE WATER SOURCES FOR NONPOTABLE APPLICATIONS
- Chapter 16 — NONPOTABLE RAINWATER CATCHMENT SYSTEMS
- Chapter 17 — REFERENCED STANDARDS
- Appendix A — RECOMMENDED RULES FOR SIZING THE WATER SUPPLY SYS…
- Appendix B — EXPLANATORY NOTES ON COMBINATION WASTE AND VENT S…
- Appendix C — ALTERNATE PLUMBING SYSTEMS
- Appendix D — SIZING STORM WATER DRAINAGE SYSTEMS
- Appendix E — MANUFACTURED/MOBILE HOME PARKS AND RECREATIONAL V…
- Appendix F — FIREFIGHTER BREATHING AIR REPLENISHMENT SYSTEMS
- Appendix G — SIZING OF VENTING SYSTEMS
- Appendix H — PRIVATE SEWAGE DISPOSAL SYSTEMS
- Appendix I — INSTALLATION STANDARDS
- Appendix J — COMBINATION OF INDOOR AND OUTDOOR COMBUSTION AND …
- Appendix K — POTABLE RAINWATER CATCHMENT SYSTEMS
- Appendix L — SUSTAINABLE PRACTICES
- Appendix M — PEAK WATER DEMAND CALCULATOR
- Appendix N — IMPACT OF WATER TEMPERATURE ON THE POTENTIAL FOR …
- Appendix O — NON-SEWERED SANITATION SYSTEMS
- Appendix P — PROFESSIONAL QUALIFICATIONS
- Appendix Q — INDOOR HORTICULTURAL FACILITIES
- Appendix R — TINY HOUSES
- Appendix S — ONSITE STORMWATER TREATMENT SYSTEMS