CPC · California Plumbing Code

Fixture installation, securing, and supply/drain connections

This hub summarizes CPC requirements for setting, supporting, and connecting plumbing fixtures (mounting, flanges, supply fittings, accessibility, and coordination with Chapters 6–7).

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Last reviewed: July 6, 2026

Overview

This area of the California Plumbing Code (CPC) covers how plumbing fixtures are set, supported, secured, and connected to water supply and sanitary drainage so they function safely, remain accessible for service, and protect potable water and the drainage system. Key requirements address fixture mounting and joints, flanged connections and closet flanges, supply fittings and backflow protection, and accessibility for concealed connections and future installations. See, for example, the installation and securing provisions at §402.0–§402.11 and the specific flanged-connection and closet-flange rules in §402.6.

Proper supply and drain connections are coordinated with the CPC’s water-supply and sanitary-drainage chapters so that backflow prevention, pipe materials, sizing, and venting are not compromised by how fixtures are mounted or connected. Chapter 6 (Water Supply) and Chapter 7 (Sanitary Drainage) provide the related material, sizing, and backflow requirements that apply to fixture connections.

Because many requirements are installation- and product-specific, the CPC also requires compliance with manufacturer installation instructions and makes concealed connections accessible for inspection and repair (for example, §402.8–§402.10). These rules help preserve trap seals, permit repair without destructive demolition, and maintain required backflow protection.

In this section

Code references

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

CPC § 402.6.2 High relevance — show source text
Closet rings (closet flanges) shall be adequately designed and secured to support fixtures connected thereto.

402.6.2 Securing Closet Flanges. Closet screws, bolts, washers, and similar fasteners shall be of copper alloy, copper, or other listed equally corrosion-resistant materials. Screws and bolts shall be of a size and number to properly support the fixture installed. 402.6.3 Securing Floor-Mounted, Back-Outlet Water Closet Bowls. Floor-mounted, back-outlet water closet bowls shall be set level with an angle of 90 degrees (1.57 rad) between the floor and wall at the centerline of the fixture outlet. The floor and wall shall have a flat mounting surface not less than 5 inches (127 mm) to the right and left of the fixture outlet centerline. The closet flange shall be secured to the wall mounting surface. Offset, eccentric, or reducing closet flanges shall not be permitted with these fixtures.

The fixture shall be secured to the wall outlet flange or drainage connection and the floor by corrosion-resistant screws or bolts.

402.7 Supply Fittings. The supply lines and fittings for every plumbing fixture shall be so installed as to prevent backflow in accordance with Chapter 6.

402.8 Installation. Fixtures shall be installed in accordance

with the manufacturer’s installation instructions.

402.9 Design and Installation of Plumbing Fixtures. Plumbing fixtures shall be installed in accordance with the manufacturer’s installation instructions. The means of backflow prevention shall not be compromised by the designated fixture fitting mounting surface. 402.10 Slip Joint Connections. Fixtures having concealed slip joint connections shall be provided with an access panel or utility space not less than 12 inches (305 mm) in its least dimension and so arranged without obstructions as to make such connections accessible for inspection and repair. 402.11 Future Fixtures. Where provisions are made for the future installation of fixtures, those provided for shall be considered in determining the required sizes of the drain and water supply piping. Construction for future installations shall be terminated with a plugged fitting or fittings. Where the plugged

fitting is at the point where the trap of a fixture is installed, the plumbing system for such fixture shall be complete and be in accordance with the plumbing requirements of this code.

403.0 Accessible Plumbing Facilities. 403.1 General. Where accessible facilities are required in applicable building regulations, the facilities shall be installed in accordance with those regulations. [HCD 1-AC] For spe- cific requirements regarding accommodations for persons with disabilities, see Chapter 11A of the California Building Code. 403.2 Fixtures and Fixture Fittings for Persons with Disabilities. Plumbing fixtures and fixture fittings for persons with disabilities shall be in accordance with ICC A117.1 and the applicable standards referenced in Chapter 4. [HCD 1-AC] Specific requirements regarding accommodations for persons with disabilities are contained in Chapter 11A of the California Building Code. 403.3 Exposed Pipes and Surfaces. Water supply and drainpipes under accessible lavatories and sinks shall be insulated or otherwise be configured to protect against contact. Protectors, insulators, or both shall comply with ASME A112.18.9 or ASTM C1822.
CPC § 401.2 High relevance — show source text
401.2 Quality of Fixtures . . . . . . . . . . . . .59

401.3 Water-Conserving Fixtures and Fittings . . . . . . . . . . . . . . . . . . .59

402.0 Installation . . . . . . . . . . . . . . . . . . .59

402.1 Cleaning . . . . . . . . . . . . . . . . . . . . .59

402.2 Joints . . . . . . . . . . . . . . . . . . . . . . .59

402.3 Securing Fixtures . . . . . . . . . . . . . .59

402.4 Wall-Hung Fixtures . . . . . . . . . . . . .59

402.5 Setting . . . . . . . . . . . . . . . . . . . . . .59

402.6 Flanged Fixture Connections . . . . .59

402.7 Supply Fittings . . . . . . . . . . . . . . . .60

402.8 Installation . . . . . . . . . . . . . . . . . . .60

402.9 Design and Installation of Plumbing Fixtures . . . . . . . . . . . . . .60

402.10 Slip Joint Connections . . . . . . . . . .60

402.11 Future Fixtures . . . . . . . . . . . . . . . .60

403.0 Accessible Plumbing Facilities . . . .60

403.1 General . . . . . . . . . . . . . . . . . . . . . .60

403.2 Fixtures and Fixture Fittings for Persons with Disabilities . . . . . .60

403.3 Exposed Pipes and Surfaces . . . . .60

404.0 Waste Fittings and Overflows . . . . .60

404.1 Waste Fittings . . . . . . . . . . . . . . . . .60

404.2 Overflows . . . . . . . . . . . . . . . . . . . .60

405.0 Prohibited Fixtures . . . . . . . . . . . . .60

405.1 Prohibited Water Closets . . . . . . . .60

405.2 Prohibited Urinals . . . . . . . . . . . . . .60

405.3 Miscellaneous Fixtures . . . . . . . . . .60

406.0 Special Fixtures and Specialties . . .61

406.1 Water and Waste Connections . . . .61

406.2 Special Use Sinks . . . . . . . . . . . . .61

406.3 Special Use Fixtures . . . . . . . . . . .61

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TABLE OF CONTENTS

406.4 Zinc Alloy Components . . . . . . . . .61

407.0 Lavatories . . . . . . . . . . . . . . . . . . . .61

407.1 Application . . . . . . . . . . . . . . . . . . .61

407.2 Water Consumption . . . . . . . . . . . .61

407.3 Limitation of Hot Water
CPC § 1101.1 High relevance — show source text
Plumbing fixture replacement is required_ prior to issuance of a certificate of final completion, certificate of occupancy, or final permit approval by the local building department. See Civil Code Section 1101.1, et seq., for the def- inition of a noncompliant plumbing fixture, types of residential buildings affected and other important enactment dates. Note 3: [OSHPD 1, 2, 3 & 4] Also refer to Title 20, Cali- fornia Code of Regulations, Division 2, Chapter 4, Article 4, Section 1605.3 (i). Note 4: Appliance Efficiency Regulations – Water Effi- ciency. [CEC] Where California law in Title 20 Sections 1601 et seq. applying to water-using appliances sold or offered for sale within the state specifies a lower maximum flow rate than specified in Section 407.2, 408.3, or 411.2, the lower maximum flow rate shall be required.

402.0 Installation.

402.1 Cleaning. Plumbing fixtures shall be installed in a manner to afford easy access for repairs and cleaning. Pipes from fixtures shall be run to the nearest wall.

402.2 Joints. Where a fixture comes in contact with the wall or floor, the joint between the fixture and the wall or floor shall be made watertight.

402.3 Securing Fixtures. Floor-outlet or floor-mounted fixtures shall be rigidly secured to the drainage connection and to the floor, where so designed, by screws or bolts of copper, copper alloy, or other equally corrosion-resistant material.

402.4 Wall-Hung Fixtures. Wall-hung fixtures shall be rigidly supported by metal supporting members so that no strain is transmitted to the connections. Floor-affixed supports for off-the-floor plumbing fixtures for public use shall comply with ASME A112.6.1M. Framing-affixed supports for off-thefloor water closets with concealed tanks shall comply with ASME A112.6.2. Flush tanks and similar appurtenances shall be secured by approved non-corrosive screws or bolts.

402.5 Setting. Fixtures shall be set level and in proper alignment with reference to adjacent walls. No water closet or bidet shall be set closer than 15 inches (381 mm) from its center to a side wall or obstruction or closer than 30 inches (762 mm) center to center to a similar fixture. The clear space in front of a water closet, lavatory, or bidet shall be not less than 24 inches (610 mm). No urinal shall be set closer than 12 inches (305 mm) from its center to a side wall or partition or closer than 24 inches (610 mm) center to center.

Exception: The installation of paper dispensers or accessibility grab bars shall not be considered obstructions.

402.6 Flanged Fixture Connections. Fixture connections between drainage pipes and water closets, floor outlet service sinks and urinals shall be made using an approved copper alloy, hard lead, ABS, PVC, or iron flanges caulked, soldered, solvent cemented; rubber compression gaskets; or screwed to the drainage pipe. The connection shall be bolted with an approved gasket, washer, or setting compound between the fixture and the connection. The bottom of the flange shall be set on the top of the finished floor.
CPC § 402.10 High relevance — show source text
402.10 Slip Joint Connections. Fixtures having concealed slip joint connections shall be provided with an access panel or utility space not less than 12 inches (305 mm) in its least dimension and so arranged without obstructions as to make such connections accessible for inspection and repair. 402.11 Future Fixtures. Where provisions are made for the future installation of fixtures, those provided for shall be considered in determining the required sizes of the drain and water supply piping. Construction for future installations shall be terminated with a plugged fitting or fittings. Where the plugged

fitting is at the point where the trap of a fixture is installed, the plumbing system for such fixture shall be complete and be in accordance with the plumbing requirements of this code.

403.0 Accessible Plumbing Facilities. 403.1 General. Where accessible facilities are required in applicable building regulations, the facilities shall be installed in accordance with those regulations. [HCD 1-AC] For spe- cific requirements regarding accommodations for persons with disabilities, see Chapter 11A of the California Building Code. 403.2 Fixtures and Fixture Fittings for Persons with Disabilities. Plumbing fixtures and fixture fittings for persons with disabilities shall be in accordance with ICC A117.1 and the applicable standards referenced in Chapter 4. [HCD 1-AC] Specific requirements regarding accommodations for persons with disabilities are contained in Chapter 11A of the California Building Code. 403.3 Exposed Pipes and Surfaces. Water supply and drainpipes under accessible lavatories and sinks shall be insulated or otherwise be configured to protect against contact. Protectors, insulators, or both shall comply with ASME A112.18.9 or ASTM C1822. [HCD 1-AC] Specific requirements regard- ing accommodations for persons with disabilities are contained in Chapter 11A of the California Building Code.

404.0 Waste Fittings and Overflows. 404.1 Waste Fittings. Waste fittings shall comply with ASME A112.18.2/CSA B125.2, ASTM F409 or Table 701.2 for aboveground drainage piping and fittings. 404.2 Overflows. Where a fixture is provided with an overflow, the overflow shall comply with Section 404.2.1 or Section 404.2.2.

404.2.1 Sinks, Lavatories, and Bathtubs. The waste shall be so arranged that the standing water in the fixture shall not rise in the overflow where the stopper is closed or remain in the overflow where the fixture is empty. The overflow pipe from a fixture shall be connected to the house or inlet side of the fixture trap.

404.2.2 Water Closets and Urinals. Overflows on flush tanks shall be permitted to discharge into the water closets or urinals served by them.

405.0 Prohibited Fixtures.

405.1 Prohibited Water Closets. Water closets having an invisible seal or an unventilated space or having walls which are not thoroughly washed at each discharge shall be prohibited. A water closet that might permit siphonage of the contents of the bowl back into the tank shall be prohibited. 405.2 Prohibited Urinals. Trough urinals and urinals with an invisible seal shall be prohibited.
CPC § 908.2.4 High relevance — show source text
908.2.4 Water Closet. The water closet fixture drain or trap arm connection to the wet vent shall be downstream of fixture drain or trap arm connections to the horizontal wet vent.

908.2.5 Additional Fixtures. Additional fixtures shall discharge downstream of the wet vent system and be conventionally vented. Only the fixtures within the bathroom group shall connect to the wet-vented horizontal branch.

909.0 Special Venting for Island Fixtures. 909.1 General. Traps for island sinks and similar equipment shall be roughed in above the floor and shall be permitted to be vented by extending the vent as high as possible, but not less than the drainboard height and then returning it downward and connecting it to the horizontal sink drain immediately downstream from the vertical fixture drain. The return vent shall be connected to the horizontal drain through a wyebranch fitting and shall, in addition, be provided with a foot vent taken off the vertical fixture vent by means of a wye branch immediately below the floor and extending to the nearest partition and then through the roof to the open air, or shall be permitted to be connected to other vents at a point not less than 6 inches (152 mm) above the flood-level rim of the fixtures served. Drainage fittings shall be used on the vent below the floor level, and a slope of not less than [1] ⁄ 4 inch per foot (20.8 mm/m) back to the drain shall be maintained. The return bend used under the drainboard shall be a one-piece

fitting or an assembly of a 45 degree (0.79 rad), a 90 degree (1.57 rad), and a 45 degree (0.79 rad) elbow in the order named. Pipe sizing shall be as elsewhere required in this code. The island sink drain, upstream of the returned vent, shall serve no other fixtures. An accessible cleanout shall be installed in the vertical portion of the foot vent.

910.0 Combination Waste and Vent Systems. 910.1 Where Permitted. Combination waste and vent systems shall be permitted where structural conditions preclude the installation of conventional systems as otherwise prescribed by this code. 910.2 Approval. Construction documents for each combination waste and vent system shall first be approved by the Authority Having Jurisdiction before a portion of such system is installed.

910.3 Vents. Each combination waste and vent system, as defined in Chapter 2, shall be provided with a vent or vents adequate to ensure free circulation of air. A branch exceeding 15 feet (4572 mm) in length shall be separately vented in an approved manner. The area of a vent installed in a combination waste and vent system shall be not less than one-half the inside cross-sectional area of the drainpipe served. The vent connection shall be downstream of the uppermost fixture. 910.4 Connections and Size. Branches serving traps shall connect to the main line at an angle not exceeding 2 percent. Each waste pipe and each trap in such a system shall be not less than two pipe sizes exceeding the sizes required by Chapter 7 of this code, and not less than two pipe sizes exceeding a fixture tailpiece or connection. 910.5 Vertical Waste Pipe. No vertical waste pipe shall be used in such a system, except the tailpiece or connection between the outlet of a plumbing fixture and the trap. Such tailpieces or connections shall be as short as possible, and in no case shall exceed 2 feet (610 mm).
CPC § 318.1 High relevance — show source text
318.1 General . . . . . . . . . . . . . . . . . . . . . .54

318.2 Pressure Tests (10 psi or less) . . .54

318.3 Pressure Tests (greater than 10 psi to 100 psi) . . . . . . . . . . . . . .54

318.4 Pressure Tests (exceeding 100 psi) . . . . . . . . . . . . . . . . . . . . . .54

318.5 Pressure Range . . . . . . . . . . . . . . .54

319.0 Medical Gas and Vacuum

Systems . . . . . . . . . . . . . . . . . . . . .54

319.1 General . . . . . . . . . . . . . . . . . . . . . .54

320.0 Rehabilitation of Piping Systems . .54

320.1 General . . . . . . . . . . . . . . . . . . . . . .54

321.0 Essential Plumbing Provisions . . . .54

322.0 Psychiatric Services . . . . . . . . . . . .54

323.0 Plumbing Equipment Schedules . . .55

Table 313.3 Hangers and Supports . . . . . . . . . .55

CHAPTER 4 PLUMBING FIXTURES

AND FIXTURE FITTINGS . . . . . . .57

401.0 General . . . . . . . . . . . . . . . . . . . . . .59

401.1 Applicability . . . . . . . . . . . . . . . . . . .59

401.2 Quality of Fixtures . . . . . . . . . . . . .59

401.3 Water-Conserving Fixtures and Fittings . . . . . . . . . . . . . . . . . . .59

402.0 Installation . . . . . . . . . . . . . . . . . . .59

402.1 Cleaning . . . . . . . . . . . . . . . . . . . . .59

402.2 Joints . . . . . . . . . . . . . . . . . . . . . . .59

402.3 Securing Fixtures . . . . . . . . . . . . . .59

402.4 Wall-Hung Fixtures . . . . . . . . . . . . .59

402.5 Setting . . . . . . . . . . . . . . . . . . . . . .59

402.6 Flanged Fixture Connections . . . . .59

402.7 Supply Fittings . . . . . . . . . . . . . . . .60

402.8 Installation . . . . . . . . . . . . . . . . . . .60

402.9 Design and Installation of Plumbing Fixtures . . . . . . . . . . . . . .60

402.10 Slip Joint Connections . . . . . . . . . .60

402.11 Future Fixtures . . . . . . . . . . . . . . . .60

403.0 Accessible Plumbing Facilities . . . .60

403.1 General . . . . . . . . . . . . . . . . . . . . . .60
CPC § 402.6.1 Medium relevance — show source text
Wall-mounted water closet fixtures shall be securely bolted to an approved carrier fitting. The approved carrier fitting shall be securely attached to the structure. The connecting pipe between the carrier fitting and the fixture shall be an approved material and designed to accommodate an adequately sized gasket. Gasket material shall be neoprene, felt, or similar approved types.

402.6.1 Closet Rings (Closet Flanges). Closet rings (closet flanges) for water closets or similar fixtures shall be of an approved type and shall be copper alloy, copper, hard lead, cast-iron, galvanized malleable iron,

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PLUMBING FIXTURES AND FIXTURE FITTINGS

ABS, PVC, or other approved materials. Closet rings (closet flanges) shall be approximately 7 inches (178 mm) in diameter and, where installed, shall, together with the soil pipe, present a 1 [1] ⁄ 2 inch (38 mm) wide flange or face to receive the fixture gasket or closet seal.

Caulked-on closet rings (closet flanges) shall be not less than [1] ⁄ 4 of an inch (6.4 mm) thick and not less than 2 inches (51 mm) in overall depth.

Closet rings (closet flanges) shall be burned or soldered to lead bends or stubs, shall be caulked to cast-iron soil pipe, shall be solvent cemented to ABS and PVC, and shall be screwed or fastened in an approved manner to other materials.

Closet bends or stubs shall be cut-off to present a smooth surface even with the top of the closet ring before the rough inspection is called.

Closet rings (closet flanges) shall be adequately designed and secured to support fixtures connected thereto.

402.6.2 Securing Closet Flanges. Closet screws, bolts, washers, and similar fasteners shall be of copper alloy, copper, or other listed equally corrosion-resistant materials. Screws and bolts shall be of a size and number to properly support the fixture installed. 402.6.3 Securing Floor-Mounted, Back-Outlet Water Closet Bowls. Floor-mounted, back-outlet water closet bowls shall be set level with an angle of 90 degrees (1.57 rad) between the floor and wall at the centerline of the fixture outlet. The floor and wall shall have a flat mounting surface not less than 5 inches (127 mm) to the right and left of the fixture outlet centerline. The closet flange shall be secured to the wall mounting surface. Offset, eccentric, or reducing closet flanges shall not be permitted with these fixtures.

The fixture shall be secured to the wall outlet flange or drainage connection and the floor by corrosion-resistant screws or bolts.

402.7 Supply Fittings. The supply lines and fittings for every plumbing fixture shall be so installed as to prevent backflow in accordance with Chapter 6.

402.8 Installation. Fixtures shall be installed in accordance

with the manufacturer’s installation instructions.

402.9 Design and Installation of Plumbing Fixtures. Plumbing fixtures shall be installed in accordance with the manufacturer’s installation instructions. The means of backflow prevention shall not be compromised by the designated fixture fitting mounting surface. **402.10 Slip Joint Connections.
CPC § 2025 Medium relevance — show source text
An acceptable air supply for combustion and ventilation is necessary for the proper operation of fuel-burning appliances. A shortage of combustion air can result in incomplete combustion and the production of poisonous gases, such as carbon monoxide or appliance overheating. Ventilation air provides cooling for the appliance casing and internal controls. Inadequate ventilation of the space in which an appliance is installed can result in increased surrounding temperatures that stress the appliance itself or other appliances in the vicinity.

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FORMAT OF THE UNIFORM PLUMBING CODE

Chapter 6 Water Supply and Distribution.

Chapter 6 regulates the design, material, and installation of water supply and distribution systems, including residential fire sprinklers. The water supply and distribution system is designed to achieve the correct water pressure and flow rates and avoid cross-connections. For fixtures to perform properly, an acceptable supply of potable water is essential to their operation and use. Cross-connections and backflow are ranked as the highest priority because of the long history of recognized health risks posed by cross-connections, outbreaks, or cases of waterborne disease. Piping materials and components are evaluated for their possible effect on the potable water with which they are in contact. The intent is to control the potential adverse health effects produced by indirect additives, products, and materials that come in contact with potable water. When selecting materials for water supply and distribution systems, consider water pressure, water temperature, compatibility with the water supply, durability, support, and sustainability.

In addition, this chapter regulates the design, location, materials, and installation of multipurpose and stand-alone sprinkler systems that do not include the use of antifreeze. Where systems are installed as a portion of the water distribution system under the requirements of this chapter and are not provided with a fire department connection, backflow protection for the water supply system is not required.

Chapter 7 Sanitary Drainage.

This chapter regulates the design and installation of sanitary drainage systems to ensure they will work as intended. Drainage piping should not be oversized nor undersized, and constructed of approved materials to guard against fouling, deposit of solids, clogging, and with cleanouts so arranged that the pipes may be readily cleaned. The purpose of the sanitary drainage system is to remove effluent discharged from plumbing fixtures and other equipment to an approved point of disposal, such as a public sanitary system or private sewage disposal system.

The basics of a sanitary drainage system include public and private sewage disposal; selection of materials; installation of the building drain and sewer; joining methods for pipe and fittings; drainage fixture units for sizing the drainage system; sumps and ejectors; vent sizing and length of vents; and testing.

Chapter 8 Indirect Wastes.

Chapter 8 regulates indirect waste connections that are required for plumbing fixtures and plumbing appliances dealing with food preparation, dishwashing, potable liquids, and similar equipment. An indirect connection prevents sewage from backing up into a fixture or appliance, thus providing protection against potential health hazards. The waste pipe discharges through an air gap or air break into a waste receptor or standpipe. The protection in the form of an air gap is necessary when the contamination is a potential health hazard or cross connection with the potable water system. Where there is no possibility of contaminating the potable water (nonpotable discharge), the indirect waste pipe may connect in the form of an air break.
CPC § 704.1 Medium relevance — show source text
Inlet, for fixture connections . . . . . . . . . . . .704.1, 704.2

Lead content . . . . . . . . . . . . . . . . . . . . . .604.2, 604.2.1

Material of . . . . . . . . . . . . . . . . . . . .604.0, Table 604.1,

Table 701.2, 701.3, 903.0,

1208.5, 1208.5.9, 1208.5.9.5

Medical gas

and medical vacuum . . . . . .1320.2, 1320.2.1, 1321.1

Plumbing vent . . . . . . . . . . . . . . . . . . . . . . . . . . . .903.0

Prohibited . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .310.1

Screwed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .310.8

Water supply system . . . . . . . . . . . .604.0, Table 604.1,

605.0, A 107.3

FIXTURE . . . . . . . . . . . . . . . . . . . . .(see Plumbing fixtures)

Branch, definition . . . . . . . . . . . . . . . . . . . . . . . . .208.0

Calculations . . . . . . . . . . . . . . . . . . . . . . . . . . . .422.1.1

Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . .704.0

Drain, definition . . . . . . . . . . . . . . . . . . . . . . . . . . .208.0

Flanged connection . . . . . . . . . . . . . . . . . . . . . . . .402.6

Future installations . . . . . . . . . . . . . . . . . . . . . . . .402.11

Plumbing . . . . . . . . . . . . . . . . . . (see Plumbing fixtures) Units, drainage (DFU) . . . . . . . . . . . 702.1, Table 702.1,

C 303.1, Table C 303.3

Units, water supply (WSFU) . . . . . . . 610.3, Table 610.3,

610.10, Table 610.10,

A 103.1, Table A 103.1,

C 303.1, Table C 303.2

FLAGPOLING OF VENTS . . . . . . . . . . . . . . . . . . . . . .906.3

FLAMMABLE VAPOR OR FUMES . . . . . . . . . . .208.0, 507.12

FLASHING . . . . . . . . . . . . . . . . . . . . . . . . .701.5, 906.5, 906.6,
CPC § 412.1.3 Medium relevance — show source text
PLUMBING FIXTURES AND FIXTURE FITTINGS

412.1.3 Nonwater Urinals. Nonwater urinals shall have a liquid barrier sealant to maintain a trap seal. Nonwater urinals shall permit the uninhibited flow of waste through the urinal to the sanitary drainage system. Nonwater urinals shall be cleaned and maintained in accor dance with the manufacturer’s instructions after

installation. Where nonwater urinals are installed, not less than one water supplied fixture rated at not less than 1 water supply fixture unit (WSFU) shall be installed upstream on the same drain line to facilitate drain line flow and rinsing. Where nonwater urinals are installed, they shall have a water distribution line rough-in to each individual urinal location to allow for the installation of an approved backflow prevention device in the event of a retrofit. For additional information, see Health and Safety Code Section 17921.4.

412.1.4 Nonwater Urinals with Drain Cleansing Action. Nonwater urinals with drain cleansing action shall comply with ASME A112.19.19 and shall be cleaned, maintained and installed in accordance with the manufacturer’s installation instructions.

412.1.4.1 [BSC-CG]. Where approved, nonwater urinals with drain cleansing action shall be in com- pliance with Chapter 5, Division A5.3 of the Cali- fornia Green Building Standards Code (CALGreen).

412.2 Backflow Protection. A water supply to a urinal shall be protected by an approved-type vacuum breaker or other approved backflow prevention device in accordance with Section 603.5.

413.0 Flushing Devices.

413.1 Where Required. Each water closet, urinal, clinical sink, or other plumbing fixture that depends on trap siphonage to discharge its waste contents shall be provided with a flushometer valve, flushometer tank, or flush tank designed and installed so as to supply water in sufficient quantity and rate of flow to flush the contents of the fixture to which it is connected, to cleanse the fixture, and to refill the fixture trap, without excessive water use. Flushing devices shall comply with the antisiphon requirements in accordance with Section 603.5.

413.2 Flushometer Valves. Flushometer valves and flushometer tanks shall comply with ASSE 1037/ASME A112.1037/CSA B125.37, and shall be installed in accordance with Section 603.5.1. No manually controlled flushometer valve shall be used to flush more than one urinal, and each such urinal flushometer valve shall be an approved, self-closing type discharging a predetermined quantity of water. Flushometers shall be installed so that they will be accessible for repair. Flushometer valves shall not be used where the water pressure is insufficient to operate them properly. Where the valve is operated, it shall complete the cycle of operation automatically, opening fully, and closing positively under the line water pressure. Each flushometer shall be provided with a means for regulating the flow through it.

[OSPHD 1, 2, 3, 4 & 5] Sensor operated flush valves shall be capable of functioning during loss of normal power.
CPC § 302.2 Medium relevance — show source text
E 302.2 Water Service Outlet. Each manufactured home lot shall be provided with a water service outlet delivering potable water. The water service outlet riser shall be not less than [3] ⁄ 4 of an inch (20 mm) nominal pipe size and capable of delivering 12 water supply fixture units.

E 302.2.1 Connection. A manufactured home shall be connected to the park water service outlet by a flexible connector, such as copper or copper alloy or other approved material not less than [3] ⁄ 4 of an inch nominal (20 mm) interior diameter.

E 302.2.2 Water Supply Fixture Units. Park water distribution systems shall be designed to deliver a minimum of 12 water supply fixture units to each lot and installed with materials in accordance with Chapter 6, Appendix A, or both of this code.

E 302.2.3 Pressure. Each manufactured home park water distribution system shall be so designed and maintained as to provide a pressure of not less than 20 poundsforce per square inch (psi) (138 kPa) at each manufactured home lot at maximum operating conditions.

E 302.2.4 Location. Each lot water service outlet shall be located in the third rear section and within 4 feet (1219 mm) of the proposed location of the manufactured home.

E 302.3 Shutoff Valve. A separate water shutoff valve shall be installed in each water service outlet at each manufactured home lot. Where a listed backflow protective device is installed, the service shutoff shall be located on the supply side of such device.

E 302.4 Backflow Preventer. Where a condition exists in the plumbing of a manufactured home that creates a crossconnection, a listed backflow preventer shall be installed in the water service line to the manufactured home at or near the

water service outlet. Where a hose bibb or outlet is installed on the supply outlet riser in addition to the service connector, a listed backflow preventer shall be installed on each additional outlet.

E 302.5 Pressure-Relief Valve. Where it is required to install a backflow preventer at the manufactured home lot service outlet, a listed pressure-relief valve shall be installed in the water service line on the discharge side of the backflow preventer. Pressure-relief valves shall be set to release at a pressure at a maximum of 150 psi (1034 kPa). Pressurerelief valves shall discharge toward the ground. Backflow preventers and pressure-relief valves shall be not less than 12 inches (305 mm) above the ground.

408 2025 CALIFORNIA PLUMBING CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

E 302.6 Mechanical Protection. Park water service out lets, backflow preventers, and pressure-relief valves shall be protected from damage by vehicles or other causes. Such protection shall be permitted to consist of posts, fencing, or other permanent barriers.

E 302.7 Water-Conditioning Equipment. A permit shall be obtained from the Authority Having Jurisdiction before installing water-conditioning equipment on a manufactured home lot. Approval of the park operator is required on applications for a permit to install such equipment. Where the water-conditioning equipment is of the regenerating type, and the park drainage system discharges into a public sewer, approval of the sanitary district or agency having jurisdiction over the public sewer is required.

CPC § 301.2.4 Medium relevance — show source text

2025 CALIFORNIA PLUMBING CODE 345

REFERENCED STANDARDS

TABLE 1701.1 (continued) REFERENCED STANDARDS

STANDARD NUMBER	STANDARD TITLE	APPLICATION	REFERENCED SECTION
CSA B45.11-2017/IAPMO Z401-2017 (R2021)	Glass Plumbing Fixtures	Fixtures	407.1
CSA B45.12-2013/IAPMO Z402-2013 (R2018)	Aluminum and Copper Plumbing Fixtures	Fixtures	407.1, 408.1, 409.1, 420.1
ASME A112.19.5- 2017/CSA B45.15-2017	Flush Valves and Spuds for Water Closets, Urinals, and Tanks	Fixtures	413.3
ASME A112.4.

Frequently asked questions

Do fixtures have to be installed exactly per the manufacturer’s instructions?

Yes. The CPC requires fixtures to be installed in accordance with the manufacturer’s installation instructions, and that such installations not compromise backflow prevention or other code requirements (see §402.8 and §402.9).

What materials and fasteners are required for closet flanges and fixture anchors?

Closet rings (flanges) and the screws/bolts that secure fixtures must be of approved materials and corrosion-resistant metals (copper, copper alloy, or other listed corrosion‑resistant materials) sized and numbered to properly support the fixture, per §402.6 and §402.6.2.

Are concealed slip-joint connections allowed, and must they be accessible?

Concealed slip‑joint connections are permitted only if an access panel or utility space (minimum 12 inches in least dimension) is provided so those connections are accessible for inspection and repair, per §402.10.

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