CPC · California Plumbing Code

What water‑conserving flow and efficiency requirements apply to fixtures?

Q: Do showerheads have to be WaterSense‑listed to meet the CPC?

Table L 402.1 includes a note that showerheads shall be listed to EPA WaterSense specifications where the note applies. Check the table notes under § L 402.1 for the exact listing requirement.

Q: Where can I find pre‑rinse spray valve requirements?

The table refers to Section L 402.9 for commercial pre‑rinse spray valves — consult that subsection in Appendix L for the specific limits and test method.

The CPC requires fixtures to meet the maximum flows/flushes in Appendix L, Table L 402.1 (for example, showerheads 2.0 gpm @80 psi, residential lavatory faucets 1.5 gpm @60 psi, toilets 1.28 gpf) and § 401.3 says water‑conserving fixtures must be used; when a different California regulation sets a lower limit, the lower value controls.

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Last reviewed: July 6, 2026

What the code requires — plain English

The California Plumbing Code requires that plumbing fixtures and fixture fittings not exceed the maximum water consumption values shown in Table L 402.1. The general mandate for water‑conserving fixtures is stated in § 401.3 and the specific maximum flows/flush volumes are set by § L 402.1 (Table L 402.1).

The short rule: pick fixtures whose flow (gpm) or flush volume (gpf) is at or below the values in Table L 402.1; those values are the CPC maximums.

Requirements in detail

Key defined terms and thresholds (first mention bolded): § 401.3 (water‑conserving fixtures requirement) and § L 402.1 (maximum flows table).

What Table L 402.1 controls

Table L 402.1 in Appendix L lists the maximum flow rates and maximum flush volumes for common fixture types. The table is the compliance baseline referenced by § L 402.1.

Decision‑relevant values (use these when specifying or verifying fixtures):

Fixture type	Maximum flow / volume (CPC)	Test pressure / unit	Code Reference
Showerheads	2.0 gpm	at 80 psi	§ L 402.1 — Table L 402.1
Kitchen faucets (residential)	1.8 gpm	at 60 psi	§ L 402.1 — Table L 402.1
Lavatory faucets (residential)	1.5 gpm	at 60 psi	§ L 402.1 — Table L 402.1
Lavatory faucets (other than residential)	0.5 gpm	at 60 psi	§ L 402.1 — Table L 402.1
Metering faucets	0.25 gallons/cycle	—	§ L 402.1 — Table L 402.1
Wash‑fountain fitting	2.2 gpm per 20 in rim space	at 60 psi	§ L 402.1 — Table L 402.1
Water closets (toilets)	1.28 gallons/flush (gpf)	—	§ L 402.1 — Table L 402.1
Urinals	0.5 gallons/flush (gpf)	—	§ L 402.1 — Table L 402.1
Commercial pre‑rinse spray valves	See Section L 402.9 (table refers out)	—	§ L 402.1 — Table L 402.1; cross‑ref

Notes in the table: showerheads must be listed to EPA WaterSense specifications and certain items are cross‑referenced to other Appendix L sections — see the table notes in § L 402.1 for those listings and cross‑references.

How § 401.3 fits in

§ 401.3 is the chapter‑level policy statement: plumbing fixtures and fittings must be water‑conserving. It also includes a key rule that if other California regulations (for example Title 20 appliance efficiency regulations) set a lower maximum flow the lower value controls. That means you must comply with the strictest applicable mandate.

Exceptions & special cases

Appendix L itself points to further appliance‑specific or occupancy‑specific rules (e.g., commercial pre‑rinse valves are handled in L 402.9). Consult the referenced sub‑sections in Appendix L for special fittings. The table in § L 402.1 cross‑references L 402.2–L 402.10 for those details.
Where another California regulation sets a lower maximum (for example an appliance efficiency standard adopted in Title 20), that lower limit supersedes the values in Chapter 4 — this precedence is explicitly noted in § 401.3.
The table includes notes (e.g., showerheads listed to EPA WaterSense). For items with listing or performance requirements, the listing is a condition of compliance; check the table notes in § L 402.1 for the exact listing/verification language.
If a fixture type or specialized fitting you’re using is not listed in Table L 402.1, Appendix L directs you to the applicable L 402.x subsection or to consult the authority having jurisdiction. The table itself is the starting point; absence means you must find the related L‑section or ask the AHJ.

If a specific sub‑provision (for example, the full text on multiple showerheads in Appendix L) is not fully visible in the retrieved CPC excerpts here, I will not invent it — you should check the official Table L 402.1 notes and the L 402.x sections in the full CPC for those details.

Common mistakes

Confusing residential vs nonresidential lavatory limits — Table L 402.1 sets 1.5 gpm for residential lavatories but 0.5 gpm for lavatories other than residential (different rules apply to each). Verify the facility classification before choosing a faucet.
Relying on manufacturer “low‑flow” claims without checking test pressure/conditions — the CPC table specifies pressures (e.g., 60 psi or 80 psi) at which the maximum flow is measured. Use manufacturer data showing flow at the referenced pressure to confirm compliance.
Ignoring higher‑priority state regulations — § 401.3 notes that where appliance efficiency law (Title 20) has a lower flow requirement, that lower value controls. Don’t assume the table is always the strictest limit.
Treating WaterSense certification as optional — the table note requires showerheads to be listed to EPA WaterSense; if the table footnote applies, listing is part of compliance. Check the table note text in § L 402.1.

Worked example — selecting fixtures for a small residential bathroom

Scenario: single‑family bathroom (one shower, one lavatory faucet, one toilet).

Use the maximums from Table L 402.1 (under § L 402.1):

Choose showerhead ≤ 2.0 gpm at 80 psi. (Table L 402.1 maximum = 2.0 gpm.)
Choose residential lavatory faucet ≤ 1.5 gpm at 60 psi. (Table L 402.1 maximum = 1.5 gpm.)
Choose water closet ≤ 1.28 gpf. (Table L 402.1 maximum = 1.28 gpf.)

Practical check: ask manufacturers for the certified flow at the test pressure(s) stated in the table. If the chosen showerhead is listed to EPA WaterSense and rated at 1.8 gpm (at 80 psi), the fixture meets CPC table limits for showers. If Title 20 or local ordinance requires a lower flow, the lower limit must be used instead — per § 401.3.

Related CPC provisions

§ 401.2 — Quality of fixtures (materials, finish and cleanability).
§ 402.1 — Installation: cleaning/access requirements for fixtures (installation practices).
§ L 401.1 — Scope for Appendix L (water conservation and efficiency).
§ L 402.1 — (Primary table of maximum flows / Table L 402.1).
Appendix L — see L 402.2 through L 402.10 for fixture‑specific rules and notes referenced by Table L 402.1.

If you need the verbatim table notes, the text for L 402.2–L 402.10, or the cross‑references (for example the exact WaterSense listing language or the full note on multiple showerheads), I can extract those specific subsections from the CPC and cite them directly.

Code references

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

CPC § 302.0 High relevance — show source text

L 302.0 Disposal of Liquid Waste.

L 302.1 Disposal. It shall be unlawful for a person to cause, suffer, or permit the disposal of sewage, human excrement, or other liquid wastes, in a place or manner, except through and by means of an approved drainage system, installed and maintained in accordance with the provisions of this code. L 302.2 Connections to Plumbing System Required. Equipment and appliances, used to receive or discharge liquid wastes or sewage, shall be connected properly to the drainage system of the building or premises, in accordance with the requirements of this code.

500 2025 CALIFORNIA PLUMBING CODE

APPENDIX L

L 303.0 Abandonment.

L 303.1 General. An abandoned system or part thereof covered under the scope of this appendix shall be disconnected from remaining systems, drained, plugged, and capped in an approved manner.

L 401.0 Water Conservation and Efficiency. L 401.1 Scope. The provisions of this section establish the means of conserving potable and nonpotable water used in and around a building.

L 402.0 Water-Conserving Plumbing Fixtures and Fittings. L 402.1 General. The maximum water consumption of fixtures and fixture fittings shall comply with the flow rates specified in Table L 402.1, and Section L 402.2 through Section L 402.10.

TABLE L 402.1

MAXIMUM FIXTURE AND FIXTURE FITTINGS FLOW RATES

FIXTURE TYPE	FLOW RATE
Showerheads	2.0 gpm at 80 psi1
Kitchen faucets residential4	1.8 gpm at 60 psi
Lavatory faucets residential5	1.5 gpm at 60 psi
Lavatory faucets other than residential	0.5 gpm at 60 psi
Metering faucets	0.25 gallons/cycle
Metering faucets for wash fountains	One 0.25 gallons/cycle fixture fit- ting for each 20 inches rim space
Wash fountains	One 2.2 gpm at 60 psi fixture fit- ting for each 20 inches rim space
Water Closets	1.28 gallons/flush2
Urinals	0.5 gallons/flush3
Commercial Pre-Rinse Spray Valves	See Section L 402.9

For SI units: 1 gallon per minute = 0.06 L/s, 1 pound-force per square inch = 6.8947 kPa, 1 inch = 25.4 mm, 1 gallon = 3.785 L

Notes: 1 Shall be listed to EPA WaterSense Specification for Showerheads. For multiple showerheads serving one shower compartment see Section L

CPC § 1.11.0. High relevance — show source text

This 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 1.11.0.

2025 CALIFORNIA PLUMBING CODE 517

518 2025 CALIFORNIA PLUMBING CODE

APPENDIX M

PEAK WATER DEMAND CALCULATOR

The provisions contained in this appendix are not mandatory unless specifically adopted by a state agency, or referenced in the adopting ordinance.

M 101.0 General.

M 101.1 Applicability. This appendix provides an alterna- tive method for estimating the demand load for the building water supply and principal branches for single- and multifamily dwellings with water-conserving plumbing fixtures, fixture fittings, and appliances.

M 102.0 Demand Load.

M 102.1 Water-Conserving Fixtures. Plumbing fixtures, fixture fittings, and appliances shall not exceed the design flow rate in Table M 102.1.

TABLE M 102.1

DESIGN FLOW RATE FOR WATER-CONSERVING PLUMBING

FIXTURES AND APPLIANCES IN RESIDENTIAL OCCUPANCIES

FIXTURE AND APPLIANCE	MAXIMUM DESIGN FLOW RATE (gallons per minute)
Bar Sink	1.5
Bathtub	5.5
Bidet	2.0
Clothes Washer	3.5
Combination Bath/Shower	5.5
Dishwasher	1.3
Kitchen Faucet	1.8
Laundry Faucet (with aerator)	2.0
Lavatory Faucet	1.2
Shower, per head	1.8
Water Closet, 1.28 GPF Gravity Tank	3.0

For SI units: 1 gallon per minute = 0.06 L/s

M 102.2 Water Demand Calculator. The estimated design flow rate for the building supply and principal branches and risers shall be determined by the IAPMO Water Demand Calculator available for download at http://www.iapmo.org/ WEStand/Pages/WaterDemandCalculator.aspx

M 102.3 Meter and Building Supply. To determine the design flow rate for the water meter and building supply, enter the total number of indoor plumbing fixtures and appliances for the building in Column [B] of the Water Demand Calculator and run Calculator. See Table M 102.3 for an example.

M 102.4 Fixture Branches and Fixture Supplies. To determine the design flow rate for fixture branches and risers, enter the total number of plumbing fixtures and appliances

TABLE M 102.1

DESIGN FLOW RATE FOR WATER-CONSERVING PLUMBING

FIXTURES AND APPLIANCES IN RESIDENTIAL OCCUPANCIES

CPC § 3.4.2 High relevance — show source text
Add 5 gpm to the flow rate required by Section_R309.3.4.2_ where the water service pipe supplies more than one dwelling.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 0.063 L/s, 1 pound per square inch = 6.895 kPa.
NP = Not Permitted. Pressure loss exceeds reasonable limits.
a. Values are applicable for underground piping materials listed in_ the California Plumbing Code_ and are based on an SDR of 11 and a Hazen Williams C Factor of 150.
b. Values include the following length allowances for fittings: 25-percent length increase for actual lengths up to 100 feet and 15-percent length increase for actual lengths over
100 feet.
c. Flow rate from Section P2904.4.2. Add 5 gpm to the flow rate required by Section_R309.3.4.2_ where the water service pipe supplies more than one dwelling.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 0.063 L/s, 1 pound per square inch = 6.895 kPa.
NP = Not Permitted. Pressure loss exceeds reasonable limits.
a. Values are applicable for underground piping materials listed in_ the California Plumbing Code_ and are based on an SDR of 11 and a Hazen Williams C Factor of 150.
b. Values include the following length allowances for fittings: 25-percent length increase for actual lengths up to 100 feet and 15-percent length increase for actual lengths over
100 feet.
c. Flow rate from Section P2904.4.2. Add 5 gpm to the flow rate required by Section_R309.3.4.2_ where the water service pipe supplies more than one dwelling.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 0.063 L/s, 1 pound per square inch = 6.895 kPa.
NP = Not Permitted. Pressure loss exceeds reasonable limits.
a. Values are applicable for underground piping materials listed in_ the California Plumbing Code_ and are based on an SDR of 11 and a Hazen Williams C Factor of 150.
b. Values include the following length allowances for fittings: 25-percent length increase for actual lengths up to 100 feet and 15-percent length increase for actual lengths over
100 feet.
c. Flow rate from Section P2904.4.2. Add 5 gpm to the flow rate required by Section_R309.3.4.2_ where the water service pipe supplies more than one dwelling.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 0.063 L/s, 1 pound per square inch = 6.895 kPa.
NP = Not Permitted. Pressure loss exceeds reasonable limits.
a. Values are applicable for underground piping materials listed in_ the California Plumbing Code_ and are based on an SDR of 11 and a Hazen Williams C Factor of 150.
b. Values include the following length allowances for fittings: 25-percent length increase for actual lengths up to 100 feet and 15-percent length increase for actual lengths over
100 feet.
c. Flow rate from Section P2904.4.2.
CPC § 4-8 High relevance — show source text
4-8 2025 CALIFORNIA GREEN BUILDING STANDARDS CODE

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

4 RESIDENTIAL MANDATORY MEASURES

DIVISION 4.3 – WATER EFFICIENCY AND CONSERVATION

SECTION 4.301—GENERAL

4.301.1 Scope. The provisions of this chapter shall establish the means of conserving water used indoors, outdoors and in wastewater conveyance.

SECTION 4.302—DEFINITIONS

4.302.1 Definitions. Reserved.

SECTION 4.303—INDOOR WATER USE

4.303.1 Water conserving plumbing fixtures and fittings. Plumbing fixtures (water closets and urinals) and fittings (faucets and showerheads) shall comply with Sections 4.303.1.1, 4.303.1.2, 4.303.1.3 and 4.303.1.4.

Note: All noncompliant plumbing fixtures in any residential real property shall be replaced with water-conserving plumbing fixtures. 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 definition of a noncompliant plumbing fixture, types of residential buildings affected and other important enactment dates.

4.303.1.1 Water closets. The effective flush volume of all water closets shall not exceed 1.28 gallons per flush. Tank-type water closets shall be certified to the performance criteria of the US EPA WaterSense Specification for Tank-type Toilets.

Note: The effective flush volume of dual flush toilets is defined as the composite, average flush volume of two reduced flushes and one full flush.

4.303.1.2 Urinals. The effective flush volume of wall-mounted urinals shall not exceed 0.125 gallons per flush. The effective flush volume of all other urinals shall not exceed 0.5 gallons per flush.

4.303.1.3 Showerheads.

4.303.1.3.1 Single showerhead. Showerheads shall have a maximum flow rate of not more than 1.8 gallons per minute at 80 psi. Showerheads shall be certified to the performance criteria of the US EPA WaterSense Specification for Showerheads.

4.303.1.3.2 Multiple showerheads serving one shower. When a shower is served by more than one showerhead, the combined flow rate of all showerheads and/or other shower outlets controlled by a single valve shall not exceed 1.8 gallons per minute at 80 psi, or the shower shall be designed to allow only one shower outlet to be in operation at a time.

Note: A hand-held shower shall be considered a showerhead.

4.303.1.4 Faucets.

4.303.1.4.1 Residential lavatory faucets. The maximum flow rate of residential lavatory faucets shall not exceed 1.2 gallons per minute at 60 psi. The minimum flow rate of residential lavatory faucets shall not be less than 0.8 gallons per minute at 20 psi.
CPC § 401.2 High relevance — show source text
401.2 Quality of Fixtures. Plumbing fixtures shall be constructed of dense, durable, non-absorbent materials and shall have smooth, impervious surfaces, free from unnecessary concealed fouling surfaces. 401.3 Water-Conserving Fixtures and Fittings. Note 1: [BSC-CG & DSA-SS] Flow rates for specified plumbing fixtures for mandatory nonresidential construction are contained in Chapter 5, Division 5.3 of the California Green Building Standards Code (Part 11, Title 24, Califor- nia Code of Regulations - CALGreen). Scoping provisions applicable to nonresidential additions and alterations are contained in Section 301.3 of CALGreen. Note 2: [BSC-CG] On and after January 1, 2014, certain commercial real property, as defined in Civil Code Section 1101.3, shall have its noncompliant plumbing fixtures replaced with appropriate water-conserving plumbing fix- tures under specific circumstances. See Civil Code Section 1101.1 et seq. for definitions, types of commercial real prop- erty affected, effective dates, circumstances necessitating replacement of noncompliant plumbing fixtures, and duties and responsibilities for ensuring compliance.

[HCD-1] All noncompliant plumbing fixtures in any residen- tial real property shall be replaced with water-conserving plumbing fixtures. 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.
CPC § 0.06 High relevance — show source text
For SI units: 1 gallon per minute = 0.06 L/s

M 102.2 Water Demand Calculator. The estimated design flow rate for the building supply and principal branches and risers shall be determined by the IAPMO Water Demand Calculator available for download at http://www.iapmo.org/ WEStand/Pages/WaterDemandCalculator.aspx

M 102.3 Meter and Building Supply. To determine the design flow rate for the water meter and building supply, enter the total number of indoor plumbing fixtures and appliances for the building in Column [B] of the Water Demand Calculator and run Calculator. See Table M 102.3 for an example.

M 102.4 Fixture Branches and Fixture Supplies. To determine the design flow rate for fixture branches and risers, enter the total number of plumbing fixtures and appliances

TABLE M 102.1

DESIGN FLOW RATE FOR WATER-CONSERVING PLUMBING

FIXTURES AND APPLIANCES IN RESIDENTIAL OCCUPANCIES

for the fixture branch or riser in Column [B] of the Water Demand Calculator and run Calculator. The flow rate for one fixture branch and one fixture supply shall be the design flow rate of the fixture according to Table M 102.1.

M 102.5 Continuous Supply Demand. Continuous supply demands in gallons per minute (gpm) for lawn sprinklers, air conditioners, hose bibbs, etc., shall be added to the total estimated demand for the building supply as determined by Section M 102.3. Where there is more than one hose bibb installed

on the plumbing system, the demand for only one hose bibb shall be added to the total estimated demand for the building supply. Where a hose bibb is installed on a fixture branch, the demand of the hose bibb shall be added to the design flow rate for the fixture branch as determined by Section M 102.4.

M 102.6 Other Fixtures. Fixtures not included in Table M

102.1 shall be added in Rows 12 through 14 in the Water Demand Calculator as Other Fixture. The probability of use and flow rate for Other Fixtures shall be added by selecting the comparable probability of use and flow rate from Columns

[C] and [E].

M 102.7 Size of Water Piping per Appendix A. Except as provided in Section M 102.0 for estimating the demand load for single- and multi-family dwellings, the size of each water piping system shall be determined in accordance with the procedure set forth in Appendix A. After determining the permissible friction loss per 100 feet (30 480 mm) of pipe in accordance with Section A 104.0 and the demand flow in

accordance with the Water Demand Calculator, the diameter of the building supply pipe, branches and risers shall be obtained from Chart A 105.1(1) through Chart A 105.1(7), whichever is applicable, in accordance with Section A 105.0 and Section A 106.0. Velocities shall be in accordance with

Section A 107.0. Appendix I (IS 31), Figure 3 and Figure 4 shall be permitted when sizing PEX systems.

M 102.7.1 Minimum Fixture Branch Size. The minimum fixture branch size shall be [1] / 2 inch (15 mm) in diameter.

For SI units: 1 gallon per minute = 0.06 L/s

2025 CALIFORNIA PLUMBING CODE 519
CPC § 301.0 High relevance — show source text
Submeter. A meter installed subordinate to a site meter.

Also known as a dedicated meter.

WaterSense. A voluntary program of the U.S., Environmental Protection Agency, designed to identify and promote water-efficient products and practices. Water Closet. A fixture with a water-containing receptor that receives liquid and solid body waste and on actuation conveys the waste through an exposed integral trap into a drainage system. Also referred to as a toilet.

L 301.0 General Regulations. L 301.1 Installation. Plumbing systems covered by this appendix shall be installed in accordance with this code, other applicable codes, and the manufacturer’s installation instructions.

L 301.2 Qualifications. 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.

L 302.0 Disposal of Liquid Waste.

L 302.1 Disposal. It shall be unlawful for a person to cause, suffer, or permit the disposal of sewage, human excrement, or other liquid wastes, in a place or manner, except through and by means of an approved drainage system, installed and maintained in accordance with the provisions of this code. L 302.2 Connections to Plumbing System Required. Equipment and appliances, used to receive or discharge liquid wastes or sewage, shall be connected properly to the drainage system of the building or premises, in accordance with the requirements of this code.

500 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 L

L 303.0 Abandonment.

L 303.1 General. An abandoned system or part thereof covered under the scope of this appendix shall be disconnected from remaining systems, drained, plugged, and capped in an approved manner.

L 401.0 Water Conservation and Efficiency. L 401.1 Scope. The provisions of this section establish the means of conserving potable and nonpotable water used in and around a building.

L 402.0 Water-Conserving Plumbing Fixtures and Fittings. L 402.1 General. The maximum water consumption of fixtures and fixture fittings shall comply with the flow rates specified in Table L 402.1, and Section L 402.2 through Section L 402.10.

TABLE L 402.1

MAXIMUM FIXTURE AND FIXTURE FITTINGS FLOW RATES
CPC § 501.3.1 High relevance — show source text
E 501.3.1, E 501.6

Prohibited . . . . . . . . . . . . . . . . . . . . . . . . . .405.1, 910.7

Seats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .411.3

Water consumption . . . . . . . . . . . . . . . . .411.2, L 402.2

WATER-CONSERVING

FIXTURES AND FITTINGS . . . . . . . . . . . . . 401.3, L 402.0

WATER CONSUMPTION

Lavatories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .407.2

Showerhead & body sprays . . . . . . . . . . . .408.2, 408.3

Water closets . . . . . . . . . . . . . . . . . . . . . . . . . . . . .411.2

WATER HAMMER ARRESTORS . . . . . . . . . .225.0, 609.11

WATER HEATERS . . . . . . . . . . . . . . . . . . . . . . . .Chapter 5

Access . . . . . . . . . . . . . . . . . . . . . . . .504.3.1, 507.13.2,

507.25, 508.4

Approval requirements . . . . . . . . . . . . . . . . . . . . . .501.1 Approved standards . . . . . .Table 501.1(1), 505.3, 505.4 Clearances. . . . . . . . . . . . . . . . . . . . . . 504.3 – 504.3.2,

508.1, 508.2.1

Combustion air required . . . . . . . . . . . . . . . . . . . .506.0

Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . .604.13

Dual purpose, definition . . . . . . . . . . . . . . . . . . . .225.0

Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .225.0

Garages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .507.13 Inspections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .503.2

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .507.0

Location . . . . . . . . . . . . . . . . . . .504.1, 507.12 – 507.15

CPC § 101.1 High relevance — show source text

APPENDIX M - PEAK WATER DEMAND CALCULATOR

(Matrix Adoption Tables are non-regulatory, 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
Adopt Entire Chapter as amended (amended sections listed below)				X
Adopt only those sections that are listed below
Chapter/Section
M 101.1				X
Table M 102.1				X

2025 CALIFORNIA PLUMBING CODE 517

518 2025 CALIFORNIA PLUMBING CODE

APPENDIX M

PEAK WATER DEMAND CALCULATOR

The provisions contained in this appendix are not mandatory unless specifically adopted by a state agency, or referenced in the adopting ordinance.

M 101.0 General.

M 102.0 Demand Load.

M 102.1 Water-Conserving Fixtures. Plumbing fixtures, fixture fittings, and appliances shall not exceed the design flow rate in Table M 102.1.

TABLE M 102.1

DESIGN FLOW RATE FOR WATER-CONSERVING PLUMBING

FIXTURES AND APPLIANCES IN RESIDENTIAL OCCUPANCIES

CPC § 110.2 High relevance — show source text
Water-to-water heat pumps with a capacity less than 135,000 Btu/h are included in Table 110.2-B, Heat Pumps—Minimum Efficiency Requirements.
i. Source leaving liquid temperature.
1. The cooling evaporator liquid flow rate used for the heating rating for a reverse cycle air-to-water heat pump shall be the flow rate determined during the full load cooling rating.
2. The cooling evaporator liquid flow rate for the simultaneous cooling and heating and heat recovery liquid cooled chilling packages rating shall be the liquid flow rates
from the cooling operation full-load rating.
3. For heating-only fluid-to-fluid chiller packages, the evaporator flow rate obtained with an entering liquid temperature of 54°F and a leaving liquid temperature of 44°F
shall be used.
j. NA means the requirements are not applicable.|a. The size category is the full-load net refrigeration cooling mode capacity, which is the capacity of the evaporator available for cooling of the thermal load external to the chill-
ing package.
b. For air source heat pumps, compliance with both the 47°F and 17°F heating source outdoor air temperature (OAT) rating efficiency is required for heating.
c. Heating full-load rating conditions are at standard rating conditions defined in AHRI 550/590 (I-P), Table 4, includes the impact of defrost for air source heating ratings.
d. For units that operate in both cooling and heating, compliance with both the cooling and heating efficiency is required.
e. For heat recovery heating chilling package applications where there is simultaneous cooling and heating, compliance with the heating performance heat recover COPHR is
only required at one of the four heating AHRI 550/590 (I-P) standard ratings conditions of Low, Medium, Hot-Water 1 or Hot-Water 2. Compliance with the cooling-only perfor-
mance is required as defined in Notes b and c of Table 110.2-I.
f. For applications where the chilling package is installed to operate only in heating, compliance only with the heating performance COPH is required at only one of the heating
AHRI 550/590 (I-P) standard rating conditions of Low, Medium, High, or Boost. Compliance with cooling performance is not required.
g. For heat pump chilling package applications where the cooling capacity is not being used for conditioning, compliance with the heating performance COPH is only required at
one of the heating AHRI 550/590 (I-P) standard rating conditions of Low, Medium, High, or Boost. Compliance with the cooling performance is required as defined in Notes b
and c of Table 110.2-I, except as noted in Note f.
h. Water-to-water heat pumps with a capacity less than 135,000 Btu/h are included in Table 110.2-B, Heat Pumps—Minimum Efficiency Requirements.
i. Source leaving liquid temperature.
1. The cooling evaporator liquid flow rate used for the heating rating for a reverse cycle air-to-water heat pump shall be the flow rate determined during the full load cooling rating.
2. The cooling evaporator liquid flow rate for the simultaneous cooling and heating and heat recovery liquid cooled chilling packages rating shall be the liquid flow rates
from the cooling operation full-load rating.
3. For heating-only fluid-to-fluid chiller packages, the evaporator flow rate obtained with an entering liquid temperature of 54°F and a leaving liquid temperature of 44°F
shall be used.
j. NA means the requirements are not applicable.|a.
CPC § 110.2 High relevance — show source text
Compliance with the cooling-only perfor-
mance is required as defined in Notes b and c of Table 110.2-I.
h. Water-to-water heat pumps with a capacity less than 135,000 Btu/h are included in Table 110.2-B, Heat Pumps—Minimum Efficiency Requirements.
i. Source leaving liquid temperature.
1. The cooling evaporator liquid flow rate used for the heating rating for a reverse cycle air-to-water heat pump shall be the flow rate determined during the full-load cool-
ing rating.
2. The cooling evaporator liquid flow rate for the simultaneous cooling and heating and heat recovery liquid cooled chilling packages rating shall be the liquid flow rates
from the cooling operation full-load rating.
3. For heating-only fluid-to-fluid chiller packages, the evaporator flow rate obtained with an entering liquid temperature of 54°F and a leaving liquid temperature of 44°F
shall be used.
j. NA means the requirements are not applicable.|a. The size category is the full-load net refrigeration cooling mode capacity, which is the capacity of the evaporator available for cooling of the thermal load external to the chill-
ing package.
b. For air source heat pumps, compliance with both the 47°F and 17°F heating source outdoor air temperature (OAT) rating efficiency is required for heating.
c. Heating full-load rating conditions are at standard rating conditions defined in AHRI 550/590 (I-P), Table 4, which includes the impact of defrost for air source heating ratings.
d. For units that operate in both cooling and heating, compliance with both the cooling and heating efficiency is required.
e. For heat recovery heating chilling package applications where there is simultaneous cooling and heating, compliance with the heating performance heat recover COPHR is
only required at one of the four heating AHRI 550/590 (I-P) standard ratings conditions of Low, Medium, Hot-Water 1 or Hot-Water 2. Compliance with the cooling-only perfor-
mance is required as defined in Notes b and c of Table 110.2-I.
f. For liquid source heat recovery chilling packages that have capabilities for heat rejection to a heat recovery condenser and a tower condenser, the COPHR applies to operation
at full load with 100 percent heat recovery (no tower rejection). Units that only have capabilities for partial heat recovery shall meet the requirements of Table 110.2-D, Water
Chilling Packages—Minimum Efficiency Requirements.
g. For heat recovery heating chilling package applications where there is simultaneous cooling and heating, compliance with the heating performance heat recover COPHR is
only required at one of the four heating AHRI 550/590 (I-P) standard ratings conditions of Low, Medium, Hot-Water 1 or Hot-Water 2. Compliance with the cooling-only perfor-
mance is required as defined in Notes b and c of Table 110.2-I.
h. Water-to-water heat pumps with a capacity less than 135,000 Btu/h are included in Table 110.2-B, Heat Pumps—Minimum Efficiency Requirements.
i. Source leaving liquid temperature.
1. The cooling evaporator liquid flow rate used for the heating rating for a reverse cycle air-to-water heat pump shall be the flow rate determined during the full-load cool-
ing rating.
2. The cooling evaporator liquid flow rate for the simultaneous cooling and heating and heat recovery liquid cooled chilling packages rating shall be the liquid flow rates
from the cooling operation full-load rating.
3.

Frequently asked questions

Can I use fixtures that are “lower flow” than Table L 402.1 specifies?

Yes — lower flow fixtures are allowed; the table lists maximums. However if another California regulation or appliance standard sets a lower maximum, the stricter rule applies (see § 401.3).

Do showerheads have to be WaterSense‑listed to meet the CPC?

Table L 402.1 includes a note that showerheads shall be listed to EPA WaterSense specifications where the note applies. Check the table notes under § L 402.1 for the exact listing requirement.

Which pressure do I use to verify faucet/shower flows?

Use the test pressure specified in Table L 402.1 for each fixture (for example 60 psi for most faucets and 80 psi for showerheads) and confirm the manufacturer’s rated flow at that pressure.

What if my project is nonresidential?

Appendix L’s Table L 402.1 and the L 402.x sections apply; also note § 401.3 indicates mandatory nonresidential flow rates may additionally be governed by CALGreen Chapter 5 (see CPC notes). Verify occupancy classification and applicable state/local adoptions.

Where can I find pre‑rinse spray valve requirements?

The table refers to Section L 402.9 for commercial pre‑rinse spray valves — consult that subsection in Appendix L for the specific limits and test method.

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