CPC · California Plumbing Code

How do I size piping using the CPC pipe sizing tables?

Q: Can I use the CPC tables for both natural gas and propane?

Yes — the CPC provides separate table sets for natural gas and propane in § 1215.2 ; be sure you read the correct table for the fuel type and inlet pressure indicated.

Q: When should I use the equations in § 1215.3 instead of the tables?

Use § 1215.3 (equations and Table 1215.3) for smooth‑walled tubing (non‑corrugated stainless steel tubing) or when you prefer/need an engineered calculation; the code explicitly allows equations as the sizing method.

Q: Do I have to include fittings when I measure length?

Yes — you must use the equivalent length (straight pipe length plus fittings converted to equivalent feet) when looking up lengths in the tables or using the equations, per the methods in § 1215.1 .

Q: I can’t find § 1215.4 or § 1215.5 in my copy — is that normal?

In the uploaded files I was able to retrieve § 1215.1–1215.3 , but I could not find the text of § 1215.4 or § 1215.5 in the provided excerpts. If your printed code contains those sections, follow them; otherwise check the full CPC/approved edition or contact your Authority Having Jurisdiction.

To size gas piping under the CPC: determine each section’s total gas demand and *equivalent length*, pick the correct CPC table for your gas and pressure and read the pipe diameter at the table row matching that demand and length (or compute inside diameter using the equations in **§ 1215.3**). Use the longest‑length, branch‑length or hybrid method in **§ 1215.1** and check minimum outlet sizes in **§ 1214.4**.

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Last reviewed: July 6, 2026

What the code requires — plain English

The California Plumbing Code requires you to size gas piping either from the CPC pipe-sizing tables or from the CPC sizing equations, using one of the prescribed layout methods (the longest‑length, branch‑length, or hybrid‑pressure methods). Follow the procedures in § 1215.1 and use the tables in § 1215.2 or the equations in § 1215.3 to determine each pipe segment diameter.

The single most important rule: size each pipe section using the method in § 1215.1 and then pick the pipe diameter from the appropriate table (or calculate it using the equations in § 1215.3) for the section’s total gas demand and its equivalent length.

Requirements in detail

Key defined terms (first use bolded)

Equivalent length — the length of pipe in feet used for table/equation lookup; includes straight length plus fittings converted to length equivalents (used with the methods of § 1215.1).
Inside diameter — when using the sizing equations in § 1215.3, you compute the pipe inside diameter (D) per the code equations and Table 1215.3.
Longest‑length method, Branch‑length method, Hybrid‑pressure method — the three permitted approaches to determine the length/load pair used with the tables or equations; these are described in § 1215.1.

Which code text controls what

Use the table sets in § 1215.2 (natural gas tables and propane tables) together with the methods in § 1215.1 for most pipe materials; Section § 1215.3 provides sizing equations for smooth‑walled tubing and for situations where the equations are preferred.

Note: I was able to retrieve the text of § 1215.3 (sizing equations) and the procedures in § 1215.1–1215.2 from the uploaded CPC files. I could not retrieve the text of § 1215.4 or § 1215.5 from the provided files; I will mark where those sections would apply below and avoid inventing their content.

Step-by-step decision table (what you need to know)

Decision input	What to use	Where code says so (Code Reference)
Are you using standard metallic pipe or non‑corrugated stainless steel tubing?	Use the pipe sizing tables in § 1215.2 for the appropriate gas (natural gas or propane).	§ 1215.2 (Tables 1215.2(1)–(36))
Are you sizing smooth‑walled pipe/tubing (or prefer equations)?	Use the sizing equations (Equation 1215.3(1), 1215.3(2)) and Table 1215.3 with the calculated equivalent length.	§ 1215.3
Which layout method to calculate length/load?	Use Longest‑Length, Branch‑Length or Hybrid‑Pressure method as described.	§ 1215.1.1 – § 1215.1.3
Minimum outlet size	Piping outlet for an appliance shall be not less than 1/2‑inch (15 mm) (mobile home minimum 3/4‑inch (20 mm)).	§ 1214.4

(Use the table for the gas type and the inlet pressure/allowable pressure drop specified in the table heading. The CPC tables include separate sets for natural gas and propane and for pressure ranges.)

Exceptions & special cases

The CPC lets you use manufacturer listed sizing tables for a listed piping system in place of code tables — follow the manufacturer’s instructions where the system is listed. (This is an accepted alternative sizing source in the fuel‑gas chapters.)
If conditions fall outside the range of the tables (longer runs, higher demand, higher or variable pressures), you must use standard engineering methods and have the design acceptable to the Authority Having Jurisdiction. (This is stated generally in the fuel‑gas sizing provisions.)
The uploaded files include § 1215.3 for sizing equations; I could not locate the uploaded text for § 1215.4 and § 1215.5. If those sections contain additional CPC rules that apply to special cases, consult the full CPC volume or AHJ for the authoritative language. (I cannot quote what is not in the uploaded files.)

Common mistakes

Treating the pipe’s physical length as the only length — ignore fittings. Wrong. Always use the equivalent length (pipe + equivalent length allowances for fittings) per the methods in § 1215.1.
Sizing only for instantaneous demand of one appliance instead of the total connected demand (or failing to apply permitted diversity factors where allowed). The code bases sizing on the maximum hourly rating of appliances unless an approved diversity factor is used.
Using a table for the wrong gas type or wrong inlet/allowable pressure column (natural gas vs. propane have separate tables). Always use the correct table set in § 1215.2.
Forgetting minimum outlet size requirements (appliance outlet ≥ 1/2‑inch).

Worked example — how to apply the rule (procedure with numbers, conceptually)

Note: The CPC tables (Table 1215.2) with their numeric columns were not fully present in the uploaded snippets I was given. The steps below follow the CPC procedure; you must use the actual table pages in the CPC to read the numeric pipe‑size entries for your Q and L.

Scenario (given):

Fuel: Natural gas.
Appliances: Range (65,000 Btu/h), water heater (35,000 Btu/h), furnace (50,000 Btu/h). Total connected input = 150,000 Btu/h (convert to cubic feet per hour per local gas heating value if required).
From meter to most remote appliance developed run length: 75 feet of pipe (plus fittings equivalent). Equivalent length after adding fittings: 85 feet. (This is the number you use against the tables.)

Procedure:

Convert appliance inputs to the volumetric gas flow unit the table expects (Cubic feet per hour) using the local gas heating value (or use the CPC appliance‑flow lookup table for typical appliances if the exact input is unknown). The CPC includes appliance approximate inputs (see Table references).
Choose the correct table set in § 1215.2 for natural gas and the expected inlet pressure/allowable pressure drop for your installation.
In that table, select the column for the length equal to or greater than your equivalent length (here, the 85‑ft column or the next larger column). Move down that length column to find the row equal to or just exceeding your total gas demand (Q). The pipe size at the top of that row is the code table‑size for that section.
Repeat for each upstream section: when a branch adds more load you re‑compute the section demand and re‑read the table for the length of that section. Do sections in order from the most remote back toward the meter (Branch‑length method) or follow the Longest‑length method per § 1215.1.

Because the actual numeric rows/columns of Table 1215.2 were not present in the uploaded excerpts I can’t tell you the exact final diameter (I cannot invent the table numbers). Use the CPC Table 1215.2 on the code book pages to read the numeric size after following the steps above.

If you prefer using the equations (smooth wall tubing or engineer approach): use § 1215.3 — compute the required inside diameter (D) from Equation 1215.3(1)/(2) and Table 1215.3 using the same equivalent length L and the allowable ΔH (pressure drop) specified. The code directs this in § 1215.3.

Related provisions (CPC sections to check)

§ 1215.1 — Pipe sizing methods: Longest‑length, Branch‑length, Hybrid‑pressure.
§ 1215.2 — Pipe sizing tables (natural gas and propane tables).
§ 1215.3 — Sizing equations for smooth‑walled pipe/tubing; use Equation 1215.3(1)/(2) and Table 1215.3.
§ 1214.4 — Minimum piping outlet sizes for appliances (1/2‑in.; mobile home 3/4‑in.).
Fuel‑gas system sizing/pressure rules found elsewhere in the CPC and in the Mechanical Code (see CPU references for pressure‑drop and materials) — the CPC chapters quoted above cross‑reference NFPA54/UPC methods.

Code references

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

CPC § 1.11.0. Medium relevance — show source text

Pipe sizes recognized for this purpose are 2 inches, 2 [1] ⁄ 2 inches, 3 inches, 3 [1] ⁄ 2 inches, 4 inches, 4 [1] ⁄ 2 inches, 5 inches, 6 inches, etc. (50 mm, 65 mm, 80 mm, 90 mm, 100 mm, 115 mm, 125 mm, 150 mm, etc.). The tailpiece between the floor drain and its trap shall be 2 inches (50 mm) (or normal size) to ensure that the amount of wastewater entering the trap partially fills the waste branch. A 3 inch (80 mm) floor drain would thus require a 4 inch (100 mm) trap, and a 4 inch (100 mm) floor drain would require a 5 inch (125 mm) trap for the reasons previously stated.

WHERE IN DOUBT, CHECK WITH YOUR LOCAL Authority Having Jurisdiction.

2025 CALIFORNIA PLUMBING CODE 383

384 2025 CALIFORNIA PLUMBING CODE

CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE

APPENDIX C - ALTERNATE PLUMBING SYSTEMS

(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)
Adopt only those sections that are listed below
Chapter/Section

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 385

CPC § 1323.13.3 Medium relevance — show source text
2, 1323.13.3| |1326.4 - 1326.10|1326.5 - 1326.11| |1505.6 - 1505.14|1505.5 - 1505.13| |Figure 1505.10|Figure 1505.9| |1506.6 - 1506.13|1506.5 - 1506.12| |1603.3 - 1603.4|1603.4 - 1603.5| |Table 1603.4|Table 1603.5| |1603.5 - 1603.19|1603.6 - 1603.20| |1603.20|1503.2.4| |L 402.9 - L 402.11|L 402.8 - L 402.10| |L 404.9 - L 404.12|L 404.8 - L 404.11| |L 411.5, L 411.6|L 411.2, L411.3| |L 411.7|L 411.4| |L 411.9 - L 411.12|L 411.5 - L 411.8|

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RELATED PUBLICATIONS AND SERVICES

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Free Code Question: 800-201-0335

Uniform Plumbing Code – 2024 Edition:

The Uniform Plumbing Code is the most widely adopted plumbing code in the world. The 2024 edition contains complete “turnkey” requirements for the installation and maintenance of plumbing systems, all in one easy to use book.

Uniform Plumbing Code Illustrated Training Manual:

The UPC Illustrated Training Manual is an excellent reference for anyone involved in the plumbing industry. It contains an extensive definitions section and several hundred comprehensive technical diagrams and illustrations. It serves as a textbook, and it also is useful as a valuable tool for explaining the intent and use of the Code.

Uniform Plumbing Code Study Guide:

This book is the perfect complement to the UPC Illustrated Training Manual. Alone, it constitutes a complete self-study course for learning the UPC. It has hundreds of questions, general practice exams, and plumbing math, pipe sizing exercises and fitting identification. A big help in getting you ready for a certification exam!

Guide to Important Code Questions to the Uniform Plumbing Code:

An excellent reference for learning and understanding plumbing code changes and identifies code changes between editions. It is a useful tool for preparing code change proposals.

Uniform Mechanical Code – 2024 Edition:

The Uniform Mechanical Code contains complete requirements for the installation and maintenance of heating, ventilating, cooking and refrigeration systems.

Uniform Mechanical Code Illustrated Training Manual:

Contains technical diagrams and illustrations that demonstrate the intent and use of the UMC. A great reference for everyone involved in Mechanical HVACR design and installation.

Uniform Mechanical Code Study Guide:
CPC § 2025 Medium relevance — show source text
Gas Piping| |13|Health Care Facilities and Medical Gas and Medical Vacuum Systems| |14|Firestop Protection| |15|Alternate Water Sources for Nonpotable Applications| |16|Nonpotable Rainwater Catchment Systems| |17|Referenced Standards| |Appendix A|Recommended Rules for Sizing the Water Supply System| |Appendix B|Explanatory Notes on Combination Waste and Vent Systems| |Appendix C|Alternate Plumbing Systems| |Appendix D|Sizing Storm Water Drainage Systems| |Appendix E|Manufactured/Mobile Home Parks and Recreational Vehicle Parks| |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 Ventilation Opening Design| |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 Scalding and Legionella Growth| |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|

2025 CALIFORNIA PLUMBING CODE xiii

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FORMAT OF THE UNIFORM PLUMBING CODE

The following is a summary of the scope and intent of the provisions addressed within the chapters and appendices of the Uniform Plumbing Code :

Chapter 1 Administration.

Chapter 1 regulates the application, enforcement, and administration of subsequent requirements of the code. As well as establishing the scope of the code, this chapter is concerned with enforcing the requirements contained in the body of the code. A plumbing code, as with any other code, is intended to be adopted as a legally enforceable document to safeguard health, safety, property, and public welfare. The code cannot be effective without satisfactory provisions for its administration and enforcement. The Authority Having Jurisdiction is to review the proposed and completed work and to decide whether a plumbing system conforms to the code requirements. As a public servant, the Authority Having Jurisdiction enforces the code in an unbiased, proper manner. The design professional is responsible for the design of a safe plumbing system. The contractor is responsible for installing the system in accordance with the plans.

Chapter 2 Definitions.

To maintain consistency and encourage the use of common terminology, Chapter 2 establishes definitions to provide clarity of terms and promote the use of a common language throughout the code. Understanding definitions within the context of their application enables greater collaboration, efficiency, standardization, and interpretation in applying and enforcing terms used throughout the code. Codes are technical documents, and every term can impact the meaning of the code text. Terms not defined have a normally accepted meaning.

Chapter 3 General Regulations.

Chapter 3 regulates the general requirements, not specific to other chapters, for installing plumbing systems. Many regulations are not specific plumbing requirements but relate to the overall plumbing system. This chapter contains safety requirements for installing plumbing and also contains nonplumbing requirements for identifying pipes, pipe fittings, traps, fixtures, materials, and devices used in plumbing systems.
CPC § 309.0 Medium relevance — show source text
2025 CALIFORNIA PLUMBING CODE 469

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IS 33

Uniform Plumbing Code References for Ductile Iron and PVC Pressure Building Supply and Exterior Cold-Water Piping

The following sections of the 2024 Uniform Plumbing Code apply to ductile iron and PVC pressure building supply and exterior cold-water piping.

Chapter 3 General Regulations

309.0 Workmanship

312.0 Protection of Piping, Materials, and Struc tures

313.0 Hangers, Supports, and Anchors

314.0 Trenching, Excavation, and Backfill

Chapter 6 Water Supply and Distribution

604.0 Materials (water piping)

Table 604.1 Materials for Building Supply and Water Distribution Piping and Fittings

605.4 Ductile Iron Pipe and Joints

605.12 PVC Plastic Pipe and Joints

605.16.2 Plastic Pipe to Other Materials

609.0 Installation, Testing, Unions, and Location

Abbreviations

IAPMO International Association of Plumbing and Mechanical Officials

UPC Uniform Plumbing Code published by IAPMO

AWWA American Water Works Association

CSA Canadian Standards Association

Applicable Standards.

ASME B16.4 Gray Iron Threaded Fittings Classes 125 and 250

ASTM D1785 Poly (Vinyl Chloride) (PVC) Plastic Pipe, Schedules 40, 80, and 120

ASTM D2241 Poly (Vinyl Chloride) (PVC) Pressure-Rated Pipe (SDR Series)

ASTM D2466 Poly (Vinyl Chloride) (PVC) Plastic Pipe Fittings, Schedule 40

ASTM D2467 Poly (Vinyl Chloride) (PVC) Plastic Pipe Fittings, Schedule 80

ASTM F1970 Special Engineered Fittings, Appurtenances or Valves for use in Poly (Vinyl Chloride) (PVC) or Chlorinated Poly (Vinyl Chloride) (CPVC) Systems

AWWA C110 Ductile Iron and Gray-Iron Fittings

AWWA C111 Rubber-Gasket Joints for Ductile-Iron Pressure Pipe and Fittings

AWWA C151 Ductile-Iron Pipe, Centrifugally Cast

AWWA C153 Ductile-Iron Compact Fitting

AWWA C900 Polyvinyl Chloride (PVC) Pressure Pipe and Fabricated Fittings, 4 in. through 12 in. (100 mm through 300 mm)

AWWA C904 Crosslinked Polyethylene (PEX) Pressure Tubing, ½ in. through 3 In. (13 mm through 76 mm), for Water Service

AWWA C907 Injection-Molded Polyvinyl Chloride (PVC) Pressure Fittings, 4 In, through 12 in (100 mm through 300 mm) for Water, Wastewater and Reclaimed Water Service

IAPMO/

ANSI UPC-1 Uniform Plumbing Code

470 2025 CALIFORNIA PLUMBING CODE

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CPC § 101.2.2 Medium relevance — show source text
CFC—25: California Fire Code

101.2.2, 101.4.2, 301.3.1, 302.2, 307.1, 308.1, 802.2.1, 802.2.3, 803.2.3, 803.4.1.1, 803.4.1.2, 803.4.1.3, 803.4.1.4, 803.4.1.5, 803.4.1.6, Table 804.5.1.1(1), 904.1.5, 1011.6.1.1, 1303.1.2, 1305.2.8.1, 1305.2.14, 1305.2.14.1, 1401.2, 1501.1, 1501.5, 1502.1, 1502.1.1, 1502.2, 1502.3, 1504.1, 1507.1, 1507.2

CMC—25: California Mechanical Code

302.2, 702.7, 807.1, 902.1.1, 1008.1, 1305.2.7.1, 1305.2.8, 1305.2.8.1

CPC—25: California Plumbing Code

302.2, 408.1, 702.7, 1009.1, 1009.2, 1009.3, 1009.5, 1302.1.6, 1503.1

16-4 2025 CALIFORNIA EXISTING BUILDING CODE

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

REFERENCED STANDARDS

CRC—25: California Residential Code

101.2, 101.4.1, 104.3.1, 109.3.3, 109.3.10, 302.2, 307.1, 308.1, 401.3, 402.1, 405.2.6, 502.2, 502.3, 502.4, 503.2, 503.3, 503.11, 505.2, 505.3, 507.3, 701.3, 702.4, 702.5, 706.2, 708.1, 805.2, 806.4, 809.1, 906.2, 907.1, 1011.2.1, 1103.1, 1103.2, 1103.3, 1104.1, 1201.4, 1302.1.2, 1302.1.3, 1302.1.3, 1303.1.3, 1401.2, 1402.1, 1402.2, 1402.2.1, 1402.3, 1402.4, 1402.5, 1402.6

ICC 300—2023: ICC Standard on Bleachers, Folding and Telescopic Seating and Grandstands

301.1.1, 401.1.1, 1401.1.1

ICC A117.1—2017: Accessible and Usable Buildings and Facilities

CPC § 705.10 Medium relevance — show source text

Waste,
and Vent (DWV), Sewer, Sanitary, and Storm Plumbing Sys-
tems for Above and Below Ground Use|Joints|705.10|

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REFERENCED STANDARDS

TABLE 1701.1 (continued) REFERENCED STANDARDS

STANDARD NUMBER	STANDARD TITLE	APPLICATION	REFERENCED SECTION
ASTM C1540-2020	Standard Specification for Heavy-Duty Shielded Couplings Joining Hubless Cast Iron Soil Pipe and Fittings	Joints	705.2.2
ASTM C1563-2008 (R2021)	Standard Test Method for Gaskets for Use in Connection with Hub and Spigot Cast Iron Soil Pipe and Fittings for Sanitary Drain, Waste, Vent, and Storm Piping Applications	Joints	705.2.2
ASTM C1822-2021	Standard Specification for Insulating Covers on Accessible Lavatory Piping	Miscellaneous	403.3
ASTM D1253-2014	Standard Test Method for Residual Chlorine in Water	Miscellaneous	1506.10.6, 1603.4.1
ASTM D1785-2021a	Standard Specification for Poly (Vinyl Chloride) (PVC) Plastic Pipe, Schedules 40, 80, and 120	Piping	Table 604.1, Table 701.2
ASTM D2235-2021	Standard Specification for Solvent Cement for Acrylonitrile- Butadiene-Styrene (ABS) Plastic Pipe and Fittings	Joints	705.1.2
ASTM D2239-2021	Standard Specification for Polyethylene (PE) Plastic Pipe (SIDR-PR) Based on Controlled Inside Diameter	Piping	Table 604.1
ASTM D2241-2020	Standard Specification for Poly (Vinyl Chloride) (PVC) Pressure- Rated Pipe (SDR Series)	Piping	Table 604.1
ASTM D2464-2015	Standard Specification for Threaded Poly (Vinyl Chloride) (PVC) Plastic Pipe Fittings, Schedule 80	Fittings	Table 604.1
ASTM D2466-2021	Standard Specification for Poly (Vinyl Chloride) (PVC) Plastic Pipe Fittings, Schedule 40	Fittings	Table 604.1
ASTM D2467-2020	Standard Specification for Poly (Vinyl Chloride) (PVC) Plastic Pipe Fittings, Schedule 80	Fittings	Table 604.1
ASTM D2513-2020	Standard Specification for Polyethylene (PE) Gas Pressure Pipe, Tubing, and Fittings	Piping	1208.5.4, 1208.5.6.2, 1208.5.10.2, 1210.1.7.1(1)
ASTM D2564-2020	Standard Specification for Solvent Cements for Poly (Vinyl Chloride) (PVC) Plastic Piping Systems	Joints	605.12.2, 705.6.

CPC § 31-2022 Medium relevance — show source text
2025 CALIFORNIA PLUMBING CODE 453

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454 2025 CALIFORNIA PLUMBING CODE

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"The information contained in this appendix is not part of this American National Standard (ANS) and has not been processed in accordance with ANSI's requirements for an ANS. As such, this appendix may contain material that has not been subjected to public review or a consensus process. In addition, it does not contain requirements necessary for conformance to the standard."

The following IAPMO Installation Standard is included here for the convenience of the users of the Uniform Plumbing Code. It is not considered as a part of the Uniform Plumbing Code unless formally adopted as such. This Installation Standard is an independent, stand-alone document published by the International Association of Plumbing and Mechanical Officials and is printed herein by the expressed written permission of IAPMO.

INSTALLATION STANDARD FOR PEX TUBING SYSTEMS

FOR HOT- AND COLD-WATER DISTRIBUTION

IAPMO IS 31-2022

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

1 Scope

1.1 General

1.1.1 This Standard specifies requirements for the installation of SDR 9 CTS crosslinked polyethylene (PEX) tubing and fittings, including cold-expansion, crimp, press, and mechanical compression fittings, intended for hot- and cold-water distribution systems within buildings.

1.1.2 This Standards applies to

(a) SDR 9 CTS PEX tubing complying with ASTM F876 and pressure-rated in accordance with PPI TR-3; and (b) PEX fitting systems complying with (i) ASTM F877, for mechanical compression fittings and metal or plastic insert fittings with stainless steel press sleeves; (ii) ASTM F1807 or ASTM F2159, for metal or plastic insert fittings with copper crimp rings; (iii) ASTM F1960, for cold expansion fittings with PEX reinforced rings; or (iv) ASTM F2080, for cold expansion fittings with metal compression sleeves. 1.2 Terminology

In this Standard,

(a) “shall” is used to express a requirement, i.e., a provision that the user is obliged to satisfy to comply with the Standard; (b) “should” is used to express a recommendation, but not a requirement; (c) “may” is used to express an option or something permissible within the scope of the Standard; and (d) “can” is used to express a possibility or a capability. Notes accompanying sections of the Standard do not specify requirements or alternative requirements; their purpose is to separate explanatory or informa

tive material from the text. Notes to tables and figures are considered part of the table or figure and can be written as requirements.

1.3 Units of Measurement

SI units are the primary units of record in global commerce. In this Standard, the inch/pound units are shown in parentheses. The values stated in each measurement system are equivalent in application, but each unit system is to be used independently. All references to gallons are to U.S. gallons.

2 Reference Publications

CPC § 510.2 Medium relevance — show source text

432 2025 CALIFORNIA PLUMBING CODE

APPENDIX G

510.2(1) is 210 000 Btu/h (62 kW), and after reducing by 20 percent is 168 000 Btu/h (49.2 kW). Therefore, a 5 inch (127 mm) corrugated metal liner should be used in this example.

Single Wall Connectors. Once it has been established that relining the chimney is necessary, Type B double-wall vent connectors are not specifically required. This example could be redone using Table 510.2(2) for single-wall vent connectors. For this case, the vent connector and liner diameters would be the same as found for Type B double-wall connectors. [NFPA 54:F.2.4]

2025 CALIFORNIA PLUMBING CODE 433

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CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE

APPENDIX H - PRIVATE SEWAGE DISPOSAL SYSTEMS

(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	X			X	X
Adopt Entire Chapter as amended (amended sections listed below)
Adopt only those sections that are listed below
Chapter/Section

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CPC § 104.1 Medium relevance — show source text

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APPENDIX D

Col1	TABLE D 104.1 DISCHARGE FROM RECTANGULAR SCUPPERS (gallons per minute)1, 2, 3, 4	Col3	Col4	Col5	Col6	Col7
WATER HEAD (inches)	WIDTH OF SCUPPER (inches)	WIDTH OF SCUPPER (inches)	WIDTH OF SCUPPER (inches)	WIDTH OF SCUPPER (inches)	WIDTH OF SCUPPER (inches)	WIDTH OF SCUPPER (inches)
WATER HEAD (inches)	6	12	18	24	30	36
1⁄2	6	13	19	25	32	38
1	17	35	53	71	89	107
11⁄2	31	64	97	130	163	196
2	–	98	149	200	251	302
21⁄2	–	136	207	278	349	420
3	–	177	271	364	458	551
31⁄2	–	–	339	457	575	693
4	–	–	412	556	700	844

For SI units: 1 inch = 25.4 mm, 1 gallon per minute = 0.06 L/s

Notes: 1 Table D 104.1 is based on discharge over a rectangular weir with end contractions. 2 The head is the depth of water above the bottom of the scupper opening. 3 The height of the scupper opening shall be not less than two times the design head. 4 Coordinate the allowable head of water with the structural design of the roof.

2025 CALIFORNIA PLUMBING CODE 403

404 2025 CALIFORNIA PLUMBING CODE

CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE

APPENDIX E - MANUFACTURED/MOBILE HOME PARKS AND RECREATIONAL VEHICLE PARKS

(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.)

California Plumbing Code Medium relevance — show source text

5
10
15
20|NA
NA
NA
NA
NA|NA
NA
NA
NA
NA|38
35
NA
NA
NA|NA
NA
NA
NA
NA|NA
NA
NA
NA
NA|73
67
59
NA
NA|NA
NA
NA
NA
NA|NA
NA
NA
NA
NA|123
115
105
95
80|NA
NA
NA
NA
NA|NA
NA
NA
NA
NA|200
183
170
156
144|163
NA
NA
NA
NA|520
NA
NA
NA
NA|273
252
235
217
202| |30|2
5
10
15
20
30|NA
NA
NA
NA
NA
NA|NA
NA
NA
NA
NA
NA|41
NA
NA
NA
NA
NA|NA
NA
NA
NA
NA
NA|NA
NA
NA
NA
NA
NA|81
75
66
NA
NA
NA|NA
NA
NA
NA
NA
NA|NA
NA
NA
NA
NA
NA|136
127
113
105
88
NA|NA
NA
NA
NA
NA
NA|NA
NA
NA
NA
NA
NA|215
196
182
168
155
NA|158
NA
NA
NA
NA
NA|578
NA
NA
NA
NA
NA|302
279
260
240
223
182| |50|2
5
10
15
20
30|NA
NA
NA
NA
NA
NA|NA
NA
NA
NA
NA
NA|NA
NA
NA
NA
NA
NA|NA
NA
NA
NA
NA
NA|NA
NA
NA
NA
NA
NA|91
NA
NA
NA
NA
NA|NA
NA
NA
NA
NA
NA|NA
NA
NA
NA
NA
NA|160
149
136
124
NA
NA|NA
NA
NA
NA
NA
NA|NA
NA
NA
NA
NA
NA|250
228
212
195
180
NA|NA
NA
NA
NA
NA
NA|NA
NA
NA
NA
NA
NA|350
321
301
278
258
NA| |Minimum
internal area of
chimney
(square inches)|Minimum
internal
CPC § 25.4 Medium relevance — show source text
(inch)| ||8|8|8|9|9|9|10|10|10| ||COMBINED APPLIANCE INPUT RATING IN THOUSANDS OF BTU PER HOUR|COMBINED APPLIANCE INPUT RATING IN THOUSANDS OF BTU PER HOUR|COMBINED APPLIANCE INPUT RATING IN THOUSANDS OF BTU PER HOUR|COMBINED APPLIANCE INPUT RATING IN THOUSANDS OF BTU PER HOUR|COMBINED APPLIANCE INPUT RATING IN THOUSANDS OF BTU PER HOUR|COMBINED APPLIANCE INPUT RATING IN THOUSANDS OF BTU PER HOUR|COMBINED APPLIANCE INPUT RATING IN THOUSANDS OF BTU PER HOUR|COMBINED APPLIANCE INPUT RATING IN THOUSANDS OF BTU PER HOUR|COMBINED APPLIANCE INPUT RATING IN THOUSANDS OF BTU PER HOUR| |VENT
HEIGHT
H
(feet)|FAN
+FAN**|FAN
+NAT|NAT
+NAT|FAN
+FAN|FAN
+NAT|NAT
+NAT|FAN
+FAN|FAN
+NAT|NAT
+NAT| |6
8
10
15
20
30
50
100|404
444
477
556
621
720
854
1025|314
348
377
444
499
585
706
873|260
290
315
365
405
470
550
625|547
602
649
753
842
979
1164
1408|434
480
522
612
688
808
977
1215|335
378
405
465
523
605
705
800|672
740
800
924
1035
1209
1451
1784|520
577
627
733
826
975
1188
1502|410
465
495
565
640
740
860
975|

For SI units: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1000 British thermal units per hour = 0.293 kW, 1 square inch = 0.000645 m [2]

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WATER HEATERS

TABLE 510.2(1) TYPE B DOUBLE-WALL VENT [NFPA 54: TABLE 13.2(a)] (continued)*

|Col1|Col2|Col3|Col4|Col5|NUMBER OF
CPC § 309.0 Medium relevance — show source text
WORKMANSHIP . . . . . . . . . . . . . . . .309.0, 609.1, 1208.5.7

WRAPPING OF PIPE . . . . . . . . . . . . . . . . . . . . . . . . .609.3,

1210.3, E 403.6

WROUGHT IRON

(GALVANIZED) . . . . . . . . . .402.6.1, Table 604.1, 604.6,

604.7, 701.2, 707.1, 1101.4,

1208.5.2.2, 1208.5.9.5,

E 403.5

WYE CONNECTIONS . . . . . . . . . . . . . . . . . . . 414.3, 419.2,

706.2 – 706.4,

707.5, 707.6,

710.4, 719.4, 907.2,

909.1, 1101.16.2

– X –

X-RAY DARKROOMS . . . . . . . . . . . . . . . . . . . . . . . . . .811.8

– Y –

YOKE VENTS . . . . . . . . . . . . . . . . . . . . . . . . . . .227.0, 907.0

– Z –

ZINC ALLOY COMPONENTS . . . . . . . . . .406.4, 1208.5.9.5

2025 CALIFORNIA PLUMBING CODE 587

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HISTORY NOTE APPENDIX

2025 CALIFORNIA PLUMBING CODE CALIFORNIA CODE OF REGULATIONS, TITLE 24, PART 5

HISTORY:

For prior code history, see the History Note Appendix to the California Plumbing Code, 2022 Triennial Edition, effective January 1, 2023.

1. (BSC 02/24, DSA-SS 02/24, DSA-SS 01/24 CWoRE, DWR 01/24, HCD 03/24, OSHPD 02/24, SFM 02/24) Adoption by reference the 2024 Uniform Plumbing Code with necessary amendments to become the 2025 Cali- fornia Plumbing Code, and repeal of the 2021 edition of the Uniform Plumbing Code. Effective on January 1, 2026.

2025 CALIFORNIA PLUMBING CODE 589

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LICENSE AGREEMENT
CPC § 1315.3 High relevance — show source text
TABLE 1315.3

Cr AND Y FOR NATURAL GAS AND UNDILUTED

PROPANE AT STANDARD CONDITIONS

[NFPA 54: TABLE 6.4.2]

GAS FORMULA FACTORS Col3

GAS Cr Y

Natural Gas 0.6094 0.9992

Undiluted Propane 1.2462 0.9910

1315.4 Sizing of Piping Sections. To determine the size of each section of pipe in a system within the range of Table 1315.2(1) through Table 1315.2(36), proceed as follows:

(1) Measure the length of the pipe from the gas meter location to the most remote outlet on the system.

(2) Select the length in feet column and row showing the distance, or the next longer distance where the table does not give the exact length.

(3) Starting at the most remote outlet, find in the just selected the gas demand for that outlet. Where the exact figure of demand is not shown, choose the next larger figure in the

row.

(4) At the top of the column in the table will be found the correct size of pipe.

(5) Using this same row, proceed in a similar manner for each section of pipe serving this outlet. For each section of pipe, determine the total gas demand supplied by that section. Where gas piping sections serve both heating and cooling appliances and the installation prevents both units from operating simultaneously, the larger of the two demand loads needs to be used in sizing these sections.

(6) Size each section of branch piping not previously sized by measuring the distance from the gas meter location to the most remote outlet in that branch and follow the procedures of steps 2, 3, 4, and 5 above. Size branch piping in the order of their distance from the meter location, beginning with the most distant outlet not previously sized.

1315.5 Engineering Methods. For conditions other than those covered by Section 1315.1, such as longer runs or greater gas demands, the size of each gas piping system shall be determined by standard engineering methods acceptable to the Authority Having Jurisdiction, and each such system shall be so designed that the total pressure drop between the meter or other point of supply and an outlet where full demand is being supplied to outlets, shall be in accordance with the requirements of Section 1308.3.

1315.6 Variable Gas Pressures. Where the supply gas pressure exceeds 5 psi (34 kPa) for natural gas and 10 psi (69 kPa) for undiluted propane or is less than 6 inches (1.5 kPa) of water column, or where diversity demand factors are used, the design, pipe, sizing, materials, location, and use of such systems first shall be approved by the Authority Having Jurisdiction. Piping systems designed for pressures exceeding the serving gas supplier’s standard delivery pressure shall have prior verification from the gas supplier of the availability of the design pressure.

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FUEL GAS PIPING
CPC § 1314.2 High relevance — show source text
Where gas of a different specific gravity is to be delivered, the serving gas supplier shall be permitted to be contacted for specific gravity conversion factors to use in sizing piping systems from the pipe sizing tables in this chapter. 1314.2 Volume. The hourly volume of gas required at each piping outlet shall be taken as not less than the maximum hourly rating as specified by the manufacturer of the appliance or appliances to be connected to each such outlet.

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FUEL GAS PIPING

1314.3 Gas Appliances. Where the gas appliances to be installed have not been definitely specified, Table 1308.3.1 shall be permitted to be used as a reference to estimate requirements of typical appliances. To obtain the cubic feet per hour (m [3] /h) of gas required, divide the input of the appliances by the average Btu (kW•h) heating value per cubic foot (m [3] ) of the gas. The average Btu (kW•h) per cubic foot (m [3] ) of the gas in the area of the installation shall be permitted to be obtained from the serving gas supplier. 1314.4 Size of Piping Outlets. The size of the supply piping outlet for a gas appliance shall be not less than [1] ⁄ 2 of an inch (15 mm). The size of a piping outlet for a mobile home shall be not less than [3] ⁄ 4 of an inch (20 mm).

1315.0 Required Gas Piping Size. 1315.1 Pipe Sizing Methods. Where the pipe size is to be determined using any of the methods in Section 1315.1.1 through Section 1315.1.3, the diameter of each pipe segment shall be obtained from the pipe sizing tables in Section 1315.2 or from the sizing equations in Section 1315.3. [NFPA 54:6.1] 1315.1.1 Longest Length Method. The pipe size of each section of gas piping shall be determined using the longest length of piping from the point of delivery to the most remote outlet and the load of the section. [NFPA 54:6.1.1] 1315.1.2 Branch Length Method. Pipe shall be sized as follows:

(1) Pipe size of each section of the longest pipe run from the point of delivery to the most remote outlet shall be determined using the longest run of piping and the load of the section.

(2) The pipe size of each section of branch piping not previously sized shall be determined using the length of piping from the point of delivery to the most remote outlet in each branch and the load of the section. [NFPA 54:6.1.2] 1315.1.3 Hybrid Pressure. The pipe size for each section of higher pressure gas piping shall be determined using the longest length of piping from the point of delivery to the most remote line pressure regulator. The pipe size from the line pressure regulator to each outlet shall be determined using the length of piping from the regulator to the most remote outlet served by the regulator. [NFPA 54:6.1.3] **1315.2 Sizing of Gas Piping Systems.
CPC § 1215.1.2 High relevance — show source text
1215.1.2 Branch Length Method. Pipe shall be sized as follows:

(1) Pipe size of each section of the longest pipe run from the point of delivery to the most remote outlet shall be determined using the longest run of piping and the load of the section.

(2) The pipe size of each section of branch piping not previously sized shall be determined using the length of piping from the point of delivery to the most remote outlet in each branch and the load of the section. [NFPA 54:6.1.2]

1215.1.3 Hybrid Pressure. The pipe size for each section of higher pressure gas piping shall be determined using the longest length of piping from the point of delivery to the most remote line pressure regulator. The pipe size from the line pressure regulator to each outlet shall be determined using the length of piping from the regulator to the most remote outlet served by the regulator.

[NFPA 54:6.1.3] 1215.2 Sizing of Gas Piping Systems. Sizing of piping systems shall be in accordance with Section 1215.2.1 for natural gas piping systems and Section 1215.2.2 for propane piping systems. 1215.2.1 Natural Gas Piping Systems. Table 1215.2(1) through Table 1215.2(23) shall be used in conjunction with one of the methods described in Section 1215.1.1 through Section 1215.1.3 for piping materials other than non-corrugated stainless steel tubing. Section 1215.3 shall be used in conjunction with one of the methods described in Section 1215.1.1 through Section 1215.1.3 for non-corrugated stainless steel tubing.

[NFPA 54:6.2.1, 6.2.2] 1215.2.2 Propane Piping Systems. Table 1215.2(24) through Table 1215.2(36) shall be used in conjunction with one of the methods described in Section 1215.1.1 through Section 1215.1.3 for piping materials other than non-corrugated stainless steel tubing. Section 1215.3 shall be used in conjunction with one of the methods described in Section 1215.1.1 through Section 1215.1.3 for non-corrugated stainless steel tubing.

[NFPA 54:6.3.1, 6.3.2] 1215.3 Sizing Equations. The inside diameter of smooth wall pipe or tubing shall be determined by Equation 1215.3(1), Equation 1215.3(2) and Table 1215.3 using the equivalent pipe length determined by the methods in Section 1215.1.1 through Section 1215.1.3. [NFPA 54:6.4]

LOW-PRESSURE GAS FORMULA (LESS THAN 1.5 psi)

[NFPA 54:6.4.1]

[Equation 1215.3(1)]

Q [0.381] D =

0.206

19.17 [(]

Δ H )

Cr x L

Where:

D = inside diameter of pipe, inches

Q = input rate appliance(s), cubic feet per hour at 60 ˚ F and 30 inch mercury column

L = equivalent length of pipe, feet
CPC § 6.1.2 High relevance — show source text
(1) Pipe size of each section of the longest pipe run from the point of delivery to the most remote outlet shall be determined using the longest run of piping and the load of the section.

(2) The pipe size of each section of branch piping not previously sized shall be determined using the length of piping from the point of delivery to the most remote outlet in each branch and the load of the section. [NFPA 54:6.1.2] 1315.1.3 Hybrid Pressure. The pipe size for each section of higher pressure gas piping shall be determined using the longest length of piping from the point of delivery to the most remote line pressure regulator. The pipe size from the line pressure regulator to each outlet shall be determined using the length of piping from the regulator to the most remote outlet served by the regulator. [NFPA 54:6.1.3] 1315.2 Sizing of Gas Piping Systems. Sizing of piping systems shall be in accordance with Section 1315.2.1 for natural gas piping systems and Section 1315.2.2 for propane piping systems. 1315.2.1 Natural Gas Piping Systems. Table 1315.2(1) through Table 1315.2(23) shall be used in conjunction with one of the methods described in Section 1315.1.1 through Section 1315.1.3 for piping materials other than non-corrugated stainless steel tubing. Section 1315.3 shall be used in conjunction with one of the methods described in Section 1315.1.1 through Section 1315.1.3 for non-corrugated stainless steel tubing. [NFPA 54:6.2.1, 6.2.2]

1315.2.2 Propane Piping Systems. Table 1315.2(24) through Table 1315.2(36) shall be used in conjunction with one of the methods described in Section 1315.1.1 through Section 1315.1.3 for piping materials other than non-corrugated stainless steel tubing. Section 1315.3 shall be used in conjunction with one of the methods described in Section 1315.1.1 through Section 1315.1.3 for non-corrugated stainless steel tubing. [NFPA 54:6.3.1, 6.3.2] 1315.3 Sizing Equations. The inside diameter of smooth wall pipe or tubing shall be determined by Equation 1315.3(1), Equation 1315.3(2) and Table 1315.3 using the equivalent pipe length determined by the methods in Section 1315.1.1 through Section 1315.1.3. [NFPA 54:6.4]

LOW-PRESSURE GAS FORMULA [LESS THAN 1.5 psi (10.3 kPa)]

[NFPA 54:6.4.1]

[Equation 1315.3(1)]

Q [0.381] D =

Δ H 0.206

19.17 ( Cr x L )

Where:

D = inside diameter of pipe, inches Q = input rate appliance(s), cubic feet per hour at 60°F and 30 inch mercury column L = equivalent length of pipe, feet Δ H = pressure drop, inches of water column

Cr = in accordance with Table 1315.3
CPC § 610.6 High relevance — show source text
610.6 Friction and Pressure Loss. Except where the type of pipe used and the water characteristics are such that no decrease in capacity due to the length of service (age of system) is expected, friction-loss data shall be obtained from the “Fairly Rough” or “Rough” charts in Appendix A of this code. Friction or pressure losses in a water meter, valve, and fittings shall be obtained from the same sources. Pressure losses through water-treating equipment, backflow prevention devices, or other flow-restricting devices shall be computed in accordance with Section 610.2. 610.7 Conditions for Using Table 610.4. On a proposed water piping installation sized using Table 610.4, the following conditions shall be determined:

(1) Total number of fixture units as determined from Table 610.3, Equivalent Fixture Units, for the fixtures to be installed.

(2) Developed length of supply pipe from meter to the most remote outlet.

(3) Difference in elevation between the meter or other source of supply and the highest fixture or outlet.

(4) Pressure in the street main or another source of supply at the locality where the installation is to be made.

(5) In localities where there is a fluctuation of pressure in the main throughout the day, the water piping system shall be designed on the basis of the minimum pressure available. 610.8 Size of Meter and Building Supply Pipe Using Table 610.4. The size of the meter and the building supply pipe shall be determined as follows:

(1) Determine the available pressure at the water meter or other source of supply.

(2) Add or subtract depending on positive or negative elevation change, [1] ⁄ 2 psi (3.4 kPa) for each foot (305 mm) of difference in elevation between such source of supply and the highest water supply outlet in the building or on the premises.

(3) Use the “pressure range” group within which this pressure will fall using Table 610.4.

(4) Select the “length” column that is equal to or longer than the required length.

(5) Follow down the column to a fixture unit value equal to or exceeding the total number of fixture units required by the installation.

(6) Having located the proper fixture unit value for the required length, sizes of meter and building supply pipe as found in the two left-hand columns shall be applied.

No building supply pipe shall be less than [3] ⁄ 4 of an inch (20 mm) in diameter.

610.9 Size of Branches. Where Table 610.4 is used, the minimum size of each branch shall be determined by the total fixture units served by that branch and then following the steps in Section 610.8. No branch piping shall exceed the total demand in fixture units for the system computed from Table 610.3.

610.10 Sizing for Flushometer Valves. Where using Table 610.4 to size water supply systems serving flushometer valves, the number of flushometer fixture units assigned to every section of pipe, whether branch or main, shall be determined by the number and category of flushometer valves served by that section of pipe, in accordance with Table 610.10. Piping supplying a flushometer valve shall be not less in size than the valve inlet.

Where using Table 610.10 to size water piping, care shall be exercised to assign flushometer fixture units based on the number and category of fixtures served.

|TABLE 610.

GAS	FORMULA FACTORS	Col3
GAS	Cr	Y
Natural Gas	0.6094	0.9992
Undiluted Propane	1.2462	0.9910

CPC § 610.4. High relevance — show source text

(3) Use the “pressure range” group within which this pressure will fall using Table 610.4.

(4) Select the “length” column that is equal to or longer than the required length.

(5) Follow down the column to a fixture unit value equal to or exceeding the total number of fixture units required by the installation.

(6) Having located the proper fixture unit value for the required length, sizes of meter and building supply pipe as found in the two left-hand columns shall be applied.

No building supply pipe shall be less than [3] ⁄ 4 of an inch (20 mm) in diameter.

610.9 Size of Branches. Where Table 610.4 is used, the minimum size of each branch shall be determined by the total fixture units served by that branch and then following the steps in Section 610.8. No branch piping shall exceed the total demand in fixture units for the system computed from Table 610.3.

610.10 Sizing for Flushometer Valves. Where using Table 610.4 to size water supply systems serving flushometer valves, the number of flushometer fixture units assigned to every section of pipe, whether branch or main, shall be determined by the number and category of flushometer valves served by that section of pipe, in accordance with Table 610.10. Piping supplying a flushometer valve shall be not less in size than the valve inlet.

Where using Table 610.10 to size water piping, care shall be exercised to assign flushometer fixture units based on the number and category of fixtures served.

TABLE 610.10 FLUSHOMETER FIXTURE UNITS FOR WATER SIZING USING TABLE 610.3	Col2	Col3
FIXTURE CATEGORY: WATER CLOSET WITH FLUSHOMETER VALVES	FIXTURE CATEGORY: WATER CLOSET WITH FLUSHOMETER VALVES	FIXTURE CATEGORY: WATER CLOSET WITH FLUSHOMETER VALVES
NUMBER OF FLUSHOMETER VALVES	INDIVIDUAL FIXTURE UNITS ASSIGNED IN DECREASING VALUE	FIXTURE UNITS ASSIGNED FOR WATER CLOSETS AND SIMILAR 10-UNIT FIXTURES IN ACCUMULATIVE VALUES
1	40	40
2	30	70
3	20	90
4	15	105
5 or more	10 each	115 plus 10 for each additional fixture in excess of 5
FIXTURE CATEGORY: URINALS WITH FLUSHOMETER VALVES	FIXTURE CATEGORY: URINALS WITH FLUSHOMETER VALVES	FIXTURE CATEGORY: URINALS WITH FLUSHOMETER VALVES
NUMBER OF FLUSHOMETER VALVES	INDIVIDUAL FIXTURE UNITS ASSIGNED IN DECREASING VALUE	FIXTURE UNITS ASSIGNED FOR URINALS AND SIMILAR **5-UNIT FIXTURES

CPC § 5.3.2.3 High relevance — show source text
The total connected hourly load shall be used as the basis for piping sizing, assuming all appliances are operating at full capacity simultaneously. Exception: Sizing shall be permitted to be based upon established load diversity factors. [NFPA 54:5.3.2.3] 1308.3.2 Sizing Methods. Gas piping shall be sized in accordance with one of the following: (1) Pipe sizing tables or sizing equations in this chapter.

(2) Sizing tables included in a listed piping system manufacturer’s installation instructions.

(3) Engineering methods. [NFPA 54:5.3.3] 1308.3.3 Allowable Pressure Drop. The design pressure loss in a piping system from the point of delivery to the inlet connection of all appliances served shall be such that the supply pressure at each appliance inlet is greater than or equal to the minimum pressure required by the appliance. [NFPA 54:5.3.4] 1308.4 Acceptable Piping Materials and Joining Methods. Materials used for piping systems shall comply with the requirements of Section 1308.4.1 through Section 1308.4.4.2.3. {NFPA 54:5.5.1.1} 1308.4.1 Used Materials. Pipe, fittings, valves, or other materials shall not be used again unless they are free of foreign materials and have been ascertained to be adequate for the service intended. [NFPA 54:5.5.1.2] 1308.4.2 Metallic Pipe. Metallic pipe shall be in accordance with Section 1308.4.2.1 through Section 1308.4.2.4.

1308.4.2.1 Cast Iron. Cast-iron pipe shall not be used. [NFPA 54:5.5.2.1] 1308.4.2.2 Steel, Stainless Steel, and Wrought-Iron. Steel, stainless steel, and wroughtiron pipe shall be at least Schedule 40 and shall comply with the dimensional standards of ASME B36.10M and one of the following: (1) ASTM A53 (2) ASTM A106 (3) ASTM A312 {NFPA 54:5.5.2.2}

TABLE 1308.3.1

APPROXIMATE GAS INPUT FOR TYPICAL APPLIANCES

[NFPA 54: TABLE A.5.3.2.1]

«

«

«

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FUEL GAS PIPING

»

»

»

»

»

»

»

»

»

»

»

1308.4.3 Metallic Tubing. Tubing shall not be used with gases corrosive to the tubing material. [NFPA 54:5.5.3.1] 1308.4.3.1 Steel Tubing. Steel tubing shall comply with ASTM A254. [NFPA 54:5.5.3.2] **1308.4.3.2 Stainless Steel Tubing.
CPC § 29-1 Medium relevance — show source text
Using Equation 29-1, calculate the pressure available to offset friction loss in water-distribution piping between the service valve and the sprinklers.

Step 8—Determine the maximum allowable pipe length

Use Tables R309.3.6.2 (4) through R309.3.6.2 (9) to select a material and size for water distribution piping. The piping material and size shall be acceptable if the developed length of pipe between the service valve and the most remote sprinkler does not exceed the maximum allowable length specified by the applicable table. Interpolation of P t between the tabular values shall be permitted.

The maximum allowable length of piping in Tables R309.3.6.2 (4) through R309.3.6.2 (9) incorporates an adjustment for pipe fittings. Additional consideration of friction losses associated with pipe fittings shall not be required.

R309.3.7 Instructions and signs. An owner’s manual for the automatic sprinkler system shall be provided to the owner. A sign or valve tag shall be installed at the main shutoff valve to the water distribution system stating, “Warning, the water system for this home supplies fire sprinklers that require certain flows and pressures to fight a fire. Devices that restrict the flow or decrease the pressure or automatically shut off the water to the fire sprinkler system, such as water softeners, filtration systems and automatic shutoff valves, shall not be added to this system without a review of the fire sprinkler system by a fire protection specialist. Do not remove this sign.”

R309.3.8 Inspections. The water distribution system shall be inspected in accordance with Sections R309.3.8.1 and R309.3.8.2.

R309.3.8.1 Preconcealment inspection. The following items shall be verified prior to the concealment of any automatic sprinkler system piping:
1. Sprinklers are installed in all areas as required by Section R309.3.1.1.
2. Where sprinkler water spray patterns are obstructed by construction features, luminaires or ceiling fans, additional sprinklers are installed as required by Section R309.3.2.4.2.
3. Sprinklers are the correct temperature rating and are installed at or beyond the required separation distances from heat sources as required by Sections R309.3.2.1 and R309.3.2.2 .
4. The pipe size equals or exceeds the size used in applying Tables R309.3.6.2 (4) through R309.3.6.2 (9) or, if the piping system was hydraulically calculated in accordance with Section R309.3.6.1, the size used in the hydraulic calculation.
5. The pipe length does not exceed the length permitted by Tables R309.3.6.2 (4) through R309.3.6.2 (9) or, if the piping system was hydraulically calculated in accordance with Section R309.3.6.1, pipe lengths and fittings do not exceed those used in the hydraulic calculation.
2025 CALIFORNIA RESIDENTIAL CODE 3-53

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

BUILDING PLANNING
CPC § 609.4 Medium relevance — show source text
609.4 Testing . . . . . . . . . . . . . . . . . . . . .155

609.5 Unions . . . . . . . . . . . . . . . . . . . . .155

609.6 Location . . . . . . . . . . . . . . . . . . . .155

609.7 Abutting Lot . . . . . . . . . . . . . . . . .155

609.8 Pumps . . . . . . . . . . . . . . . . . . . . .155

609.9 Low-Pressure Cutoff Required on Booster Pumps for Water Distribution Systems . . . . . . . . . . .156

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TABLE OF CONTENTS

609.10 Disinfection of Potable Water System . . . . . . . . . . . . . . . . . . . . .156

609.11 Water Hammer . . . . . . . . . . . . . . .156

609.12 Pipe Insulation . . . . . . . . . . . . . . .156

610.0 Size of Potable Water Piping . . . .156

610.1 Size . . . . . . . . . . . . . . . . . . . . . . . .156

610.2 Pressure Loss . . . . . . . . . . . . . . . .156

610.3 Quantity of Water . . . . . . . . . . . . .157

610.4 Sizing Water Supply and Distribution Systems . . . . . . . . . . .157

610.5 Sizing per Appendices A, C, and M . . . . . . . . . . . . . . . . .157

610.6 Friction and Pressure Loss . . . . . .157

610.7 Conditions for Using Table 610.4 . . . . . . . . . . . . . . . . . .157

610.8 Size of Meter and Building Supply Pipe Using Table 610.4 . .157

610.9 Size of Branches . . . . . . . . . . . . .157

610.10 Sizing for Flushometer Valves . . .157

Table 610.10 Flushometer Fixture Units for Water Sizing Using Table 610.3 . . . . . . . . . . . . . . . . . .157

Table 610.3 Water Supply Fixture Units (WSFU) and Minimum Fixture Branch Pipe Sizes . . . . . . . . . . . .158

Table 610.4 Fixture Unit Table for

Determining Water Pipe and Meter Sizes . . . . . . . . . . . . . .159

610.11 Sizing Systems for Flushometer Tanks . . . . . . . . . . . .160

610.12 Sizing for Velocity . . . . . . . . . . . . .160

610.13 Exceptions . . . . . . . . . . . . . . . . . .160

611.0 Drinking Water Treatment Units . . . . . . . . . . . . . . . . . . . . . . .160

611.1 Application . . . . . . . . . . . . . . . . . .160
CPC § 5.5.2.4 Medium relevance — show source text
Threaded copper, copper alloy, or aluminum alloy pipe shall not be used with gases corrosive to such material. [NFPA 54:5.5.2.4]

1308.4.2.4 Aluminum Alloy Pipe. Aluminum alloy pipe shall comply with ASTM B241 (except that the use of alloy 5456 is prohibited), and shall be marked at each end of each length indicating compliance. Aluminum alloy pipe shall be coated to protect against external corrosion where it is in contact with masonry, plaster, or insulation or is subject to repeated wettings by such liquids as water, detergents, or sewage. [NFPA 54:5.5.2.5]

Aluminum alloy pipe shall not be used in exterior locations or underground. [NFPA 54:5.5.2.6]

»

»

»

»

»

»

»

ular supply shall be permitted to be used for this purpose.

[NFPA 54:5.2.2.1 – 5.2.2.2] 1308.3 Sizing of Gas Piping Systems. Gas piping systems shall be of such size and so installed as to provide a supply of gas sufficient to meet the maximum demand and supply gas to each appliance inlet at not less than the minimum supply pressure required by the appliance. [NFPA 54:5.3.1]

1308.3.1 Maximum Gas Demand. The volumetric flow rate of gas to be provided shall be the sum of the maximum input of the appliances served. The volumetric flow rate of gas to be provided shall be adjusted for altitude where the installation is above 2 000 feet (610 m). [NFPA 54:5.3.2.1 – 5.3.2.2] Where the input rating is not indicated, the gas supplier, appliance manufacturer, or a qualified agency shall be contacted or the rating from Table 1308.3.1 shall be used for estimating the volumetric flow rate of gas to be supplied. The total connected hourly load shall be used as the basis for piping sizing, assuming all appliances are operating at full capacity simultaneously. Exception: Sizing shall be permitted to be based upon established load diversity factors. [NFPA 54:5.3.2.3] 1308.3.2 Sizing Methods. Gas piping shall be sized in accordance with one of the following: (1) Pipe sizing tables or sizing equations in this chapter.

(2) Sizing tables included in a listed piping system manufacturer’s installation instructions.

(3) Engineering methods. [NFPA 54:5.3.3] 1308.3.3 Allowable Pressure Drop. The design pressure loss in a piping system from the point of delivery to the inlet connection of all appliances served shall be such that the supply pressure at each appliance inlet is greater than or equal to the minimum pressure required by the appliance. [NFPA 54:5.3.4] 1308.4 Acceptable Piping Materials and Joining Methods. Materials used for piping systems shall comply with the requirements of Section 1308.4.1 through Section 1308.4.4.2.3. {NFPA 54:5.5.1.1} 1308.4.1 Used Materials. Pipe, fittings, valves, or other materials shall not be used again unless they are free of foreign materials and have been ascertained to be adequate for the service intended.

CPC § 9-3 Medium relevance — show source text

Notes in reference to Table 9-3 and Table 9-4.

If termination bus-landing stubs are installed perpendicular to the back of the board, a wider enclosure dimension will be required to accommodate the installation of PG&E’s cables.
Maintain a clear working space. When return flanges are necessary, ensure they do not intrude into service-conductor space.
Dimension W is the minimum width of the pull section access opening.
The minimum termination height is 40-1/4 inches for bottom-fed service sections only as shown in

Section 7, Figure 7-7 on Page 7-8 and Section 10, Figure 10-16 on Page 10-27.

The X-dimension is measured from the bottom of the enclosure to the first phase bolt.

9-13 2022 – 2023

Section 9, Electric Metering: Components and Cable Terminating Facilities

9.10. (continued)

Col1	Col2	3/4” Min.	Col4

Connectors Over 200 Amp Furnished by PG&E

2”

Y 4” Min. Wall−Mou ts 1” Min. Connect Furnishe 2-1/2” Min.	Col2	Col3	Col4	4” Min. Wall−Mou 1” Min. Connect Furnishe 2-1/2” Min.
1” Min. 2-1/2” Min. ts Connect Furnishe Y 4” Min. Wall−Mou	Y	Y	Y	Y
1” Min. 2-1/2” Min. ts Connect Furnishe Y 4” Min. Wall−Mou
1” Min. 2-1/2” Min. ts Connect Furnishe Y 4” Min. Wall−Mou

Conduit Must Be Staggered to Facilitate Service Cable Installation

W Y

Customer Service Entrance Conductors Exit Above Bus Stubs

1/2” Bolts

Shaded Space is for Service Supply Conductors Only

1” Min.–Wall−Mounted 4” Min.–Pad−Mounted

See Note 2

Lateral Conduits

CPC § 1215.0 Medium relevance — show source text
The size of a piping outlet for a mobile home shall be not less than [3] ⁄ 4 of an inch in diameter (20 mm).

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FUEL GAS PIPING

1215.0 Required Gas Piping Size. 1215.1 Pipe Sizing Methods. Where the pipe size is to be determined using any of the methods in Section 1215.1.1 through Section 1215.1.3, the diameter of each pipe segment shall be obtained from the pipe sizing tables in Section 1215.2 or from the sizing equations in Section 1215.3. [NFPA 54:6.1]

1215.1.1 Longest Length Method. The pipe size of each section of gas piping shall be determined using the longest length of piping from the point of delivery to the most remote outlet and the load of the section. [NFPA 54:6.1.1] (see calculation example in Figure 1215.1.1)

1215.1.2 Branch Length Method. Pipe shall be sized as follows:

(1) Pipe size of each section of the longest pipe run from the point of delivery to the most remote outlet shall be determined using the longest run of piping and the load of the section.

(2) The pipe size of each section of branch piping not previously sized shall be determined using the length of piping from the point of delivery to the most remote outlet in each branch and the load of the section. [NFPA 54:6.1.2]

1215.1.3 Hybrid Pressure. The pipe size for each section of higher pressure gas piping shall be determined using the longest length of piping from the point of delivery to the most remote line pressure regulator. The pipe size from the line pressure regulator to each outlet shall be determined using the length of piping from the regulator to the most remote outlet served by the regulator.

[NFPA 54:6.1.3] 1215.2 Sizing of Gas Piping Systems. Sizing of piping systems shall be in accordance with Section 1215.2.1 for natural gas piping systems and Section 1215.2.2 for propane piping systems. 1215.2.1 Natural Gas Piping Systems. Table 1215.2(1) through Table 1215.2(23) shall be used in conjunction with one of the methods described in Section 1215.1.1 through Section 1215.1.3 for piping materials other than non-corrugated stainless steel tubing. Section 1215.3 shall be used in conjunction with one of the methods described in Section 1215.1.1 through Section 1215.1.3 for non-corrugated stainless steel tubing.
CPC § 26-2019 Medium relevance — show source text
POLYETHYLENE (PE) PIPE FOR SEWER LATERALS

IAPMO IS 26-2019 [e4]

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

1 Scope

1.1 General

This standard shall govern the trenchless installation of polyethylene (PE) pipe for use in sanitary and storm sewers. The installed pipe shall comply with the requirements of the Uniform Plumbing Code (UPC [TM] ) published by the International Association of Plumbing and Mechanical Officials (IAPMO) as to grade and connections to existing pipe and shall also comply with this standard. This standard specifies requirements for the installation of the trenchless insertion of polyethylene (PE) pipe for use in sanitary and storm sewers. 1.2 Terminology

In this Standard,

(a) “shall” is used to express a requirement, i.e., a provision that the user is obliged to satisfy to comply with the Standard;

(b) “should” is used to express a recommendation, but not a requirement;

(c) “may” is used to express an option or something permissible within the scope of the Standard; and

(d) “can” is used to express a possibility or a capability.

Notes accompanying sections of the Standard do not specify requirements or alternative requirements; their purpose is to separate explanatory or informative material from the text. Notes to tables and figures are considered part of the table or figure and can be written as requirements.

2 Reference Publications

This Standard refers to the following publications, and where such reference is made, it shall be to the current edition of those publications, including all amendments published thereto.

ASTM International

ASTM D3261

Standard Specification for Butt Heat Fusion Polyethylene (PE) Plastic Fittings for Polyethylene (PE) Plastic Pipe and Tubing

ASTM F714

Standard Specification for Polyethylene (PE) Plastic Pipe (DR-PR) Based on Outside Diameter

ASTM F894

Standard Specification for Polyethylene (PE) Large Diameter Profile Wall Sewer and Drain Pipe

ASTM F1055

Standard Specification for Electrofusion Type Polyethylene Fittings for Outside Diameter Controlled Polyethylene and Crosslinked Polyethylene (PEX) Pipe and Tubing

ASTM F2620

Standard Practice for Heat Fusion Joining of Polyethylene Pipe and Fittings

3 Abbreviations

The following abbreviations apply in this Standard:

PE — Polyethylene

HDPE — High Density Polyethylene

4 General

4.1 Product Requirements

Polyethylene (PE) sewer pipe or tubing and fitting joining methods shall be installed in accordance

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IS 26

with the manufacturer’s installation instructions and comply with ASTM F714, ASTM F894 the applicable nationally recognized standard.

4.2 HDPE Materials

HDPE Extra High Molecular Weight 3408 SDR 17 Pipe Socket-Type PE Fittings for Outside Diameter Controlled.
CPC § 4.6 Medium relevance — show source text
Considerations are soil density; clearance from obstacles, utilities, and structures; location of bends, and water service locations. Excavations and shoring shall be in accordance with jurisdictional safety requirements. (c) Set Up Fuse the proper length of polyethylene pipe in accordance with ASTM F2620, or ASTM D3261 and fuse the end to a small length that is attached to the pulling head. A rod pusher cable is pushed through the damaged host pipe and attached to the pulling cable, which is then drawn through the pipe. The clevis end of the cable is attached to the pulling head. The pulling equipment is then set up according to the manufacturer’s instructions.

(d) Pulling Pull the pulling head through. Once the pull is done, complete the connection to the existing piping.

4.6 Cleanouts

4.6.1 Plug Each cleanout fitting for cast-iron pipe shall consist of a cast-iron or brass body and an approved plug. Each cleanout for galvanized wrought-iron, galvanized steel, copper, or brass pipe shall consist of a brass plug as specified in Table 1, or a standard weight brass cap, or an approved ABS or PVC plastic plug, or an approved stainless-steel cleanout or plug. Plugs shall have raised square heads or approved countersunk rectangular slots. 4.6.2 Approved Each cleanout fitting and each cleanout plug, or cap shall be of an approved type.

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4.6.3 Watertight and Gastight

Cleanouts shall be designed to be watertight and gastight.

5 Testing and Inspection Requirements

5.1 Media

The piping of the building sewer shall be tested with water. The Authority Having Jurisdiction shall be permitted to require the removal of cleanouts, etc., to ascertain whether the pressure has reached all parts of the system.

5.2 Water Test

The system shall be tested by plugging the end of the building sewer at its points of connection to the public sewer or private sewage disposal system and completely filling the building sewer with water from the lowest to the highest point thereof.

5.3 Inspections

The completed piping shall be internally inspected by camera unless waived by the Administrative Authority.

TABLE 1

CLEANOUTS (See Section 4.6.1)

NPS SIZE OF CLEANOUT
(inches) THREADS PER INCH

1.5 1.5 11.5

2 1.5 11.5

2.5 2.5 8

3 2.5 8

4 & larger 3.5 8

Note: For SI units: 1 inch = 25 mm

Uniform Plumbing Code References

The following sections of the 2024 Uniform Plumbing Code apply.

105.2 Required Inspections

105.2.2 Other Inspections

105.3 Testing of Systems

301.2 Minimum Standards

309.0 Workmanship

312.0 Protection of Piping, Materials, and Structures
CPC § 310.13 Medium relevance — show source text
ante rooms.

310.13 [SFM] For applications listed in Section 1.11.0 regu- lated by the Office of the State Fire Marshal, plastic piping shall not be exposed as a portion of the interior room finish in a build- ing or structure if the piping has a flame-spread rating exceed- ing 75 when tested in accordance with ASTM E84, “Test for Surface Burning Characteristics of Building Materials.” 310.14 Services/Systems and Utilities. [OSHPD 1, 2, 4 & 5] Refer to Sections 1224.4.1, 1225.2.1 and 1228.4.1.1, Cal- ifornia Building Code. 310.15 Telephone and Data Equipment Rooms.

[OSHPD 1, 4 & 5] Where telecommunications service entrance rooms, technology equipment centers, or technology distribution rooms are provided in accordance with Section 1224.5 of the California Building Code, plumbing equipment and fixtures that are not directly related to the support of the room shall not be installed in or pass through the room.

311.0 Independent Systems. 311.1 General. The drainage system of each new building and new work installed in an existing building shall be separate and independent from that of any other building, and, where available, every building shall have an independent connection with a public or private sewer.

Exception: Where one building stands in the rear of another building on an interior lot, and no public or private sewer is available or can be constructed to the rear building through an adjoining court, yard, or driveway, the building drain from the front building shall be permitted to be extended to the rear building.

Note: Accessory dwelling units are not required to have inde- pendent service utility (drainage) connections provided they meet the specific requirements in Government Code Section 65852.2.

312.0 Protection of Piping, Tubing, Materials, and Structures.

312.1 General. Piping passing under or through walls shall be protected from breakage. Piping passing through or under cinders or other corrosive materials shall be protected from external corrosion in an approved manner. Approved provisions shall be made for expansion of hot water piping. Voids around piping passing through concrete floors on the ground shall be sealed.

312.2 Installation. Piping in connection with a plumbing system shall be so installed that piping or connections will not be subject to undue strains or stresses, and provisions shall be made for expansion, contraction, and structural settlement. No plumbing piping shall be directly embedded in concrete or masonry. No structural member shall be seriously weakened or impaired by cutting, notching, or otherwise, as defined in the California Building Code or California Residential Code . 312.3 Building Sewer and Drainage Piping. No building sewer or other drainage piping or part thereof, constructed of materials other than those approved for use under or within a building, shall be installed under or within 2 feet (610 mm) of a building or structure, or less than 1 foot (305 mm) below the surface of the ground. 312.4 Corrosion, Erosion, and Mechanical Damage. Piping subject to corrosion, erosion, or mechanical damage shall be protected in an approved manner. **312.5 Protectively Coated Pipe.
CPC § 4.1 Medium relevance — show source text
- 100°F
  (16°C-38°C)|1 h|6 h|2 h|12 h|6 h|24 h| |40°F-60°F
  (4°C-16°C)|2 h|12 h|4 h|24 h|12 h|48 h| |10°F- 40°F
  (-12°C+4°C)|8 h|48 h|16 h|96 h|48 h|8 days| |*If gaps or loose fits are encountered in the system, double these cure times.|*If gaps or loose fits are encountered in the system, double these cure times.|*If gaps or loose fits are encountered in the system, double these cure times.|*If gaps or loose fits are encountered in the system, double these cure times.|*If gaps or loose fits are encountered in the system, double these cure times.|*If gaps or loose fits are encountered in the system, double these cure times.|*If gaps or loose fits are encountered in the system, double these cure times.|
2025 CALIFORNIA PLUMBING CODE 467

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FIGURE 1

LOCATION OF THRUST BLOCKS (STANDARD AND METRIC COMBINED) A COMPARISON OF THRUST-BLOCK AREAS (See Section 4.1)

468 2025 CALIFORNIA PLUMBING CODE

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FIGURE 2

THRUST BLOCK BEARING AREA (See Section 5.2.2)

2025 CALIFORNIA PLUMBING CODE 469

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Uniform Plumbing Code References for Ductile Iron and PVC Pressure Building Supply and Exterior Cold-Water Piping

The following sections of the 2024 Uniform Plumbing Code apply to ductile iron and PVC pressure building supply and exterior cold-water piping.

Chapter 3 General Regulations

309.0 Workmanship

312.0 Protection of Piping, Materials, and Struc tures

313.0 Hangers, Supports, and Anchors

314.0 Trenching, Excavation, and Backfill

Chapter 6 Water Supply and Distribution

604.0 Materials (water piping)

Table 604.1 Materials for Building Supply and Water Distribution Piping and Fittings

605.4 Ductile Iron Pipe and Joints

605.12 PVC Plastic Pipe and Joints

605.16.2 Plastic Pipe to Other Materials

609.0 Installation, Testing, Unions, and Location

Abbreviations

IAPMO International Association of Plumbing and Mechanical Officials

UPC Uniform Plumbing Code published by IAPMO

AWWA American Water Works Association

CSA Canadian Standards Association

Applicable Standards.

ASME B16.4 Gray Iron Threaded Fittings Classes 125 and 250

ASTM D1785 Poly (Vinyl Chloride) (PVC) Plastic Pipe, Schedules 40, 80, and 120

ASTM D2241 Poly (Vinyl Chloride) (PVC) Pressure-Rated Pipe (SDR Series)

NPS	SIZE OF CLEANOUT (inches)	THREADS PER INCH
1.5	1.5	11.5
2	1.5	11.5
2.5	2.5	8
3	2.5	8
4 & larger	3.5	8

CPC § 2.2 Medium relevance — show source text

2.2_
407.2.3
407.2.4
407.2.4.1
408.3
408.3.1
408.3.2
408.6
408.7 Exception 1
411.2
411.2.2
411.2.2.1
411.2.3
411.2.4
412.1
412.1.1
412.1.2
412.1.3
412.1.4.1
413.2
415.1
417.1.1
417.1.2
420.2.1
420.2.2
||||X|||||||||||||||||||||

2025 CALIFORNIA PLUMBING CODE 57

CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE

CHAPTER 4 - PLUMBING FIXTURES AND FIXTURE FITTINGS (continued) (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 Adopt Entire Chapter Adopt Entire Chapter as amended (amended sections listed below) Adopt only those sections that are listed below Chapter/Section 422.1 422.1 Exception Table 422.1 422.1.1 422.1.3 422.1.4 422.2 422.2 Exceptions 422.2 Exception (4) 422.3.1 & Exception 422.4 422.5 422.6 Exception (3) 422.7 Exception (2) 422.8 422.9 422.10 422.11 Table 4-1 Table 4-2 Table 4-3 Table 4-4	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 Adopt Entire Chapter Adopt Entire Chapter as amended (amended sections listed below) Adopt only those sections that are listed below Chapter/Section 422.1 422.1 Exception Table 422.1 422.1.1 422.1.3 422.1.4 422.2 422.2 Exceptions 422.2 Exception (4) 422.3.1 & Exception 422.4 422.5 422.6_Exception (3) 422.7_Exception (2) 422.8 422.9 422.10 _422.

CPC § 5.5 Medium relevance — show source text
5|5.5|5.5| |6|Dishwasher|1|0.5|1.3|1.3| |7|Kitchen Faucet|1|2.0|2.2|2.2| |8|Laundry Faucet|0|2.0|2.0|2.0| |9|Lavatory Faucet|1|2.0|1.5|1.5| |10|Shower, per head|0|4.5|2.0|2.0| |11|Water Closet, 1.28 GPF Gravity Tank|0|1.0|3.0|3.0| |12|Other Fixture 1|0|0.0|0.0|6.0| |13|Other Fixture 2|0|0.0|0.0|6.0| |14|Other Fixture 3|0|0.0|0.0|6.0| |Total Number of Fixtures|Total Number of Fixtures|5||RESET|RUN WATER DEMAND
CALCULATOR| |99th Percentile Demand Flow =|99th Percentile Demand Flow =|7.7 GPM||||

For SI units: 1 gallon per minute = 0.66 L/s, 1 gallon = 3.785 L

FIGURE 5 WATER DEMAND CALCULATOR FOR THE HOT WATER BRANCH (EXAMPLE 4)

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CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE

APPENDIX N - IMPACT OF WATER TEMPERATURE ON THE POTENTIAL FOR SCALDING AND LEGIONELLA GROWTH

(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.)
CPC § 101.5 Medium relevance — show source text
B 101.5 Trap Sizes. Trap sizes are required to be equivalent to the branches they serve (two pipe sizes larger than normal), and tailpieces between fixtures or floor drains and such traps shall be reduced to normal size.

B 101.6 Layout Drawings. Duplicate layout drawings of each such proposed piping system shall be presented to the Authority Having Jurisdiction and approval obtained before an installation is made. Complicated layouts shall be checked by qualified personnel. B 101.6.1 Example of Sizing. A floor drain normally requires a 2 inch (50 mm) trap and waste. On a combination waste and vent system, both trap and waste shall be increased two pipe sizes (through 2 [1] ⁄ 2 inches and 3 inches) (65 mm and 80 mm), which would make the trap 3 inches (80 mm). Pipe sizes recognized for this purpose are 2 inches, 2 [1] ⁄ 2 inches, 3 inches, 3 [1] ⁄ 2 inches, 4 inches, 4 [1] ⁄ 2 inches, 5 inches, 6 inches, etc. (50 mm, 65 mm, 80 mm, 90 mm, 100 mm, 115 mm, 125 mm, 150 mm, etc.). The tailpiece between the floor drain and its trap shall be 2 inches (50 mm) (or normal size) to ensure that the amount of wastewater entering the trap partially fills the waste branch. A 3 inch (80 mm) floor drain would thus require a 4 inch (100 mm) trap, and a 4 inch (100 mm) floor drain would require a 5 inch (125 mm) trap for the reasons previously stated.

WHERE IN DOUBT, CHECK WITH YOUR LOCAL Authority Having Jurisdiction.

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CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE

APPENDIX C - ALTERNATE PLUMBING SYSTEMS

(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.)

CPC § 5.2 Medium relevance — show source text

DIAMETER OF GUTTER (1⁄8 inch per foot slope)	MAXIMUM RAINFALL RATES BASED ON ROOF AREA (square feet)	Col3	Col4	Col5	Col6
inches	2 (in/h)	3 (in/h)	4 (in/h)	5 (in/h)	6 (in/h)
3	480	320	240	192	160
4	1020	681	510	408	340
5	1760	1172	880	704	587
6	2720	1815	1360	1085	905
7	3900	2600	1950	1560	1300
8	5600	3740	2800	2240	1870
10	10 200	6800	5100	4080	3400

DIAMETER OF GUTTER (1⁄4 inch per foot slope)	MAXIMUM RAINFALL RATES BASED ON ROOF AREA (square feet)	Col3	Col4	Col5	Col6
inches	2 (in/h)	3 (in/h)	4 (in/h)	5 (in/h)	6 (in/h)
3	680	454	340	272	226
4	1440	960	720	576	480
5	2500	1668	1250	1000	834
6	3840	2560	1920	1536	1280
7	5520	3680	2760	2205	1840
8	7960	5310	3980	3180	2655
10	14 400	9600	7200	5750	4800

DIAMETER OF GUTTER (1⁄2 inch per foot slope)	MAXIMUM RAINFALL RATES BASED ON ROOF AREA (square feet)	Col3	Col4	Col5	Col6
inches	2 (in/h)	3 (in/h)	4 (in/h)	5 (in/h)	6 (in/h)
3	960	640	480	384	320
4	2040	1360	1020	816	680
5	3540	2360	1770	1415	1180
6	5540	3695	2770	2220	1850
7	7800	5200	3900	3120	2600
8	11 200	7460	5600	4480	3730
10	20 000	13 330	10 000	8000	6660

For SI units: 1 inch = 25 mm, [1] ⁄ 16 inch per foot = 5.2 mm/m, 1 inch per hour = 25.4 mm/h, 1 square foot = 0.0929 m [2]

2025 CALIFORNIA PLUMBING CODE 211

212 2025 CALIFORNIA PLUMBING CODE

CPC § 25.4 Medium relevance — show source text

provide mid-story guides| |PE-RT|Insert and Compression|1 inch and smaller, 32 inches;
11⁄4 inches and larger, 4 feet
|Base and each floor;
provide mid-story guides| |Polypropylene (PP)|Fusion weld (socket, butt, sad-
dle, electrofusion), threaded
(metal threads only), or
mechanical|1 inch and smaller, 32 inches;
11⁄4 inches and larger, 4 feet|Base and each floor;
provide mid-story guides|

For SI units: 1 inch = 25.4 mm, 1 foot = 304.8 mm

Notes: 1 Support adjacent to joint, not to exceed 18 inches (457 mm). 2 Brace not to exceed 40 foot (12 192 mm) intervals to prevent horizontal movement. 3 Support at each horizontal branch connection. 4 Hangers shall not be placed on the coupling. 5 Vertical water lines shall be permitted to be supported in accordance with recognized engineering principles with regard to expansion and contraction, where first approved by the Authority Having Jurisdiction.

2025 CALIFORNIA PLUMBING CODE 55

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

56 2025 CALIFORNIA PLUMBING CODE

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

CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE

CHAPTER 4 - PLUMBING FIXTURES AND FIXTURE FITTINGS

(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
Adopt Entire Chapter
Adopt Entire Chapter as
amended (amended
sections listed below)
Adopt only those sections
that are listed below
Chapter/Section
Note Under Chapter Title
401.3
403.1
403.2
403.3
407.2
407.2.1
407.2.2
407.2.3
407.2.4
407.2.4.1
408.3
408.3.1
408.3.2
408.6
408.7 Exception 1
411.2
411.2.2
411.2.2.1
411.2.3
411.2.4
412.1
412.1.1
412.1.2
412.1.3
412.1.4.1
413.2
415.1
417.1.1
417.1.2
420.2.1
420.2.

CPC § 1.4 Medium relevance — show source text

340 2025 CALIFORNIA PLUMBING CODE

REFERENCED STANDARDS

TABLE 1701.1 (continued) REFERENCED STANDARDS

STANDARD NUMBER	STANDARD TITLE	APPLICATION	REFERENCED SECTION
ASTM C1540-2020	Standard Specification for Heavy-Duty Shielded Couplings Joining Hubless Cast Iron Soil Pipe and Fittings	Joints	705.2.2
ASTM C1563-2008 (R2021)	Standard Test Method for Gaskets for Use in Connection with Hub and Spigot Cast Iron Soil Pipe and Fittings for Sanitary Drain, Waste, Vent, and Storm Piping Applications	Joints	705.2.2
ASTM C1822-2021	Standard Specification for Insulating Covers on Accessible Lavatory Piping	Miscellaneous	403.3
ASTM D1253-2014	Standard Test Method for Residual Chlorine in Water	Miscellaneous	1506.10.6, 1603.4.1
ASTM D1785-2021a	Standard Specification for Poly (Vinyl Chloride) (PVC) Plastic Pipe, Schedules 40, 80, and 120	Piping	Table 604.1, Table 701.

CPC § 312.0 Medium relevance — show source text
312.0 Protection of Piping, Materials, and Structures

314.0 Trenching, Excavation, and Backfill

701.3 Drainage Fittings

705.5.1.1 Butt Fusion Joints

705.5.1.2 Electro-Fusion Joints

705.5.1.3 Socket-Fusion Joints

723.0 Building Sewer Test

TABLE 1

CLEANOUTS (See Section 4.6.1)

The following standards from Tables 1701.1 and 1701.2 of the 2024 Uniform Plumbing Code apply.

Table 1701.1 Standards

ASTM D2239 Polyethylene (PE) Plastic Pipe (SIDRPR) Based on Controlled Inside Diameter

ASTM D2683 Socket-Type Polyethylene Fittings for Outside Diameter-Controlled Polyethylene Pipe and Tubing

ASTM D3261 Butt Heat Fusion Polyethylene (PE) Plastic Fittings for Polyethylene (PE) Plastic Pipe and Tubing

ASTM F714 Polyethylene (PE) Plastic Pipe (DRPR) Based on Outside Diameter

ASTM F894 Polyethylene (PE) Large Diameter Profile Wall Sewer and Drain Pipe

ASTM F1055 Electrofusion Type Polyethylene Fittings for Outside Diameter Controlled Polyethylene and Crosslinked Polyethylene (PEX) Pipe and Tubing

ASTM F2620 Heat Fusion Joining of Polyethylene Pipe and Fittings

Table 1701.2 Standards

ASTM D2657 Heat Fusion Joining of Polyolefin Pipe and Fittings

IAPMO PS 25 Metallic Fittings for Joining Polyethylene Pipe for Water Service and Yard Piping

Note: For SI units: 1 inch = 25 mm

2025 CALIFORNIA PLUMBING CODE 453

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

454 2025 CALIFORNIA PLUMBING CODE

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

"The information contained in this appendix is not part of this American National Standard (ANS) and has not been processed in accordance with ANSI's requirements for an ANS. As such, this appendix may contain material that has not been subjected to public review or a consensus process. In addition, it does not contain requirements necessary for conformance to the standard."

The following IAPMO Installation Standard is included here for the convenience of the users of the Uniform Plumbing Code. It is not considered as a part of the Uniform Plumbing Code unless formally adopted as such. This Installation Standard is an independent, stand-alone document published by the International Association of Plumbing and Mechanical Officials and is printed herein by the expressed written permission of IAPMO.

INSTALLATION STANDARD FOR PEX TUBING SYSTEMS

FOR HOT- AND COLD-WATER DISTRIBUTION

IAPMO IS 31-2022

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

1 Scope

1.1 General

1.1.1 This Standard specifies requirements for the installation of SDR 9 CTS crosslinked polyethylene (PEX) tubing and fittings, including cold-expansion, crimp, press, and mechanical compression fittings, intended for hot- and cold-water distribution systems within buildings.

1.1.2 This Standards applies to

Frequently asked questions

Can I use the CPC tables for both natural gas and propane?

Yes — the CPC provides separate table sets for natural gas and propane in § 1215.2; be sure you read the correct table for the fuel type and inlet pressure indicated.

When should I use the equations in § 1215.3 instead of the tables?

Use § 1215.3 (equations and Table 1215.3) for smooth‑walled tubing (non‑corrugated stainless steel tubing) or when you prefer/need an engineered calculation; the code explicitly allows equations as the sizing method.

What if my run is longer or demand higher than the tables cover?

If conditions fall outside the tables’ ranges (long runs, very large demand, variable pressures), the code requires you to size the system by standard engineering methods acceptable to the Authority Having Jurisdiction.

Do I have to include fittings when I measure length?

Yes — you must use the equivalent length (straight pipe length plus fittings converted to equivalent feet) when looking up lengths in the tables or using the equations, per the methods in § 1215.1.

I can’t find § 1215.4 or § 1215.5 in my copy — is that normal?

In the uploaded files I was able to retrieve § 1215.1–1215.3, but I could not find the text of § 1215.4 or § 1215.5 in the provided excerpts. If your printed code contains those sections, follow them; otherwise check the full CPC/approved edition or contact your Authority Having Jurisdiction.

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19.17 [(]

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