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Chapter 8 — COMPLIANCE FORMS, WORKSHEETS AND REFERENCE MATERIAL

Section A5.303 — INDOOR WATER USE

2025 California Green Building Standards Code (Title 24, Part 11) · 2025 edition · updated 2026-07-25 · California

TABLE A5.303.2.2—WATER USE BASELINE (PERFORMANCE METHOD)3

FIXTURE TYPE BASELINE FLOW RATE DURATION DAILY USES OCCUPANTS2
Showerheads 1.8 gpm @ 80 psi 5 min. 1 X2a
Lavatory faucets nonresidential 0.5 gpm @ 60 psi .25 min. 3 X
Kitchen faucets 1.8 gpm @ 60 psi 4 min. 1 X2b
Replacement aerators 2 gpm @ 60 psi X
Wash fountains 1.8 gpm/20 [rim space (in.) @ 60 psi] X
Metering faucets 0.20 gallons/cycle .25 min. 3 X
Metering faucets for wash fountains 0.20 gallons/cycle/20 [rim space (in.) @ 60 psi] .25 min. 1 male1
3 female		 X
Gravity tank type water closets 1.28 gallons/flush 1 flush 1 male1
3 female		 X
Flushometer tank water closets 1.28 gallons/flush 1 flush 1 male1
3 female		 X
Flushometer valve water closets 1.28 gallons/flush 1 flush 1 male1
3 female		 X
Electromechanical hydraulic water
closets		 1.28 gallons/flush 1 flush 1 male1
3 female		 X
Urinals 0.5 or 0.1254 gallons/flush 1 flush 2 male X
1. The daily use number shall be increased to three if urinals are not installed in the room.
2. Refer to Table 4-1, Chapter 4, 2025_California Plumbing Code_, for occupant load factors.
a. Shower use by occupants depends on the type of use of a building or portion of a building, e.g., total occupant load for a health club, but only a fraction of the occupants
in an office building as determined by the anticipated number of users.
b. Kitchen faucet use is determined by the occupant load of the area served by the fixture.
3. Use worksheet WS-1 to calculate baseline water use.
4. Floor-mounted urinals @ 0.5 GPF or wall-mounted urinals @ 0.125 GPF.

A5.303.2.3.1 Tier 1 – 12-percent savings. A schedule of plumbing fixtures and fixture fittings that will reduce the overall use of potable water within the building by 12 percent shall be provided. The reduction shall be based on the maximum allowable water use per plumbing fixture and fitting as required by the California Building Standards Code. The 12-percent reduction in potable water use shall be demonstrated by one of the following methods:

  1. Prescriptive method. Each plumbing fixture and fitting shall not exceed the maximum flow rate at greater than or equal to 12-percent reduction as specified in Table A5.303.2.3.1; or
  2. Performance method. A calculation demonstrating a 12-percent reduction in the building “water use baseline” as established in Table A5.303.2.2 shall be provided.

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

APPENDIX A5 — NONRESIDENTIAL VOLUNTARY MEASURES

TABLE A5.303.2.3.1—FIXTURE FLOW RATES (PRESCRIPTIVE METHOD)

FIXTURE TYPE BASELINE FLOW RATE2 MAXIMUM FLOW RATE AT≥** 12 PERCENT**
REDUCTION
Showerheads 1.8 gpm @ 80 psi 1.6 gpm @ 80 psi
Lavatory faucets nonresidential3 0.5 gpm @ 60 psi 0.35 gpm @ 60 psi
Kitchen faucets3 1.8 gpm @ 60 psi 1.6 gpm @ 60 psi
Wash fountains 1.8 gallons/cycle/20 [rim space (in.) @ 60 psi] 1.6 gpm/20 [rim space (in.) @ 60 psi]
Metering faucets 0.20 gallons/cycle 0.18 gallons/cycle
Metering faucets for wash fountains 0.20 gallons/cycle/20 [rim space (in.) @ 60 psi] 0.18 gallons/cycle 20 [rim space (in.) @ 60 psi]
Gravity tank type water closets 1.28 gallons/flush 1.12 gallons/flush1
Flushometer tank water closets 1.28 gallons/flush 1.12 gallons/flush1
Flushometer valve water closets 1.28 gallons/flush 1.12 gallons/flush1
Electromechanical hydraulic water closets 1.28 gallons/flush 1.12 gallons/flush1
Urinals 0.5 or 0.1254 gallons/flush 0.44 or 0.11 gallons/flush
1. Includes water closets with an effective flush rate of 1.12 gallons or less when tested per ASME A 112.19.2 and ASME A 112.19.14.
2. See Table A5.503.2.2 for additional notes and references.
3. Where complying faucets are unavailable, aerators rated at 0.35 gpm or other means may be used to achieve reduction.
4. Floor-mounted urinals @ 0.5 GPF or wall-mounted urinals @ 0.125 GPF.

A5.303.2.3.2 Tier 2 – 20-percent savings. A schedule of plumbing fixtures and fixture fittings that will reduce the overall use of potable water within the building by 20 percent shall be provided. A calculation demonstrating a 20-percent reduction in the building “water use baseline” as established in Table A5.303.2.2 shall be provided. A5.303.2.3.3 25-percent savings. A schedule of plumbing fixtures and fixture fittings that will reduce the overall use of potable water within the building by 25 percent shall be provided. A calculation demonstrating a 25-percent reduction in the building “water use baseline” as established in Table A5.303.2.2 shall be provided. A5.303.2.3.4 Nonpotable water systems for indoor use. Utilizing nonpotable water systems (such as captured rainwater, treated graywater and recycled water) intended to supply water closets, urinals and other allowed uses, may be used in the calculations demonstrating the 12-, 20- or 25-percent reduction. The nonpotable water systems shall comply with the current edition of the California Plumbing Code.

A5.303.3 Appliances and fixtures for commercial application. Appliances and fixtures shall meet the following:

  1. Clothes washers shall have a maximum Water Factor (WF) that will reduce the use of water by 10 percent below the California Energy Commissions’ WF standards for commercial clothes washers located in Title 20 of the California Code of Regulations.
  2. Dishwashers shall meet the following water use standards: a. Residential—ENERGY STAR.

i. Standard Dishwashers – 4.25 gallons per cycle. ii. Compact Dishwashers – 3.5 gallons per cycle. b. Commercial—Shall be in accordance with ENERGY STAR requirements. Refer to Table A5.303.3. 3. Ice makers shall be air cooled.

  1. Food steamers shall be connectionless or boilerless – and shall consume no more than 2 gallons of water per pan per hour, including condensate water, for batch type steamers, and no more than 5 gallons of water per pan per hour, including condensate water, for cook to order steamers.
  2. The use and installation of water softeners that discharge to the community sewer system may be limited or prohibited by local agencies if certain conditions are met.
  3. Combination ovens shall use a maximum of 1.5 gallons of water per hour per pan, including condensate water.
  4. Food waste pulping systems shall use no more than 2 gpm of potable water. 7.1. Note: potable water excludes on-site graywater use, such as dishwasher discharge water.

t discharge to the community sewer system may be limited or prohibited by local agencies if certain conditions are met. 6. Combination ovens shall use a maximum of 1.5 gallons of water per hour per pan, including condensate water. 7. Food waste pulping systems shall use no more than 2 gpm of potable water. 7.1. Note: potable water excludes on-site graywater use, such as dishwasher discharge water.

TABLE A5.303.3—COMMERCIAL DISHWASHER WATER USE

TYPE HIGH-TEMPERATURE—MAXIMUM GALLONS PER
RACK		 LOW-TEMPERATURE—MAXIMUM GALLONS PER
RACK
Single Tank Conveyor 0.70 (2.6 L) ≤ 0.79 (3 L)
Multiple Tank Conveyor ≤ 0.54 (2 L) ≤ 0.54 (2 L)
Stationary Single Tank Door ≤ 0.89 (3.4 L) ≤ 1.18 (4.5 L)
Under Counter ≤ 0.86 (3.3 L) ≤ 1.19 (4.5 L)
Pot, Pan and Utensil ≤ 0.58 GPSF ≤ 0.58 GPSF
Single Tank Flight Type GPH ≤ 2.975x + 55.00 GPH ≤ 2.975x + 55.00
Multiple Tank Flight Type GPH ≤ 4.96x + 17.00 GPH ≤ 4.96x + 17.00
Note: GPSF = gallons per square foot of rack; GPH = gallons per hour;
X = square feet of conveyor belt/minute (max conveyor speed sf/min as tested and certified to NSF/ANSI Standard 3)

APPENDIX A5-20 2025 CALIFORNIA GREEN BUILDING STANDARDS CODE

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

APPENDIX A5 — NONRESIDENTIAL VOLUNTARY MEASURES

A5.303.4 Water conserving plumbing fixtures and fittings.

A5.303.4.1 Nonwater urinals. Nonwater urinals with drain cleansing action are installed in accordance with the California Plumbing Code .

Where approved, nonwater urinals with drain cleansing action (formerly urinal, hybrids) as defined in Chapter 2, shall be considered waterless urinals.

A5.303.5 Dual plumbing. New buildings and facilities shall be dual plumbed for potable and recycled water systems for toilet flushing when recycled water is available as determined by the enforcement authority.

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▸ Contents — 2025 California Green Building Standards Code (Title 24, Part 11)
2025 California Green Building Standards Code (Title 24, Part 11)
  1. Chapter 1 — ADMINISTRATION
  2. Chapter 2 — DEFINITIONS
  3. Chapter 3 — GREEN BUILDING
  4. Chapter 4 — RESIDENTIAL MANDATORY MEASURES
  5. Chapter 4 — RESIDENTIAL MANDATORY MEASURES
  6. Chapter 4 — RESIDENTIAL MANDATORY MEASURES
  7. Chapter 4 — RESIDENTIAL MANDATORY MEASURES
  8. Chapter 4 — RESIDENTIAL MANDATORY MEASURES
  9. Chapter 5 — NONRESIDENTIAL MANDATORY MEASURES
  10. Chapter 5 — NONRESIDENTIAL MANDATORY MEASURES
  11. Chapter 5 — NONRESIDENTIAL MANDATORY MEASURES
  12. Chapter 5 — NONRESIDENTIAL MANDATORY MEASURES
  13. Chapter 5 — NONRESIDENTIAL MANDATORY MEASURES
  14. Chapter 6 — REFERENCED ORGANIZATIONS AND STANDARDS
  15. Chapter 7 — INSTALLER AND SPECIAL INSPECTOR QUALIFICATIONS
  16. ▸ Chapter 8 — COMPLIANCE FORMS, WORKSHEETS AND REFERENCE MATERIAL
    Overview
    1. Section A4.101 — GENERAL
    2. Section A4.102 — DEFINITIONS
    3. Section A4.103 — SITE SELECTION
    4. Section A4.104 — SITE PRESERVATION
    5. Section A4.105 — DECONSTRUCTION AND REUSE OF EXISTING MATERIALS
    6. Section A4.106 — SITE DEVELOPMENT
    7. Section A4.107
    8. Section A4.108 — INNOVATIVE CONCEPTS AND LOCAL ENVIRONMENTAL C…
    9. Section A4.201 — GENERAL
    10. Section A4.202 — DEFINITIONS
    11. Section A4.203 — PERFORMANCE APPROACH FOR NEWLY CONSTRUCTED BU…
    12. Section A4.204 — REQUIREMENTS FOR ALTERATIONS TO EXISTING BUIL…
    13. Section A4.301 — GENERAL
    14. Section A4.302 — DEFINITIONS
    15. Section A4.303 — INDOOR WATER USE
    16. Section A4.304 — OUTDOOR WATER USE
    17. Section A4.305 — WATER REUSE SYSTEMS
    18. Section A4.306 — INNOVATIVE CONCEPTS AND LOCAL ENVIRONMENTAL C…
    19. Section A4.401 — GENERAL
    20. Section A4.402 — DEFINITIONS
    21. Section A4.403 — FOUNDATION SYSTEMS
    22. Section A4.404 — EFFICIENT FRAMING TECHNIQUES
    23. Section A4.405 — MATERIAL SOURCES
    24. Section A4.406 — ENHANCED DURABILITY AND REDUCED MAINTENANCE
    25. Section A4.407 — WATER RESISTANCE AND MOISTURE MANAGEMENT
    26. Section A4.408 — CONSTRUCTION WASTE REDUCTION, DISPOSAL AND RE…
    27. Section A4.409 — LIFE CYCLE ASSESSMENT
    28. Section A4.410 — BUILDING MAINTENANCE AND OPERATION
    29. Section A4.411 — INNOVATIVE CONCEPTS AND LOCAL ENVIRONMENTAL C…
    30. Section A4.501 — GENERAL
    31. Section A4.502 — DEFINITIONS
    32. Section A4.503 — FIREPLACES
    33. Section A4.504 — POLLUTANT CONTROL
    34. Section A4.505 — INTERIOR MOISTURE CONTROL
    35. Section A4.506 — INDOOR AIR QUALITY AND EXHAUST
    36. Section A4.507 — ENVIRONMENTAL COMFORT
    37. Section A4.508 — OUTDOOR AIR QUALITY
    38. Section A4.509 — INNOVATIVE CONCEPTS AND LOCAL ENVIRONMENTAL C…
    39. Section A4.601 — GENERAL
    40. Section A4.602 — RESIDENTIAL OCCUPANCIES APPLICATION CHECKLIST
    41. Section A4.602 — RESIDENTIAL OCCUPANCIES APPLICATION CHECKLIST…
    42. Section A4.602 — RESIDENTIAL OCCUPANCIES APPLICATION CHECKLIST…
    43. Section A4.602 — RESIDENTIAL OCCUPANCIES APPLICATION CHECKLIST…
    44. Section A4.602 — RESIDENTIAL OCCUPANCIES APPLICATION CHECKLIST…
    45. Section A4.602 — RESIDENTIAL OCCUPANCIES APPLICATION CHECKLIST…
    46. Section A4.602 — RESIDENTIAL OCCUPANCIES APPLICATION CHECKLIST…
    47. Section A5.101 — GENERAL
    48. Section A5.102 — DEFINITIONS
    49. Section A5.103 — SITE SELECTION
    50. Section A5.104 — SITE PRESERVATION
    51. Section A5.105 — DECONSTRUCTION AND REUSE OF EXISTING STRUCTURES
    52. Section A5.106 — SITE DEVELOPMENT
    53. Section A5.107 — BIRD-FRIENDLY BUILDING DESIGN
    54. Section A5.201 — GENERAL
    55. Section A5.202 — DEFINITIONS
    56. Section A5.203 — PERFORMANCE APPROACH
    57. Section A5.204 — MANDATORY REQUIREMENTS FOR ALTERATIONS TO EXI…
    58. Section A5.211 — RESERVED
    59. Section A5.212 — ELEVATORS, ESCALATORS AND OTHER EQUIPMENT
    60. Section A5.213 — ENERGY EFFICIENT FRAMING
    61. Section A5.301 — GENERAL
    62. Section A5.302 — DEFINITIONS
    63. Section A5.303 — INDOOR WATER USE
    64. Section A5.304 — OUTDOOR WATER USE
    65. Section A5.305 — WATER REUSE
    66. Section A5.401 — GENERAL
    67. Section A5.402 — DEFINITIONS
    68. Section A5.403 — FOUNDATION SYSTEMS
    69. Section A5.404 — EFFICIENT FRAMING TECHNIQUES
    70. Section A5.405 — MATERIAL SOURCES
    71. Section A5.406 — ENHANCED DURABILITY AND REDUCED MAINTENANCE
    72. Section A5.408 — CONSTRUCTION WASTE REDUCTION, DISPOSAL AND RE…
    73. Section A5.409 — LIFE CYCLE ASSESSMENT
    74. Section A5.501 — GENERAL
    75. Section A5.502 — DEFINITIONS
    76. Section A5.504 — POLLUTANT CONTROL
    77. Section A5.507 — ENVIRONMENTAL COMFORT
    78. Section A5.508 — OUTDOOR AIR QUALITY
    79. Section A6.106 — SITE DEVELOPMENT
    80. Section A6.202 — DEFINITIONS
    81. Section A6.203 — PERFORMANCE APPROACH
    82. Section A6.204 — PRESCRIPTIVE APPROACH
    83. Section A6.205 — [OSHPD 1 & 4]—BUILDING ENVELOPE
    84. Section A6.207 — [OSHPD 1, 2 & 4]—HVAC DESIGN, EQUIPMENT AND I…
    85. Section A6.210 — [OSHPD 1, 2 & 4]—APPLIANCES
    86. Section A6.401 — GENERAL
    87. Section A6.407 — [OSHPD 1, 2 & 4]—WATER RESISTANCE AND MOISTUR…
    88. Section A6.408 — CONSTRUCTION WASTE REDUCTION, DISPOSAL AND RE…
    89. Section A6.410 — BUILDING MAINTENANCE AND OPERATION
    90. Section A6.504 — POLLUTANT CONTROL
    91. Section A6.505 — [OSHPD 1, 2 & 4]—INDOOR MOISTURE CONTROL

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