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:
- 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
- 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.
FIXTURE FLOW RATES
|FIXTURE TYPE||BASELINE FLOW RATE2||MAXIMUM FLOW RATE AT ≥ 12 PERCENT REDUCTION|
|Showerheads||2.0 gpm @ 80 psi||1.8 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|
- 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.
- See Table A5.503.2.2 for additional notes and references.
- Where complying faucets are unavailable, aerators rated at 0.35 gpm or other means may be used to achieve reduction.
- Floor-mounted urinals @ 0.5 GPF or wall-mounted urinals @ 0.125 GPF.