Fixture Water Demand Chart — Maximum GPM & GPF

Every fixture's water numbers in one place: the federal EPAct maximums that anchor both model codes, IPC Table 604.4 (2021 edition; unchanged 2015–2024) and the UPC's per-section limits (2021 edition), the EPA WaterSense levels a spec can call for, and the design flows a supply system must actually deliver at the fixture — including the 25 GPM a flushometer valve draws.

Federal baseline — EPAct 1992 as enforced today

42 USC 6295

The national maximums for fixtures manufactured since 1994, as currently enforced under the federal energy act and its referenced ASME standards. Both model codes carry these same values.
Product	Max	Basis
Shower head	2.5 gpm	at 80 psi
Lavatory & kitchen faucet *	2.2 gpm	at 60 psi
Metering faucet	0.25 gal	per cycle
Water closet	1.6 gal	per flush
Urinal	1.0 gal	per flush

* The 1992 statute wrote faucets at 2.5 gpm @ 80 psi; its ASME A112.18.1 update mechanism moved the enforceable federal maximum to 2.2 gpm @ 60 psi, where it stands today (10 CFR 430.32).

IPC — maximum flow rates and consumption

IPC Table 604.4

Maximum flow rate or consumption per fixture fitting, values per IPC Table 604.4 (2021 edition).
Fixture fitting	Max	Basis
Lavatory faucet, private	2.2 gpm	at 60 psi
Lavatory faucet, public (metering)	0.25 gal	per metering cycle
Lavatory faucet, public (other than metering)	0.5 gpm	at 60 psi
Shower head	2.5 gpm	at 80 psi
Sink faucet	2.2 gpm	at 60 psi
Urinal	1.0 gal	per flushing cycle
Water closet	1.6 gal	per flushing cycle

A handheld shower spray counts as a shower head. IPC 604.4 permits higher consumption for: blowout-design water closets (3.5 gal per flush), vegetable sprays, clinical sinks (4.5 gal per flush), service sinks, and emergency showers.

UPC — maximum consumption, per section

UPC Chapter 4

The UPC prints no single consumption table — each fixture's limit lives in its own Chapter 4 section (2021 edition). The base-code values match the federal baseline.
Fixture	Max	Basis	Cite
Water closet	1.6 gal	per flush	UPC 411.2
Urinal	1.0 gal	per flush (average)	UPC 412.1
Shower head	2.5 gpm	at 80 psi	UPC 408.2
Lavatory faucet, public	0.5 gpm	at 60 psi	UPC 407.2.1
Lavatory faucet, metering	0.25 gal	per cycle	UPC 407.2.2
Sink faucet	2.2 gpm	at 60 psi	UPC 420.2
Lavatory faucet, private *	2.2 gpm	at 60 psi	ASME A112.18.1 / EPAct

* The base-2021-UPC sentence for private lavatories could not be independently double-confirmed (every accessible print was state-amended), so this row cites the referenced standard and federal law that govern the fixture — the value is the same 2.2 gpm @ 60 psi. Dual-flush water closets comply by effective flush volume — the average of two reduced flushes and one full flush (UPC 411.2.1, per ASME A112.19.14).

EPA WaterSense levels vs. the federal baseline

EPA WaterSense

What a WaterSense label certifies, next to the federal maximum it undercuts — the levels specs mean when they call for high-efficiency fixtures. Read directly from EPA's product specifications.
Product	WaterSense max	Federal max
Tank-type water closet	1.28 gpf	1.6 gpf
Lavatory faucet	1.5 gpm	2.2 gpm
Shower head	2.0 gpm	2.5 gpm
Flushing urinal	0.5 gpf	1.0 gpf

EPA has a paused draft faucet specification proposing 1.2 gpm — check the current spec before writing it into a spec book.

Design flow at the fixture — what the pipe must deliver

IPC Table 604.3 (selected)

Minimum flow and residual pressure the supply system must provide at the fixture under peak demand — the other side of the consumption limits. Selected, independently verified rows of IPC Table 604.3 (2021 edition); this is not the full table.
Fixture	Flow (GPM)	At pressure
Water closet, flushometer valve (siphonic)	25	35 psi
Water closet, flushometer valve (blowout)	25	45 psi
Water closet, flushometer tank	1.6	20 psi
Water closet, gravity tank (close-coupled)	3	20 psi
Urinal, flushometer valve	12	25 psi
Shower	2.5	8 psi
Lavatory, private	0.8	8 psi
Sink, residential	1.75	8 psi
Sink, service	3	8 psi

A flushometer valve consumes the same 1.6 gallons as a tank — but in about four seconds, which is the 25 GPM the piping must carry. That instantaneous draw is why flushometer-heavy systems size from their own demand curve on the WSFU-to-GPM chart.

Consumption is not demand — use each number for its job

The consumption tables (how much water a fixture may use) set what you can specify and purchase; the design-flow table (how fast the fixture draws it) is what sizes the piping. Estimating totals start from fixture units — the WSFU chart — while purchase specs check against WaterSense levels and any state cap. The flow rate calculator converts between GPM, GPH, and LPM where a spec mixes units.

State caps override the base codes — the biggest trap on this page

Many states cap fixtures well below the base codes — California (CALGreen/Title 20) enforces 1.28 gpf water closets, 1.8 gpm showerheads, and 1.2 gpm residential lavatory faucets; Washington, Colorado, Hawaii, New York, Maine, and Massachusetts enforce similar 1.28/0.5 levels. Sources quoting those numbers as "UPC" values are quoting amendments. Confirm the enforced code, its edition, and the state efficiency standards before ordering fixtures.

Common questions

How many GPM does a shower head use?

The federal maximum — carried identically into IPC Table 604.4 and UPC 408.2 — is 2.5 GPM measured at 80 psi. A WaterSense-labeled shower head is 2.0 GPM or less, and several states cap lower still: California enforces 1.8 GPM.

What is the maximum GPF for a toilet?

1.6 gallons per flush federally (EPAct 1992), and both model codes print the same number. WaterSense high-efficiency toilets flush at 1.28 gallons or less, which is the mandatory ceiling in California, Washington, Colorado, New York, and several other states. Blowout-design bowls, bedpan washers, and similar duty fixtures are excepted at 3.5 gallons.

How many GPM does a flushometer toilet demand?

While it consumes only 1.6 gallons per flush, a flushometer-valve water closet draws that water in roughly four seconds — the supply system must be designed to deliver 25 GPM at 35 psi (siphonic) or 45 psi (blowout) per IPC Table 604.3. A gravity-tank toilet needs just 3 GPM at 20 psi, which is why flushometer buildings size their piping from a different demand curve.

Are consumption limits the same under IPC and UPC?

On the federally anchored fixtures, yes: 1.6 gpf water closets, 1.0 gpf urinals, 2.5 gpm showers, 2.2 gpm sink faucets, 0.5 gpm public lavatories. The difference is where they live — one table (IPC 604.4) versus per-fixture sections (UPC Chapter 4) — and, far more importantly, what your state amends them to. Always check local amendments.

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