Why Your Out-of-State Showerhead Is Not Legal in California

Someone orders a showerhead they love from a national retailer, it arrives, and the inspector will not sign off on it. It happens often enough to be worth a short note, because the reason is not the fixture being poor quality. It is that California sets its own limits and they are tighter than the federal ones.

The three numbers

Under California’s appliance efficiency regulations, fixtures sold and installed here are limited to:

• Showerheads: 1.8 gallons per minute at 80 psi
• Bathroom basin taps: 1.2 gallons per minute at 60 psi
• Toilets: 1.28 gallons per flush

The federal standards are 2.5, 2.2 and 1.6 respectively. So a showerhead that is perfectly legal in most of the country delivers nearly forty percent more water than California permits, and a compliant-elsewhere toilet uses a quarter more per flush.

This is why a fixture ordered from a national site can fail. Larger retailers usually filter their California listings correctly, but the filtering is not universal, and it is least reliable on smaller specialist sites and on anything bought secondhand or brought from a previous house in another state.

The practical check

Before ordering, look for the flow rate printed on the specification sheet rather than the marketing copy. Showerheads have the gpm figure stamped on the fixture or the spray face itself in most cases. Toilets carry the gpf figure near the seat hinge or inside the tank. If a product page does not state the number at all, that is a reason to keep looking.

Multi-outlet showers are where this gets interesting. The limit applies per showerhead, but there are separate rules about how many outlets may run at once, which is why most systems with a rain head and a handset are designed with a diverter rather than simultaneous flow. It is a design question worth settling early, because it affects the valve specified at rough-in, which is months before anyone thinks about the showerhead.

Does a 1.8 gpm shower feel worse

Twenty years ago, sometimes. Now, mostly not. The engineering that went into hitting these limits produced heads that shape and pressurise the spray rather than simply restricting it, and a good 1.8 gpm head from a serious manufacturer generally outperforms a cheap unrestricted one. Where people do notice the difference is in very large rain heads, where the whole appeal is a wide low-pressure sheet of water and there is less to work with.

If shower feel matters to you, this is worth spending money on rather than treating as a commodity, and worth trying in a showroom rather than choosing from a photograph.

Where these rules sit

The flow limits come from the appliance efficiency regulations, and they are cross-referenced by CalGreen, which is Part 11 of Title 24, the California Building Standards Code. The current edition is the 2025 code cycle, which took effect on 1 January 2026 and applies to permit applications submitted on or after that date. Projects with complete applications in before then remain on the 2022 cycle. The California Energy Commission publishes the standards and the effective dates.

The City of Mountain View lists the same three figures on its own bathroom remodel permit requirements, alongside the electrical and glazing requirements for the room. It also notes the one bathroom job that does not need a permit at all: swapping a toilet for a 1.28 gallon per flush model in the same position.

The others in the same family

While you are checking fixtures, the same permit page covers a few requirements that come up at inspection and are easier to design for than to retrofit:

• Ground fault protected receptacles within three feet of each basin, on a dedicated 20 amp circuit
• No electrical panel inside a bathroom
• Mechanical exhaust ducted to outside air for any bathroom with a tub or shower, with an operable window not accepted as a substitute
• Safety glazing, meaning tempered glass, in and around the tub or shower enclosure

None of these are onerous. All of them are cheaper to plan for at rough-in than to correct after tile.

For the full permit sequence, see the Mountain View bathroom permit guide. For how ventilation gets solved in houses with no attic, which is a genuine problem in this city, see venting a bathroom with no attic.