CALGreen Plumbing Fixture Flow Rates

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A plumbing fixture can look correct, fit the finish schedule, and still be the wrong fixture for the job because the flow number on its product data does not match the requirement that applies at that location. That is the central decision in this lesson. I am not asking you to design a plumbing system. I am asking you to act like the General B contractor who stops the wrong product before it gets ordered, installed, and discovered at final inspection.

The 2 units do different jobs. Gallons per flush applies to fixtures that discharge a measured volume during a cycle, such as water closets and urinals. Gallons per minute applies to fixtures that flow continuously while they are open, such as showerheads and faucets. The listed test pressure also matters. A faucet rating without the pressure condition is an incomplete comparison, because the source requirements pair the permitted flow with a stated pressure.

The practical consequence is straightforward. A subcontractor may submit a model that is legal somewhere else, or acceptable under a different occupancy, but that does not establish compliance on this project. I need the exact model, the exact flow or flush rating, the location where it will be installed, the approved project requirements, and the local rules. The box is not the authority. The cut sheet is evidence, and the applicable code and local adoption control the decision.

The General B role begins at the submittal gate. I compare the fixture schedule and approved plans with the manufacturer's product data before procurement. I verify whether the fixture serves a dwelling unit, a public or common area, or a nonresidential space. I check whether the rating is expressed in gallons per flush, gallons per minute, or gallons per cycle. I also check the pressure attached to a flow rating.

That review sounds administrative, but it protects physical work. Once a wrong faucet is installed across several restrooms, correction can involve replacement fixtures, changed aerators that may not be acceptable for the listed product, reopened finish work, another inspection, and schedule delay. The source material specifically keeps the General B boundary on verification and coordination. It does not turn the General B contractor into the plumbing designer.

I also want you to separate 3 questions that contractors sometimes blend together. What is the statewide limit for a new installation? Does an existing fixture meet the Civil Code definition of noncompliant? Has the local jurisdiction adopted a reach code that is stricter than the statewide baseline? Those questions can produce different numbers for the same general fixture category. Treating them as 1 question is how a familiar number gets used in the wrong place.

The statewide baseline reference starts with water closets. Newly installed residential and nonresidential water closets must not exceed an effective flush volume of 1.28 gallons per flush. For a dual-flush toilet, the effective flush volume is a composite average based on 2 reduced flushes and 1 full flush. The important supervision point is that I verify the listed effective flush volume, not merely the marketing label or the larger of the 2 buttons.

Urinals divide by mounting type. A wall-mounted urinal must not exceed 0.125 gallons per flush. Other urinals, including floor-mounted models, must not exceed 0.5 gallons per flush. That difference is easy to miss because both products are called urinals, but the source requirement does not give them the same ceiling.

A single showerhead must not exceed 1.8 gallons per minute at 80 pounds per square inch. Residential lavatory faucets must not exceed 1.2 gallons per minute at 60 pounds per square inch. They also have a minimum flow of 0.8 gallons per minute at 20 pounds per square inch. Nonresidential lavatory faucets are capped much lower, at 0.5 gallons per minute at 60 pounds per square inch.

Kitchen faucets have a baseline maximum of 1.8 gallons per minute at 60 pounds per square inch. A compliant kitchen faucet may temporarily increase to 2.2 gallons per minute, but it must default back to 1.8 after shutoff or standard operation. Metering faucets, whether residential or nonresidential, must not deliver more than 0.2 gallons per cycle.

I use this reference as a submittal screen, not as permission to ignore the rest of the project. A model can satisfy the statewide baseline and still be rejected where a local reach code establishes a stricter requirement. A model can also have the correct flow but be wrong for the listed use or location. The number is necessary, but the number alone is not the whole approval.

The water closet number that matters for a new installation is 1.28 gallons per flush. The number that defines an older toilet as noncompliant under California Civil Code is different. That threshold is more than 1.6 gallons per flush. I will return to the retrofit rule shortly, but I want to plant the distinction now because it is 1 of the most important memory connections in the lesson.

Think of 1.6 as the trigger line for identifying an existing high-use toilet under the retrofit law. Think of 1.28 as the ceiling for the replacement product under the current new-installation standard described in the source report. A 1.6 gallon toilet may sit at the legal definition threshold rather than above it, but that does not make 1.6 the correct specification for a newly installed replacement.

The same kind of distinction appears with urinals. The Civil Code definition identifies a urinal using more than 1 gallon per flush as noncompliant. The current new-installation ceilings are far lower: 0.125 for a wall-mounted urinal and 0.5 for other urinals. I do not carry the old-fixture trigger into the new-fixture purchase decision.

Dual-flush toilets add 1 more detail. The code calculation described in the source uses 2 reduced flushes and 1 full flush to establish the effective flush volume. I do not assume the full-flush button by itself tells me whether the model qualifies. I verify the manufacturer's listed effective flush volume and supporting product data.

A custom shower is where the flow rule becomes a coordination rule. The 1.8 gallons per minute limit at 80 pounds per square inch does not automatically multiply by the number of outlets in the enclosure. When multiple showerheads are controlled by a single valve, the combined flow of all outlets that can operate together must not exceed 1.8 gallons per minute. The alternative described in the source is a design that allows only 1 outlet to operate at a time.

That means a handheld wand, an overhead head, and body sprays cannot each claim a separate 1.8 gallon budget when the controls allow simultaneous use from the same valve arrangement. The source material treats those shower outlets as part of the combined condition. The supervision question is not only, what does each head say on its box? The better question is, what can the user turn on at the same time?

Suppose a client selects an overhead showerhead, a handheld wand, and several body sprays. The plumbing submittal shows controls that allow all outlets to run together. If their combined listed flow exceeds 1.8 gallons per minute at the stated pressure, approving each outlet separately would miss the governing condition. I would return the submittal for a compliant configuration, such as controls that physically limit operation to 1 outlet at a time, subject to the approved design and manufacturer requirements.

That consequence chain is worth remembering. Separate product ratings can look acceptable. Simultaneous operation creates a combined rate. The combined rate exceeds the allowed ceiling. The installed configuration then conflicts with the requirement even though every individual trim piece looked efficient on its own. The simplest memory line is this: in a multi-outlet shower, count what can run together.

I would not solve that conflict by improvising pipe sizes, altering certified components, or inventing a field restriction. Those decisions belong with the appropriate design professional, plumbing contractor, approved documents, and listed products. My job as the General B contractor is to catch the coordination issue early and make sure the approved solution is reflected in the submittals and installation.

Lavatory faucets require an occupancy distinction. Inside a residential dwelling unit, the maximum is 1.2 gallons per minute at 60 pounds per square inch, with the stated minimum of 0.8 gallons per minute at 20 pounds per square inch. In a nonresidential lavatory, the maximum is 0.5 gallons per minute at 60 pounds per square inch.

The common mistake is to hear the word lavatory and remember only 1 faucet number. I attach the location to the number. Residential dwelling lavatory: 1.2. Nonresidential lavatory: 0.5. In a residential development, a public or common-use restroom may be governed by the nonresidential value for that location, so I do not order every bathroom faucet from the dwelling-unit schedule.

Kitchen faucets are different again. The normal maximum is 1.8 gallons per minute at 60 pounds per square inch. The source permits a temporary increase to 2.2 gallons per minute when the fixture automatically returns to the 1.8 rate. The word temporary matters. A faucet that simply stays at 2.2 during ordinary operation does not fit that exception.

Metering faucets are measured by the amount delivered per cycle rather than by a continuous gallons-per-minute rating. The maximum is 0.2 gallons per cycle. That unit tells me what to look for on the cut sheet. Comparing a gallons-per-cycle requirement to a gallons-per-minute label without understanding the product's operation would be an apples-to-oranges review.

Here is the physical connection that makes the numbers easier to organize. A flush fixture releases a defined volume, so I look for gallons per flush. A continuously opened outlet is evaluated by flow over time, so I look for gallons per minute and the test pressure. A metering faucet shuts itself after a controlled dose, so I look for gallons per cycle. The unit follows how the fixture delivers water.

The retrofit rules create the most important distinction in the episode: the definition of an existing noncompliant fixture is not the same as the specification for the new replacement fixture.

Under California Civil Code Section 1101, a noncompliant plumbing fixture includes a toilet using more than 1.6 gallons per flush, a urinal using more than 1 gallon per flush, a showerhead flowing at more than 2.5 gallons per minute, or an interior faucet flowing at more than 2.2 gallons per minute. Those values identify existing fixtures that cross the statutory threshold.

When replacement is required, I do not shop to those old thresholds. I verify the replacement against the current requirement that applies to the new fixture and its location. For example, the source report pairs the older toilet trigger of more than 1.6 gallons per flush with a current replacement ceiling of 1.28 gallons per flush. The trigger tells me what must go. The new-installation standard tells me what may go back.

The source report states that permitted alterations or improvements to a single-family property built and available for use on or before January 1, 1994, trigger replacement of all noncompliant fixtures as a condition of final permit approval. The fixture does not have to sit inside the remodeled room. That is the estimating trap.

Imagine a contractor pricing a permitted bedroom expansion on a single-family home built in 1988. The guest bathroom is outside the addition, but it still has an older toilet rated at 3.5 gallons per flush and a showerhead rated at 3 gallons per minute. Both exceed the statutory noncompliant thresholds described in the source. If the contractor ignores them because the bathroom is outside the new bedroom work, the project can reach final inspection with unplanned replacement work still required.

I would address that during the site walk and estimate. I would identify existing fixture ratings where they can be verified, note any fixtures that require confirmation, define the expected replacement scope, and coordinate the permit condition with the local building department. That protects the owner from a surprise and protects the contractor from absorbing work that should have been included.

For multifamily and commercial properties, the source report describes different triggers and scope. An addition that increases floor area by more than 10% can require replacement of noncompliant fixtures throughout the building. For an alteration or improvement with a total construction cost above $150,000, the report states that the required replacements are the noncompliant fixtures serving the specific area of improvement. Because project facts and local administration matter, I would verify the applicable scope with the building department rather than treating a summary as project-specific legal advice.

This is also where precise language matters. More than 1.6 is not the same as 1.6 or more. More than 2.5 is not the same as 2.5 or more. The source uses threshold language, and I preserve it. On a real project, I also verify the actual fixture marking, documentation, permit scope, property date, and local interpretation before making a contractual or compliance decision.

A statewide baseline is the starting point, not always the finish line. CALGreen includes voluntary Tier 1 and Tier 2 measures. A local jurisdiction may adopt those measures as mandatory reach codes. The source report describes Tier 1 as a 12% reduction and Tier 2 as a 20% reduction in potable water use.

The practical lesson is not to memorize a list of cities, because local ordinances can change. The practical lesson is to check the current local adoption before approving fixture submittals. The authority having jurisdiction may require a stricter value than the statewide baseline shown on a general reference sheet.

The source gives a Tier 1 prescriptive example for nonresidential fixtures. A nonresidential lavatory faucet that meets the statewide 0.5 gallon-per-minute baseline may still be too high where the adopted Tier 1 value is 0.35 gallons per minute. A kitchen faucet that meets the statewide 1.8 baseline may need to be limited to 1.6 gallons per minute under that prescriptive path.

That is why a label saying California compliant is not enough for my project file. I need compliance with the actual jurisdiction, code cycle, occupancy, and approved plans. The local check belongs before purchase, not after the inspector reads the model number.

My fixture submittal review follows a repeatable sequence. I identify the exact installation location and whether it is residential, common-use, or nonresidential. I read the model-specific product data. I match the unit to the fixture type. I verify the flow or flush value and the stated test pressure. I compare that information with the approved project requirements and statewide baseline. I then check local amendments or reach-code requirements before I approve procurement.

For replacement work, I add another layer. I determine whether the property date and permit scope bring the Civil Code retrofit provisions into play. I separate the threshold used to identify an existing noncompliant fixture from the limit for the new replacement. I document the existing condition, the selected replacement, and any confirmation received from the local building department.

At inspection, clear records matter. The installed model should match the approved submittal. The rating should be readable in the product documentation. A multi-outlet shower should operate in the approved configuration. A kitchen override should return to the normal flow as required. Common-area lavatories should not quietly receive residential fixtures because the finish package looked the same.

I want you to hold onto 5 memory anchors. Toilets for new installation: 1.28 gallons per flush. Showerheads: 1.8 gallons per minute at 80 pounds per square inch, counting what can run together. Residential lavatory: 1.2 at 60. Nonresidential lavatory: 0.5 at 60. Existing-fixture retrofit thresholds are a separate set of numbers and never become the shopping list for new fixtures.

The deeper pattern is supervision through distinctions. Flush volume is not flow rate. Residential is not nonresidential. An existing-fixture trigger is not a new-installation ceiling. Statewide baseline is not necessarily the local requirement. 1 efficient showerhead is not proof that a multi-outlet configuration is compliant. When I keep those distinctions separate, the numbers stop feeling like an unrelated pile.

I made an audio practice quiz for this specific episode on CALGreen plumbing fixture flow rates. It is audio-based. I read the questions aloud, and you answer by tapping, because I know a lot of your studying happens while you are driving, working, or moving between jobs. Go to the description below this video. You will see a link that says PassTheCSLB. Tap it. It will take you straight there. Comment below with any questions about anything I covered. Subscribe so I can help you stay on track through every episode until you get your license. I am rooting for you, and I want you to move through this process prepared, steady, and confident.