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Single Occ restrooms in lieu of multi

Y

Yikes

SAWHORSE
Joined
Nov 2, 2009
Messages
4,200
Location
Southern California
I have an apartment complex with a community room for 97 occupants. There’s a possibility that outside/visiting groups may also use the community room.
My client is considered providing all single-occupancy restrooms in lieu of multi-user. Can I apply the fixture count as shown below per the California Plumbing Code?

Conventional multi user restrooms per CPC 422.1 for 48 females and 48 males:

Female restroom: 2 toilets, 1 lavatory, 1 diaper changing table; Male restroom: 1 toilet, 1 urinal, 1 lavatory, 1 diaper changing table
vs.
All unisex, all single occupancy restrooms:
Restroom 1: 1 toilet, 1 lavatory
Restroom 2: 1 toilet, 1 lavatory, 1 diaper changing table
Restroom 3: 1 toilet, 1 lavatory, 1 urinal
 
arwat23 said:
I do all unisex single-user for most of my projects. Only one jurisdiction has ever questioned it before, and it'll explicitly be allowed in the 2025 CPC.

View attachment 16534
Click to expand...
I guess my question has to do with proposing the actual number of fixtures, but they are in 3 bathrooms, not 4.

So in the multi-user restrooms per CPC configuration, 2 men and 2 women could be using toilets or urinals at one time.
In the single user version, only 3 people could use them at one time (because I’ve put a toilet+urinal in one single-user restroom.. Does that still meet code?

I really want it to, because California regs for requiring diaper changing tables make the multi-user, separate sex restrooms too big for the available space.
 
Last edited:
Yikes said:
I guess my question has to do with proposing the actual number of fixtures, but they are in 3 bathrooms, not 4.

So in the multi-user restrooms per CPC configuration, 2 men and 2 women could be using toilets or urinals at one time.
In the single user version, only 3 people could use them at one time (because I’ve put a toilet+urinal in one single-user restroom.. Does that still meet code?
Click to expand...

Obviously not.

Why put a urinal in a single-occupant toilet room? I've seen a lot of single-occupant toilet rooms, all around the world (not just in the U.S.). I can't recall ever seeing one with a water closet and a urinal.
 
Yankee Chronicler said:
Obviously not.

Why put a urinal in a single-occupant toilet room? I've seen a lot of single-occupant toilet rooms, all around the world (not just in the U.S.). I can't recall ever seeing one with a water closet and a urinal.
Click to expand...
California code allows a single occupancy restroom to have both a urinal and a WC, and it is not uncommon here.
 
Yankee Chronicler said:
Why put a urinal in a single-occupant toilet room? I've seen a lot of single-occupant toilet rooms, all around the world (not just in the U.S.). I can't recall ever seeing one with a water closet and a urinal.
Click to expand...
Some possible reasons:

Th urinal is most likely using less water than the water closet.

With a urinal, users do not need to lift the toilet seat.
 
To further explain my space constraints imposed by unique California regulations:
California has a Health and Safety Code 118506 that mandates installation of a baby diaper changing table in both men’s and women’s restrooms, or in a gender neutral restroom, that serves assembly and other public uses of 60 or more occupants.
This may not seem like a big deal if you are designing outside of California: hey just put a fold-down changing table in the huge accessible WC compartment.
But no, California also has 11B-226.4 which prohibits the table from being located in the accessible compartment in a multi-user facility.

Furthermore, many CASps will say that the table when folded down cannot obstruct required circulation clearances, and its ends must have a guard or other detectable warning for the visually impaired.
Now the changing table basically needs as much space as a sink, urinal or other fixture.
 
Yikes said:
I guess my question has to do with proposing the actual number of fixtures, but they are in 3 bathrooms, not 4.

So in the multi-user restrooms per CPC configuration, 2 men and 2 women could be using toilets or urinals at one time.
In the single user version, only 3 people could use them at one time (because I’ve put a toilet+urinal in one single-user restroom.. Does that still meet code?
Click to expand...
As long as you hit the minimum required number of fixtures, you're good. A urinal in a single-user restroom still counts towards the total even though one person will occupy the room with both fixtures.
 
Yikes said:
California code allows a single occupancy restroom to have both a urinal and a WC, and it is not uncommon here.
Click to expand...

California may allow it, but IMHO it's a waste of space. Unless the fixtures inside are separated by toilet partitions, the toilet room can't be counted as two fixtures, and installing partitions would require making the space even larger. So why do it? It makes no sense from a space utilization perspective. Regardless of whether or not there's a urinal in there, a single-occupant toilet room only counts as one fixture.
 
arwat23 said:
As long as you hit the minimum required number of fixtures, you're good. A urinal in a single-user restroom still counts towards the total even though one person will occupy the room with both fixtures.
Click to expand...

I have to disagree ... but I'm not in California, and California may view things differently.

[Edit to add} I forgot that California uses the UPC, not the IPC. Therefore, California probably is different.
 
The IPC and UPC are completely different. Not apples to oranges, more like apples to steak. And it not just CA, there are several holdouts:
1758152514327.png
As @Yikes stated, it's not uncommon. It's kind of funny. If you look for them, you'll find reports "showing" why one or the other is better. In reality, it's what you're familiar with. To us there are things that IPC allows that seem crazy. To you, a single occupant bathroom with both a toilet and a urinal seems crazy.

Check out this analysis, not sure I believe it, but it's interesting:
www.linkedin.com

IPC vs UPC: Engineering Analysis of Plumbing Code Compliance Systems

Executive Summary The choice between the International Plumbing Code (IPC) and Uniform Plumbing Code (UPC) significantly impacts engineering design parameters, construction costs, and system performance. Research indicates that regional authorities increasingly accept UPC specifications due to super
www.linkedin.com www.linkedin.com
 
Yankee Chronicler said:
I have to disagree ... but I'm not in California, and California may view things differently.

[Edit to add} I forgot that California uses the UPC, not the IPC. Therefore, California probably is different.
Click to expand...
It wouldn't be California if we did things the way the rest of the century did.

The current version of our plumbing code (2022 CPC / 2021 UPC) technically requires separate facilities instead of unisex with few exceptions (CPC 422.2). That's never been enforced as long as I've been working here. Only one jurisdiction pushed back on it, and they gave up when I explained why we had 8 single-user unisex restrooms (healthcare facility, client request). All the jurisdictions usually care about is hitting the fixture count. Seems they finally realized that and changed code the 2024 UPC / 2025 CPC to include language that explicitly allows this.

Hell, they don't even enforce the urinal requirement when we use single-user unisex restroom since CPC Table 422.1, note 6 allows AHJs to modify what's required. The only time we had push back on not having a urinal, we said "all the restrooms are single-user unisex restroom. We've received complaints from women about feeling uncomfortable when there's a urinal in those rooms (which is true, clients have received complaints). Since all the rooms can only be used by one person, we removed all urinals to make visitors feel more comfortable." Approved, no other questions asked.
 
Yikes said:
I have an apartment complex with a community room for 97 occupants. There’s a possibility that outside/visiting groups may also use the community room.
My client is considered providing all single-occupancy restrooms in lieu of multi-user. Can I apply the fixture count as shown below per the California Plumbing Code?

Conventional multi user restrooms per CPC 422.1 for 48 females and 48 males:

Female restroom: 2 toilets, 1 lavatory, 1 diaper changing table; Male restroom: 1 toilet, 1 urinal, 1 lavatory, 1 diaper changing table
vs.
All unisex, all single occupancy restrooms:
Restroom 1: 1 toilet, 1 lavatory
Restroom 2: 1 toilet, 1 lavatory, 1 diaper changing table
Restroom 3: 1 toilet, 1 lavatory, 1 urinal
Click to expand...
Some jurisdictions will allow an alternate occupant load analysis using CPC Table 4-1 occupant load factors. Would that change anything for you?
 
Here's what the 2025 CPC (eff. Jan 1, 2026) looks like:

422.2 Separate Facilities. Separate toilet facilities shall be provided for each sex.
Exceptions [Not adopted for OSHPD 1, 2, 3, 4 & 5):
(1) Residential installations.
(2) In occupancies with a total occupant load of 10 or less, including customers and employees, one toilet facility, designed for use by no more than one person at a time, shall be permitted for use by both sexes.
(3) In business and mercantile occupancies with a total occupant load of 50 or less including customers and employees, one toilet facility, designed for use by no more than one person at a time, shall be permitted for use by both sexes.
(4) Separate facilities shall not be required where rooms have fixtures designed for use by both sexes and the water closets are installed in privacy compartments. Urinals shall be located in a privacy compartment [BSC & DSA-SS], as defined, or separate private area and be visually separated from the remainder of the room.
Water closet and urinal compartments shall comply with sections 422.6 and 422.7 respectively.

422.2.1 Single Use Facilities. Single use toilet facilities, bathing facilities, and family or assisted use toilet facilities shall be identified with signage indicating use by either sex.

422.2.2 Family or Assisted-Use Toilet Facilities. Where a separate toilet facility is required for each sex, and each toilet facility is required to have only one water closet, two family or assisted-use toilet facilities shall be permitted in place of the required separate toilet facilities.

It's weird that the [BSC & DSA-SS] indicator is in the middle of a sentence, not sure if that's a typo. They usually issue an Errata in October to fix typos or other errors, so I'll be looking at that again.
 
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