Can anyone make sense of the 2022 California requirement for plumbing fixtures?

[nealderidder]

This has always been a mess and it seems like the latest code iteration (2022) isn't helping...

Let's start with CBC 2901.1: The last line says For minimum plumbing fixture requirements, see Table 422.1 of the California Plumbing Code.

This is immediately followed by 2902.1 Minimum number of fixtures and Table 2902.1 Minimum Number of Required Plumbing fixtures.

So do I use Table 422.1 of the CPC as directed or stay here and use Table 2902.1?

The CBC doesn't give any occupant load factors but says - The number of occupants shall be determined by this code.

I guess "this code" means the CBC but there are no occupant load factors given for determining plumbing fixtures. Do I use egress loads?


Now let's start with the CPC instead. CPC 422.1 tells me to figure the minimum number required with CPC Table 422.1 but only for OSHPD projects. It also mentions and Table 4-2 and Table 4-3 that maybe also only apply to OSHPD projects?

And then I get an "Exception" that says for BSC projects (private commercial, mostly what I do) I'm told to determine occupant load from CPC Table 4-1.

CPC Table 4-1 gives me load factors which are smaller (which equates to more fixtures) that the CPC Table A we used to use (which is now gone). Were we having a crisis of people waiting too long in line at an office building to use the bathroom? When's the last time you were in an office building and saw a crowd in the bathroom?

So say I figure my number of occupants using Table A - where next? Back to Table 422.1 that is maybe only for OSHPD? This table, by the way, tells me to determine occupant load with Table A (which was in the CPC but no longer exists). Or do I go back to the CBC and use Table 2902? These tables are not duplicates and don't provide the same result.

I feel like I'm being punked. Can anyone help me make sense of this?

 

[mark handler]

Why is this residential question posted in the Commercial Building Codes


Well first of all, Note the CRC and the CPC were not written by the same organization. CPC was written by IAPMO, CRC was written by ICC.
They never match.
Second, Due to conflicts with the IAPMO/ICC generated standards, California Building Standards Commission Did not adopt PART 2.5 – 2022 CALIFORNIA RESIDENTIAL CODE Part VII Plumbing sections, and the CRC refers you to the 2022 California Plumbing Code, Title 24, Part 5.

So, it is a moot question.
So, if you use it, the AHJ may or may not allow it.

third part.
2022 CRC 1.1.7.3 Conflicts
When the requirements of this code conflict with the requirements of any other part of the California Building Standards Code, Title 24, the most restrictive requirements shall prevail.

 

[MtnArch]

Mark - I don't see where Neal referenced the Residential code in his OP.

Your post, though is very informative .. thanks!

 

[mark handler]

Mark - I don't see where Neal referenced the Residential code in his OP.

Your post, though is very informative .. thanks!

No he didn't, my bad.
BUT, CA did not adopt the Chapter 29 of the California Building Code 2022, as well.



So, it is still a moot question.

 

[nealderidder]

Mark - Yep, I see we haven't adopted CBC CH 29. That certainly helps to simplify things!


CPC 422.1 tells me to figure the minimum number required with CPC Table 422.1 but only for OSHPD projects. It also mentions and Table 4-2 and Table 4-3 that maybe also only apply to OSHPD projects? Reading this again, I see table 4-2 is noted as {OSHPD} and table 4-3 for {AGR} so probably safe to assume I can ignore those for private commercial projects.

And then I get an "Exception" that says for BSC projects (private commercial, mostly what I do) I'm told to determine occupant load from CPC Table 4-1. Seems safe to say this is where I should be for private commercial projects.

So in my case I simply go to CPC 4-1 to figure occupant load and then table 422.1 to determine the number of fixtures. Easy as pie.

Back to the ranting portion of my original post:

CPC Table 4-1 gives me load factors which are smaller (which equates to more fixtures) than the CPC Table A we used to use (which is now gone). Were we having a crisis of people waiting too long in line at an office building to use the bathroom? When's the last time you were in an office building and saw a crowd in the bathroom?

Any idea if the intention in this code cycle was to get more fixtures into commercial buildings? Load factors for warehouses went from 5,000 to 500. Makes me wonder if this was in response to Amazon warehouses that employ many more people than a traditional warehouse...
It's the office one that irks me. A factor of 200 yielded plenty of toilets. Lowering it to 150 will just take up more space for probably unnecessary fixtures.

 

[Yikes]

From Table 4-1:



Table 4-1 OLF for warehouse storage is still pretty high, about 4000 SF/occupant. It's only the labor portions of the warehouse that went to 500 SF per occupant. That's still only about 30% of the fixture counts as compared to an office use, so I don't know how your comparison to lack of office restroom queues is relevant.

 

[Paul Sweet]

You're lucky. The IBC uses one occupant per 500 SF gross for warehouses, and doesn't distinguish between storage and distribution portions.

 

[nealderidder]

View attachment 9932
View attachment 9937


View attachment 9936

From Table 4-1:
View attachment 9938


Table 4-1 OLF for warehouse storage is still pretty high, about 4000 SF/occupant. It's only the labor portions of the warehouse that went to 500 SF per occupant. That's still only about 30% of the fixture counts as compared to an office use, so I don't know how your comparison to lack of office restroom queues is relevant.

Yikes - I'm just ranting in general. In the previous code cycle a lab building would have a load factor of 200 (for business) and now it's 100. My questions is why? Was there a toilet shortage in lab buildings that was threatening public safety? The 500 load factor for distribution portions of warehouses does seem like a response to a problem (Amazon workers peeing in bottles) but was there a problem in lab buildings that needed to be solved?

 

[Andrew W]

Unless it's a state owned commercial building, you get your OLF from the CBC, not the CPC tables. BSC does not cover privately owned commercial buildings, so you can't adopt their standards (such as CPC Table 4-1). See CPC section 422.1, which states that the occupancy classification and the occupant load factors shall be "determined in accordance with the CBC"....exceptions to this are only for DSA-SS, DSA-SS/CC, and BSC projects, which, being private, yours is not.
So, for private projects, use the CBC to determine your Occupant Load, then go to CPC table 422.1 to determine the number of fixtures.

Caveats: Because of this perennial confusion, some jurisdictions have adopted their own standards for determining plumbing fixture counts. Always check with the building department first to see if they have locally adopted standards. Note that (if a local jurisdiction has, albeit errantly, adopted CPC Table 4-1 for even private projects) Table 4-1 allows you not to count accessory areas, whereas CBC table 422.1 requires you to use "gross square feet", which includes accessory areas. So if by whatever blessed turn of events you end up being allowed to use Table 4-1, while its OLFs may for some Uses be smaller than the CBC's OLFs, they are applied to smaller building areas and so may actually result in fewer fixtures being required.