Branch circuits as it pertains to bathrooms in dwellings

[John@Matros]

Hey Everybody,
So it has been brought up in discussion is the shop that when calculating minimum branch circuits in a dwelling that bathrooms should either A- each have a separate circuit, B-all bathrooms should at a minimum be circuited together or C-none of the above (bathrooms do not need separate circuits in any way by current NEC standards) This has no bearing on architectural or engineer design just minimum code standard. If there's something in there pertaining to this could you specify the article number.

Thanks All

 

[Npstewart]

A)
In my opinion each bathroom SHOULD have its own circuit mainly because hair dryers are energy hogs and some require 1800 watts of power.

B)
It is in the opinion of the NEC that the bathroom receptacle circuit can also feed other bathroom receptacles in the dwelling unit but ONLY receptacles in the other bathrooms. 210.11(C)(3)

C) See above section 210.11(C)(3)

 

[cadpoint]

Bathroom has it's own listing in the Index, I'd suggest a total review by all parties concerned.

I'm looking @ 2011 NFPA 70, I don't want to argue the merits per items as stated in the choices of A, B or C.

My belief is; like the aguement, is that the Code has changed over time due to the nature of your question.

I'll default to "Charlie's rule". HERE

 

[charlie b]

. . . when calculating minimum branch circuits in a dwelling . . . .

What is the intent here? Are you trying to "calculate" the minimum number of circuits you could possibly install, and still meet NEC minimum requirements? Or are you trying to "decide" how you would choose to circuit a dwelling unit, in order to achieve a happy homeowner?

With regard to bathroom circuits, given a home with at least two bathooms, the absolute minimum number is two: One to serve all receptacles (and nothing but receptacles) in all the bathrooms in the house, and the other to serve any lights, heaters, or other outlets. That later circuit can be shared with other rooms.

That said, if I were designing the house electrical system, I would choose to have a dedicated circuit for each bathroom, and it would serve all outlets in that bathoom. So my minimum number of circuits would equal the number of bathrooms.

 

[John@Matros]

I am in full agreement as far as what is proper in regards to a quality job for the client, we were speaking strictly minimum code standards just a matter of curiosity not real life application.

 

[raider1]

The minimum required by code would be B. All the receptacles in all the bathrooms in the home can be on 1 20 amp circuit.

Chris

 

[Dennis Alwon]

I agree with Chris. I prefer to keep the master bath recep. separate from the others however, per code, you can all receptacles in all baths on one circuit.

 

[charlie b]

Keep in mind that the original question is talking about branch circuits that serve bathrooms. There are more outlets than just receptacles to be considered.

 

[Dennis Alwon]

I think the op is looking for the minimum number of branch circuits for a dwelling of a certain size. The lights etc in a bath can be on with other circuits.

 

[raider1]

Keep in mind that the original question is talking about branch circuits that serve bathrooms. There are more outlets than just receptacles to be considered.

Yes, but no additional branch circuits are required to supply the lights or fans in a bathroom. They can be supplied by a general purpose lighting and receptacle circuit such as a bedroom circuit.

Chris

 

[John@Matros]

Thanks for the infor guys, much appreciated.

 

[Rutherford]

So two bathrooms, two branch circuits

So two bathrooms, two branch circuits

I interpret my NY 2010 Residential Code, which has most if not all of NEC 2008 embedded, to mean:

For a two-bathroom house, one can put the receptacles for both baths on one branch circuit, and each recep within defined "wet" zones must be GFCI-protected. One can then put all non-receptacle outlets (lights, fans) on a second circuit.

Alternatively, one can put each bathroom, all outlets in each, on two separate branch circuits, again paying attention to the GFCI requirements for certain receptacles.

But that is my interpretation of what I've read.

The upside of the lights-and-fans-as-one for both bathrooms, and the receps on the other, is that one can generally use 14-2 wire for the lighting-and-fans circuit. Far easier makeup, as compared to the 12-2 used for the recep circuit.

 

[LarryFine]

You've got it, and welcome to the forum!

I think the single-circuit-for-the-entire-bathroom allowance was made for new bathroom additions.