I'm wiring a 2-story addition to my house, each floor of the addition is a bathroom and closet.
I will be running two receptacle circuits, one for each bathroom, each protected by a GFCI receptacle, with all other receptacles in the room on the LOAD side. This will include the exhaust fan/light combo (with associated switches wired via a short section of 12/3).
I was planning on running an individual lighting circuit to each bathroom and an additional lighting/receptacle circuit to be shared by both closets.
This would get me a total of 5 circuits:
- Downstairs bath receptacles (including vent fan/light combo)
- Downstairs bath lights
- Upstairs bath receptacles (including vent fan/light combo)
- Upstairs bath lights
- Upstairs & downstairs receptacles & lights
Is there any distinct advantage to having the bathroom lighting (circuits 2 & 4) separated I had planned, or would I be just as well served by combining those into a single lighting circuit?
A GFCI trip would only kill the outlets, leaving lights on. A lighting circuit breaker trip would, potentially leave both rooms in the dark, however, all wiring will be 12/2 on 20A breakers and all lights (a total of about 15 bulbs) will be LED. Something would have to go seriously wrong for us to ever come close to overloading a single lighting circuit for both bathrooms.
I do have a brand new, 40-space panel with about 35 spaces free, so circuits are not at a premium at the moment. I'm just trying to determine if I need to use an extra circuit in this case. Of course, if NEC (we're currently on 2008) says that each room must be on its own lighting circuit, I'll stick with the current (pun intended) plan.
This could easily devolve into opinion-based territory. I'm looking to avoid that by looking for A) code reasons for having two circuits, and/or B) practical reasons for keeping them separated. At this point in time, saving the extra copper by not having to make an extra home run is very appealing.