running new wire from bathroom to circuit box
#1
Member
Thread Starter
Join Date: Oct 2012
Location: usa
Posts: 91
Received 0 Votes
on
0 Posts
running new wire from bathroom to circuit box
Current layout in bathroom:
1. old switch and outlet
2. light in ceiling
3. when running hair dryer in BR and iron in adjacent room, the breaker will trip.
Since I'm remodeling the bathroom all walls are exposed at this point.
I would like to by pass the existing wire and run a new wire to the basement circuit box. I'm think I would have to remove the current switch and outlet and combine the two wires in a junction box?
I need to install a GFI outlet and single switch.
I will still have a light in the BR and additionally need to install a ceiling vent/heater.
Not sure how big a project this is to take on?
Not sure what size wire to use (12/2 romex?), what size circuit breaker 20a?
and how to run the wires from the box in the BR to the light and vent.
any thoughts would be great.
1. old switch and outlet
2. light in ceiling
3. when running hair dryer in BR and iron in adjacent room, the breaker will trip.
Since I'm remodeling the bathroom all walls are exposed at this point.
I would like to by pass the existing wire and run a new wire to the basement circuit box. I'm think I would have to remove the current switch and outlet and combine the two wires in a junction box?
I need to install a GFI outlet and single switch.
I will still have a light in the BR and additionally need to install a ceiling vent/heater.
Not sure how big a project this is to take on?
Not sure what size wire to use (12/2 romex?), what size circuit breaker 20a?
and how to run the wires from the box in the BR to the light and vent.
any thoughts would be great.

#2
Suggest running a 12-2 cable with a 20 amp breaker for the bathroom receptacle(s). A ground fault circuit interrupter can be the first receptacle and that can daisy chain to additional recpetacles.
Lights and exhaust fan in the same bathroom can be hooked into this new circuit but any 14 gauge wiring has to be upgraded to 12 gauge. Or the lights can stay on the old circuit.
Run another circuit if you are installing a fan/heater, so this does not compete with hair dryers and other plug in items.
Also a good idea to run yet a few more 12-2's for future use in other rooms. You will have to be prepared to have them end at junction boxes with exposed covers on the wall if you did not have a crystal ball to help decide how long to make them before curling them up in the wall. Do not connect them to any breakers p[rior to uncurling the far ends and creating your future circuits.
Lights and exhaust fan in the same bathroom can be hooked into this new circuit but any 14 gauge wiring has to be upgraded to 12 gauge. Or the lights can stay on the old circuit.
Run another circuit if you are installing a fan/heater, so this does not compete with hair dryers and other plug in items.
Also a good idea to run yet a few more 12-2's for future use in other rooms. You will have to be prepared to have them end at junction boxes with exposed covers on the wall if you did not have a crystal ball to help decide how long to make them before curling them up in the wall. Do not connect them to any breakers p[rior to uncurling the far ends and creating your future circuits.
#3
Member
Thread Starter
Join Date: Oct 2012
Location: usa
Posts: 91
Received 0 Votes
on
0 Posts
thanks for the reply Allan.
i was using the wrong terms. i'm installing an exhaust fan heater combo, not vent.
1. are you suggesting that i run one 12/2 to the GFI, light switch and light and a second 12/2 for the exhaust fan. connecting both to the circuit box ?
2. also, i don't plan on using the existing wires in the bathroom, but i need those wires to have electric in adjacent room. when i remove the outlet and switch, do i just splice the wires together and put them in the box too ?
i was using the wrong terms. i'm installing an exhaust fan heater combo, not vent.
1. are you suggesting that i run one 12/2 to the GFI, light switch and light and a second 12/2 for the exhaust fan. connecting both to the circuit box ?
2. also, i don't plan on using the existing wires in the bathroom, but i need those wires to have electric in adjacent room. when i remove the outlet and switch, do i just splice the wires together and put them in the box too ?
#4
Lights can use the existing circuit and you can run a new circuit for receptacles. If the existing cables do not have grounds they can not be extended. Lights are best not on a GFCI. Vent/Exhaust fans also do not normally need GFCI protection.
Last edited by ray2047; 02-14-17 at 10:03 PM.
#5
i'm installing an exhaust fan - heater combo
Depending on the heater size it may require its own dedicated circuit.
#7
Member
Thread Starter
Join Date: Oct 2012
Location: usa
Posts: 91
Received 0 Votes
on
0 Posts
running the wire from 2nd floor
this is pretty dumb question but, i found direct access to basement with a blumb line next to main drain line direct to basement floor.
i'm assuming no issues with running this line via the drain?

#9
Member
Thread Starter
Join Date: Oct 2012
Location: usa
Posts: 91
Received 0 Votes
on
0 Posts
just to be clear is this the circuit breaker and GFI that i would need?
it looks identical to the ones i have in the box
Square D QO 20 Amp Single-Pole Circuit Breaker-QO120CP - The Home Depot
Leviton 20 Amp 125-Volt Duplex SmarTest Self-Test SmartlockPro Tamper Resistant GFCI Outlet, White-R92-GFTR2-0KW - The Home Depot
Also which side of the box to i attach the white and ground wires.
I see the right side has a green screw at the top?

it looks identical to the ones i have in the box
Square D QO 20 Amp Single-Pole Circuit Breaker-QO120CP - The Home Depot
Leviton 20 Amp 125-Volt Duplex SmarTest Self-Test SmartlockPro Tamper Resistant GFCI Outlet, White-R92-GFTR2-0KW - The Home Depot
Also which side of the box to i attach the white and ground wires.
I see the right side has a green screw at the top?


#10
Also which side of the box to i attach the white and ground wires.
Neutral must be in its own hole. 2-3 ground wires can typically share one hole (if needed).
#11
Member
Thread Starter
Join Date: Oct 2012
Location: usa
Posts: 91
Received 0 Votes
on
0 Posts
connect 3 wire cable and 4 wire cable

three questions.
1. how would i splice these together?
2. the original box was 56" and i want to lower it to around 50". would i have to put these wires in a junction box and run another wire to the new box at 50"
3. how would i hook these wires up to a new light switch?

#12
If the wires do not reach the new box then you will need to leave the old box in place with an exposed cover and run a cable or conduit to a new box at the desired location.
A dimmer may or may not work where a regular switch used to be dependingt on the wiring at that location.
A green wire is for grounding and is connected to a cluster of bare (or other green) wires in the box. The other two wires would be connected in the same way as the old switch was connected.
Label all wires before disconnectig them from the old light or fan or switch.
A dimmer may or may not work where a regular switch used to be dependingt on the wiring at that location.
A green wire is for grounding and is connected to a cluster of bare (or other green) wires in the box. The other two wires would be connected in the same way as the old switch was connected.
Label all wires before disconnectig them from the old light or fan or switch.
#13
just to be clear is this the circuit breaker and GFI that i would need?
it looks identical to the ones i have in the box
Square D QO 20 Amp Single-Pole Circuit Breaker-QO120CP - The Home Depot
Leviton 20 Amp 125-Volt Duplex SmarTest Self-Test SmartlockPro Tamper Resistant GFCI Outlet, White-R92-GFTR2-0KW - The Home Depot
it looks identical to the ones i have in the box
Square D QO 20 Amp Single-Pole Circuit Breaker-QO120CP - The Home Depot
Leviton 20 Amp 125-Volt Duplex SmarTest Self-Test SmartlockPro Tamper Resistant GFCI Outlet, White-R92-GFTR2-0KW - The Home Depot
Leviton 15 Amp 125-Volt Self-Test Tamper Resistant GFCI Outlet - White-R99-GFTR1-RKW - The Home Depot