Are you wondering how to wire a bathroom fan and light to separate switches?
Sometimes you just want the light on a separate switch so you can turn it on without making any sound.
The biggest thing to consider is that you may need to route a new wiring cable from the bathroom fan to the wall switch.
This wiring is known as a '12/3' cable and includes two hot wires.
In this guide, you will discover:
- Connecting the hots, neutrals, and grounds together
- Fishing the new 12/3 cable through the ceiling or wall
- How to connect the new wiring to a double toggle wall switch
Keep reading to learn the supplies that you'll need, and our step-by-step guide on how to do the wiring.
What You Need To Know About Wiring A Double Switch Bathroom Fan And Light
Probably the most important thing to know about wiring a bath fan and light on separate switches is that you will need to run a new wiring cable from the bathroom fan to the existing switch.
If you just had a normal fan with no light or heater, then you just have 12/2 wiring which includes a single hot, a single neutral, and a ground.
But if you want to wire a fan and light to separate switches, you will need two hots running from the bath fan to the wall switch. 12/3 cable includes two hots, one neutral, and one ground.
Use A Licensed Electrician
For most cases, homeowners should call in a licensed electrician to do this job. Your local city or county code will almost certainly require it as well.
There is a risk of electrical shock or even starting a fire if the wiring is done incorrectly.
Electricians have a lot of tricks and methods for geting new wiring cable through a wall or ceiling that the average homeowner may not know.
Read Also >> How To Install A Bathroom Fan On The First Floor?
Supplies You'll Need To Wire An Exhaust Fan And Light On Separate Switches
- 12/3 Cable - The bathroom fan needs 12/3 wiring from the housing to the switch in order to for it to use two separate switches. 12/3 wiring includes two hots (black/red), one neutral (white), and one ground (green/copper).
- Double Toggle Wall Switch - These double switches will have two toggles so you can separately control the light and fan.
- Wire Nuts - You will need a way to connect the hots, neutrals, and grounds together. You can use the tried and true wire nut. But the easiest way is to use modern quick connects or Wago lever nuts.
- Fish Tape - A fish tape set will be highly useful if you need to get a new 12/3 cable from the bath fan to the wall switch. Fish tape is flexible and will help you route the wiring through the ceiling or wall.
- Electrical Tape - You want to use one or two wraps of standard electrical tape around the wall switch to secure the connections.
How To Wire A Bathroom Fan And Light On Separate Switches (13-Step Guide)
- Turn Off Power at Panel and Verify It's Off
- Remove Old 12/2 Wiring From Bath Fan
- Connecting the New Ground to Housing
- Connect the Hot Wires At Housing
- Connect the Neutrals At Housing
- Push Wiring Into Housing And Secure Cover
- Route the New 12/3 Cable to the Double Switch
- Connect the Grounds At Switch
- Connect The Two Neutrals At Switch
- Connect Ground Pigtail To Switch Terminal
- Connect Power to the Common Terminal
- Connect Hot Wires to the Switch Bronze Terminals
- Wrap With Electrical Tape
- Secure the Double Switch and Re-install Cover Plate
Step 1 – Turn Off Power at Panel and Verify It's Off
As with any wiring job, the first step is to turn off the power at the panel box.
We also recommend that you verify the power is off to the exhaust fan by using a non-contact voltage tester.
A non-contact voltage tester can detect whether there is power by just getting close to the wire or double switch. If there is still power, it will beep or light up (and some do both).
Step 2 – Remove Old 12/2 Wiring From Bath Fan
At the bath fan housing, remove the wiring cover plate, and disconnect the existing 12/2 wiring that goes into the housing.
The ground wire is usually connected to the cover plate grounding terminal.
The two hots (one for the fan and one for the light) will be connected to the old 12/2 cable either through wire nuts or quick connects. Simply disconnect the wiring.
Read Also >> How To Vent A Bathroom Fan Through The Wall?
Step 3 – Connect the New Ground to Housing
Connect the ground from the new 12/3 cable to the bath fan housing.
There will usually be a ground terminal on the wiring cover. Simply hook and crimp the ground wire around the terminal in a clockwise fashion, and then tighten the screw.
Step 4 – Connect the Hot Wires At Housing
Connect the new 12/3 hot wires to the housing.
There will be one hot wire (red or black) to the exhaust fan hot, and then light hot to the second 12/3 hot (red or black).
The light and exhaust fan hot wires from the housing may be red, black, or blue. You will need to connect these wires together using either wire nuts, quick connects, or Wago lever nut.
Step 5 – Connect the Neutrals At Housing
Connect the single neutral wire from the new 12/3 cable to the neutrals coming from the exhaust fan and the light.
These neutrals will have to all be connected together using a wire nut, quick connect, or Wago lever nut.
Step 6 – Push Wiring Into Housing And Secure Cover
Push the wire connections into the bathroom fan housing or wiring compartment.
Re-install the wiring cover plate. Make sure that the wiring is protected from sharp edges by installing a connector or grommet.
Step 7 – Route the New 12/3 Cable to the Double Switch
If the walls are finished, the new 12/3 cable needs to be fished through the ceiling to the wall switch.
If you have attic access, it can help to do it through the attic.
Routing the new 12/3 cable to the wall switch can be the most difficult part of the entire wiring job.
Read Also >> How To Replace A Bathroom Fan Without Attic Access?
Step 8 – Connect the Grounds At Switch
Connect the grounds all together at the wall switch.
There will be one ground coming from the new 12/3 cable from the bath fan; another ground will be from the wall switch box, and the third ground will be from the panel box.
These grounds will all need to be connected using a wire nut, quick connect, or Wago connector. You will also need to create a ground pigtail (short ground wire) that goes from the switch itself to this pigtail.
After connecting the grounds together, push it towards the back of the switch box to get it out of the way.
Step 9 – Connect The Two Neutrals At Switch
Connect the neutral wires to the wall switch box.
There will be one neutral coming from the bathroom fan, and there will be a second neutral coming from the panel box.
You will need to connect these two neutral wires together with a wire nut, quick connect, or Wago lever nut. After connecting them together, push it inside the switch box to get it out of the way.
Step 10 – Connect Ground Pigtail To Switch Terminal
Connect the ground wire from the pigtail (created earlier) to the switch itself.
Simply wrap the ground wire clockwise around the switch ground terminal and crimp it.
And then you can use a screwdriver to tighten the nut.
Step 11 – Connect Power to the Common Terminal
Connect the single power wire (from panel box) to the switch terminal.
The terminal should say 'common' and you will need to connect the power wire to one of these 'common' terminals. Since it is a single circuit, you can connect it to either common terminal.
Read Also >> What Are The Code Requirements For Bathroom Fan Venting?
Step 12 – Connect Hot Wires to the Switch Bronze Terminals
Connect the two hot wires from the exhaust fan and light to the bronze terminals.
These bronze terminals should say 'A1' and 'A2'.
You will need to decide if you want the top switch to power either the bath fan or the light.
Simply wrap around each hot wire on the bronze terminal in a clockwise fashion, and crimp it. And then you can tighten the bronze terminals with a screwdriver.
Step 13 – Wrap With Electrical Tape
Wrap the wall switch once or twice with electrical tape to secure the wiring.
The electrical tape should be around the terminals.
Step 14 – Secure the Double Switch and Re-install Cover Plate
Secure the switch to the switch box using the screws provided.
And then you can snap on the cover plate or it may use a single small screw.
Final Thoughts
The toughest part of bathroom fan wiring to separate switches is usually routing the new wiring cable from the housing to the wall switch.
It can be tricky, and you may need to go into the attic to get the job done.
This part can also be greatly helped if you call in a qualified electrician because they have a lot of tricks at their disposal.
And don't forget there are a lot of different types of wall switches that you can connect to a new bathroom fan and light. There are timer switches, and even switches with humidity sensors built-in.
I hope you enjoyed this guide; please leave a comment or question below.
6 thoughts on “How To Wire A Bathroom Fan And Light On Separate Switches? (14-Step Guide)”
this should be simple but im having issue with my exhaust fan i have a black,white and green from my exhaust fan,i have black,white and green coming from dining room and white,black and green from light switch ….what goes to where
Basically, the black wire from one switch (outgoing to the fan) connects to the black wire from the exhaust fan. And the other black wire from the other switch (outgoing to the light) connects to the light’s black wire. The white wire from the switch should be marked as hot (with tape or a marker) and connected as the hot wire for one of the switches (either fan or light). Please consult with an electrician if you have any doubts!
Wow, very clear, concise, and layed out perfectly! I thought this would apply to my situation, but I have a fan/light combo connected to two sconce lights that are all combined in one switch. What I want to do is separate the fan/light combo from the two sconces so that the fan/light can be connected to a timer switch. Thanks so much.
You need to run a new hot wire from the fan/light to the new timer switch. Leave the sconces connected to the existing switch. Ensure the neutral and ground wires are properly connected for both circuits, and cap any unused wires. This will allow the fan/light to be controlled by the timer while the sconces remain on the existing switch.
I just installed a broan bathroom heater,light,nightlight, and fan in. I need to know if the single black wire hanging free needs to be connected to the black wires to get the heater working.
Hey Brian,
I don’t know what bath fan you purchased. But as an example, the Panasonic WhisperWarm with light has a black wire for the fan, a red wire for the heater, a 2nd black wire for the light, and a blue wire for the night light. All of these wires will have to be connected to switches in order for the fan to work.
Cheers,
Arie