My brother wants to add a receptacle to his bathroom. He planned to put it next to his light/fan switch. I’m fine doing the wiring, but the question i have is about going from a single gang box (switches only) to the double gang box (switches and new receptacle). Is there any sort of snap-on plastic box that is easy to add after cutting the wallboard, or would we have to use a metal box and screw it to the stud?
I haven’t actually looked it yet, but i am assuming right now he just has the typical blue plastic that is nailed to the stud, how do i get that box out anyway?
Yep. Go to virtually any hardware, home improvement or electrical supply store and ask for an appropriately-sized “old work box.” These are specifically designed to be easy to add to an existing wall without ripping out drywall. Just cut the opening to size, fit the box and tighten the fasteners.
To get the old box out, assuming it’s the universal nailed-on style, take a hacksaw blade and wrap one-third or so of the blade’s “handle” end with tape so you can hold onto it. Wiggle the blade in between the box and stud and start sawing - there’s normally only two nails holding it to the stud.
Then, it’s just a matter of getting the romex loose from the old box, keeping track of which is which, enlarging the wall opening, inserting the romex into the new box and mounting it, then putting in the switches and a GFCI receptacle.
Hold the phone… before you start sawing away at anything, ensure that you actually have a power supply to this box. If there’s just a switch loop, (The switch is connected to the black and white wires of a single romex) you won’t be able to install a receptacle unless you find a power source and get it to the box.
What they said. Confirm you have power to the existing box.
Remove the existing box while saving the existing wires. This can be very easy of a real pain in the ass. Sometimes those new work boxes are stubborn.
Use a two gang old work box cut the hole to size rewire as necessary.
The project will get you an outlet. Which is all most people want It will probably not get you the outlet required by code. Code requires a single 20 amp circuit for the sole purpose of supplying power to bathroom receptacles. As the circuit you have powers a light and is probably only 15 amp it doesn’t cut it.