replacing an electrical box

I need some advice on replacing an electrical box. I am installing a bathroom fan and I want to wire it into the existing switch. But I figure I will have to remove the old one completly and put a new one in. Given the little working space that a switch provides how does one insert a new box without making the opening bigger. The bathroom is paneled so making the working area bigger would make it hard to cover up the opening. Any advice, tips, tricks or other ideas would be appreciated.

Thanks
Bruce55

 

Go shopping for a "old-work construction-cut in box" "wall box with ears" Your local hardware store will know were to guide you to what you need, And also give you some indication of how it installs. Explaining it really isn't a good way, then seeing what they look like, and how to install them.

 

Is it possible to gain accesss to the light j-box or wiring instead of trying to fish a wire into the switch box?That is,unless you plan to switch them separately.

Is there a neutral available at the switch box?It could just be a switch loop.

 

"Is there a neutral available at the switch box?It could just be a switch loop."

That is an important issue to resolve before you go too far. Take a look inside of the switch box and give us an inventory of the wires in there. If it is just a switch loop, you'll need to take the power from another source.

I recently completed a similar project in my home and had to replace the existing box. Based on the size and number of wires in your box, you may be able to use a combination switch, which is two switches that only take the space of one. Or if you want the fan to run whenever the lights are on you won't need another switch.

If you do decide to replace the existing box with a double gang box--space for two devices--than you will need to enlarge the wall opening a bit. In your case you'll need to be careful and accurate with your cuts. Paneling is difficult to patch if you make the hole too big.

 

If your problem is controlling a fan from an existing switch outlet box that can accept only one device and you need 2 switches at the box, you can use a single device that has 2 seperate switches on one "yoke". The "yoke" is the device bar that is fastened to the box with machine screws. This is a "Duplex" switch device. The switch outlet box MUST contain a "feed-in" cable with a Neutral conductor for this type of connection.-----Good Luck!!!!!