Return to the Electrical Wiring Forum | Post a Follow-Up

Metal 2 gang box to plastic 3 gang??

Posted by angalalu (My Page) on
Sun, Nov 25, 12 at 21:24

My house was built in 1926, hence, the switch boxes are all metal with conduit. There is an existing box, which houses a double switch and a single pole switch that operates 2 sconce light fixtures. My hope was to convert this metal beast to a 3 gang box and add a three way switch and another sconce light fixture, making the existing single pole double switch into a dimmer three way switch. does this make sense? anywho, I opened up the box and I am unsure where to start. I have some elementary wiring knowledge and many books, but none explain how to deal with expanding and existing metal box. I am thinking that because of the attached conduit, unless I intend to replace that with romex, it should be left in place. Is it ok to add an 'old work' single gang, plastic box next to the metal box? If so how would I knockout and mosy the wires over to the new plastic box? Someone with more knowledge, please advice. Even if its to say don't be a fool and pay an electrician a few hundred bucks. Thanks!

Follow-Up Postings:

RE: Metal 2 gang box to plastic 3 gang??

What is the wall construction? Plaster over wood lath? How much patching would you be willing to do?

RE: Metal 2 gang box to plastic 3 gang??

The first question is where are you located and are plastic boxes and Romex allowed. That's actually two questions.

RE: Metal 2 gang box to plastic 3 gang??

bus driver: yes, indeed, it's plaster over wood lath. we just paid to have the wall with metal box in question smooth coated... so, as minimal as possible so I don't have to kick myself in the butt. However, adding the three way switch and new light fixture will improve lighting and functionality of the house, so I will consider :)

hendricus: yes, plastic boxes and Romex are allowed. I'm in Southern California.

RE: Metal 2 gang box to plastic 3 gang??

In some instances such as yours, where the wall was an exterior wall and the outside finish permitted it, the outside clapboards were removed to access the wall cavity from the outside.

RE: Metal 2 gang box to plastic 3 gang??

You can also check into different switches (not regular toggle switches) that might not require any box change.

 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!

Return to the Electrical Wiring Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Please review our Rules of Play before posting.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.

Learn more about in-text links on this page here