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I have a single gang in wall outlet in my basement. I would like to adapt it into surface mount EMT conduit to get an outlet at a different location. Ideally I would be able to keep a plug at the current location, but its not critical.

Once site I found online said to remove the old in-wall box, patch the drywall, and install a new surface mount box.

Is there a simpler way, possibly by installing a face plate or new box on top of the existing box?

JBCP
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1 Answers1

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There are collar boxes available that have conduit KO's (knockouts). Just install one on top of the existing device box and run your conduit.

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This one is even better as it has more volume:

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Brand: Steel City, Part number:531511234UB

Here is a raised device cover to be used with the 4x4 box shown. They can be had in any number of different configurations.

enter image description here

Speedy Petey
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  • The first two pictured are actually the desirable surface mount adapters if one wants to keep an outlet at the current location. The second one could support an added outlet or two if the appropriate cover plate with outlet cutouts is used. – Michael Karas Oct 12 '14 at 04:24
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    True. A 1900, or 4x4, device cover (often called an industrial plate) is an extremely common items though. The problem with handy boxes (the smaller ones above) is their tiny size. Most times they are too small to compliantly do anything. This is why a 4x4 with a device cover is preferred. – Speedy Petey Oct 12 '14 at 13:16
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    Example: http://www.garvinindustries.com/images/itemimages/G1938.jpg Edited answer also. – Speedy Petey Oct 12 '14 at 13:18
  • How can I know what volume I need in a box? – JBCP Oct 12 '14 at 18:25
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    You would need to calculate the number of conductors, times the volume rating for each, compared to the volume of the box. IMO this is not worth doing if you are going to use a larger box. The bottom line is to use a box that does not cramp all the wires you have, and the smaller "handy boxes" typically will do this. – Speedy Petey Oct 12 '14 at 19:29
  • Here is a very good tutorial on box fill from one of the best electrician's web wires around: http://ecmweb.com/code-basics/box-fill-calculations (I know it's a link, page too big to bother copy/paste) – Speedy Petey Oct 12 '14 at 19:31
  • Is it safe to add a collar box to an existing in-wall box? I assume the new box should be flush/in-contact with the existing box right? I know a common mistake is to add wood paneling or something on top of an in-wall box and then put the face plate over the paneling, which would expose the paneling to a potential fire hazard. I wouldn't want to do the same thing with one of these boxes. – JBCP Oct 13 '14 at 20:19
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    Then trimming the paneling back to around the box and using a proper box extender would be the solution to that. – Speedy Petey Oct 13 '14 at 21:05
  • Ok, thats what I thought, I just wanted to confirm that a plastic box to this type of extender was considered up to code. Thanks! – JBCP Oct 15 '14 at 02:32