I've got a surface mount box mounted to the drywall. I now want to run an outlet to the adjacent room on the other side of this wall, but not directly lined up with the existing box.

Is there any problem with knocking out the knockout pointed to by the green arrow and just drilling a hole in the drywall big enough to fit the MC connector and then running the MC to a flush mount box on the other side of the wall?

enter image description here

  • Is there a reason you want to use MC for this instead of say a rigid nipple? I take it we're talking about a standard 2x4 wall, by the way, and how deep is the new box you're adding, for that matter? – ThreePhaseEel Nov 20 '20 at 1:51
  • @ThreePhaseEel I didn't know it was possible to use real conduit in a situation like this - how would I bend it and fish it to where it needs to do? It's going to run to a little 2" deep 1-gang box. – David Doria Nov 20 '20 at 2:04
  • Is the new box not directly across the wall from the old box? – ThreePhaseEel Nov 20 '20 at 2:24
  • @ThreePhaseEel No, sorry. The original post was edited - I just edited it again to clarify. – David Doria Nov 20 '20 at 2:27

It appears that there's a screw just to the left of your green arrow that holds the box to the wall. If that screw is centered on the stud, then it's likely that the stud will actually be blocking both knockouts to the left and right side. i.e., you could get the knockout out, but there may not be enough room for the connector or conduit.

If that's the case, you'd want to go with a knockout on the right side of the box, directly into an elbow pointed at the wall. Run your conduit through the wall at that point, then decide if it's going to go into the back of a box on the other side or into the side like this one.

Other than that (and ensuring you don't exceed fill limits), there should be no problem with your desired method.

  • thanks! The box is actually screwed to the wall using drywall anchors, so there is no stud blocking the knockout. I'm planning to just drill delicately as to hopefully not disturb the anchor :). But it's good to know the alternative is to use a 90 degree elbow from the side of the box directly into the wall. – David Doria Nov 19 '20 at 17:28
  • @DavidDoria please note that I'm not a licensed electrician and don't know code inside and out. Make sure someone else confirms this. However, nothing I've read here from the electricians says that you can't do something like this. – FreeMan Nov 19 '20 at 18:05
  • 1
    Also, there should be other small holes in that box that you can use to re-anchor the box to the drywall if necessary. – FreeMan Nov 19 '20 at 18:06

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.