Putting drywall on studs, I can add switches and outlets using New Work boxes that stick out from the studs or I can use a plain junction box and add mud rings. Are there any pros or cons?

For me, the biggest difference would be that with New Work boxes I'd have to develop the skill to accurately cut drywall to fit. I know of several techniques but they all require practice and experience. Cutting it after installation from inside a plain junction box seems easier.

  • I believe that even with a new work box, you can just tack the drywall in place with a couple of screws, then run your RotoZip™-type router around the outside of the box to "pop" the box through the drywall then finish screwing down the drywall. At least, that's the theory...
    – FreeMan
    May 5, 2022 at 21:53
  • Yes, that is one of three ways that are all quite simple in theory but require some practice. As Harper pointed out, I was wrong to think I could install a mud ring after drywall. I realize now that doesn't make sense. So I'll have to learn one of these skills the hard way. IE 1) meticulous measurement 2) route it out as you say, 3) Chalk the front of the box to template the back of the board. I've tried and failed (once) at all of them and exhausted my supply of drywall offcuts. :(........
    – jay613
    May 5, 2022 at 22:05
  • 1
    I've been reasonably successful at the "meticulous measurement" method. Except when I've measured from the back of the drywall and marked on the front, or vice versa... Wife just got me a cordless drywall router, so I'll have to give that a go when we finally get this bathroom addition project underway.
    – FreeMan
    May 5, 2022 at 22:07
  • I bought drywall bits and used my drill instead of my rotary tool. Maybe the relatively low speed of the drill was the problem but it wandered like crazy. I'm not going to buy a dedicated tool for this task. If I can't get it right one of the other ways I'll resort to old work boxes.
    – jay613
    May 5, 2022 at 22:11

2 Answers 2


You must install the mud ring before fitting drywall, so it doesn't buy you any advantage there.

The biggest advantage of mud rings is they are typically used with 4x4x1-1/2" steel boxes, and that means, you have a very shallow box. 2 such boxes can exist back-to-back in a 2x4 stud wall (and with a conduit nipple pass-thru between them) which means

  1. the boxes are more sturdy with the pass-thru giving strength.
  2. switches can be back-to-back with no need to offset them.
  3. it plays well with my preferred wiring for receptacles, which is to run 1 cable down the wall and feed rooms on both sides. 1 circuit per wall (coarsely) and now each room has access to 3-4 circuits (shared). So the "home office" room isn't starving for power.

Having installed a few of each now I'm going to answer with a huge vote for mud rings because:

  1. You can use a box one gang larger than you need and a reducing mud ring, which provides lots of space to work and moves the devices away from the cable entries and the box's ground screw. (You can do the same with an oversized new work box by adding a blank position intentionally).
  2. You can adjust the mud ring slightly -- up, down, left, right and rotated in the wall's plane so you don't have to worry as much about the box being perfectly aligned when installing it.
  3. It's much easier to mud a tight seal between the box and the wall void with a mud ring, which helps with reducing noise and dirt in the finished product. And your drywall cutout doesn't have to be quite as perfect.
  4. The mud ring provides a strong backing for tile, especially small or mosaic tile, right up to the edge of the opening so it's easier to install the tile and easier to install the switches and outlets without breaking the tile.
  • Nice! I'll be doing an addition to the house soon and will definitely keep this in mind!
    – FreeMan
    Jun 2, 2022 at 13:34
  • 1
    @freeman I just added reason #4 to the answer, and now, with hindsight and a bit more experience, I highly recommend that for ceramic tile you do a small mock-up with your chosen tile and thinset, and find the appropriate mud ring that gives you a perfect result. With a "new work" box, the tiles immediately adjacent get crushed/broken by the device plaster ears. With a mud ring, the metal backing provides a solid surface for everything.
    – jay613
    Jun 16, 2022 at 20:15

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

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