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View Full Version : Receptical boxes and drywall depth issues


justincaseme
May 2, 2008, 11:15 PM
Hello -
I have a room torn down to the studs where I've run all new electrical wiring. Now I'm in the process of putting up new 1/2" soundboard in some places and 5/8" drywall everywhere (so, 8/9" total thickness in some locations). The books on electrical wiring that I read didnt address the issue of box depth and drywall thickness very clearly though :confused: ...

* I have a metal ceiling fan box that I attached to a joist using the guides on the box. After installing the drywall on the ceiling (no soundboard on the ceiling) the bottom lip of the box was recessed below the drywall surface about 1/4". Is this going to be a problem when I mount the fan? Do I need to adjust the box depth? (very difficult to access the location where this box was installed)

* For the wall outlets (almost all duplex) I initially used the cheap self-nailing kind for the walls that didn't include soundboard. I followed the guides on the boxes exactly, but they always result in the boxes being recessed well below the surface of 5/8" drywall. Is that normal? In the locations with soundboard I used the duplex boxes that allow you to adjust depth by turning a screw - these are great, but they are about $4 more than the regular boxes.

* In my electrical books, the pictures of rough construction (no drywall) always show the receptacles fully installed prior to the drywall going up. Is that really how it's done? How can you cleanly cut out the drywall hole without damaging the receptacle? It makes more sense to me to remove the receptacles first. How do the pros do it though? Any tips would be much appreciated!

Thanks!!
Justin

Clough
May 2, 2008, 11:46 PM
Hi, Justin!

I just wanted to say that, around where you live, there may be current books on the Electrical Code for your area. There is such a book available around where I live. It can be purchased at most hardware and home-building type stores. Perhaps some of the questions that you have might be answered in a book such as that?

Just a thought for you...

I'm sure that others with a lot of experience in such things will eventually be along to advise you.

ceilingfanrepair
May 5, 2008, 03:23 PM
I can't speak for the legality of it, but a box not being properly flush rarely affects the installation of a ceiling fan. At worst, there might be a 1/4" gab between the fan canopy and the ceiling. The manufactures used to recommend this.

donf
May 6, 2008, 07:10 AM
WRT the wall switches and receptacles,

The fireproof rating of the wall directly affects the mounting of gang boxes.

If you need me to dig up the codes, I'll be happy to. On normal gypsum walls, the boxes are flush with the surface of the drywalls outer surface. On fireproof walls, I believe that you should mount the boxes 1/4 inch below the surface of the outside wall surface.

I do need to check the code for the ceiling, but I believe that the same is true.

Be back to you in a few moments.

donf
May 6, 2008, 08:25 AM
Justincase,

FWIW - I have a nephew, whose mother was so sure she was going to have a girl that she never picked a boy's name. However, toward the end of her pregnancy, they decide that, "Just in case" the child was a boy they had better be prepared. They could not come up with one so when the boy appeared on the scene, "Justin Case" became his name.

Any way, the NEC Code cite is 314.20:

In Wall or Ceiling. In walls or ceilings with a surface of concrete, tile, gypsum, plaster, or other noncombustible material, boxes employing a flush-type cover or faceplate shall be installed so that the front edge of the box, plaster ring, extension ring, or listed extender will not be set back of the finished surface more than 6 mm.


In walls and ceilings constructed of wood or other combustible surface material, boxes, plaster rings, extension rings, or listed extenders shall be flush with the finished surface or project therefrom.

justincaseme
May 25, 2008, 04:48 PM
Justincase,

FWIW - I have a nephew, whose mother was so sure she was going to have a girl that she never picked a boy's name. However, toward the end of her pregnancy, they decide that, "Just in case" the child was a boy they had better be prepared. They could not come up with one so when the boy appeared on the scene, "Justin Case" became his name.

Any way, the NEC Code cite is 314.20:

In Wall or Ceiling. In walls or ceilings with a surface of concrete, tile, gypsum, plaster, or other noncombustible material, boxes employing a flush-type cover or faceplate shall be installed so that the front edge of the box, plaster ring, extension ring, or listed extender will not be set back of the finished surface more than 6 mm.


In walls and ceilings constructed of wood or other combustible surface material, boxes, plaster rings, extension rings, or listed extenders shall be flush with the finished surface or project therefrom.




Thanks Don, I appreciate the info. I've been too busy at work the last couple of weeks to work on my remodeling project, but I was very interested in the answer to this question. It looks like I may have to adjust my ceiling fan mount. Sad part is, I already installed the insulation and some plywood flooring on the attic side, so it's going to be a to access.

Interesting story about your nephew. It's said that names influence a person's perception of themselves and even their values and personality. If that's true, your nephew is destined to always be prepared in true boyscout fashion.