Shallow Wall Cavity for Junction Boxes, Cut Back of Boxes or Surface Mount?

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Molo

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Hello,
I need to install a few junction boxes in an old home. I've tried to use the standard old-work boxes, but they are too deep.

I've considered cutting the back of the box, but not sure if this is acceptable. I'm also wondering if there is a decorative surface mount box available?

Thanks in Advance!
 

Jadnashua

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No, the whole idea of the box is that it is enclosed when the cover is on...cutting the back off defeats that purpose. I've seen (and used) some shallow boxes. Keep in mind they limit considerably what you can put in them both in devices and cables.
 

Molo

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I was considering modifying a box by drilling two holes in the bottom for romex connectors. This would allow me to bring the wires into the box from a location other than the back of the box. I could then make a new back for the box that could be held on by a couple of small bolts and washers.
I can't seem to find a shallow box elsewhere so am considering options.
 

Molo

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The problem is depth of the conventional boxes. When they go into the wall they hit studs, or sheathing. I only want to join two pieces of 12-2 together so don't need much space.

This does raise the question about the amount of open space in the plastic boxes around where the wires enter the box. The plastic tabs leave quite a bit of open space once the wire is pushed into the box, which makes me wonder what the problem is with not having a back on the box?
 

ActionDave

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How deep is the cavity? A shallow 1900 box, also called a four square, is only 1 1/8" deep. You could also surface mount it, or come in the back of a wire mold box.
 

Speedy Petey

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The problem is depth of the conventional boxes.
There is no "conventional" box. Cut-in boxes come in all differeent depths.



This does raise the question about the amount of open space in the plastic boxes around where the wires enter the box. The plastic tabs leave quite a bit of open space once the wire is pushed into the box, which makes me wonder what the problem is with not having a back on the box?
PLEASE stop wondering this. You are questioning 125 years of code changes. The box needs to be in tact for a reason!



I was considering modifying a box by drilling two holes in the bottom for romex connectors. This would allow me to bring the wires into the box from a location other than the back of the box.
WHY are you coming into the back of the box? NM cables enter the bottom of every plastic cut-in I have ever used.


May I ask why you have to splice these cables in a finished wall???
 
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I only want to join two pieces of 12-2 together so don't need much space.

You do not need boxes to splice NM.

There are recently approved spice devices that cost about $6. They have a pretty solid grip on the cable such that the join is not going to be pulled apart, which is the key reason that just wire nutting in a wall cavity is illegal.

And just how deep is the wall void that you are working with?
 

Big2bird

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You do not need boxes to splice NM.

There are recently approved spice devices that cost about $6. They have a pretty solid grip on the cable such that the join is not going to be pulled apart, which is the key reason that just wire nutting in a wall cavity is illegal.
Do you have a link for this item?
 

hj

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quote; remember that it has to be accessible

ANd the easiest way to make it "accessible" is to make the connection in a box. So he is back to his original question, and the answer is a shallow box, but since an "old work box" with toggles does not come in a shallow pattern, he needs the sheet metal "T" grips that fit into the opening on either side of the box, then bend around the side edges to hold it in place.
 

Molo

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The local hardware has a plastic box that is only 1" deep. It has a knockout on the top and bottom. It doesn't have the screw-tightened tabs that the "old-work" boxes do.
 

Jim Port

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You may not think you need that much room but the required space is specified by the electrical code. For 2 12-2 cables without a device you need at least 5*2.25 cubic inches. with a device you need at least 7*2.25.
 

Cacher_Chick

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I'd be curious to see what you are working on, as all the old houses around here used "real" 2"x4" studs with lath and plaster walls. There is just as much space inside those walls as are found in most new construction today. Maybe it's just a matter of putting the box somewhere other than the exact location that you have looked at.
 

JWelectric

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"Accessible"?

What is the point of that? I had understood that it could be closed in a wall.

Not that I was not surprised to learn that one could close it up.

Only in mobile homes and RVs can they be conceled.

300.15(F) Fitting. A fitting identified for the use shall be permitted in lieu of a box or conduit body where conductors are not spliced or terminated within the fitting. The fitting shall be accessible after installation.

550.15(I) Boxes, Fittings, and Cabinets. Boxes, fittings, and cabinets shall be securely fastened in place and shall be supported from a structural member of the home, either directly or by using a substantial brace.

Exception: Snap-in-type boxes. Boxes provided with special wall or ceiling brackets and wiring devices with integral enclosures that securely fasten to walls or ceilings and are identified for the use shall be permitted without support from a structural member or brace. The testing and approval shall include the wall and ceiling construction systems for which the boxes and devices are intended to be used.
 

hj

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quote; as all the old houses around here used "real" 2"x4" studs with lath and plaster walls.

I worked in a Frank Lloyd Wright house which had 2" and 3" walls, He did not believe in wasting space for walls when it could be used for live in purposes.
 

Bsperr

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What's inside the wall that is preventing the box from sitting flush and how proud does it sit from the wall? A picture of two would be very helpful. If the box is being obstructed by something inessential, like blocking or nailers on an interior wall, I would take a spade bit and drill out some of that material through the cutout for the box until it sits flush. Obviously, you wouldn't be able to do the same thing if the box was butting up against the exterior sheathing.
 

Molo

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What's inside the wall that is preventing the box from sitting flush and how proud does it sit from the wall? A picture of two would be very helpful. If the box is being obstructed by something inessential, like blocking or nailers on an interior wall, I would take a spade bit and drill out some of that material through the cutout for the box until it sits flush. Obviously, you wouldn't be able to do the same thing if the box was butting up against the exterior sheathing.

Thanks for your response, I was able to find some shallow plastic boxes (1" deep) They have tabs that go over the face of the wall surface, and say that the cable must be attached within 12" of the box.

Also,It's interesting that those splices can be made in RV's and trailers and not homes. Why is this?
 
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