A junction box is a container used to enclose electrical connections (junctions).

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What's the minimum depth that an electrical box can recess into a finished wall? Does it have to be flush?

Do electrical boxes have to be flush to the finished surface? Can they recess any depth into the wall by as much as 1/8" or 1/4"? Edit: I appreciate everyone offering alternative solutions to ...
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3answers
592 views

How should I rewire this situation?

In my dinning room, I have this: There is a wire run going up through the floor from the basement. It then goes outside the wall, around a stud (or studs, I'm can't tell there is more than one), back ...
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3answers
4k views

How can I install a ceiling fan that needs a 4“ box where I only have a 3” box?

As part of a home renovation project I discarded my old ceiling fan and have bought a new one. When installing the new one the electrician tells me that I have a 3" junction box and that I'll need a ...
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3answers
7k views

I modified a nail-in electrical box to use screws instead of nails. Is there some code that prevents that?

Ever since I dove into the electrical side of things with my project, I've encountered a bunch of code restrictions. One thing that wouldn't surprise me if it was a violation of code is what I've ...
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1answer
6k views

How to open NM box knockouts?

I've found the knockouts in NM boxes hard to fully open. I've had trouble with both Carlon boxes and Madison Smart Boxes. The plastic molded to make the knockout is very resistant to actually being ...
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3answers
160 views

Is this Junction Box too full?

I'm installing a flood lamp on my outdoor garage. So, I went to take look at the junction box, and to my surprise, it appears oddly filled: Filled to the point where I almost feel as though it's ...
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2answers
11k views

Can I screw a ceiling fan electrical box directly to the joist?

I am putting in a ceiling fan in a bedroom. It is a smaller one approx. 18 lbs. The remodeling-type expander brace failed, so can I just screw one side of the box to the joist? (I cannot access the ...
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2answers
17k views

Is there any acceptable way to cover a junction box?

The outlet for my range hood was misplaced. It needs to be 4 inches to the side. I can make the junction and move the wiring to the new location but I really don't want to have the empty plate ...
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5answers
15k views

Is this an adequate junction box wire job using a standard electric box? (pic included)

I needed to splice a wire to repair nicked wire insulation, but I didn't feel like running to Lowe's just for a junction box. Instead, I used a regular electrical box. The wire comes up from the ...
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2answers
3k views

Do metal junction boxes used solely as pull boxes need to be grounded?

I am planning to pull three sets of four conductors (3 AWG wire) through 2" EMT conduit for a 30' length that is common to all three sets of wires, and then branch off at a listed metal junction box ...
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5answers
24k views

Can I cover junction boxes in the attic with insulation?

This may be a duplicate of What are the codes for electrical wiring in attics? I have an attic which is accessible via a ladder through an access panel in the garage and in a bedroom. The trusses ...
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2answers
814 views

Can an open junction box be allowed over an enclosed ceiling?

I am renovating my basement and there is currently a suspended ceiling. After removing some of the tiles I noticed there are some junction boxes without covers. I want to replace the suspended ceiling ...
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4answers
5k views

How do I install a junction box with NM-clamps?

I bought a junction box in order to splice three Romex together along the 2x4's in the ceiling of my (unfinished) basement. The box looks like this: When I bought it, I assumed that I could just ...
4
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2answers
8k views

How can high and low voltage be mixed in a junction box?

So I'm aware of the standard rule of thumb, keep high and low voltage away from each other, preferably on opposite sides of a stud. However, while looking at some properties, I'm seeing telephone and ...
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1answer
18k views

How to tell if a ceiling junction box is braced to hold the weight of a ceiling fan?

My new home is almost done being built, and one of the extras I asked for was for two of the rooms to have junction boxes in the ceiling suitable for hanging a ceiling fan in the future. The light ...
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1answer
257 views

Are these black marks near an electrical box signs of an electrical problem that I should be concerned about?

My garage has an electrical box with no receptacle in it, just wire-nutted wires. It came this way when I bought the house. A non-contact voltage tester shows that the black wires are hot. I was ...
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2answers
881 views

What are these “GENTEX” things on my walls?

My condo has these devices installed in each bedroom and in the living room; but I have no idea what they're for.
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2answers
907 views

Why are the neutral wires not connected in this box?

I want to connect the wiring from my shed into a junction box on the ceiling in the basement. I opened the box to see what I was dealing with, I figured it should be simple, there is only 2 wires ...
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1answer
89 views

Round hole, rectangular junction box

I am installing a new light fixture into ceiling. There is a round hole there right now (from a recessed light that I removed). The problem is this round hole is just short in diameter of standard ...
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1answer
90 views

What exactly does 'Maximum of 8 No. 12 AWG Branch Circuit Conductors' mean?

I'm installing some recessed lighting, the lights are IC and wet location rated if that helps. The plates on the junction boxes attached to the cans say' Mamixum of 8 No. 12 AWG branch circuit ...
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2answers
483 views

How can I mount an electrical box to exterior foam board?

I am trying to replace an exterior light fixture next to my home's main entry way: The original light was mounted to a low-profile bracket that was mounted directly to the PVC "box" shown in the ...
3
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1answer
346 views

At what voltage are “low voltage” junction boxes not appropriate?

120VAC needs a proper, enclosed junction box. Speaker cable, data, and low voltage power are fine with the more open low-voltage boxes. At what voltage are the enclosed boxes required? Do PoE lines ...
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2answers
7k views

What is the proper way to leave unused nonmetallic sheathed cable inside walls or ceilings?

The question pretty much sums it up. I nailed through a live wire in my ceiling. Rather than splice it and install a jbox, I ran a new run to the outlet. However, I took a slightly different route ...
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3answers
15k views

Is it possible to install a ceiling fan without an electrical box?

A while ago I had some electricians install a ceiling fan mount. Now that I've finally gotten around to installing a fan I've discovered that they didn't install any sort of electrical box to house ...
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3answers
694 views

Ceiling Fan Junction Box Converter/Bracket 1/2 inch width difference

First time poster. I feel like I have researched everywhere and not found the answer I am looking for. I've called a few manufactures of ceiling fans who didn't have any answers either. I began ...
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3answers
24k views

What is the proper way to install a junction box above a dropped ceiling?

I'm doing some remodeling in my basement and part of that work involves moving a switch. When I was tracing the wires for the switch I found this above my dropped ceiling: Now, I'm no electrician, ...
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1answer
2k views

Is it against code to create a romex to thhn junction inside a conduit body?

I'm installing a 60A subpanel in my detached garage. I'll be running 2GA conductors, to leave the possibility of upgrading to 100A service in the future open. The Breaker I'll be using on the main ...
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2answers
153 views

Connecting Three 12 Gauge Wires

When I purchased our house the previous owners recently installed electric baseboard heaters in rooms A, B and C. I did not want to keep these but needed more outlets so I had swapped the breaker at ...
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2answers
423 views

How should I connect a grounding wire from a device to this box?

I'm replacing this simple 2-connector light switch with a 4-wire dimmer. The 2 new wires present on the dimmer are neutral and ground, and only neutral has an obvious home. The box has no visible ...
2
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1answer
258 views

What is this electrical junction box? (re: adding 3-way switch)

I'm trying to replace an existing switch (at the top of the basement stairs) with a 3-way switch by adding an additional switch at the bottom of the basement stairs. The existing switch box has 4 ...
2
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1answer
251 views

What can I do if I need another gang in a junction box but there isn't space in the wall?

I have a dual gang junction box installed in a space between 2 studs in the wall. I want to add swap the box for a 3-gang box to add another switch for a ceiling fan, however when I took the cover ...
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1answer
2k views

Can I install junction boxes in a closet, and if so, what kind of box?

We are designing circuit runs for a ground floor of a house flooded by a hurricane and it is best to use a few junction boxes to run the circuit branches. One reason for the junction boxes is to keep ...
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2answers
46 views

3-inch recessed lighting junction access

I am looking to install 3-inch recessed lighting in room under living areas. I have the ceiling down so I am using a new-work kit with rails and a pan. The lights are sold as remodeling and the rest ...
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2answers
262 views

Is there a way to extend electrical wire where the splices can be finished over? [duplicate]

I want to extend some wires to relocate some switches. Normally one might do this by splicing new wires in and covering the junction box with a cover plate. Is there a way to permanently splice wires ...
2
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1answer
307 views

How do I seal an electrical box for a ceiling fan?

We recently installed new electrical boxes and hung fans from them. We caulked around the boxes to seal off airflow into the attic. There are several small holes (and one has a medium sized hole) on ...
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2answers
264 views

Is it possible to convert an octagonal electrical box so that it can house 2 Duplex outlets without changing the shape of the box?

I currently have 1 Duplex outlet installed in an octagonal box mounted on the ceiling. I need to add another outlet to make it a 2 gang. However, I can't find a cover that will hold a 2 gang outlet ...
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2answers
734 views

Replacing an outdoor junction box - need some help

Last year we had a contractor come to our house to do a few jobs. In the process, he ended up saying he busted a light bulb on our security light, and said he would fix it. About a week later, we ...
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1answer
400 views

Ground wire is hot, drop ceiling carrying current?

I am no electrician by any means but I have ran thousands of feet of wire, hooked up receptacles, lights, hot water heaters, breakers, etc... the average things with never an issue. I ran some new ...
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1answer
43 views

Is there any easy way to mount multiple single gang low voltage panels in a multi-gang box?

So, a combination of AT&T, Comcast, and the previous owner of my house and made an absolute mess out of the area I'm wanting to use as the network hub of my house. There are five outlets, one for ...
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2answers
2k views

How does one typically do “Old Work” with metal junction boxes?

I am trying to add a light fixture to a room. I have access to the studs in the wall (new wall being added to the room), but the ceiling is drywalled. There is no attic access. Unfortunately, the ...
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1answer
130 views

Wiring a Junction Box: 1 source in, 2 sources out

I have an existing junction box and currently 1 source from the basement going in, and one source coming out and that goes to a wall switch. If I want to connect a second wire to come from that ...
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2answers
2k views

Do I need a junction box for a hardwired stove?

I'm replacing my drop-in electric stove with a free-standing electric stove (both are rangetop + oven). The drop-in stove was hardwired and the wiring comes up out of a hole in the floor about 3" from ...
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3answers
108 views

How to properly bond metal junction box with 6 AWG conductors

What is the appropriate way to bond a metal junction box containing a receptacle wired with 6 AWG wire? It seems that most metal junction boxes have a 10-32 tapped hole to accept a ground screw but ...
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1answer
908 views

Can I put the junction box for an exterior wall fixture inside my garage?

I have an exterior, wall-mounted light fixture that I want to attach to my new garage. It looks like this: Here's a PVC board the contractor left to mount it. There appears to be OSB sheathing ...
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1answer
205 views

Which wires do I connect to my new ceiling fan?

I looked all over the internet and my outlet box seems to have unorthodox wiring/ colors. On the ceiling outlet box I have 3 thick wires, red, white and green, and a fourth single little wire that ...
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3answers
362 views

How can I secure wire fished between two plastic switch boxes?

I have two light switches in two separate plastic switch boxes. The upper box controls the motor of a fan, and the bottom switch controls some outlets. I want to change the wiring so that the bottom ...
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1answer
45 views

What fastener to use to attach 4" circular pan to steel stud?

I need to attach a 4" circular pan circuit box to a steel stud in order to hang a bathroom vanity light fixture. The fixture weights less than 10 lbs, but assume some future homeowner will want to ...
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4answers
391 views

Can an electrical junction box be closed and covered if not needed?

Can an octagon fixture box that was also found to be a junction box, be closed and covered over in the ceiling after remodeling. Box not needed.
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2answers
929 views

Doorbell for a rectangular switch box [closed]

I have a doorbell button that goes on a rectangular switch box that is outside my house. The rectangular switch box is inside concrete. Since the doorbell button is outside exposed to the weather, the ...
0
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1answer
71 views

Does this j-box follow NEC electrical code?

I'm considering buying the following product for a security floodlight install: Arlington 8141-1 Vertical Siding Lamp Mounting Kit with Built-in Box for 1/2 Inch Vertical Siding LAP. It seems to get ...