Electric outlet on the mantle?

[Corey]

Well, just taking a break from splitting up the latest load of solid gold...ur...uh, I mean hedge. The stove room has been reduced to rubble in anticipation of the upcoming remodel and I've been kicking around a thought or two. One of which is installing an electric outlet in the mantle.

It seems like we're always wanting to plug something in up there, whether it is a fan, Christmas lights, Halloween decorations, general ambiance lighting, etc. This usually means an extension cord draped across the wall from the nearest outlet. So I'm thinking why not run electricity up there and put a proper outlet right in the mantle.

My basic thought is to go through the existing wall up to the height of the mantle with normal romex, chisel a slight channel in the existing brick/mortar to hold 3/4" steel conduit which will run horizontally to an outlet box in the center of the existing mantle. The existing brick is then going to get a skin of dry stacked Montana field stone which can be relieved slightly to allow for the conduit and the mantle is going to get a skin of oak which would trim out the electric box nicely.

In short, I have a pretty good idea on how to do it, just curious if anyone had any other input or maybe someone has an outlet actually "in" the mantle and can offer suggestions / thoughts, etc.

I'm not sure exactly what building code would say (though they want you to put an outlet every couple of feet in the kitchen, so maybe the mantle is the same way?!?) But any wiring would be at least as high as the mantle and it would be in steel conduit under a stone face, so I can't see there would be any issues. I would transfer the romex into the steel conduit with the proper connectors so there wouldn't be any hidden junctions.

 

[rowerwet]

due to heat issues I don't think I would want an outlet on or in the mantle. I like what my parents have in their beach cottage, flanking the mirror over the fireplace are two light fixtures with plugs in them. That way you can plug in Christmas lights or cell phones (during the summer), and the outlets are mostly hidden by the lights when not in use. This also works great as the lights are above the mantle so you don't have a cord running up from the floor.

 

[2.beans]

i installed an outlet in the mantel and then hung a flat screen over it. i ran the wire in conduit before it was rock faced. i dont believe there would be any code issues as long as the wire was in conduit.

 

[fossil]

You indicated that your mantle incorporates combustibles ("skin of oak"). I have to assume, then, that you've met the required clearance to combustibles from the appliance to the mantle. That being the case, I can't see any problem with your plan for bringing power over there, but I'm by no means an authority. Rick

 

[Corey]

Yep, right now the mantle is a solid block of cedar ~ 5"x14" - it actually seems to be built into the brick, so I thought the easiest thing to do would be to skin over it with some solid oak. At first I thought about the heat issue, but all the electric bits would be run on top of the existing mantle, so I surely hope heat wouldn't be an issue - if that cedar hasn't lit off by now, I can't imagine anything ever would!

Usually under full fire ~900F on the center of the firebox, the steel and brick on the top of the fireplace opening a few inches above the insert will only hit ~130F because the double wall construction of the insert plus the amount of air I circulate. Of course if the power ever went out, that would probably change pretty rapidly and I suppose it is always the worst case which needs to be planned for.

 

[Gooserider]

Sounds like it would work, and probably would be OK, however it is probably something you should verify as OK w/ your local AHJ... For whatever it's worth, we have a duplex outlet in the floor of the space where our 1st floor woodstove sits, it is almost directly under the back edge of the stove. Our code guy didn't see a problem with it. (I'm not sure how the wire going to it is done, as there isn't a way to see how the box is fed w/o doing demo work, and it was put in by the previous owner)

Gooserider

 

[dgold]

I don't think you can run the romex through conduit. I'm pretty sure you're only supposed to run insulated wires through romex (ie. no jacket). I think you'll also need to have a junction box where you transition from jacketed to conduit. I'd want to find out what the NEC specifies and do that... or at the very least have a licensed electrician come out to inspect your work. Here's the worst case scenario that I always think about... God forbid I have a fire, I wouldn't want the insurance adjuster to say "Sorry, but it wasn't installed to code - go after your electrician."

ps. I'm not an electrician, but when I pretend I am, I try to understand the code and follow it as conservatively as possible.

 

[Gooserider]

As I understand it, you are correct Dave, it is not OK to run Romex through conduit. However, it is OK to run the Romex wires with the jacket removed through conduit if you are terminating on the other end, and the conduit is a short length. This saves the need for a junction box at the start of the conduit run. Obviously if the run is very long, it's a PITA to strip the jacket for very far, plus it gets more expensive...

In a case like this, where there is the potential for higher than normal temps at the outlet, I would be tempted to put the extra J-box at the start of the run anyway in order to transition to the highest temp rated THN or THNN wire I could get my hands on (I forget the exact wire designation offhand...)

Gooserider

 

[dgold]

How do you get the wires into and out of the conduit while protecting them? The sheathing is supposed to protect the wires, but the sheathing can't enter the conduit. How would you do this without a JB at each end? Also, I assume you're using metal conduit? Doesn't the conduit have to be grounded? How will you ground the conduit w/o a junction box at the start?

 

[Gooserider]

How do you get the wires into and out of the conduit while protecting them? The sheathing is supposed to protect the wires, but the sheathing can't enter the conduit. How would you do this without a JB at each end?

Careful routing, essentially making sure that the wires are entering the conduit in a "straight shot" not making a bend as they head in. Also the sheath can start into the conduit a short distance, just like you can have a short bit of sheath inside a JB... In one case I where I did this, the conduit was going through a wooden beam - the conduit ended just short of the beam surface, so the wooden beam surface also gave some protection. Of course I also was careful to thoroughly deburr the conduit end...

Also, I assume you're using metal conduit? Doesn't the conduit have to be grounded? How will you ground the conduit w/o a junction box at the start?

The conduit is grounded two ways, one reliable, the other not. First off, since the ground wire in the unsheathed Romex is not insulated, it is almost certainly going to be making contact with the inside of the conduit over a good bit of it's length. Secondly, the Romex ground wire is still going to be connected to the JB on the far end of the conduit.

Gooserider

 

[fbelec]

you might not want to install metal pipe. it will corrode in the cement very quickly. you should use pvc pipe. if you are going thru the brick cement or any type of masonry it's not code to use just romex. but you are allowed to use pvc pipe for protection. yes you can run romex in the pvc. your outlet above the mantle is ok code wise.

if possible run pvc pipe from outlet box to the basement just below the fireplace. if you have no basement, run pvc pipe to the nearest outlet box beside it and change that box to a bigger cubic inch box (per code) if the box that is there is not a 18 cubic inch box. the box can be metal and you can terminate the pipe into one of the knock out holes. if it is a plastic box run a romex out of the box and into the pipe using pipe as protection for wires. this is ok with code. and any inspector that i ran into.

or if you have no basement pun the pvc pipe from the outlet box to the attic and into a junction box up there then change over to romex or if it is a box in the attic, cheaper to run thhn type wires into the pipe and make sure you run a green in there for ground. not as hard as it sounds. and if you have to slightly bend the pvc pipe to fit somewhere get a heat gun block the two end of the pvc pipe heat the area with the heat gun and offset it that way. i don't think you want to buy a heat blanket for using just one since they cost around 160.00 just be careful not to make the pipe turn brown. heat as hot as you can get it without burning the pipe and it turns into jello.