Help with adding outlet for TV

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hardsoftrock
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Help with adding outlet for TV

Post by hardsoftrock » Mon Jun 24, 2019 7:00 pm

Hello. I have mounted a TV on the wall. It above a vented fireplace. Above the mantle, I have sheetrock where the TV is mounted. My house is a few years old. The wiring is in the attack and is easily accessible. My laymans knowledge is to add a junction box in the attack, splice into the existing wire, run a new wire down the wall, and add the outlet. I want to make sure I do this to code and not cut corners, so I could use some pointers.

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Aaron
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Re: Help with adding outlet for TV

Post by Aaron » Mon Jun 24, 2019 8:31 pm

The hardest bit will be fishing a line behind the drywall. If your fireplace is on an outside wall, it's going to be insulated, in which case that will be extremely difficult to put a box, if not Impossible without cutting drywall apart, and then there would be the messy task of minimizing the disturbance to the insulation and/or vapor barrier.

Inside wall is 100x easier. You just need to find where the top of that wall is in your attic and drill into the top-plate of that wall. If you need to find that plate, It's helpful to do a reference probe. Put a long, thin, and very rigid rod (think of a wire coat hanger, cut it at an angle to make it sharp) into your drill, and drill up in the corner where the wall meets the ceiling. Then you should hopefully see where it pokes through in the attic. This is just a reference hole so you can measure where the top of the wall is.

Then just measure a couple inches inward from that point and you should hit the wall top plate with a normal drill bit (use 3/8" to 1/2" hole for 14/2 NM cable).

Usually just dropping string with a weight is all you need to do.

hardsoftrock
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Re: Help with adding outlet for TV

Post by hardsoftrock » Mon Jun 24, 2019 10:10 pm

Aaron wrote:
Mon Jun 24, 2019 8:31 pm
The hardest bit will be fishing a line behind the drywall. If your fireplace is on an outside wall, it's going to be insulated, in which case that will be extremely difficult to put a box, if not Impossible without cutting drywall apart, and then there would be the messy task of minimizing the disturbance to the insulation and/or vapor barrier...
Thanks for the reply Aaron. Unfortunately, I have already added a passthrough plate (for ethernet and speaker wire), upon which time I discovered the wall is insulated. I had assumed it wasn't; The wall is at a 45 going from side wall to side wall (the fire place is in the corner). I don't like the idea of tearing out a bunch of sheetrock to do it. So am I up the creek on this one?

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Aaron
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Re: Help with adding outlet for TV

Post by Aaron » Tue Jun 25, 2019 12:11 am

Yeah it's just not an easy thing to do, with the insulation in the way, sorry to say. What's behind the insulation on that 45 degree wall? Is the exterior of the house beveled to that angle, or do you have dead space there?

hardsoftrock
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Re: Help with adding outlet for TV

Post by hardsoftrock » Tue Jun 25, 2019 6:53 pm

Aaron wrote:
Tue Jun 25, 2019 12:11 am
Yeah it's just not an easy thing to do, with the insulation in the way, sorry to say. What's behind the insulation on that 45 degree wall? Is the exterior of the house beveled to that angle, or do you have dead space there?
I am guessing there is a bunch of dead space and a chimney for the fire place.

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emtnut
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Re: Help with adding outlet for TV

Post by emtnut » Tue Jun 25, 2019 7:06 pm

You can install a receptacle, but as Aaron said, you need to take out a section of drywall to be able to maintain the vapour barrier. That way you can install a VB around the electrical box and tape it up.
Adds a bit to the job, but a bit of drywall and paint is not really a biggie. If you hired a pro, that's what he would do.

Depending on the age of the home, if it doesn't already have a proper vapour barrier then I wouldn't worry about it. If it's newer construction, then you don't really want to compromise the vapour barrier.
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hardsoftrock
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Re: Help with adding outlet for TV

Post by hardsoftrock » Wed Jun 26, 2019 5:45 pm

emtnut wrote:
Tue Jun 25, 2019 7:06 pm
You can install a receptacle, but as Aaron said, you need to take out a section of drywall to be able to maintain the vapour barrier. That way you can install a VB around the electrical box and tape it up.
Adds a bit to the job, but a bit of drywall and paint is not really a biggie. If you hired a pro, that's what he would do.

Depending on the age of the home, if it doesn't already have a proper vapour barrier then I wouldn't worry about it. If it's newer construction, then you don't really want to compromise the vapour barrier.
I cut a hole in the drywall, to see if there was a vapor barrier. There is not one. So, based on that, can I just run it in between the sheetrock and insulation?

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emtnut
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Re: Help with adding outlet for TV

Post by emtnut » Thu Jun 27, 2019 8:44 am

hardsoftrock wrote:
Wed Jun 26, 2019 5:45 pm

I cut a hole in the drywall, to see if there was a vapor barrier. There is not one. So, based on that, can I just run it in between the sheetrock and insulation?
I'd think that since there is just insulation, it is just for the chimney in behind.

So yes, you can run between the rock and insulation.
I'd use a metal fishtape, feeding from up top at the top plate, and try to fish to the recept location.
~~ Ford Ford Ford Ford Ford Ford :mrgreen: ~~

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