Fishing electrical in exterior walls

[John in Calgary]

I need to fish the electrical wire in for a plug to be located above the fireplace in our den for our TV. Since this is an exterior wall, behind the gyproc is a vapour barrier and insulation.

My plan was to cut a hole in the gyproc without penetrating the vapour barrier, then use a renovation box (the kind with the ears that snug up against the gyproc to hold it in place) pushed into the hole against the vapour barrier - in other words, the box would push against the vapour barrier and insulation, not go through the vapour barrier.

To fish the wire to the box, I plan to cut another access hole through the gyproc inside the framing for my new fireplace. The wiring would be fished between the two holes, sliding between the vapour barrier and the gyproc. Once inside the framing for the fireplace, I will drill a hole through the floor within the fireplace framing so the line can be dropped down into the ceiling of the garage and on to a power source.

I'm trying to install this in such a way that I don't have extra penetrations through the vapour barrier (since, in my mind, they can be more difficult to repair) and so I don't have to try to drill up into the lower plate of the wall from the garage ceiling (since its 15' in the air and gyproc'd in to keep the floor in the room above warm).

Anyone see any code issues (or other logistical issues) with what I'm trying to do?

Thanks

John

[billh]

Have you done this before? With the gyproc tight up against the vapour barrier I don't see how you are going to cut the hole and not damage the vapour barrier let alone fish a wire between the barrier and the gyproc. Hopefully, you don't have any blocking in the way.

billh

[Mike in London]

Hi John

I don't see a problem with what you're describing, but I agree with Bill, you're going have a very difficult time not penitrating the vapour barrier.

I do have couple questions, what were you planning on tieing into for a power source? Also what about a power source for the blower on your fireplace, I assume it's gas. If it's electric you'll have to go directly to your panel for new circuit.

Mike

[Lee Brubaker in Edmonton]

Vapor barrier is easily punctured especially if you don't wanna. Suggest that once you have the hole cut, duct tape the vapor barrier to protect it.

Lee

[John in Calgary]

Thanks everyone, Mike's thumbs up was what I was looking for on the electrical side.

I agree that vapour barrier is pretty easy to puncture, but I'm sure there is enough slack to fish the wire in once I get the holes cut. The studs are on 2' centres and I recently cut a 10"x10" hole in the wall for the chimney and, without cutting the vapour barrier, there seemed to be 1-1 1/2" of slack when I pushed on the barrier. That said, I've probably cursed myself this time round and will puncture it. I'm also sure there is no blocking behind this part of the wall (we had the house built 5 years ago).

I like the duct tape idea, I think I'll put some behind the box before I try to insert it to make sure it doesn't puncture.

As for Mike's question regarding power source, for now I was going to drop the line through the floor into the ceiling of the garage. Then, when I get around to wiring the garage, I will plan for it at the same time.

No blower on the fireplace, I've purchased one of these:

http://www.valorflame.com/products/index.php?page=82

It will be along one wall of our 12x12 den. Between the radiant heat and the great turn down (fuel turndown is controlled by the remote control's thermostat, instead of on/off like a more traditional gas fireplace), I'm excited about trying this thing out.

I'll post photos once I get it installed/trimmed.

John

[ERic In Nova Scotia]

Hey John, I may be too late with this but I'll say it anyway. The trick to not cutting the poly is to take your time with an exacto knife. Start with the blade only extending out an 1/8" untill the blade has scored the entire cut equaly. Then extend the blade another 1/8" and so on and so on. Keep a tape or ruler close so you know when the blade is out 1/2". at this point you should be able to feel the difference between the drywall and the the paper on the other side. Carefully cut the paper and your in.

I use this trick for when I need into a wall all the time (well ok not that often but when I do...) if you do need to cut the poly for some reason, if the drywall hole is bigger than the poly hole then you have undamaged poly to tape a patch to. If the 2 holes are the same size, fixing the poly is near imposible. More info than you asked for, but that is what I'm here for....