I am installing an outlet on the outside of my brick house and I have already run the romex to the outside by drilling a 1/2" hole through the brick. I am trying to figure out how would I attach the romex to the box. If I used a regular NM clamp, I would need to make the hole in the brick a lot bigger, like an inch or so diameter, so the box would sit flush against the brick, and so the clamp would fit inside the 1 inch hole. Is there another way to do this? Do I even need to secure the romex to the box? Or can I secure it from inside the house before it enters the hole to go outside and just caulk it or use GreatStuff to seal it?
What type of box are you using, it should be a waterproof box. These normally come with a threaded hole, which requires a male threaded clamp or conduit connector. 1/2" hole will allow nothing attached to the box to be used, use a cold chisel to enlarge the hole to fit whatever clamp you are using.
I do what you say in the last paragraph. Run the romex straight into the ho le in the back of the box, and staple it as close to the hole as you can in side the house, so nothing can catch the romex and pull it back. Works for me.
An alternative would be to enlarge the hole behind the box to fit an extern al cable clamp, and then the romex would need enough slack so that you coul d install the clamp, tighten it, then put the box on the wall. I don't thin k this is the done thing but hey, maybe an inspector would want to see that .
Or, run the romex on the wall surface into one of the side or bottom holes on the box. But that would require outdoor-rated cable or a suitable condui t and it doesn't look as nice; but it's all you can do if you want the outl et where you have no access straight from inside.
As I'm sure you know, this should be an outdoor box with a while-in-use cov er. These are ubiquitous at the big box stores. All the ones I've seen have a hole centered in the back and they come with plugs to close up the unuse d holes in the sides.
I'd caulk or seal the top and sides of the box to keep weather out of the b ox and the wall. As for sealing around the hole itself, I've always been wo rried about what effect the caulk would have on the romex sheath. I've seen firestop rated for contact with romex but I've never seen caulking or seal ant say it's ok. If the box is closed up right, mounted tight to the wall a nd caulked top and sides, I would not personally worry about the hole. Poss ibly that's not the best approach.
There is also the additonal matter of how you connect the clamp, tighten the screws on it, when it's going to be inside the hole. If you're installing it in the normal direction, ie starting from the other end and working out, that usually isn't trivial.
I think you are correct that it is supposed to have a clamp. But I've seen work done by electricians where no clamp is used. I just did one myself for an AC disconnect and it passed inspection. I had it stapled inside, close to where it exited the rim joist. That's how the existing one was done and how I've seen it done in new construction here. If it's good enough for them.....
Exactly. I'm surprised noone mentioned that awkward fact in the wiring codes. It has to be in conduit of some sort, usually in that "spiral wrapped metal" stuf (?BX?).
It's not really exposed if it comes out of a hole in the brick and into the back of box. That's what they routinely do with AC disconnects and such here passing through wood.
One idea I had was put the clamp inside the box. Obviously frst I would run the romex through the box, attach the romex to the clamp, tighten the 2 screws on the clamp, then thread the clamp onto the box until it is tight. Then finally attach the box to the wall. Is this ok?
Probably, if it will work. The threading is tapered pipe threads, it "may" be difficult to get the clamp threaded from the inside, you will have to try it first. Some boxes have a "stop" at the bottom of the threads, check to see if it is in the way for working from the inside. Use the shallowest clamps you can find so they don't interfere with the receptacle or GFI that is to go into the box.
*Use a Romex button type connector from Arlington Industries. Trim about
1/8" - 3/16" off with diagonal pliers and it will fit into the threaded opening. Stuff the hole with duct seal before mounting the box. Caulk three sides of the box and the cover.
I've been doing exactly that, since I first discovered Arlington buttons. I always feel like I'm cheating a bit, but at the end of the day, it's such a better job, and no sharp edges of the box or the Romex connector cutting into the cable.
You wouldn't have enough room inside a standard depth FS box. You'd need a deep one, then combine that with the required "in use" cover, and your outlet would be sticking six inches off the brick.
*CONFESSIONS OF AN ELECTRICIAN: I got the idea of cutting the button from you Roy. You mentioned it in an older post. Before I would just jam them into a threaded hole. Now after nipping a little off they fit perfectly. Thanks for the tip.
No idea if it's code compliant or not but I've sometimes put the clamp on inside-out, with the clamp screw inside the box. Tigten it on to the wire first, then set the clamp in the knock-out hole.
You know John, my understanding of Arlington Industries, is that they were created by electricians to solve these kinds of problems that we routinely have to deal with. That said, they need to come up with a threaded version of the button.
The romex clamp is to keep the wire from rubbing the shrap edge of the knock out hole. Since the wall hole lines up with the box hole, it's not gonna rub. No clamp needed, in my estimation.
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One idea I had was put the clamp inside the box. Obviously frst I would run the romex through the box, attach the romex to the clamp, tighten the 2 screws on the clamp, then thread the clamp onto the box until it is tight. Then finally attach the box to the wall. Is this ok?
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