Electrical question

[stl]

I am finishing up my bathroom and installing a new medicine cabinet and vanity light. With the size of the new cabinet I will have to raise the light up about 8 inches. Currently there is no junction box just Romex coming through the wall. It looks like the previous owner put 1/2 inch drywall over plaster. It looks like I am dealing with 1 inch or more of material. can I cut out and install a remodel box where I need it? I never used one before so I dont know will work in this application. or maybe I should just drill a hole a little higher and try to fish the Romex through . Any thoughts?

 

[Bigprairie1]

Re: Electrical question

Stl, By code you need a junction box...period. Fishing the cable through a new hole won't cut it and if you have a short and a fire your insurance will take a pass on it.
Anywhooo, putting a remodel/reno box in there won't be too much of a problem. Use a hole saw to go through both the drywall and the plaster.
Is the new fixture a single central fixture? If so you are going to have to centre the box on the vanity. OR is it a wide fixture wherein you could have the box biased to the left or right and not have its offset show.
You're biggest challenge will probably be whether the wire is long enough or not. (there are some ways to work through this).
Any pics?
BP

 

[stl]

Re: Electrical question

I was a little worried that the box might not work on walls that thick. I don't want to find that out after I cut a big hole in the wall. Should I use a round box? I may or may not have enough wire. It will be close. Any suggestions if the wire is too short? Thanks

 

[joed]

Re: Electrical question

Depending on the fixture a hole in the wall might be OK. Some fixtures are considered junction boxes. If the fixture has a place where you can install a cable clamp and is completely enclosed it might be OK to not have a junction box. Fluorescent fixtures commonly fall into this category.

 

[v1_0]

Re: Electrical question

I am finishing up my bathroom and installing a new medicine cabinet and vanity light. With the size of the new cabinet I will have to raise the light up about 8 inches. Currently there is no junction box just Romex coming through the wall. It looks like the previous owner put 1/2 inch drywall over plaster. It looks like I am dealing with 1 inch or more of material. can I cut out and install a remodel box where I need it? I never used one before so I dont know will work in this application. or maybe I should just drill a hole a little higher and try to fish the Romex through . Any thoughts?

Important: before you cut/drill make sure that there are no wires where you are going to cut... There are detectors for this sort of thing, I know of one type of studfinder that also detects live wires.

I'm not going to say if this is code or not, but:

If you have enough romex - ie, the wire was just fished through the wall and wasn't hooked up - then you could put a box in higher. (cut the hole, fish the wire through - slide the box on up the wire and into the hole...). There are two types of boxes that you can buy at HD/Lowes/etc: new construction and existing construction. If you are right next to a 2x4 with your hole you can use the new construction one and put a couple of (short) screws through the box at an angle into the 2x4. IF you know for a fact that there are no wires run on the other side of the 2x4. If the hole isn't going to be next to anything then you want the existing construction box: there's usually a couple of screws with tabs on the box, and it has a bigger "lip". The box slides into the wall up to the lip. When you tighten the screws, the tabs flip out and 'grab' onto the backside of the wall. You tighten it until the box won't move. If you haven't slid the box up the wire, you will now notice the lack of wire in the box and start cussin. If you back out the screws a bit, the flaps will flip back along side the box and you can pull it out...


If you don't have enough wire you will need to create a junction box somewhere ('upstream' on the existing wire) and run a new wire from the junction box to where you want your light. A junction box will need to be covered, but not "covered over" by your drywall. You could put an outlet in the box - would draw less attention then a blank wall plate.

At any rate, since you are working in the bathroom there are codes about how close things can be to where there is water. You want to find out what they are for your locale, and follow them. They will also let you know what type of breakers you need on the circuit (probably not 'regular' ones, you will need GFI or maybe that newer type).

 

[v1_0]

Re: Electrical question

I was a little worried that the box might not work on walls that thick. I don't want to find that out after I cut a big hole in the wall. Should I use a round box? I may or may not have enough wire. It will be close. Any suggestions if the wire is too short? Thanks

Check the (existing construction) box out before you buy it. The 'flap' on the side should not be able to spin all the way 'round. (Then it won't screw tight...) Figuring out when it starts 'not spinning' would give you the maximum thickness that it would work in.

There may be other types of existing construction boxes that do things differently.

And, the boxes themselves come in different 'depths' too.